Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically ~~and posted on its corporate Web site, if any,~~ every Interactive Data File required to be submitted ~~and posted~~ pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit ~~and post~~ such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☒☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The number of outstanding shares of the registrant’s common stock on ~~October 31, 2017~~May 1, 2020 was ~~35,741,036~~46,680,808 shares.

	September 30, 2017			December 31, 2016			March 31, 2020			December 31, 2019
Assets
Current assets
Cash and cash equivalents	$	227,184		$	135,797		$	131,204		$	101,436
Short-term investments		19,993			4,072			218,809			314,691
Receivable from collaboration partner		—			45,000
Prepaid expenses and other current assets		1,545			1,394			7,486			7,709
Total current assets		248,722			186,263			357,499			423,836
Property and equipment, net		2,633			2,758			19,801			15,743
Operating lease right-of-use assets								51,981			417
Long-term investments		36,003			12,002			10,077			14,153
Other long-term assets		432			283
Restricted cash and other								1,968			1,945
Total assets	$	287,790		$	201,306		$	441,326		$	456,094
Liabilities and stockholders’ equity
Current liabilities
Accounts payable	$	2,030		$	1,798			5,573		$	6,237
Accrued liabilities		10,634			8,690			32,236			41,292
Deferred revenue - current		22,500			22,500
Operating lease liabilities - current								7,851			383
Total current liabilities		35,164			32,988			45,660			47,912
Operating lease liability								44,658			—
Other long-term liabilities		246			436			1,908			1,908
Deferred revenue - noncurrent		5,625			22,500
Total liabilities		41,035			55,924			92,226			49,820
Commitments and contingencies (Note 6)
Commitments and contingencies (Note 7)
Stockholders’ equity
Preferred stock, $0.0001 par value; 5,000,000 shares authorized; none issued and outstanding		—			—
Common stock, $0.0001 par value, 150,000,000 and 150,000,000 shares authorized at September 30, 2017 and December 31, 2016, respectively; 35,733,002 and 31,428,998 shares issued and outstanding at September 30, 2017 and December 31, 2016, respectively		4			3
Preferred stock, $0.0001 par value; 5,000,000 shares authorized; NaN issued and outstanding								—			—
Common stock, $0.0001 par value, 150,000,000 shares authorized at March 31, 2020 and December 31, 2019; 46,612,186 and 46,379,073 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively								5			5
Additional paid-in capital		363,205			223,208			897,058			884,486
Accumulated other comprehensive (loss) income		(52	)		8
Accumulated other comprehensive income								671			549
Accumulated deficit		(116,402	)		(77,837	)		(548,634	)		(478,766	)
Total stockholders’ equity		246,755			145,382			349,100			406,274
Total liabilities and stockholders’ equity	$	287,790		$	201,306		$	441,326		$	456,094

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

	Three Months Ended September 30,						Nine Months Ended September 30,						Three Months Ended March 31,
	2017			2016			2017			2016			2020			2019
Collaboration and license revenue	$	5,625		$	3,550		$	16,875		$	10,649
Operating expenses:
Research and development		14,361			8,783			39,967			26,192		$	51,878		$	26,190
General and administrative		5,884			4,031			16,442			11,947
Selling, general and administrative														19,902			13,551
Total operating expenses		20,245			12,814			56,409			38,139			71,780			39,741
Loss from operations		(14,620	)		(9,264	)		(39,534	)		(27,490	)		(71,780	)		(39,741	)
Interest and other income, net		447			33			977			79			1,912			2,271
Net loss		(14,173	)		(9,231	)		(38,557	)		(27,411	)		(69,868	)		(37,470	)
Other comprehensive loss		2			—			60			—
Other comprehensive income														122			363
Comprehensive loss		(14,171	)		(9,231	)		(38,497	)		(27,411	)	$	(69,746	)	$	(37,107	)
Net loss attributable to common stockholders	$	(14,173	)	$	(9,231	)	$	(38,557	)	$	(27,411	)
Net loss per share attributable to common stockholders, basic and diluted	$	(0.42	)	$	(0.35	)	$	(1.21	)	$	(1.04	)
Weighted average number of shares used to compute net loss per share attributable to common stockholders, basic and diluted		33,525,567			26,470,298			31,951,631			26,331,852
Net loss per share, basic and diluted													$	(1.50	)	$	(0.93	)
Weighted average number of shares used to compute net loss per share, basic and diluted														46,566,995			40,506,313

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

For the three months ended March 31, 2020
					Additional		Accumulated other					Total
	Common Stock				Paid-In		comprehensive		Accumulated			Stockholders’
	Shares		Amount		Capital		income		Deficit			Equity
BALANCE—December 31, 2019		46,379,073	$	5	$	884,486	$	549	$	(478,766	)	$	406,274
Issuance of common stock upon the exercise of options and release of stock awards		233,113		—		1,820		—		—			1,820
Stock-based compensation		—		—		10,752		—		—			10,752
Unrealized gains		—		—		—		122		—			122
Net loss		—		—		—		—		(69,868	)		(69,868	)
BALANCE—March 31, 2020		46,612,186	$	5	$	897,058	$	671	$	(548,634	)	$	349,100

For the three months ended March 31, 2019
					Additional		Accumulated other						Total
	Common Stock				Paid-In		comprehensive			Accumulated			Stockholders’
	Shares		Amount		Capital		income/ (loss)			Deficit			Equity
BALANCE—December 31, 2018		40,288,949	$	4	$	573,183	$	(67	)	$	(202,553	)	$	370,567
Issuance of common stock in connection with the 2019 follow-on offering, net of issuance costs of $17,638		5,663,750		1		271,212		—			—			271,213
Issuance of common stock upon the exercise of options and release of stock awards		49,076		—		280		—			—			280
Vesting of early exercised stock options		—		—		8		—			—			8
Stock-based compensation		—		—		6,981		—			—			6,981
Unrealized gains		—		—		—		363			—			363
Net loss		—		—		—		—			(37,470	)		(37,470	)
BALANCE—March 31, 2019		46,001,775	$	5	$	851,664	$	296		$	(240,023	)	$	611,942

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

	Nine Months Ended September 30,						Three Months Ended March 31,
	2017			2016			2020			2019
Cash flows from operating activities:
Cash flow from operating activities:
Net loss	$	(38,557	)	$	(27,411	)	$	(69,868	)	$	(37,470	)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense		4,347			1,781			10,752			6,981
Depreciation		977			815			779			461
Accretion of discounts and amortization of premiums on investments		62			—
Amortization of discount on investments								(418	)		(292	)
Loss on disposal of equipment								49			—
Change in operating assets and liabilities:
Receivable from collaboration partner		45,000			—
Prepaid expenses and other current assets		(151	)		520			226			448
Operating lease right-of-use assets								1,066			635
Other long-term assets		(149	)		—			—			(13	)
Accounts payable		228			(372	)		(467	)		1,950
Accrued liabilities		2,029			1,027			(1,512	)		(180	)
Prepayment from collaboration partner								—			(9,874	)
Operating lease liabilities								(504	)		—
Other long-term liabilities		(118	)		(75	)		—			(692	)
Deferred revenue		(16,875	)		(10,649	)
Net cash used in operating activities		(3,207	)		(34,364	)		(59,897	)		(38,046	)
Cash flows from investing activities:
Cash flow from investing activities:
Purchases of investments		(44,044	)		—			—			(32,697	)
Sale of investments		4,000			—
Sales of investments								4,000			4,000
Maturities of investments								96,475			16,000
Purchases of property and equipment		(917	)		(854	)		(12,627	)		(813	)
Net cash used in investing activities		(40,961	)		(854	)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of offering costs		133,925			—
Net cash provided by (used in) investing activities								87,848			(13,510	)
Cash flow from financing activities:
Proceeds from issuance of common stock in follow-on offerings, net of issuance and financing costs								—			271,485
Proceeds from exercise of stock options and employee stock purchase plan		1,668			226			1,817			280
Payments of prior period offering costs		(38	)		(153	)
Net cash provided by financing activities		135,555			73			1,817			271,765
Net increase (decrease) in cash and cash equivalents		91,387			(35,145	)
Cash and cash equivalents, beginning of period		135,797			112,265
Cash and cash equivalents, end of period	$	227,184		$	77,120
Supplemental disclosures of noncash investing and financing activities
Unpaid offering costs included in period-end accounts payable and accrued liabilities	$	63		$	461
Net increase in cash, cash equivalents and restricted cash								29,768			220,209
Cash, cash equivalents and restricted cash, beginning of period								103,630			248,265
Cash, cash equivalents and restricted cash, end of period							$	133,398		$	468,474
Non-cash investing and financing activities:
Unpaid portion of property and equipment purchases included in period-end accounts payable and accrued liabilities							$	2,015		$	570
Vesting of early exercised options and restricted stock	$	156		$	226		$	—		$	8
Unpaid portion of property and equipment purchases included in period-end accounts payable and accrued liabilities	$	38		$	7
Unpaid financing-related costs							$	—		$	262

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

MyoKardia, Inc. (the ~~“Company”)~~Company) is a ~~clinical stage~~clinical-stage biopharmaceutical company pioneering a precision medicine approach to discover, develop and commercialize targeted therapies for the treatment of serious and neglected rare cardiovascular diseases. ~~Our~~The Company’s initial focus is on the treatment of ~~heritable~~ cardiomyopathies, a group of ~~rare, genetically-driven forms~~diseases of the heart muscle. MyoKardia’s pipeline includes: mavacamten and MYK-224, which are being studied for the treatment of hypertrophic cardiomyopathy; LUS-1, being studied for the treatment of diseases of diastolic dysfunction; and danicamtiv (formerly MYK-491) and ACT-1, being studied for the treatment of diseases of systolic dysfunction.

MyoKardia’s most advanced programs are: mavacamten, which is in four clinical trials including a Phase 3 study in patients with hypertrophic cardiomyopathy (HCM); danicamtiv, which recently completed a Phase 2a multiple-ascending dose study in patients with stable systolic heart failure ~~that result from biomechanical defects~~and is being advanced to a Phase 2 study in ~~cardiac muscle contraction. We have used our precision medicine platform to generate~~patients with genetic dilated cardiomyopathy; and MYK-224, which is in a ~~robust pipeline of therapeutic programs for the chronic treatment of the two most common forms of heritable cardiomyopathy—hypertrophic cardiomyopathy (“HCM”),~~Phase 1 randomized, placebo-controlled study in healthy volunteers.

The Company was incorporated on June 8, 2012 in Delaware and ~~dilated cardiomyopathy (“DCM”).~~its corporate headquarters and operations are in Brisbane, California.

The Company has ~~completed enrollment in a Phase 2 clinical trial~~incurred significant operating losses since inception and has an accumulated deficit of ~~mavacamten (formerly known~~$548.6 million as ~~MYK-461), our product candidate for the treatment~~ of HCM, and is currently enrolling subjects in a Phase 1 clinical trial of MYK-491, our product candidate for the treatment of DCM. Using our precision medicine development strategy, we believe we have efficiently generated clinical proof of mechanism for mavacamten in both healthy volunteers and in HCM patients, and we intend to pursue a similar path for MYK-491. In 2016, mavacamten was granted Orphan Drug Designation by the U.S. Food and Drug Administration (“FDA”), for the treatment of symptomatic, obstructive hypertrophic cardiomyopathy (“oHCM”), a subset of HCM.

~~Through September 30, 2017, the~~March 31, 2020. The Company has ~~financed~~relied on its ability to fund its operations through ~~an initial~~private and public ~~offering (“IPO”), two follow-on public offerings, private placements of redeemable convertible preferred stock~~equity financings and ~~funds received in connection with~~to a lesser extent, through a license and collaboration ~~agreement~~arrangement with a collaboration partner, Sanofi S.A. (Sanofi) via its subsidiary, Aventis Inc.~~, a wholly-owned subsidiary~~ The collaboration agreement ended on December 31, 2018 and the Company had no revenues relating to its Sanofi collaboration after December 31, 2018, nor has it received reimbursements of ~~Sanofi S.A., entered into in August 2014 (the “Collaboration Agreement”) (See Note 4).~~research and development expenses after June 30, 2019. The Company has not yet received ~~net proceeds~~regulatory approval to commercialize or sell any product and does not have customers. Management expects operating losses and negative operating cash flows to continue for the foreseeable future. As the Company continues to incur losses, a transition to profitability is dependent upon the successful development, approval, and commercialization of ~~$93.9 million from~~ the ~~sale~~Company’s products and product candidates and the achievement of ~~shares~~a level of revenues adequate to support its cost structure. The Company’s ultimate success depends on the outcome of its ~~Series A, A-1~~research and ~~B redeemable convertible preferred stock. On November 3, 2015,~~development activities and anticipates the need to raise additional capital to fully implement its business plan. The Company intends to raise such capital through the issuance of additional equity, debt and/or strategic alliances with partner companies. There is no assurance that such financing will be available or that such strategic alliances will be executed on terms acceptable to the Company, ~~completed its IPO~~or at all.

As of 6,253,125 shares of common stock at an offering price of $10.00 per share, resulting in net proceeds of approximately $55.6 million, after deducting underwriting discounts, commissions and offering costs. On October 3, 2016,March 31, 2020, the Company ~~completed a follow-on public offering~~had $360.1 million of ~~4,370,000 shares~~cash, cash equivalents and short and long-term investments, which management believes will be sufficient to meet the Company’s anticipated operating and capital expenditure requirements for the twelve months following the date of ~~common stock at an offering price~~issuance of ~~$15.00 per share, resulting in net proceeds of approximately $61.1 million, after deducting underwriting discounts, commissions~~these financial statements. Management’s belief with respect to its ability to fund operations is based on estimates that are subject to risks and ~~estimated offering costs. On August 14, 2017,~~uncertainties. If actual results are different from management’s estimates, the Company ~~completed another follow-on public offering of 4,025,000 shares of common stock at an offering price of $35.50 per share, resulting~~may need to seek additional funding. In addition, the Company is closely monitoring ongoing developments in ~~net proceeds of approximately $133.8 million, after deducting underwriting discounts, commissions and estimated offering costs. In~~ connection with the ~~Collaboration Agreement, the~~COVID-19 pandemic, which may negatively impact its financial and operating results.

The Company has received $105.0 million from Sanofi S.A., consisting of a $35.0 million upfront payment, a $25.0 million milestone payment for the submission of an investigational new drug application (“IND”) for MYK-491 with the FDA in November 2016, and a $45.0 million continuation payment from Sanofi in January 2017. As of September 30, 2017, the Company had an accumulated deficit of $116.4 millionwill continue to assess its operating expenses and cash and cash equivalents and, if circumstances warrant, the Company will make appropriate adjustments to its operating plan.

2. Basis of ~~$227.2 million, short-term investments~~Presentation and Summary of ~~$20.0 million and long-term investments~~Significant Accounting Policies

The accompanying unaudited Condensed Consolidated Financial Statements, in the opinion of management, include all adjustments which the Company considers necessary for the fair statement of the Condensed Consolidated Results of Operations and Comprehensive Loss and Cash Flows for the interim periods covered and the Condensed Consolidated Financial Position of the Company at the date of the balance sheets. Thecondensed consolidated financial statements ~~of the Company as at December 31, 2016 included~~are unaudited, include the Company’s accounts and those of its wholly-owned subsidiaries MyoKardia Australia Pty Ltd and MyoKardia Netherlands B.V., and have been prepared in conformity with accounting principles generally accepted in the United States of America (“USU.S. GAAP”).

The condensed consolidated balance sheet at December 31, 2019, has been derived from the audited consolidated financial statements as of that date but does not include all of the information and footnotes required by U.S. GAAP for complete financial statements. The results of operations for the interim ~~results presented herein~~periods are not necessarily indicative of the results of operations ~~that may~~to be expected for the full fiscal year ~~ending December 31, 2017,~~ or any ~~other future period.~~

~~The accompanying unaudited Condensed Consolidated Financial Statements~~interim period and ~~related financial information~~ should be read in conjunction with the ~~Company’s~~ audited ~~consolidated~~ financial statements ~~and the related notes thereto~~ for the year ended

December 31, ~~2016~~2019 and the notes thereto, which are included in the Company’s Annual Report on Form 10-K as of and for the year ended December 31, ~~2016~~ ~~filed with the U.S. Securities and Exchange Commission (the “SEC”) on March 13, 2017 (the “Annual Report”).~~

~~Significant~~2019. The significant accounting policies used in preparation of these condensed consolidated financial statements for the periods shown are ~~described~~consistent with those discussed in ~~Note 2~~notes to the consolidated financial statements in the Company’s 2019 Annual Report on Form 10-K and are updated below as necessary.

The Company currently operates in 1 business segment, which is the identification, development and commercialization of therapies for the ~~year ended December 31, 2016 included~~treatment of serious and neglected rare cardiovascular diseases and has a single reporting unit and operating segment. These interim statements, in the ~~Annual Report. There have been no changes to~~opinion of management, reflect all normal recurring adjustments necessary for the fair statement of the Company’s ~~significant accounting policies during~~financial position and results of operations for the ~~nine months~~interim periods ended ~~September 30, 2017, except~~March 31, 2020 and 2019, respectively.

Reconciliation of Cash, Cash Equivalents, and Restricted Cash as ~~described below.~~Reported in Consolidated Statements of Cash Flows

~~Beginning~~Cash as reported in ~~fiscal year 2017,~~ the ~~Company adopted~~ ~~Accounting Standard Update (“ASU”)~~ ~~No. 2016-09, Improvements to employee share-based payment accounting,~~ which simplifies the accounting for employee share-based transactions. The amendments change, among other things, the recognition of excess tax benefits and deficiencies, the classification of those excess tax benefits on the statementconsolidated statements of cash flows ~~an accounting policy election for forfeitures,~~includes the ~~amount an employer can withhold~~aggregate amounts of cash, cash equivalents and restricted cash as presented on the consolidated balance sheets. Restricted cash at March 31, 2020 and December 31, 2019 represents cash balances held as security in connection with the Company’s facility lease agreements. The following table provides a reconciliation of cash, cash equivalents and restricted cash within the consolidated balance sheets to ~~cover income taxes~~the total shown in the consolidated statements of cash flows (in thousands):

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and ~~still qualify for equity classification,~~assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities and the ~~classification~~reported amounts of revenues and expenses in the consolidated financial statements and the accompanying notes. On an ongoing basis, management evaluates its estimates, including those ~~taxes paid~~related to clinical trials accrued liabilities, income tax valuation allowance and stock-based compensation. Management bases its estimates on historical experience and on various other market-specific and relevant assumptions that management believes to be reasonable under the ~~statement~~circumstances. Actual results could differ from those estimates.

In November 2018, the Financial Accounting Standards Board (FASB) issued ASU 2018-18 (Topic 808), Clarifying the Interaction Between Topic 808 and Topic 606, which provides guidance on how to assess whether certain transactions between collaborative arrangement participants should be accounted for within the revenue recognition standard. The ASU also provides more comparability in the presentation of ~~cash flows.~~revenue for certain transactions between collaborative arrangement participants. It accomplishes this by allowing organizations to only present units of account in collaborative arrangements that are within the scope of the revenue recognition standard together with revenue accounted for under the revenue recognition standard. The parts of the collaborative arrangement that are not in the scope of the revenue recognition standard should be presented separately from revenue accounted for under the revenue recognition standard. The Company adopted ~~ASU 2016-09~~this amendment in the first quarter of 2017. As a result of adopting this standard, we have made an accounting policy election to account for forfeitures as they occur. This change has been applied on a modified retrospective basis, resulting in an immaterial cumulative effect adjustment to2020 and the ~~opening accumulated deficit on January 1, 2017. Upon~~ adoption ~~the previously unrecognized excess tax benefits were recorded as a deferred tax asset, which was fully offset by a valuation allowance resulting in no impact to the accumulated deficit.~~

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”), or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the impact of recently issued standards that are not yet effective willdid not have a material impact onto the Company’s ~~consolidated~~ financial statements upon adoption. Under the Jumpstart Our Business Startups Act of 2012, as amended (the “JOBS Act”), the Company meets the definition of an emerging growth company, and has irrevocably elected to opt out of the extended transition period for complying with new or revised accounting standards pursuant to Section 107(b) of the JOBS Act.statements.

In ~~May 2017,~~August 2018, the FASB issued ASU ~~2017-09—Compensation—Stock Compensation~~2018-13 (Topic ~~718): Scope of Modification Accounting.~~ ~~The amendments in this ASU provide guidance about~~820), Fair Value Measurement, which ~~changes to~~modifies the terms or conditions of a share-based payment award require an entity to apply modification accounting in Topic 718 to address diversity in practice. An entity should account for the effects of a modification unless all the three specified conditions are met. The current disclosure requirements in Topic ~~718 apply regardless~~820 by removing requirements for disclosing (i) amounts of ~~whether an entity is required~~and reasons for transfers between the Level 1 and Level 2 hierarchies, (ii) the policy for timing of transfers between levels and (iii) the valuation processes for Level 3 fair value measurements. The ASU 2018-13 amendment also adds requirements for disclosure of changes in unrealized gains and losses for the period relating to ~~apply modification accounting under~~Level 3 fair value measurements and other factors considered in the amendments in this ASU. The amendments in this ASU are effective for all entities for annual periods, and interim periods within those annual periods, beginning after December 15, 2017, with early adoption permitted. The amendments in this ASU should be applied prospectively to an award modified on or after the adoption date. valuation of Level 3 investments. The Company ~~has not determined the potential effects of~~adopted this ~~ASU on its consolidated financial statements.~~

~~In November 2016, the FASB issued~~ ~~ASU~~ ~~No. 2016-18 (Topic 230), Restricted Cash, Statement of Cash Flows. This ASU 2016-18 requires that a state~~ment of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for public business entities for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years, with early adoption permitted. The amendments in this ASU should be applied using a retrospective transition method to each period presented. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements.

In ~~February~~ ~~2016, the FASB issued~~ ~~ASU No. 2016-02 (Topic 842), Leases.~~ ~~This ASU~~ requires an entity to recognize assets and liabilities arising from a lease for both financing and operating leases. The ASU will also require new qualitative and quantitative disclosures to help investors and other financial statement users better understand the amount, timing, and uncertainty of cash flows arising from leases. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, with early adoption permitted. ~~The Company has not determined the potential effects of this ASU on its consolidated financial statements.~~

~~In May 2014, the FASB issued~~ ~~ASU No. 2014-09 (Topic 606), Revenue from Contracts with Customers, which supersedes the revenue recognition requirements in~~ ~~ASC 605, Revenue Recognition.~~ This ASU is based on the principle that revenue is recognized to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. In March, April, and May 2016, the FASB issued amended guidance including clarifying guidance on principal versus agent considerations, identification of performance obligations, collectability and noncash considerations. ASU 2014-09 and its amendments are effective for public entities for annual and interim periods beginning after December 15, 2017; therefore, the Company will adopt the new revenue standardsamendment in the first quarter of ~~2018. Since its formation,~~2020 and the ~~Company has only had transactions~~adoption did not have a material impact to the Company’s financial statements.

In June 2016, the FASB issued ASU No. 2016-13 (Topic 326), Financial Instruments –Measurement of Credit Losses on Financial Instruments, which ~~are recognized in revenue which relate~~requires measurement and recognition of expected credit losses for financial assets by requiring an allowance to ~~its Collaboration Agreement with Sanofi S.A.~~be recorded as an offset to the amortized cost of such assets. For available-for-sale debt securities, expected credit losses

should be estimated when the fair value of the debt securities is below their associated amortized costs. The Company is evaluating whether or not the identification of performance obligations and determination of their stand-alone values would remain unchanged under the new revenue standards. The Company plans to adopt the standardadopted this amendment in the first quarter of ~~fiscal year 2018 by applying~~2020 and the ~~full retrospective method. The~~adoption did not have a material impact to the Company’s ~~ability to adopt using the full retrospective method is dependent on the~~

~~completion of its analysis of information necessary to restate prior period~~ financial statements. ~~The Company is continuing to evaluate the accounting, transition and disclosure requirements of the standard and is in process of assessing the financial statement impact of adoption.~~

Until December 31, 2018 the Company had an exclusive license and collaboration agreement (Collaboration Agreement) with Aventis Inc., a wholly-owned subsidiary of Sanofi S.A. (Sanofi). On December 31, 2018, Sanofi notified the Company of its intent to terminate the collaboration, specifically, Sanofi elected not to continue with the mavacamten, MYK-224 and danicamtiv programs. As a result, cost sharing and Sanofi’s reimbursement of our research and development costs for mavacamten and MYK-224 ended in the first half of 2019. At that time Sanofi had continuing rights to royalties in the event of commercialization of the mavacamten and MYK-224 programs. In July 2019, the Company repurchased those rights from Sanofi for $80.0 million. Neither the Company nor Sanofi have any material continuing rights or obligations under the Collaboration Agreement.

~~Financial~~Fair value accounting is applied for all financial assets and liabilities, including short-term and long-term investments and non-financial assets and liabilities that are ~~recorded~~recognized or disclosed at fair ~~value.~~ value in the consolidated financial statements on a recurring basis (at least annually). The carrying amount of the Company’s financial instruments, including accounts payable and accrued liabilities and other current liabilities approximate fair value due to their short-term maturities.

Marketable securities are stated at their estimated fair values. The counterparties to the agreements relating to the Company’s investment securities consist of the U.S. Treasury, governmental agencies, various major corporations and financial institutions with high credit standing. The carrying amounts for financial instruments consisting of cash and cash equivalents, receivable from collaboration partner, accounts payable and accrued liabilities approximate fair value due to their short maturities.

The accounting guidance for fair value provides a framework for measuring fair value, clarifies the definition of fair value and expands disclosures regarding fair value measurements. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The accounting guidance establishes a three-tiered hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value as follows:

Level 1—Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.

Level 2—Inputs other than quoted market prices included in Level 1 are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life.

Level 3—Inputs reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands):

	Fair Value Measurements at September 30, 2017								Fair Value Measurements at March 31, 2020
	Total		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3
Assets
Money market funds	$	227,466	$	227,466	$	—	$	—	$	130,176	$	130,176	$	—	$	—
U.S. government agency obligations		31,963		—		31,963		—		107,657		—		107,657		—
Corporate securities		24,033		—		24,033		—		121,229		—		121,229		—
Total	$	283,462	$	227,466	$	55,996	$	—	$	359,062	$	130,176	$	228,886	$	—

	Fair Value Measurements at December 31, 2016								Fair Value Measurements at December 31, 2019
	Total		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3
Assets
Money market funds	$	136,481	$	136,481	$	—	$	—	$	100,441	$	100,441	$	—	$	—
U.S. government agency obligations		12,075		—		12,075		—		134,055		—		134,055		—
Corporate securities		3,999		—		3,999		—		194,789		—		194,789		—
Total	$	152,555	$	136,481	$	16,074	$	—	$	429,285	$	100,441	$	328,844	$	—

The following table is a summary of amortized cost, unrealized gain and loss, and fair value ~~(in thousands)~~ of the Company’s marketable securities by contractual ~~maturities:~~

	Fair Value Measurements at September 30, 2017									Fair Value Measurements at March 31, 2020
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash equivalents (due within 90 days)	$	227,466	$	—	$	—		$	227,466	$	130,153	$	23	$	—		$	130,176
Short-term investments (due within one year)		20,009		—		(16	)	$	19,993		218,129		827		(147	)		218,809
Long-term investments (due between one and two years)		36,033		3		(33	)	$	36,003		10,104		27		(54	)		10,077
Total	$	283,508	$	3	$	(49	)	$	283,462	$	358,386	$	877	$	(201	)	$	359,062

	Fair Value Measurements at December 31, 2016									Fair Value Measurements at December 31, 2019
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash equivalents (due within 90 days)	$	136,481	$	—	$	—		$	136,481	$	100,440	$	1	$	—		$	100,441
Short-term investments (due within one year)		4,072		—		—			4,072		314,181		523		(13	)		314,691
Long-term investments (due between one and two years)		11,988		14		—			12,002		14,110		47		(4	)		14,153
Total	$	152,541	$	14	$	—		$	152,555	$	428,731	$	571	$	(17	)	$	429,285

In August 2014, the Company entered into the Collaboration Agreement with Aventis Inc., a wholly-owned subsidiary of Sanofi S.A., for the research, development and potential commercialization of pharmaceutical products for the treatment, prevention and diagnosis of hypertrophic and dilated cardiomyopathy, as well as potential additional indications.

Pursuant to the Collaboration Agreement, in addition to potential future royalty payments, Sanofi agreed to provide up to $200.0 million in financial consideration to the Company consisting of the following components:

The Company determines if an arrangement is ~~also entitled to receive tiered royalties beginning in the mid-single digits to the mid-teens~~or contains a lease at inception. Operating lease right-of-use (ROU) assets and liabilities are presented separately on ~~net sales of certain hypertrophic cardiomyopathy (“HCM”)~~our consolidated balance sheets. The Company does not have any finance leases.

Operating lease ROU assets and dilated cardiomyopathy (“DCM”) finished products outside the United States and on net sales of certain DCM finished products in the United States. Sanofi is eligible to receive tiered royalties beginning in the mid-single digits to the low teensoperating lease liabilities are recognized based on the ~~Company’s net sales of certain HCM finished products in the United States. In addition, under the terms~~present value of the ~~Collaboration Agreement, Sanofi may reimburse~~future minimum lease payments over the lease term beginning at the commencement date. As the Company’s leases do not provide enough information to determine an implicit interest rate, the Company ~~for a portion of the registration program costs for mavacamten. These registration costs will be reimbursed under the Registration Program Plan approved in October 2017.~~

The Collaboration Agreement covers three main research programs, “HCM1” (or HCM-1 or mavacamten, formerly known as MYK-461), “HCM2” (or HCM-2) and “DCM1” (or DCM-1 or MYK-491). The Company is solely responsible for conducting research and development activities through early human efficacy studies, except for specified research activities to be conducted by Sanofi. The estimated completion of proof-of-concept phases are staggered, dependingdetermines its incremental borrowing rate based on the ~~program. Thereafter,~~rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term in a similar economic environment. The operating lease ROU assets also include any lease payments made and excludes lease incentives and initial direct costs incurred. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will ~~lead worldwide development and United States commercial activities~~exercise that option. Lease expense for the mavacamten and HCM-2 programs, Sanofi will lead global development and commercial activities for DCM-1 and Sanofi will lead ex-United States development and commercial activities for the mavacamten and HCM-2 programs where it has ex-United States commercialization rights. Sanofi also has the option to co-promote in the U.S. for potential expanded cardiovascular diseases outside of the genetically targeted indications for the mavacamten and HCM-2 programs, with the Company having the option to co-promote the DCM-1 program in the United States.

~~The Company accounted for the Collaboration Agreement by evaluating each of the financial components discussed above:~~

Sanofi elected to continue the Collaboration Agreement in December 2016. The Company recorded a receivable and deferred revenue as of December 31, 2016 for the $45.0 million continuation payment, upon receipt of the election to continue, which the Company is recognizing on a straight-line basis over the ~~expected term~~lease term.

In September 2018, the Company entered into a lease agreement (the “Lease”) for approximately 129,800 square feet of ~~research~~office and ~~development services through December 31, 2018 because there~~laboratory space in Brisbane, California, which is ~~no more discernable pattern~~now the Company’s corporate headquarters. The Company performed an evaluation of ~~performance for which~~ the ~~R&D services occur.~~Lease and determined it is an operating lease. The ~~payment~~lease commencement date was ~~subsequently received~~ in January ~~2017. In relation to this continuation payment,~~2020 and on the commencement date, the Company recognized ~~$5.6~~$52.6 million of ROU asset and ~~$16.9 million as revenue during the three and nine months ended September 30, 2017, respectively, and had deferred revenue~~lease liability on its consolidated balance sheet in accordance with ASC 842. The Lease grants the Company an option to extend the Lease for an additional 10-year period. This optional period was not included in the measurement of ~~$28.1~~the ROU asset or lease liability as it was not reasonably certain that the Company would exercise the option. The Lease requires the Company to share in prorated operating expenses and property taxes based upon actual amounts incurred. These expenses were classified as variable lease costs due to the Company’s election to account for each separate lease component and the non-lease components associated with that lease component as a single lease component.

The Lease provides for annual base rent of approximately $5.5 million in the first year of the lease term. The annual base rent for the second twelve months will be approximately $8.5 million, which will increase on an annual basis beginning from the 25th month to approximately $11.1 million for the tenth year of the lease.

As of March 31, 2020, the Company has capitalized $10.6 million of leasehold improvements within property and equipment and amortizes it over the lease term.

Supplemental balance sheet information related to operating leases was as follows (in thousands, except lease term and discount rate).

Information related to operating lease activity during the three months ended March 31, 2020 and 2019 was as follows (in thousands):

Future annual payments of operating lease liabilities as of ~~September 30, 2017.~~March 31, 2020 are as follows (in thousands):

The operating leases require the Company to ~~purchase $40.0 million~~share in ~~shares~~prorated operating expenses and property taxes based upon actual amounts incurred; those amounts are not fixed for future periods and, therefore, are not included in the future commitments listed above.

Property and equipment are stated at cost and depreciated using the straight-line method over the estimated useful lives of the ~~Company’s redeemable convertible preferred stock at~~assets, ranging from two to five years. Leasehold improvements are amortized over the ~~discounted price, which would have satisfied~~shorter of their estimated useful lives or the ~~$40.0 million obligation to purchase shares of~~related lease term. Upon retirement or sale, the ~~Company’s capital stock in connection with~~cost and related accumulated depreciation are removed from the continuation decision. Sanofi’s option to purchase $40.0 million of additional shares of the Company’s redeemable convertible preferred stock at the discounted price expired upon the closing of the Series B redeemable convertible preferred stock financing in April 2015.

The Company had determined that Sanofi’s right to purchase the redeemable convertible preferred stock at the discounted price, and the Company’s corresponding obligation to issue this additional redeemable convertible preferred stock, represented a freestanding financial instrument. The freestanding convertible preferred stock call option liability was initially recorded at its fair value of $0.7 million in 2014. The Company did not have a liability related to the redeemable convertible preferred stock call option on its consolidated balance sheet asand the resulting gain or loss is reflected in the consolidated statement of ~~September 30, 2017~~operations and ~~December 31, 2016.~~

5.~~Up to $45.0 million in-kind research and collaboration activities.~~ Sanofi can fund up to $45.0 million of pre-approved funding of research and collaboration activities. Since Sanofi will pay its vendors and personnel directly as per the Collaboration Agreement, the Company will not receive cash from Sanofi and therefore will not account for the funding of the in-kind services.comprehensive loss.

Depreciation expense was ~~$0.4~~$0.8 million and ~~$0.3~~$0.5 million for the three months ended ~~September 30, 2017~~March 31, 2020 and ~~2016, respectively, and $1.0 million and $0.8 million, for the nine months ended September 30, 2017 and 2016,~~2019, respectively.

The Company conducts product research and development programs through a combination of internal and collaborative programs that include, among others, arrangements with universities, contract research organizations and clinical research sites. The Company has contractual arrangements with these organizations; however, these contracts are generally cancelable on 30 days’ notice and the obligations under these contracts are largely based on services performed.

On June 29, 2012, the Company entered into a 66-month lease for approximately 12,000 square feet of office and laboratory space in South San Francisco with annual payments of approximately $0.5 million. In connection with this lease agreement, the Company also entered into a shared facilities and services agreement with Global Blood Therapeutics, Inc. (“GBT”), a co-tenant in the office building. In October 2014, the Company entered into a lease assignment agreement with the owner of the building and GBT to allow GBT to sublease the Company’s portion of the building beginning in March 2015. For the three and nine months ended September 30, 2017, the Company recorded approximately $0.1 million and $0.3 million, respectively, of sublease income and $0.1 million and $0.3 million, respectively, of sublease expense, which is recorded in interest and other income, net in the consolidated statements of operations and comprehensive loss. For the three and nine months ended September 30, 2016, the Company recorded approximately $0.1 million and $0.3 million, respectively, of sublease income and $0.1 million and $0.3 million, respectively, of sublease expense, which is recorded in interest and other income, net in the consolidated statements of operations and comprehensive loss.

On September 15, 2014, the Company entered into a five-year lease for approximately 34,400 square feet of office and laboratory space in South San Francisco. The Company may extend the lease for an additional three year term. The initial annual lease payments are $1.3 million, increasing to $1.6 million in the final year of the agreement. The lease period commenced in January 2015. The Company received a lease abatement for the first three months of the lease term, which is recorded as deferred rent and recognized over the lease term.

The Company has provided deposits for letters of credit totaling $0.3 million to secure its obligations under its leases, which have been classified as long-term assets on the Company’s consolidated balance sheet as of September 30, 2017.

~~Rent expense, net, was $0.3 million and $1.0 million, for each of the three and nine months ended September 30, 2017 and 2016, respectively.~~

From time to time, the Company may have contingent liabilities that arise in the ordinary course of business activities. The Company accrues for such ~~a liability~~liabilities when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. There were no0 contingent liabilities requiring accrual or disclosure as of ~~September 30, 2017,~~March 31, 2020 or December 31, ~~2016.~~2019.

The Company enters into standard indemnification arrangements in the ordinary course of business.

Pursuant to certain of these arrangements, the Company indemnifies, holds harmless and agrees to reimburse the indemnified parties for losses suffered or incurred by the indemnified party, in connection with any trade secret, copyright, patent or other intellectual property infringement claim by any third-party with respect to the Company’s technology. The term of these indemnification arrangements is generally perpetual. The maximum potential amount of future payments the Company could be required to make under these agreements is not determinable because it involves claims that may be made against the Company in the future but have not yet been made.

The Company indemnifies its officers and directors for certain events or occurrences, subject to certain limits, while the officer or director is or was serving at the Company’s request in such capacity, as permitted under Delaware law and in accordance with its certificate of incorporation and bylaws and agreements providing for indemnification entered into with its officers and directors. The term of the indemnification period lasts as long as an officer or director may be subject to any proceeding arising out of acts or omissions of such officer or director in such capacity.

The maximum amount of potential future indemnification of directors and officers is unlimited; however, the Company currently holds director and officer liability insurance. This insurance allows the transfer of risk associated with its exposure and may enable it to recover a portion of any future amounts paid.

The Company believes that the fair value of these indemnification obligations is minimal. Accordingly, the Company has not recognized any liabilities relating to these obligations for any period presented.

On January 3, 2020, the Company entered into a sales agreement with a sales agent to establish an at-the-market (ATM) offering program, under which the Company is permitted to offer and sell, from time to time, shares of common stock having a maximum aggregate offering price of up to $200 million. As of March 31, 2020, no securities have been issued pursuant to the ATM agreement.

In March 2019, the Company completed a follow-on offering and issued 5,663,750 shares of common stock at a price of $51.00 per share, which included 738,750 shares sold directly to the underwriters upon exercise of their over-allotment option. During the three months ended March 31, 2019, the Company received proceeds totaling approximately $271.2 million from the offering, net of underwriting discounts and commissions and offering expenses.

The Company classifies stock-based compensation expense in the accompanying condensed consolidated statements of operations and comprehensive loss based on the department to which a recipient belongs. The following table sets forth stock-based compensation expense related to ~~options~~equity awards granted to employees and consultants for all periods presented (in thousands):

The following summarizes option and other equity award activity under the 2012 Equity Incentive Plan and 2015 Stock Option and Incentive Plan:

Shares Subject to

Weighted Average

Outstanding
Options

Exercise Price
Per Share

Balance at December 31, 2016

2,141,868

$
6.42

Options granted

1,685,575

14.69

Options exercised

(282,978
)

4.46

Options canceled

(254,788
)

9.13

Balance at September 30, 2017

3,289,677

$
10.62

	Shares Subject to			Weighted Average
	Outstanding Options			Exercise Price per Share
Balance at December 31, 2019		4,574,158		$	31.81
Options granted		801,937			70.08
Options exercised		(107,870	)		16.88
Options canceled/forfeited		(27,486	)		44.50
Balance at March 31, 2020		5,240,739			37.91

	Shares Subject to			Weighted Average
	Outstanding Awards			Grant Date Fair Value
Balance at December 31, 2019		741,096		$	46.59
RSUs awarded		333,324			70.09
RSUs released		(125,243	)		43.19
RSUs forfeited		(8,004	)		47.68
Balance at March 31, 2020		941,173			55.36

Restricted stock units (“RSUs”) settle into shares of common stock upon vesting and the fair value is the market price on the date of grant.

In relation to stock options ~~to purchase common stock~~and awards that vest upon the achievement of performance criteria, ~~the Company recorded zero~~there was $0.3 million and ~~$174,000~~0 in stock-based compensation expense recorded for the three ~~and nine~~ months ended ~~September 30, 2017,~~March 31, 2020 and 2019, respectively ~~and $74,000 and~~ ~~$147,000~~ ~~for the three and nine months ended September 30, 2016, respectively~~. The Company begins to recognize expenses related to these stock options and awards during the period upon concluding that certain performance criteria are considered probable.

The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share amounts):

	Three Months Ended September 30,						Nine Months Ended September 30,						Three Months Ended March 31,
	2017			2016			2017			2016			2020			2019
Numerator
Net loss	$	(14,173	)	$	(9,231	)	$	(38,557	)	$	(27,411	)	$	(69,868	)	$	(37,470	)
Net loss attributable to common stockholders, basic and diluted	$	(14,173	)	$	(9,231	)	$	(38,557	)	$	(27,411	)
Denominator
Weighted average shares outstanding		33,686,799			27,023,650			32,195,471			27,023,951			46,566,995			40,512,983
Less: weighted average shares subject to repurchase		(161,232	)		(553,352	)		(243,840	)		(692,099	)		—			(6,670	)
Weighted average shares used to compute basic and diluted net loss per share		33,525,567			26,470,298			31,951,631			26,331,852			46,566,995			40,506,313
Net loss per share attributable to common stockholders, basic and diluted	$	(0.42	)	$	(0.35	)	$	(1.21	)	$	(1.04	)
Net loss per share, basic and diluted													$	(1.50	)	$	(0.93	)

The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because including them would have been antidilutive:

As of ~~September 30, 2017,~~March 31, 2020, the Company has contributions from plan participants of ~~$297,000~~$1.0 million under the 2015 ESPP, which if converted, would be equivalent to ~~25,668~~approximately 20,000 shares based on 85% of the stock price at the beginning of the offering period. As of March 31, 2019, the Company had contributions from plan participants of $0.7 million under the 2015 ESPP, which if converted, would have been equivalent to approximately 15,000 shares based on 85% of the stock price at the beginning of the offering period.

Deferred tax assets and deferred tax liabilities are determined based on temporary differences between the financial reporting and tax bases of ~~September 30, 2016,~~assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. A valuation allowance is recorded against deferred tax assets if it is more likely than not that some portion or all of the deferred tax assets will not be realized.

The Company does not recognize a tax benefit for uncertain tax positions unless it is more likely than not that the position will be sustained upon examination by tax authorities, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax benefit potentially recorded for these positions is measured at the largest amount of cumulative benefit that has greater than a 50 percent likelihood of being realized upon ultimate settlement. Deferred tax assets that do not meet these recognition criteria are not recorded and the Company ~~had contributions from plan participants~~recognizes a liability for uncertain tax positions that may result in tax payments. If such unrecognized tax benefits were realized and not subject to valuation allowances, the entire amount would impact the tax provision.

The Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) was enacted by the United States Congress on March 27, 2020. The Company has not participated in any provision of ~~$235,060~~the CARES Act to date and has decided not to apply for a loan under the ~~2015 ESPP, which if converted, would be equivalent to 24,148 shares based on 85%~~Paycheck Protection Program (“PPP”) component of ~~the stock price at the beginning of the offering period.~~

~~In September 2012, the Company began receiving consulting and management services pursuant to an unwritten agreement with Third Rock Ventures, which is one of~~this legislation. The CARES Act did not impact the Company’s ~~largest shareholders. Kevin Starr, a director of the Company, is a par~~tner of Third Rock Ventures. Charles Homcy, a former director who resigned from the Board of Directors in March 2017, is a venture partner of Third Rock Ventures. The consulting fees paid to Third Rock Ventures were incurred by the Company in the ordinary course of business, and were $12,000 and $45,000provision for income taxes or consolidated financial statements for the three ~~and nine~~ months ended ~~September 30, 2017, respectively, and $7,000 and $31,000 for the three and nine months ended September 30, 2016, respectively. As of September 30, 2017 and December~~March 31, ~~2016, the Company had outstanding obligations to Third Rock Ventures of $13,000 and $9,000, respectively.~~

~~The Company currently leases approximately 34,400 square feet of laboratory and office space in South San Francisco, California under a lease that expires on January 19,~~ 2020. On October 1, 2017, the Company entered into an additional 25-month sublease agreement for approximately 8,000 square feet of office space in South San Francisco with annual payments of approximately $0.3 million. The lease period commenced on October 1, 2017.

You should read the following management’s discussion and analysis of our financial condition and results of operations in conjunction with our unaudited condensed consolidated financial statements and notes thereto included in Part I, Item 1 of this Quarterly Report on Form 10-Q and with our audited consolidated financial statements and notes thereto for the year ended December 31, ~~2016,~~2019, included in our Annual Report on Form 10-K for the year ended December 31, ~~2016,~~2019, filed with the U.S. Securities and ~~Exchange~~Exchange Commission (SEC) on ~~March 13, 2017~~February 27, 2020 (the “Annual Report”).

This report contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those discussed in ~~the~~these forward-looking statements. The statements contained in this report that are not purely historical are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and Section 2 1E21E of the Securities Exchange Act of 1934, as amended (the “~~Exchange~~“Exchange Act”). Forward-looking statements are often identified by the use of words such as, but not limited to, “anticipate,” “believe,” “can,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “project,” “seek,” “should,” “strategy,” “target,” “will,” “would” and similar expressions or variations intended to identify forward-looking statements. These statements are based on the beliefs and assumptions of our management based on information currently available to management. Such forward-looking statements are subject to risks, uncertainties and other important factors that could cause actual results and the timing of certain events to differ materially from future results expressed or implied by such forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, those identified below and those discussed in the section titled “Risk Factors” included under Part II, Item 1A below. Furthermore, such forward-looking statements speak only as of the date of this report. Except as required by law, we undertake no obligation to update any forward-looking statements to reflect events or circumstances after the date of such statements.

We are a ~~clinical stage~~clinical-stage biopharmaceutical company pioneering a precision medicine approach to discover, develop and commercialize targeted therapies for the treatment of serious ~~and neglected rare~~ cardiovascular diseases. Our ~~initial focus~~goal is to be the world’s leading precision cardiovascular medicine company. Precision medicine involves discovering and developing therapies that integrate clinical and molecular information based on the ~~treatment~~biological basis of ~~heritable cardiomyopathies,~~disease. Our strategy is to identify homogenous subgroups of patients with a ~~group~~given cardiovascular disease, understand the causal factors underlying that subgroup’s condition and develop targeted therapies designed to correct the common underlying defect leading to abnormal cardiac contraction or relaxation within each subgroup.

Our lead clinical-stage candidate is mavacamten, a novel, oral, allosteric modulator of ~~rare, genetically-driven forms of heart failure that result from biomechanical defects in~~ cardiac muscle contraction. We have used our precision medicine platform to generate a robust pipeline of therapeutic programs for the chronic treatment of the two most common forms of heritable cardiomyopathy—hypertrophic cardiomyopathy, or HCM, and dilated cardiomyopathy, or DCM.

~~We have completed enrollment in a Phase 2 clinical trial of mavacamten (formerly known as MYK-461), our product candidate~~myosin being developed for the treatment of ~~HCM,~~hypertrophic cardiomyopathy (HCM). Mavacamten is intended to reduce cardiac muscle contractility by inhibiting the excessive myosin-actin cross-bridge formation that underlies the excessive contractility, left ventricular hypertrophy and ~~are currently enrolling subjects in a Phase 1 clinical trial~~reduced compliance characteristic of MYK-491, our product candidate for the treatment of DCM. Using our precision medicine development strategy, we believe we have efficiently generated clinical proof of mechanism for mavacamten in both healthy volunteers and in HCM patients, and we intend to pursue a similar path for MYK-491. HCM. In 2016, mavacamten was granted Orphan Drug Designation by the ~~U.S.~~United States Food and Drug Administration ~~or the FDA,~~(FDA) for the treatment of symptomatic obstructive ~~hypertrophic~~HCM. We are currently conducting a Phase 3 pivotal study of mavacamten, known as EXPLORER-HCM in patients with symptomatic obstructive (New York Heart Association Class II or III) HCM. Enrollment in the EXPLORER-HCM study completed in August 2019 at clinical sites in the United States, Europe, and Israel. Topline data from the EXPLORER-HCM study are anticipated in the second quarter of 2020. Pending the outcome of this study, we plan to file a New Drug Application seeking regulatory approval of mavacamten for the treatment of obstructive HCM.

In addition to the EXPLORER-HCM study of mavacamten, we are conducting a MAVA long-term extension (LTE) study of mavacamten in patients who have completed our Phase 3 EXPLORER-HCM study or the Phase 2 MAVERICK-HCM in non-obstructive HCM. To protect the safety of study participants, investigators and staff, and to ensure consistent and appropriate clinical trial conduct in light of the COVID-19 pandemic, we have temporarily suspended the rollover of patients from EXPLORER into the MAVA-LTE study and plan to resume enrollment when conditions permit.

MAVERICK-HCM is a Phase 2 clinical trial initiated in 2018 for the potential treatment of symptomatic non-obstructive HCM. In November 2019, we reported positive top-line results and established safety and tolerability of mavacamten in non-obstructive HCM over a treatment period of 16 weeks. Additional data were reported in March 2020. Meaningful reductions in biomarkers of cardiac stress were observed in patients receiving mavacamten versus those in the placebo cohort and clear signals of clinical benefit were noted in a subgroup with elevated cardiac filling pressures and in a pre-specified group of patients at higher risk for morbidity and mortality. Based on the safety and pharmacologic benefits observed in the MAVERICK-HCM study, we plan to advance mavacamten into additional studies in defined groups of patients with non-obstructive HCM and heart failure with preserved ejection fraction (HFpEF).

Patient enrollment in the VALOR-HCM study was previously planned to begin in the second quarter of 2020. In March of 2020 we announced that patient enrollment in the VALOR-HCM study would be delayed due to the global outbreak of COVID-19. The VALOR-HCM study is designed to evaluate mavacamten as a therapeutic alternative to septal reduction therapy (SRT) in obstructive HCM patients. SRT is a highly invasive procedure consisting of a surgical or catheter-based therapy that eliminates or reduces the left ventricular outflow tract obstruction. We will begin enrollment of the study when conditions safely permit.

We are also conducting PIONEER-OLE, an open label extension study of obstructive HCM patients from our Phase 2 PIONEER study. Data for twelve patients at 48 weeks of treatment with mavacamten were consistent with prior safety and efficacy observations at the 12, 24, and 36-week readouts. Highlights of the data included continued safety and tolerability and sustained clinical benefits, including reductions in left ventricular outflow tract (LVOT) gradient, improvements in New York Heart Association functional class and improvement of multiple biomarkers toward normal ranges. A reduction in septal wall thickness, a defining characteristic of HCM, as well as an improvement in patient reported quality of life, as measured by the Kansas City Cardiomyopathy Questionnaire were also reported.

Our second clinical-stage candidate is danicamtiv, designed to increase the contractility of the heart (systolic function) with minimal or no effect on myocardial relaxation and compliance (diastolic function) by acting directly on the proteins in the heart muscle responsible for contraction.

We recently announced interim results from a Phase 2a multiple-ascending dose clinical trial of danicamtiv, in patients with stable heart failure. This trial follows the completion of two single-ascending dose Phase 1 studies, in healthy volunteers and in patients with dilated cardiomyopathy, ~~(oHCM),~~ a ~~subset~~disease of ~~HCM.~~systolic dysfunction that can result in heart failure. After seven days of treatment with danicamtiv, the average increase in stroke volume, a measure of the amount of blood pumped from the left ventricle, was greater than 10% relative to baseline, on a placebo-adjusted basis. No impact on measures of diastolic function, or the heart’s ability to relax and fill, was observed. Patient enrollment into the Phase 2 study of danicamtiv in patients with genetic dilated cardiomyopathy was previously scheduled to begin in the second quarter of 2020. In March of 2020 we announced that patient enrollment into that study would be delayed due to the impact of COVID-19. We will begin enrollment when conditions safely permit.

In August 2019, we commenced dosing healthy volunteers in a Phase 1 study of small molecule MYK-224. The randomized, placebo-controlled Phase 1 study is designed to evaluate the safety, tolerability and pharmacokinetics of MYK-224. In March of 2020 we announced that due to the impact of COVID-19 we have temporarily suspended enrollment of healthy volunteers in the study. We plan to resume enrollment as soon as conditions safely permit.

The ultimate impacts of COVID-19 on our business are currently unknown. We will continue to actively monitor the situation and may take further precautionary and preemptive actions as may be required by federal, state or local authorities or that we determine are in the best interests of public health and safety and that of our patient community, employees, partners, suppliers and stockholders. We cannot predict the effects that such actions, or the impact of COVID-19 on global business operations and economic conditions may have on our business or strategy, including the effects on our ongoing and planned clinical development activities and prospects, or on our financial and operating results.

We have not generated net income from operations and, as of ~~September 30, 2017, we~~March 31, 2020, had an accumulated deficit of ~~$116.4~~$548.6 million, primarily as a result of research and development and selling, general and administrative expenses.

To date, all of our revenue has been derived from non-refundable payments under the license and collaboration agreement we entered into with Aventis Inc., a wholly-owned subsidiary of Sanofi S.A., in August 2014, which we refer to as the Collaboration Agreement, and we We have not ~~yet~~ generated any revenue from product ~~sales. We have never been profitable~~sales since our inception and have ~~incurred net losses~~funded our operations primarily through the issuance of equity securities and payments from Sanofi pursuant to our Collaboration Agreement with Sanofi that was terminated in ~~each year since commencement of our operations.~~December 2018. We expect to incur significant and increasing losses from operations for the foreseeable future and we can provide no assurance that we will ever generate significant revenue or profits.

~~Through September 30, 2017,~~ As of March 31, 2020, we have financed our operations through an IPO, two follow-on public offerings, private placements of redeemable convertible preferred stock and funds received in connection with the Collaboration Agreement with Aventis Inc., a wholly-owned subsidiary of Sanofi S.A., entered into in August 2014. Prior to our IPO, we received net proceeds of $93.9 million from the sale of shares of our Series A, A-1 and B redeemable convertible preferred stock. On November 3, 2015, we completed our IPO of 6,253,125 shares of common stock at an offering price of $10.00 per share, resulting in net proceeds of approximately $55.6 million, after deducting underwriting discounts, commissions and offering costs. On October 3, 2016, we completed a follow-on public offering of 4,370,000 shares of common stock at an offering price of $15.00 per share, resulting in net proceeds of approximately $61.1 million, after deducting underwriting discounts, commissions and estimated offering costs. On August 14, 2017, we completed another follow-on

public offering of 4,025,000 shares of common stock at an offering price of $35.50 per share, resulting in net proceeds of approximately $133.8 million, after deducting underwriting discounts, commissions and estimated offering costs. In connection with the Collaboration Agreement, we have received $105.0 million from Sanofi S.A., consisting of a $35.0 million upfront payment, a $25.0 million milestone payment for the submission of an investigational new drug application (“IND”), for MYK-491 with the FDA in November 2016, and a $45.0 million continuation payment from Sanofi in January 2017. ~~As of September 30, 2017, we had~~ cash and cash equivalents of ~~$227.2~~$131.2 million, short-term investments of ~~$20.0~~$218.8 million and long-term investments of ~~$36.0 million~~,$10.1 million.

On January 3, 2020, we entered into a sales agreement with a sales agent to establish an at-the-market (ATM) offering program, under which we ~~believe will be sufficient~~are permitted to ~~fund~~offer and sell, from time to time, shares of common stock having a maximum aggregate offering price of up to $200 million. As of March 31, 2020, no securities have been issued pursuant to the ATM agreement.

Until December 31, 2018 we had an exclusive Collaboration Agreement with Sanofi. On December 31, 2018, Sanofi notified us of its intent to terminate our ~~planned operations through at least the next twelve months.~~

~~We have no manufacturing facilities, and all of our manufacturing activities are contracted out to a third party. Additionally, we currently utilize third-party clinical research organizations (“CROs”) to carry out our clinical development and trials. We do~~collaboration, specifically, Sanofi elected not ~~yet have a sales organization.~~

We expect to incur substantial expenditures in the foreseeable future for the advancement of our precision medicine platform, the development and potential commercialization of mavacamten and MYK-491, and the discovery, development and potential commercialization of any additional product candidates we may pursue. Specifically, we expect to continue ~~to incur substantial expenses in connection~~ with ~~our ongoing PIONEER-HCM Phase 2 clinical trial~~the mavacamten, MYK-224 and danicamtiv programs. As a result, cost sharing and Sanofi’s reimbursement of ~~mavacamten and any additional Phase 2 and Phase 3 clinical trials that we may conduct for mavacamten, as well as~~ our ongoing and planned clinical development activities for MYK-491. We will need substantial additional funding to support our operating activities as we advance mavacamten, MYK-491, and other potential product candidates through clinical development, seek regulatory approval and prepare for, and if approved, proceed to commercialization. Adequate funding may not be available to us on acceptable terms, or at all.

~~The~~ research and development ~~expenses incurred~~costs for mavacamten and MYK-224 ended in the ~~development and potential commercialization~~first half of ~~mavacamten, MYK-491 and other product candidates are (in thousands):~~

~~In August 2014, we entered into the Collaboration Agreement with Aventis, Inc., a wholly-owned subsidiary of Sanofi S.A., that covers three main research programs: our first program in HCM (referred~~ had continuing rights to as mavacamten or HCM-1), a second program in HCM (referred to as HCM-2) and our first program in DCM (referred to as MYK-491 or DCM-1). For purposes of this filing, we refer to Sanofi as our co-party to the Collaboration Agreement.

Under the Collaboration Agreement, we are responsible for conducting research and development activities through early human efficacy studies, except for specified research activities to be conducted by Sanofi. Thereafter, we will lead worldwide development and U.S. commercial activities for the mavacamten and HCM-2 programs, Sanofi will lead global development and commercial activities for MYK-491 and Sanofi will lead commercial activities for the mavacamten and HCM-2 programs where it has ex-U.S. commercialization rights. Sanofi also has the option to co-promote the mavacamten and HCM-2 programs in the United States onlyroyalties in the event of a potential expanded cardiovascular disease indication outside of the genetically targeted indications for mavacamten and HCM-2. We have co-commercialization rights to MYK-491 in the United States, at our option.

We are entitled to receive tiered royalties ranging from the mid-single digits to the mid-teens on net sales of certain HCM and DCM finished products outside the United States and on net sales of certain DCM finished products in the United States. Sanofi is eligible to receive tiered royalties ranging from the mid-single digits to the low teens on our net sales of certain HCM finished products in the United States.commercialization

~~Under~~of the mavacamten and MYK-224 programs. In July 2019, we repurchased those rights from Sanofi for $80.0 million. Neither we nor Sanofi have any material continuing rights or obligations under the Collaboration Agreement, Sanofi also agreed to provide up to $200.0 million in upfront and milestone payments, equity investments and research and development support. As of September 30, 2017, of such amount, we have received from Sanofi an initial non-refundable upfront cash payment of $35.0 million and equity investments of $10.0 million in exchange for Series A-1 redeemable convertible preferred stock, and a $25.0 million milestone-based payment. In addition, we have received equity funding outside of the original agreement of $5.0 million in exchange for Series B redeemable convertible preferred stock and $9.0 million in exchange for shares of our common stock in our IPO. In January 2017, we also received a $45.0 million continuation payment. The total payments we were originally eligible to receive also included an obligation from Sanofi to purchase an additional $40.0 million of our capital stock if Sanofi provided notice of its intent to continue the collaboration prior to December 31, 2016. Under the Collaboration Agreement, Sanofi’s obligation to purchase the additional $40.0 million of our capital stock (which was reduced by $5.0 million for its purchase of the Series B redeemable convertible preferred stock) ~~terminated in connection with~~ ~~the closing of~~ ~~our IPO in~~ ~~November 2015. Additionally, we are eligible to receive up to $45.0 million of approved in-kind research and clinical activities.~~

This discussion and analysis of our financial condition and results of operations is based on our consolidated financial statements, which have been prepared in accordance with U.S. generally accepted accounting principles. The preparation of these consolidated financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, as well as the reported expenses incurred during the reporting periods. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

Our significant accounting policies are fully described in Note 2 of our Annual Report. We believe that the accounting policies discussed in our Annual Report are critical to understanding our historical and future performance, as these policies relate to the more significant areas involving management’s judgments and estimates. There have been no changes to our significant accounting policies during the nine months ended September 30, 2017, except with respect to changes in our policy on Stock-Based Compensation. As permitted under ASU 2016-09, we have elected to recognize forfeitures as they occur, and no longer estimate a forfeiture rate when calculating the stock-based compensation for our equity awards.Agreement.

~~We generate revenue from the Collaboration Agreement with Sanofi for the development and commercialization of products under the collaboration.~~

Research and development expenses consist of salaries and benefits, including stock-based compensation, lab supplies and facility costs ~~as well as~~and fees paid to ~~CROs~~contract manufacturing organizations (CMOs) and clinical research organizations (CROs) to conduct certain research and development activities on our behalf. ~~Amounts incurred in connection with collaboration~~Research and ~~license agreements~~development expenses are ~~also included in~~shown net of amounts that Sanofi agreed to reimburse us under the cost sharing program for research and development ~~expense.~~activities. Payments made prior to ~~third parties in advance~~the receipt of ~~the performance of the related~~goods or services ~~by the third parties~~ are ~~recorded as prepaid expenses~~capitalized until the goods or services are ~~rendered.~~received.

Research and development expenses incurred in the development and potential commercialization of mavacamten, danicamtiv and other product candidates are shown net of zero and $9.9 million in reductions in expense due to Sanofi research and development reimbursements during the three months ended March 31, 2020 and 2019, respectively as follows (in thousands):

~~General~~Selling, general and administrative expenses consist principally of ~~personnel-related costs,~~salaries and benefits, including stock-based compensation, professional fees for legal, consulting, audit and tax services, market research, rent and other general operating expenses not otherwise classified as research and development expenses.

Interest and other income, net consists primarily of interest income earned on our cash and cash equivalents, short-term investments and long-term investments.

See Part I, Item 7, “Critical Accounting Estimates” in our Annual Report. There have been no material changes to our critical accounting estimates disclosed in our Annual Report.

Comparison of the ~~Three-Month Periods~~Three Months Ended ~~September 30, 2017~~March 31, 2020 and ~~2016~~2019

	Three Months Ended September 30,						Increase		Three Months Ended March 31,						Change
	2017			2016			(Decrease)		2020			2019			$			%
	(in thousands)
Collaboration and license revenue	$	5,625		$	3,550		$	2,075
Operating expenses:
Research and development		14,361			8,783			5,578		51,878			26,190			25,688			98	%
General and administrative		5,884			4,031			1,853
Selling, general and administrative										19,902			13,551			6,351			47	%
Total operating expenses		20,245			12,814			7,431		71,780			39,741			32,039			81	%
Loss from operations		(14,620	)		(9,264	)		5,356		(71,780	)		(39,741	)		(32,039	)		81	%
Interest and other income, net		447			33			414		1,912			2,271			(359	)		-16	%
Net loss and comprehensive loss	$	(14,173	)	$	(9,231	)	$	4,942
Net loss									$	(69,868	)	$	(37,470	)	$	(32,398	)		86	%

Collaboration and license revenue increased $2.1 million, or 58%, from the $3.6 million during the three months ended September 30, 2016 to $5.6 million for the three months ended September 30, 2017. The amount for the period ended September 30, 2016 relates to revenue we recognized from the initial upfront payment of $35.0 million under the Collaboration Agreement with Sanofi. The amount for the period ended September 30, 2017 relates to revenue we recognized from the continuation payment of $45.0 million under the Collaboration Agreement.* Not meaningful

Research and development expenses increased ~~$5.6~~$25.7 million, or ~~64%~~98%, from ~~$8.8~~$26.2 million for the three months ended ~~September 30, 2016~~March 31, 2019 to ~~$14.4~~$51.9 million for the three months ended ~~September 30, 2017.~~March 31, 2020. The increase in research and development expenses was primarily due to a $1.3 million increase in personnel expenses as a result of an increase in employee headcount, a $1.1 million increase in contract research, chemistry and biology expenses on discovery and pre-clinical programs including HCM-2 and a back-up program for DCM-1, a $3.2 million increase in clinical expenses for mavacamten and MYK-491 clinical trials, and a $0.4 million increase in stock compensation expense.

~~We expect research and development expenses to increase in future periods as we continue~~ the development of our lead product candidate, mavacamten, in clinical trials as well as preclinical and subsequent clinical activities for our MYK-491, HCM-2, additional mechanisms within DCM, and other back-up programs. As product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials, we expect that our research and development expenses will increase substantially in the future.following:

~~General~~Selling, general and administrative expenses increased ~~$1.9~~$6.4 million, or ~~46%~~47%, from ~~$4.0~~$13.6 million for the three months ended ~~September 30, 2016~~March 31, 2019 to ~~$5.9~~$19.9 million for the three months ended ~~September 30, 2017.~~March 31, 2020. The increase in selling, general and administrative expenses was primarily due to a $0.2 million increase in personnel expenses as a result of an increase in employee headcount, increases of $0.2 million in office and related expenses, $0.4 million in marketing expense, $0.5 million in professional and consulting expense, $0.4 million in recruiting expense, and a $0.4 million increase in stock compensation expense as we expanded our operations.

~~We expect general and administrative expenses to continue to increase in future periods, reflecting both~~ the increased costs in connection with the continued clinical development and potential future commercialization of mavacamten, the ongoing and planned clinical development of MYK-491, as well as an expanded infrastructure and increased professional fees.following:

Interest and other income ~~increased $414,000~~decreased $0.4 million, or ~~1255%~~16%, from ~~$33,000~~$2.3 million for the three months ended ~~September 30, 2016~~March 31, 2019 to ~~$447,000~~$1.9 million for the ~~period ending September 30, 2017.~~three months ended March 31, 2020. The ~~increase~~decrease in interest income was primarily due to interest earned on lower invested balances and lower interest rates on investments.

Nine Months Ended
September 30,

Increase

2017

2016

(Decrease)

(in thousands)

Collaboration and license revenue

$
16,875

$
10,649

$
6,226

Operating expenses:

Research and development

39,967

26,192

13,775

General and administrative

16,442

11,947

4,495

Total operating expenses

56,409

38,139

18,270

Loss from operations

(39,534
)

(27,490
)

12,044

Interest and other income, net

977

79

898

Net loss and comprehensive loss

$
(38,557
)

$
(27,411
)

$
11,146

Collaboration and license revenue increased $6.2 million, or 58%, from the $10.7 million during the nine months ended September 30, 2016 to $16.9 million for the nine months ended September 30, 2017. The amount for the period ended September 30, 2016 relates to revenue we recognized from the initial upfront payment of $35.0 million under the Collaboration Agreement with Sanofi. The amount for the period ended September 30, 2017 relates to revenue we recognized from the continuation payment of $45.0 million under the Collaboration Agreement.

Research and development expenses increased $13.8 million, or 53%, from $26.2 million for the nine months ended September 30, 2016 to $40.0 million for the nine months ended September 30, 2017. The increase in research and development expenses was primarily due to a $3.9 million increase in personnel expenses as a result of an increase in employee headcount, a $3.6 million increase in contract research, chemistry and biology expenses on discovery and pre-clinical programs including HCM-2 and a back-up program for DCM-1, $5.9 million increase in clinical expenses for mavacamten and MYK-491 clinical trials, and a $1.2 million increase in stock compensation expense.

We expect research and development expenses to increase in future periods as we continue the development of our lead product candidate, mavacamten, in clinical trials as well as preclinical and subsequent clinical activities for our MYK-491, HCM-2, additional mechanisms within DCM, and other back-up programs. As product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials, we expect that our research and development expenses will increase substantially in the future.

General and administrative expenses increased $4.5 million, or 38%, from $12.0 million for the nine months ended September 30, 2016 to $16.5 million for the nine months ended September 30, 2017. The increase in general and administrative expenses was primarily due to a $0.7 million increase in personnel expenses as a result of an increase in employee headcount, increase of $0.6 million in office and related expenses, $1.0 million in marketing, $0.7 million in professional and consulting expense, and a $1.3 million increase in stock-compensation expense as we expanded our operations.

We expect general and administrative expenses to continue to increase in future periods, reflecting both the increased costs in connection with the continued clinical development and potential future commercialization of mavacamten, the ongoing and planned clinical development of MYK-491, as well as an expanded infrastructure and increased professional fees.

Interest and other income increased $898,000 or 1137%, from $79,000 for the nine months ended September 30, 2016 to $977,000 for the nine months ending September 30, 2017. The increase in interest income was primarily due to investments.

We consider the following when assessing our liquidity and capital resources (in thousands):

Since ~~our~~ inception, we have ~~financed~~funded our operations primarily through ~~private placements~~the issuance of our equity securities and payments ~~received in connection with~~from Sanofi pursuant to the Collaboration Agreement, which was terminated in December 2018. All our investments are in investment-grade securities.

On January 3, 2020, we entered into a sales agreement with a sales agent to establish an at-the-market (ATM) offering program, under which we are permitted to offer and ~~our public offerings~~sell, from time to time, shares of common ~~stock. During 2014,~~stock having a maximum aggregate offering price of up to $200 million. As of March 31, 2020, no securities have been issued pursuant to the ATM agreement.

In March 2019, we completed a follow-on offering in which we issued 5,663,750 shares of our common stock at a price of $51.00 per share, including 738,750 shares sold directly to the underwriters upon exercise of their option to purchase up to 738,750 shares of our common stock within 30 days of the offering. We received ~~net~~ proceeds ~~of $28.9~~totaling approximately $271.2 million from the sale of Series A and Series A-1 redeemable convertible preferred stock and, in August 2014, we received an upfront payment of $35.0 million from Sanofi in connection with the entry into the Collaboration Agreement. In April 2015, we received net proceeds of $45.8 million from the sale of Series B redeemable convertible preferred stock. Pursuant to the IPO in November 2015, we received net proceeds of $55.6 million,offering, net of underwriting discounts, commissions and offering costs. On October 3, 2016, we completed a follow-on public offering of 4,370,000 shares of common stock at an offering price of $15.00 per share, resulting in net proceeds of approximately $61.1 million, after deducting underwriting discounts, commissions and estimated offering costs. On August 14, 2017, the Company completed another follow-on public offering of 4,025,000 shares of common stock at an offering price of $35.50 per share, resulting in net proceeds of approximately $133.8 million, after deducting underwriting discounts, commissions and estimated offering costs. In connection with the Collaboration Agreement,expenses.

We believe we have ~~received $60.0 million from Sanofi S.A., consisting of a $35.0 million upfront payment, and a $25.0 million payment~~sufficient financial resources to meet our business requirements for the submission of an IND for MYK-491 with the FDA in November 2016. In addition, we received a $45.0 million continuation payment from Sanofi in January 2017 in connection with Sanofi’s decision in December 2016 to extend the collaboration term. ~~As of September 30, 2017, we had cash and cash equivalents of $227.2 million,~~ ~~short-term investments of $20.0 million and long-term investments of $36.0 million, which we believe will be sufficient to fund our planned operations through at least the next twelve months.~~

To date, we have not generated any revenue from product sales. We do not know when, or if, we will generate any revenue from product sales and do not expect to generate significant revenue from product sales unless and until we obtain regulatory approval of and commercialize mavacamten, MYK-491 or other product candidates.

~~We expect that our existing cash and cash equivalents will provide sufficient funds to sustain operations through at least the next~~ 12 months ~~based~~following the date of this Quarterly Report on ~~our existing business plan. However, we~~Form 10-Q. We expect to incur substantial expenditures in the foreseeable future for the advancement of our precision medicine platform, the development and potential commercialization of ~~mavacamten and MYK-491,~~our product candidates and the discovery, development and potential commercialization of any additional product candidates we may pursue. Specifically, we have incurred substantial expenses in connection with our Phase 1 clinical trials of mavacamten and expect to continue to incur substantial expenses in connection with our ongoing PIONEER-HCM Phase 2 clinical trial of mavacamten and any additional Phase 2 and Phase 3 clinical trials that we may conduct for mavacamten, as well as our ongoing and planned clinical development activities for MYK-491. Furthermore, if our ~~planned Phase 2 and potential Phase 3~~ clinical trials for mavacamten are successful, or our other product candidates, including ~~MYK-491,~~danicamtiv, enter into ~~later stage~~late-stage clinical trials or more advanced discovery and development stages, we ~~will~~may need to raise additional capital in order to further advance our product candidates towards regulatory approval.

We will continue to ~~require~~seek additional financing to develop our product candidates and fund operations for the foreseeable future through equity or debt financings, collaborative or other arrangements with corporate sources, or through other sources of financing. Adequate additional funding may not be available to us on acceptable terms or at all. Our failure to raise capital as and when needed could have a negative impact on our financial condition and our ability to pursue our business strategies. We anticipate that we will need to raise substantial additional capital, the requirements of which will depend on many factors, including:

~~We may seek funds through borrowings or additional rounds of financing, including private or public equity or debt offerings and collaborative arrangements with corporate partners.~~ If we raise additional funds by issuing equity securities, our stockholders may experience dilution. Any ~~future~~ debt financing into which we enter may impose upon us additional covenants that restrict our operations, including limitations on our ability to incur liens or additional debt, pay dividends, repurchase our common stock, make certain investments and engage in certain merger, consolidation or asset sale transactions. Any debt financing or additional equity that we raise may contain terms that are not favorable to us or our stockholders. If we are unable to raise additional funds when needed, we may be required to delay, reduce, or terminate some or all of our development programs and clinical trials. We may also be required to sell or license to ~~others~~other technologies, product candidates or programs that we would prefer to develop and commercialize ourselves.

The following table sets forth the primary sources and uses of cash for each of the periods presented below (in thousands):

Net cash used in operating activities for the ~~nine~~three months ended ~~September 30, 2017~~March 31, 2020 was $3.2 million, and was primarily due to the $45.0 million continuation payment received from Sanofi, partially offset by the net loss for the period of $38.6 million and a decrease in deferred revenue of $16.9 million, stock-based compensation expense of $4.3 million, and changes in operating assets and liabilities, including, an increase in accrued liabilities of $2.0 million.

~~Net cash used in operating activities for the nine months ended September 30, 2016 was $34.4~~$59.9 million and was primarily due to the net loss for the period ~~partially offset by~~of $69.9 million, adjusted for non-cash stock-based compensation expense of ~~$1.8~~$10.8 million and depreciation ~~expense~~ of $0.8 million, ~~and was also affected~~offset by ~~changes~~amortization of discount on investment of $0.4 million. Changes in ~~operating assets and liabilities, including a decrease in deferred revenue~~working capital primarily consisted of ~~$10.6~~decreases of $1.5 million ~~and an increase~~ in accrued liabilities and $0.5 million in accounts payable, offset by a decrease of ~~$1.0~~$0.2 million in prepaid expenses.

Net cash used in operating activities for the three months ended March 31, 2019 was $38.0 million and was primarily due to the net loss for the period of $37.5 million, adjusted for non-cash stock-based compensation expense of $7.0 million and depreciation of $0.5 million, offset by amortization of discount on investment of $0.3 million. Changes in working capital primarily consisted of a $9.9 million decrease in prepayments from our collaboration partner, a $2.0 million increase in accounts payable and a $0.7 million decrease in other long-term liabilities.

Cash provided by investing activities for the three months ended March 31, 2020 was $87.9 million and consisted primarily of sales and maturities of investments of $4.0 million and $96.5 million, respectively, offset by cash outflows of $12.6 million for leasehold improvements and purchases of equipment related to the occupancy of our new corporate headquarters in Brisbane, California in January 2020.

Cash used in investing activities for the ~~nine~~three months ended ~~September 30, 2017~~March 31, 2019 was $13.5 million and consisted primarily of purchases of investments of ~~$44.0~~$32.7 million and purchases of equipment of $0.8 million, offset by ~~sale~~sales and maturities of investments of $4.0 ~~million. During the nine months ended September 30, 2017~~million and ~~2016, we also had investments in equipment of $0.9 million.~~$16.0 million, respectively.

Cash provided by financing activities for the ~~nine~~three months ended ~~September 30, 2017~~March 31, 2020 was $1.8 million and consisted of ~~net~~proceeds from common stock option exercises.

Cash provided by financing activities for the three months ended March 31, 2019 was $271.8 million and consisted of proceeds from the issuance of common stock in connection with a follow-on offering of ~~$133.9~~$271.5 million, net of underwriter’s discount and funds received as a result of common stock option ~~exercise~~exercises of ~~$1.7~~$0.3 million.

Cash provided by financing activities in the nine months ended September 30, 2016 consisted of proceeds from the issuance of common stock in connection with purchases pursuant to the 2015 ESPP of $0.2 million, offset by payments of $0.2 million in deferred offering costs.

There have been no material changes ~~outside the ordinary course of our business~~ to our contractual obligations during the ~~nine~~three months ended ~~September 30, 2017,~~March 31, 2020, as compared to those disclosed in our Annual Report.

~~We do~~Since our inception, we have not ~~have~~engaged in any off-balance sheet arrangements, as defined in the rules and regulations of the SEC.

~~The Jumpstart Our Business Startups Act of 2012 (the “~~JOBS Act”), permits an “emerging growth company” such as us to take advantage of an extended transition period to comply with new or revised accounting standards applicable to public companies. We have elected to “opt out” of this provision and, as a result, we will comply with new or revised accounting standards as required when they are adopted. This decision to opt out of the extended transition period under the JOBS Act is irrevoca~~ble. See Note 2, Summary of Significant Accounting Policies, to our consolidated financial statements appearing in our Annual Report regarding recent accounting pronouncements.~~

The market risk inherent in our financial instruments represents the potential loss arising from adverse changes in interest rates or exchange rates. As of ~~September 30, 2017,~~March 31, 2020, we had cash, ~~and~~ cash equivalents and investments (short-term and long-term) of ~~$227.2~~$360.1 million, consisting of interest-bearing money market accounts ~~short-term investments of $20.0 million, consisting of corporate securities,~~ and ~~long-term investments of $36.0 million, consisting of United States government agency obligations,~~money market funds, which would be affected by changes in the general level of United States interest rates. However, due to the short-term maturities of our cash and cash equivalents and the low- risk profile of our investments, an immediate 100 basis point change in interest rates would not have a material effect on the fair value of our cash, ~~and~~ cash ~~equivalents.~~equivalents or investments.

In addition, we are also exposed to foreign currency exchange rate risk inherent in our contracts with research institutions and contract research organizations as certain services are performed by them outside the United States. We have payments due to one Australian vendor in foreign currency. A significant movement in the Australian dollar may have a material impact on our financial position in the future.

We do not believe that inflation, interest rate changes or exchange rate fluctuations had a significant impact on our results of operations for any periods presented.

The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the Exchange Act), refers to controls and procedures that are designed to ~~ensure~~provide reasonable assurance that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ~~ensure~~provide reasonable assurance that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure. Our management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and our management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Our disclosure controls and procedures are designed to provide reasonable assurance of achieving their control objectives.

Our management, with the participation of our Chief Executive Officer and ~~Senior Vice President, Finance and Corporate Development,~~Chief Financial Officer, has evaluated the effectiveness of our disclosure controls and procedures as of ~~September 30, 2017,~~March 31, 2020, the end of the period covered by this Quarterly Report on Form 10-Q. Based upon such evaluation, our Chief Executive Officer and ~~Senior Vice President, Finance~~Principal Financial and ~~Corporate Development~~Accounting Officer have concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of such date.

There was no change in our internal control over financial reporting that occurred during the period covered by this Quarterly Report on Form 10-Q that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

We are not currently a party to any material litigation or other material legal proceedings.

You should consider carefully the following risk factors, together with all the other information in this report, including our consolidated financial statements and notes thereto, and in our other public filings with the SEC. The occurrence of any of the following risks could harm our business, financial condition, results of operations and/or growth prospects or cause our actual results to differ materially from those contained in forward-looking statements we have made in this report and those we may make from time to time. You should consider all of the risk factors described when evaluating our business.

Risks Related to Our Precision Medicine Platform and the Discovery and Development of Our Product Candidates

The precision medicine approach we are taking to discover and develop drugs for serious diseases of systolic or diastolic dysfunction is novel and may never lead to marketable products.

We have concentrated our therapeutic product research and development efforts on the application of precision medicine to the treatment of cardiovascular diseases, and our future success depends on the successful development of products based on our precision medicine platform and the continued development of this platform. We believe we are the first company to apply precision medicine to the treatment of cardiovascular disease, and neither we nor any other company has received regulatory approval to market therapeutics specifically targeting the underlying cause of cardiomyopathy. The scientific discoveries that form the basis for our efforts to discover and develop product candidates are novel, and the scientific evidence to support the feasibility of developing product candidates based on these discoveries is both preliminary and limited. If we do not successfully develop and commercialize product candidates based upon our technological approach, we will not become profitable and the value of our common stock may decline.

Further, our focus, which has been solely on precision medicine for the development of drugs for diseases of cardiac muscle contraction as opposed to multiple, more proven technologies for drug development, increases the risks associated with the ownership of our common stock. If we are not successful in developing any product candidates using our precision medicine platform, we may be required to change the scope and direction of our product development activities. In that case, we may not be able to identify and implement successfully an alternative product development strategy, which would materially and adversely affect our business, financial condition and results of operations.

We depend heavily on the success of mavacamten, danicamtiv and MYK-224, our initial product candidates. Other than mavacamten, danicamtiv and MYK-224, all of our other programs are in discovery or preclinical development. Preclinical testing and clinical trials of our product candidates may not be successful. If we are unable to commercialize our product candidates or experience significant delays in doing so, our business will be materially harmed.

We have invested a significant portion of our efforts and financial resources in the identification of our initial product candidates, mavacamten and MYK-224 for the treatment of hypertrophic cardiomyopathy (HCM) and danicamtiv for the treatment of dilated cardiomyopathy (DCM). We are currently evaluating mavacamten, danicamtiv and MYK-224 in clinical trials, and, if these product candidates fail to demonstrate safety or efficacy in their respective target indications to the satisfaction of the FDA or other comparable regulatory authorities, we will need to identify and rely on other product candidates or target indications, or both, for clinical development. All of our other programs are still in discovery or preclinical development. Our ability to generate revenue from product sales, which we do not expect will occur for years, if ever, will depend heavily on the successful development and eventual commercialization of mavacamten, danicamtiv, MYK-224 or other product candidates that we may identify from our precision medicine platform.

The success of mavacamten, danicamtiv, MYK-224 and any other product candidates that we discover and develop will depend on many factors, including the following:

If we do not achieve one or more of these factors in a timely manner or at all, we could experience significant delays or an inability to successfully commercialize our product candidates, which would materially harm our business.

Preclinical and clinical drug development involves a lengthy and expensive process with an uncertain outcome, and observations and results from earlier studies and trials may not be applicable or predictive in future clinical trials.

Preclinical and clinical testing is expensive and can take many years to complete, and its outcome is inherently uncertain. Failure can occur at any time during the preclinical development or clinical trial process. The results of preclinical studies and early clinical trials of our product candidates may not be predictive of the results of later-stage clinical trials. For example, although our preclinical observations and data generated from our Phase 1 and Phase 2 clinical trials of mavacamten support our hypothesis that mavacamten has the potential to reduce cardiac muscle contractility and our belief that such data have demonstrated clinical proof of mechanism in both HCM patients and healthy volunteers, we have not completed placebo controlled clinical trials of mavacamten in larger populations using the current dosing strategy, inclusion/exclusion criteria, and endpoints of EXPLORER-HCM. In addition, our precision medicine platform is based on a translational medicine approach. Translational medicine, or the application of basic scientific findings to develop therapeutics that promote human health, is subject to a number of inherent risks. In particular, scientific hypotheses formed from preclinical or early clinical observations may prove to be incorrect, and the data generated in animal models or observed in limited patient populations may be of limited value and may not be applicable in clinical trials conducted under the controlled conditions required by applicable regulatory requirements and our protocols. The initial clinical data from our Phase 1 and Phase 2 clinical trials of mavacamten, as well as our Phase 1 and 2 clinical trials of danicamtiv, are preliminary in nature, and the clinical development of mavacamten and danicamtiv is not complete. Early positive data may not be repeated or observed in ongoing or future trials involving our product candidates. Product candidates in later stages of clinical trials may fail to show the desired safety and efficacy traits despite having progressed through preclinical studies and initial clinical trials. There is a high failure rate for drugs and biologics proceeding through clinical trials, particularly in the field of cardiovascular medicine. A number of companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in clinical development even after achieving promising results in earlier studies, and any such setbacks in our clinical development could have a material adverse effect on our business and operating results.

We may encounter substantial delays in our clinical trials or we may fail to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities.

Before obtaining marketing approval from regulatory authorities for the sale of our product candidates, we must conduct extensive clinical trials to demonstrate the safety and efficacy of the product candidates in humans. Clinical testing is expensive, time-consuming and uncertain as to outcome. We cannot guarantee that any clinical trials will be conducted as planned or completed on schedule, if at all. A failure of one or more clinical trials can occur at any stage of testing. We may experience delays in our ongoing clinical trials and we do not know whether planned clinical trials will begin on time, need to be redesigned, enroll patients on time or be completed on schedule, if at all. Additionally, although we believe that our precision medicine approach should eliminate the need for mavacamten to undergo the large outcomes-based studies that are often required for cardiovascular drugs as a condition to regulatory approval by the FDA or other regulatory authorities, regulatory authorities may nevertheless require us to conduct additional trials or generate additional data, including potential trials studying the interaction of our product candidates with other therapeutics commonly administered in the patient populations we are seeking to treat, which would increase the time and cost of our

clinical development process. Furthermore, we will need to conduct larger clinical trials, and the FDA may subsequently require us to evaluate a larger number of patients than we presently anticipate, or to assess other endpoints besides those presently contemplated, in order to support regulatory approval.

We could encounter delays if a clinical trial is suspended or terminated by us, by the IRBs of the institutions in which such trials are being conducted, or suspension or termination is recommended by the Data Safety Monitoring Board for such trial or by the FDA or other regulatory authorities. Such authorities may impose such a suspension or termination due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a drug, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial.

Moreover, principal investigators for our clinical trials may serve as scientific advisors or consultants to us from time to time and receive compensation in connection with such services. Under certain circumstances, we may be required to report some of these relationships to the FDA or other regulatory authorities. The FDA or other regulatory authorities may conclude that a financial relationship between us and a principal investigator has created a conflict of interest or otherwise affected interpretation of the study. The FDA or other regulatory authorities may therefore question the integrity of the data generated at the applicable clinical trial site and the utility of the clinical trial itself may be jeopardized. This could result in a delay in approval, or rejection, of our marketing applications by the FDA or other regulatory authorities, as the case may be, and may ultimately lead to the denial of marketing approval of one or more of our product candidates.

Any inability to successfully complete preclinical and clinical development could result in additional costs to us or impair our ability to generate revenues from product sales, and, if applicable under any collaboration or similar agreement, regulatory and commercialization milestones and royalties. In addition, if we make manufacturing or formulation changes to our product candidates, we may need to conduct additional studies to bridge our modified product candidates to earlier versions. Clinical trial delays could also shorten any periods during which we may have the exclusive right to commercialize our product candidates or allow our competitors to bring products to market before we do, which could impair our ability to successfully commercialize our product candidates and may harm our business and results of operations. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates.

If the results of our clinical trials are inconclusive or if there are safety concerns or adverse events associated with our product candidates, we may:

We may find it difficult to enroll patients in our clinical trials, which could delay or prevent clinical trials of our product candidates.

Identifying and qualifying patients to participate in clinical trials of our product candidates is critical to our success. The timing to commence and complete our clinical trials depends on the speed at which we can recruit patients to participate in testing our product candidates. If patients are unwilling to participate in our clinical trials because of a lack of familiarity with our approach to the treatment of cardiovascular diseases, negative publicity from adverse events in biotechnology or the fields of precision medicine or cardiovascular disease or for other reasons, including competitive clinical trials for similar patient populations, our timelines for recruiting patients, conducting clinical trials and obtaining regulatory approval of potential products may be delayed. These delays could result in increased costs, delays in advancing our product development, delays in testing the effectiveness of our product candidates or termination of our clinical trials altogether.

We may not be able to identify, recruit and enroll a sufficient number of patients, or those with required or desired characteristics to achieve diversity in a study, to complete our clinical trials in a timely manner. Patient enrollment is affected by factors including:

In particular, each of the conditions in which we are evaluating or plan to evaluate our product candidates are rare genetic disorders or involve segmented patient populations with limited patient pools from which to draw for clinical trials. To date, the HCM and DCM patient populations have not been extensively evaluated in clinical trials. As a result, enrollment in our ongoing and planned clinical trials is difficult to predict and may take longer or cost more than we anticipate.

We plan to seek initial marketing approval in the United States. We may not be able to initiate or continue clinical trials if we cannot enroll a sufficient number of eligible patients to participate in the clinical trials required by the FDA or other regulatory agencies. Our ability to successfully initiate, enroll and complete a clinical trial in any foreign country is subject to numerous risks unique to conducting business in foreign countries, including:

If we have difficulty enrolling a sufficient number of patients to conduct our clinical trials as planned, we may need to delay, limit or terminate ongoing or planned clinical trials, any of which would have an adverse effect on our business.

We may not be successful in our efforts to identify or discover potential product candidates.

The success of our business depends primarily upon our ability to identify, develop and commercialize therapeutics for the treatment of cardiovascular diseases based on our precision medicine approach. A key element of our initial strategy is to use our precision medicine platform to identify and study compounds that can be used to correct or offset the abnormal contraction caused by HCM and DCM. Our research programs may initially show promise in identifying potential product candidates, yet fail to yield product candidates for clinical development for a number of reasons, including:

If we are unable to identify suitable compounds for preclinical and clinical development, we may be forced to abandon our development efforts for a research program or programs and we will not be able to obtain product revenues in future periods, which likely would result in significant harm to our financial position and adversely impact our stock price.

Any of our product candidates may cause adverse effects or have other properties that could delay or prevent their regulatory approval, limit the scope of any approved label or market acceptance or result in other significant negative consequences following marketing approval, if any.

We have observed adverse events in our clinical trials of mavacamten. Results of our ongoing and planned trials could reveal a high and unacceptable severity and prevalence of these or other adverse events in subjects treated with our product candidates. Additionally, if the adverse events we have observed are deemed to be unacceptable or other unacceptable side effects or safety signals are observed in any ongoing or subsequent preclinical studies or clinical trials of our product candidates, our trials could be suspended or terminated and the FDA or comparable foreign regulatory authorities could order us to cease further development of or deny approval of our product candidates for any or all targeted indications. Any adverse effects encountered in our preclinical studies or clinical trials, whether or not drug-related, could affect patient recruitment or the ability of enrolled patients to complete the trial or result in potential product liability claims. Additionally, adverse effects may represent safety signals that could influence the benefit-risk assessment for further development or commercialization of a product candidate and may warrant further clinical or nonclinical investigation, consultation with health authorities, changes to product labeling or guidelines for its safe use, or other scientific or regulatory actions. Any of these occurrences may harm our business, financial condition and prospects significantly.

Further, if any of our future products, if and when approved for commercial sale, cause serious or unexpected adverse events, a number of potentially significant negative consequences could result, including:

Any of these events could prevent us or our partners from achieving or maintaining market acceptance of the affected product and could substantially increase the costs of commercializing our future products and impair our ability to generate revenues from the commercialization of these products.

We currently do not have regulatory approval to market any of our product candidates. The regulatory approval processes of the FDA and comparable foreign authorities are lengthy, time consuming and inherently unpredictable, and if we are ultimately unable to obtain regulatory approval for our product candidates, our business will be substantially harmed.

The time required to obtain approval by the FDA, EMA and comparable foreign authorities is unpredictable but typically takes many years following the commencement of clinical trials and depends upon numerous factors, including the substantial discretion of the regulatory authorities. In addition, approval policies, regulations, or the type and amount of clinical data necessary to gain approval may change during the course of a product candidate’s clinical development and may vary among jurisdictions. We have not obtained regulatory approval for any product candidate and it is possible that none of our existing product candidates or any product candidates we may seek to develop in the future will ever obtain regulatory approval.

Our product candidates could fail to receive regulatory approval for many reasons, including the following:

This lengthy approval process as well as the unpredictability of future clinical trial results may result in our failing to obtain regulatory approval to market mavacamten, danicamtiv or any other product candidate we may develop, which would significantly harm our business, results of operations and prospects.

In addition, even if we were to obtain approval, regulatory authorities may approve any of our product candidates for fewer or more limited indications than we request, may not approve the price we intend to charge for our products, may grant approval contingent on the performance of costly post-marketing clinical trials, or may approve a product candidate with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that product candidate. Any of the foregoing scenarios could materially harm the commercial prospects for our product candidates.

Although the FDA provided feedback on the Phase 3 clinical trial for mavacamten, the FDA may raise questions regarding mavacamten’s safety data, which may delay or prevent the approval of mavacamten or adversely affect our ability to commercialize mavacamten on the timelines we have announced.

The size of a safety database when submitting an NDA is usually between 3,000 to 5,000 patients. When we sought feedback on EXPLORER-HCM, our Phase 3 clinical trial for mavacamten, we estimated that at the time of submitting our NDA, our safety database would have 250 patient-years of exposure, as we are treating an orphan disease. When we submit our NDA, we anticipate that we will have approximately 200 patient-years in the safety database and at the time of submission of the 120-day safety update, it will have increased to 300-350 patient-years. While we plan to conduct a prospective registry study to demonstrate our commitment to post-approval product characterization, and the FDA has accepted a lesser number of patients for a safety database in the past, the FDA may request additional clinical data, which may delay or prevent the approval and commercialization of mavacamten and could have a negative impact on our business.

Even if we complete the necessary preclinical studies and clinical trials, we cannot predict when or if we will obtain regulatory approval to commercialize a product candidate or the approval may be for a more limited indication than we expect.

We cannot commercialize a product until the appropriate regulatory authorities have reviewed and approved the product candidate. Even if our product candidates demonstrate safety and efficacy in clinical trials, the regulatory agencies may not complete their review processes in a timely manner, or we may not be able to obtain regulatory approval. Additional delays may result if an FDA Advisory Committee or other regulatory authority recommends non-approval or restrictions on approval. In addition, we may experience delays or rejections based upon additional government regulation from future legislation or administrative action, or changes in regulatory agency policy during the period of product development, clinical trials and the review process. Regulatory agencies also may approve a treatment candidate for fewer or more limited indications than requested or may grant approval subject to the performance of post-marketing studies. In addition, regulatory agencies may not approve the labeling claims that are necessary or desirable for the successful commercialization of our treatment candidates. If we are unable to obtain regulatory approval for our product candidates for use in the treatment of cardiomyopathies, our business may suffer.

Failure to obtain marketing approval in international jurisdictions would prevent our products from being marketed in such jurisdictions.

In order to market and sell our products in the European Union and many other jurisdictions, we or any third-party collaborators must obtain separate marketing approvals and comply with numerous and varying regulatory requirements. The approval procedure varies among countries and can involve additional testing. The time required to obtain approval may differ substantially from that required to obtain FDA approval. The regulatory approval process outside the United States generally includes all of the risks associated with obtaining FDA approval. In addition, in many countries outside the United States, it is required that the product be approved for reimbursement before the product can be approved for sale in that country. We or these third parties may not obtain approvals from regulatory authorities outside the United States on a timely basis, if at all. Approval by the FDA does not ensure approval by regulatory authorities in other countries or jurisdictions, and approval by one regulatory authority outside the United States does not ensure approval by regulatory authorities in other countries or jurisdictions or by the FDA. However, the failure to obtain approval in one jurisdiction may negatively impact our ability to obtain approval in other jurisdictions. We may not be able to

file for marketing approvals, and even if we do, we may not obtain necessary approvals to commercialize our medicines in any market.

Even if we receive regulatory approval for any of our product candidates, we will be subject to ongoing obligations and continued regulatory review, which may result in significant additional expense. Additionally, our product candidates, if approved, could be subject to labeling and other restrictions and market withdrawal and we may be subject to penalties if we fail to comply with regulatory requirements or experience unanticipated problems with our products.

Any product candidate for which we obtain marketing approval, along with the manufacturing processes, post-approval clinical data, labeling, advertising and promotional activities for such product, will be subject to extensive and ongoing regulatory requirements and review by the FDA and other regulatory authorities. These requirements include submissions of safety and other post-marketing information and reports, registration and listing requirements, current Good Manufacturing Practice (cGMP) requirements relating to quality control, quality assurance and corresponding maintenance of records and documents, and requirements regarding the distribution of samples to physicians and recordkeeping. For example, the holder of an approved NDA is obligated to monitor and report adverse events and any failure of a product to meet the specifications in the NDA. The holder of an approved NDA must also submit new or supplemental applications and obtain FDA approval for certain changes to the approved product, product labeling or manufacturing process.

In addition, product manufacturers and their facilities are subject to payment of user fees and continual review and periodic inspections by the FDA and other regulatory authorities for compliance with cGMP and adherence to commitments made in the NDA and other marketing authorizations.

Even if marketing approval of a product candidate is granted, the approval may be subject to limitations on the indicated uses for which the product may be marketed or to the conditions of approval or contain requirements for costly post-marketing testing and surveillance to monitor the safety or efficacy of the medicine.

The FDA closely regulates the post-approval marketing and promotion of medicines to ensure that they are marketed only for the approved indications and in accordance with the provisions of the approved labeling. The FDA imposes stringent restrictions on manufacturers’ communications regarding off-label use and if we do not market our medicines for their approved indications, we may be subject to enforcement action for off-label marketing.

In addition, later discovery of previously unknown problems with our medicines, manufacturers or manufacturing processes, or failure to comply with regulatory requirements, may result in various negative consequences, including:

The FDA’s policies may change, and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our product candidates. If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may lose any marketing approval that we may have obtained, which would adversely affect our business, prospects and ability to achieve or sustain profitability.

Any government investigation of alleged violations of law could require us to expend significant time and resources in response and could generate negative publicity. The occurrence of any event or penalty described above may inhibit our ability to commercialize our product candidates and generate revenues.

We may seek one or more special designations from regulatory authorities to expedite the review and approval process for our product candidates, including Breakthrough Therapy Designation or Fast Track Designation. These designations may not lead to a faster development or regulatory review or approval process, and it does not increase the likelihood that our product candidates will receive marketing approval.

A breakthrough therapy is defined as a product that is intended, alone or in combination with one or more other products, to treat a serious or life-threatening disease or condition, and preliminary clinical evidence indicates that the product may demonstrate substantial improvement over existing therapies on one or more clinically important endpoints, such as substantial treatment effects observed early in clinical development. For products that have been designated as breakthrough therapies, interaction and communication between the FDA and the sponsor of the trial can help to identify the most efficient path for clinical development while minimizing the number of patients placed in ineffective control regimens. Products designated as breakthrough therapies by the FDA can also be eligible for accelerated approval. If a product is intended for the treatment of a serious or life-threatening condition and the product demonstrates the potential to address unmet medical needs for this condition, the product sponsor may apply for Fast Track Designation.

The FDA has broad discretion whether or not to grant these designations, so even if we believe a particular product candidate is eligible for a particular designation, we cannot assure you that the FDA would decide to grant it. Accordingly, even if we believe one of our product candidates meets the criteria for a designation, the FDA may disagree and instead determine not to make such designation. In any event, the receipt of a particular designation for a product candidate may not result in a faster development process, review or approval compared to products considered for approval under conventional FDA procedures and does not assure ultimate approval by the FDA. In addition, even if one or more of our product candidates qualify as breakthrough therapies, the FDA may later decide that the products no longer meet the conditions for qualification and rescind the breakthrough designation. Further, the FDA may withdraw Fast Track Designation if it believes that the designation is no longer supported by data from a clinical development program.

If we elect to pursue Breakthrough Therapy Designation or Fast Track Designation, any inability to secure or maintain the applicable designation would have an adverse impact on our development timelines and our ability to obtain approval for and commercialize our product candidates.

Risks Related to Our Limited Operating History, Financial Condition and Capital Requirements

Our limited operating history may make it difficult for you to evaluate the success of our business to date and to assess our future viability.

We are an early-stage company. We were incorporated and commenced operations in June 2012. Our operations to date have been limited to organizing and staffing our company, business planning, raising capital, developing our technology, creating and expanding on our precision medicine platform, identifying potential product candidates, undertaking preclinical studies for our programs, ~~conducting Phase 1~~completing our ongoing clinical trials for our most advanced product candidate, mavacamten, ~~(formerly known as MYK-461) and commencing and conducting Phase 2~~planning further clinical development of mavacamten and ~~Phase 1~~completing our ongoing clinical development of our second product candidate, ~~MYK-491.~~danicamtiv, and beginning clinical development of our third product candidate, MYK-224. We have not yet demonstrated our ability to successfully complete the clinical development of a product candidate, including the completion of any clinical trials designed to ~~show~~support the ~~efficacy~~registration of a product candidate, obtain marketing approvals, manufacture a commercial scale medicine, or arrange for a third party to do so on our behalf, or conduct sales and marketing activities necessary for successful commercialization. Typically, it takes many years to develop a new medicine from the time it is discovered to when it is available for treating patients. Consequently, any predictions you make about our future success or viability may not be as accurate as they could be if we had a longer operating history.

In addition, as a new business, we may encounter unforeseen expenses, difficulties, complications, delays and other known and unknown factors. We will need to transition from a company with a research and development focus to a company capable of supporting larger scale clinical development and commercial activities. If we are not successful in such a transition, our business, results and financial condition will be harmed.

We have a history of significant losses and anticipate that we will continue to incur losses for the near future and may not achieve or sustain profitability and, as a result, you may lose all or part of your investment.

Our initial product candidates, mavacamten, danicamtiv and ~~MYK-491,~~MYK-224, are in ~~the early~~various stages of clinical testing and we must successfully complete our ongoing clinical trials of mavacamten and conduct significant additional clinical trials for danicamtiv and MYK-224 before we can seek the regulatory approvals necessary to begin commercial sales of these or any other product candidates we may develop. We have incurred operating losses in each year since our inception due to costs incurred in connection with our research and development activities and selling, general and administrative costs associated with our operations. Our net loss for the ~~three and nine months~~quarter ended ~~September 30, 2017~~March 31, 2020 was ~~$14.2~~$69.9 million and ~~$38.6 million, respectively. As~~as of ~~September 30, 2017,~~March 31, 2020, we had an accumulated deficit of ~~$116.4~~$548.6 million. We expect to incur increasing losses for several years as we continue our research activities and conduct development of, and seek regulatory approvals for, our initial product candidates, and commercialize any approved drugs. If our product candidates fail in clinical trials or do not gain regulatory approval, or if our product candidates do not achieve market acceptance, we will not be profitable. If we fail to become and remain profitable, or if we are unable to fund our continuing losses, you could lose all or part of your investment.

We have never generated any revenue from product sales and may never be profitable.

Our ability to generate revenue and achieve profitability depends on our ability, alone or with strategic collaborators, to successfully complete the development of, and obtain the regulatory approvals necessary to commercialize, our product candidates. We do not anticipate generating revenues from product sales ~~for~~in the ~~foreseeable~~near future, if ever. Our ability to generate future revenue from product sales depends heavily on our success in:

Even if one or more of the product candidates that we are developing is approved for commercial sale, we anticipate incurring significant costs associated with commercializing any approved product candidate. Our expenses could increase beyond our expectations if we are required by the U.S. Food and Drug Administration (~~the “FDA”)~~(FDA), the European Medicines Agency ~~(the “EMA”)~~(EMA) or other regulatory agencies, domestic or foreign, to perform clinical trials and other studies in addition to those that we currently anticipate. Even if we are able to generate revenues from the sale of any approved products, we may not become profitable and may need to obtain additional funding to continue operations.

We will need to raise additional funding, which may not be available on acceptable terms, or at all. Failure to obtain this necessary capital when needed may force us to delay, limit or terminate our product development efforts or other operations.

We are currently advancing mavacamten, danicamtiv and ~~MYK-491,~~MYK-224, our initial product candidates, through clinical development, and conducting preclinical discovery and development activities in our other programs. Drug development is expensive, and we expect our research and development expenses to increase substantially in connection with our ongoing activities, particularly as we continue to advance our product candidates in clinical ~~trials.~~trials and identify additional product candidates from our pipeline for clinical development.

As of ~~September 30, 2017,~~March 31, 2020, our cash, ~~and~~ cash equivalents ~~were $227.2~~and investments (short-term and long-term) totaled $360.1 million. We intend to use our cash, ~~and~~ cash equivalents and investments to fund the advancement of our mavacamten clinical development program, including our ongoing ~~PIONEER-HCM~~ Phase ~~2 study~~3 clinical trial in symptomatic ~~oHCM~~obstructive HCM patients, and our planned additional clinical trials of mavacamten ~~the progression~~and danicamtiv, our ongoing Phase 1 trial of ~~MYK-491 through clinical proof-of-concept,~~MYK-224, our ongoing preclinical, discovery and research programs and the expansion of our platform, as well as for working capital and general corporate purposes. However, our operating plan may change as a result of many factors currently unknown to us, including the effects of the COVID-19 pandemic on our research and development activities, and we may need to seek additional funds sooner than planned, through public or private equity or debt financings, government or other third-party funding, marketing and distribution arrangements and other collaborations, strategic and licensing arrangements or a combination of these approaches. In any event, we will require additional capital to obtain regulatory approval for, and to commercialize, mavacamten ~~MYK-491~~, danicamtiv, MYK-224 or any other product candidates we may identify and develop. Even if we believe we have sufficient funds for our current or future operating plans, we may seek additional capital if market conditions are favorable or if we have specific strategic considerations.

Our funding requirements and the timing of our need for additional capital are subject to change based on a number of factors, including:

Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our ability to develop and commercialize our product candidates. In addition, we cannot guarantee that future financing will be available in sufficient amounts or on terms acceptable to us, if at all. Moreover, the terms of any financing may adversely affect the holdings or the rights of our stockholders and the issuance of additional securities, whether equity or debt, by us, or the possibility of such issuance, may cause the market price of our shares to decline. The sale of additional equity or convertible securities would dilute all of our stockholders. The incurrence of indebtedness would result in increased fixed payment obligations and we may be required to agree to certain restrictive covenants, such as limitations on our ability to incur additional debt, limitations on our ability to acquire, sell or license intellectual property rights and other operating restrictions that could adversely impact our ability to conduct our business. We could also be required to seek funds through arrangements with collaborative partners or otherwise at a different stage than otherwise would be desirable and we may be required to relinquish rights to some of our technologies or product candidates or otherwise agree to terms unfavorable to us, any of which may have a material adverse effect on our business, operating results and prospects.

If we are unable to obtain funding on a timely basis, we may be required to significantly curtail, delay or discontinue one or more of our research or development programs or the commercialization of any product candidates or be unable to expand our operations or otherwise capitalize on our business opportunities, as desired, which could materially and adversely affect our business, financial condition and results of operations.

Our reported financial results may be adversely affected by changes in accounting principles generally accepted in the ~~U.S.~~United States.

We prepare our financial statements in conformity with accounting principles generally accepted in the ~~U.S.~~United States. These accounting principles are subject to interpretation by the Financial Accounting Standards Board ~~(“FASB”)~~ and the Securities and Exchange ~~Commission.~~Commission (SEC). A change in these policies or interpretations could have a significant effect on our reported financial results, may retroactively affect previously reported results, could cause unexpected financial reporting fluctuations, and may require us to make costly changes to our operational processes and accounting systems. ~~In May 2014,~~

Comprehensive tax reform bills could increase the FASB issued ASU 2014-09, Revenue from Contracts with Customers, which supersedes nearly all existing U.S. GAAP revenue recognition guidance. The new standard and its amendments will be effective for our fiscal year 2018 with early adoption permitted for our fiscal year 2017. Although we are currently in the process of evaluating the impact of ASU 2014-09tax burden on our consolidated financial statements, it could change the way we account for certain of our revenue transactions. Thus, adoption of the standard could have a significant impact on our financial statements and may retroactively affect the accounting treatment of transactions completed before adoption. See “Note 2 – ~~Summary of Significant Accounting Policies” for additional discussion of the accounting changes.~~

~~Risks Related to Our Precision Medicine Platform and the Discovery and Development of Our Product Candidates~~

~~The precision medicine approach we are taking to discover and develop drugs for heritable cardiovascular diseases is novel and may never lead to marketable products.~~

We have concentrated our therapeutic product research and development efforts on the application of precision medicine to the treatment of heritable cardiovascular diseases, and our future success depends on the successful development of products based on our precision medicine platform and the continued development of this platform. We believe we are the first company to apply precision medicine to the treatment of cardiovascular disease, and neither we nor any other company has received regulatory approval to market therapeutics specifically targeting any form of heritable cardiomyopathy. The scientific discoveries that form the basis for our efforts to discover and develop product candidates are novel, and the scientific evidence to support the feasibility of developing product candidates based on these discoveries is both preliminary and limited. If we do not successfully develop and commercialize product candidates based upon our technological approach, we will not become profitable and the value of our common stock may decline.

~~Further, our focus solely on precision medicine for the development of drugs for heritable cardiomyopathies as opposed to multiple, more proven technologies for~~orphan drug development increases the risks associated with the ownership of our common stock. If we are not successful in developing any product candidates using our precision medicine platform, we may be required to change the scope and direction of our product development activities. In that case, we may not be able to identify and implement successfully an alternative product development strategy, which would materiallyprograms and adversely affect our business and financial condition.

In December 2017, the U.S. government enacted comprehensive tax legislation that includes significant changes to the taxation of business entities. These changes include, among others, (i) a permanent reduction to the corporate income tax rate, (ii) a partial limitation on the deductibility of business interest expense, (iii) a shift of the U.S. taxation of multinational corporations from a tax on worldwide income to a generally more territorial focused system (along with certain rules designed to prevent erosion of the U.S. income tax base) and (iv) a one-time tax on accumulated offshore earnings held in cash and illiquid assets, with the latter taxed at a lower rate.

Further, the recently enacted comprehensive tax legislation, among other things, reduces the orphan drug tax credit from 50% to 25% of qualifying expenditures. When and if we become profitable, this reduction in tax credits may result in an increased federal income tax burden on our orphan drug programs as it may cause us to pay federal income taxes earlier under the revised tax law than under the prior law and, despite being partially off-set by a reduction in the corporate tax rate from a top marginal rate of 35% to a flat rate of 21%, may increase our total federal tax liability attributable to such programs.

Notwithstanding the reduction in the corporate income tax rate, the overall impact of this tax reform is uncertain, and our business and financial condition could be adversely affected. In addition, it is uncertain if and ~~results of operations.~~to what extent various states will conform to this federal tax law.

We ~~depend heavily on the success of mavacamten (formerly known as MYK-461) and MYK-491, our initial product candidates. Other than mavacamten and MYK-491, all of our other programs are in discovery~~may choose not to develop a potential drug candidate, or preclinical development. Preclinical testing and clinical trials of our product candidates may not be successful. If we are unable to commercialize our product candidates or experience significant delays in doing so, our business will be materially harmed.

~~We have invested a significant portion of our efforts and financial resources in the identification of our initial product candidates, mavacamten for the treatment of hypertrophic cardiomyopathy (“~~HCM”) and MYK-491 for the treatment of dilated cardiomyopathy (“DCM”). We are currently evaluating mavacamten and MYK-491 in early-stage clinical trials, and, if these product candidates fail to demonstrate safety or efficacy in their respective target indications to the satisfaction of the FDA or other comparable regulatory authorities, we will need to identify and rely on other product candidates or target indications, or both, for clinical development. All of our other programs are still in discovery or preclinical development. Our ability to generate revenue from product sales, which we do not expect will occur for many years, if ever, will depend heavily on the successful development and eventual commercialization of mavacamten, MYK-491 or other product candidates that we may ~~identify from our precision medicine platform.~~

~~The success of mavacamten, MYK-491 and any other product candidates that we discover and develop will depend on many factors, including the following:~~

~~If we do not achieve~~terminate one or more ~~of these factors in a timely manner~~discovery programs or ~~at all, we could experience significant delays~~pre-clinical drug candidates or ~~an inability to successfully commercialize our product candidates, which would materially harm our business.~~

~~Preclinical and clinical testing is expensive and can take many years to complete, and its outcome is inherently uncertain. Failure can occur at~~At any time ~~during the preclinical development or clinical trial process. The results of preclinical studies~~ and early clinical trials of our product candidates may not be predictive of the results of later-stage clinical trials. For example, although our preclinical observations and data generated to date from our Phase 1 clinical trials of mavacamten support our hypothesis that mavacamten has the potential to reduce cardiac muscle contractility and our belief that such data have demonstrated clinical proof of mechanism in both HCM patients and healthy volunteers, we have not completed clinical trials of mavacamten in larger populations. In addition, our precision medicine platform is based on a translational medicine approach. Translational medicine, or the application of basic scientific findings to develop therapeutics that promote human health, is subject to a number of inherent risks. In particular, scientific hypotheses formed from preclinical or early clinical observations may prove to be incorrect, and the data generated in animal models or observed in limited patient populations may be of limited value, and may not be applicable in clinical trials conducted under the controlled conditions required by applicable regulatory requirements and our protocols. For example, although mavacamten has been observed to reduce cardiac contractility as measured by certain established biomarkers in our first Phase 1 clinical trial in healthy volunteers, the predictive value of these biomarkers in HCM patients may prove to be less than anticipated in subsequent, larger clinical trials. The initial clinical data from our Phase 1 clinical trials of mavacamten are preliminary in nature, based on limited doses and a small sample size, and the clinical development of mavacamten is not complete. Early positive data may not be repeated or observed in ongoing or future trials involving our product candidates. Product candidates in later stages of clinical trials may fail to show the desired safety and efficacy traits despite having progressed through preclinical studies and initial clinical trials. There is a high failure rate for drugs and biologics proceeding through clinical trials, particularly in the field of cardiovascular medicine. A number of companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in clinical development even after achieving promising results in earlier studies, and any ~~such setbacks in our clinical development could have a material adverse effect on our business and operating results.~~

~~We may encounter substantial delays in our clinical trials or~~reason, we may ~~fail to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities.~~

Before obtaining marketing approval from regulatory authorities for the sale of our product candidates, we must conduct extensive clinical trials to demonstrate the safety and efficacy of the product candidates in humans. Clinical testing is expensive, time-consuming and uncertain as to outcome. We cannot guaranteedetermine that any clinical trials will be conducted as planned or completed on schedule, if at all. A failure of one or more clinical trials can occur at any stage of testing. We may experience delays in our ongoing clinical trials and we do not know whether planned clinical trials will begin on time, need to be redesigned, enroll patients on time or be completed on schedule, if at all. Additionally, although we believe that our precision medicine approach should eliminate the need for mavacamten to undergo the large outcomes-based studies that are often required for cardiovascular drugs as a condition to regulatory approval by the FDA or other regulatory authorities, regulatory authorities may nevertheless require us to conduct additional trials or generate additional data, including potential trials studying the interaction of our product candidates with other therapeutics commonly administered in the patient populations we are seeking to treat, which would increase the time and cost of our clinical development process. Furthermore, we will need to conduct larger clinical trials, and the FDA may subsequently require us to evaluate a larger number of patients than we presently anticipate, or to assess other endpoints besides those presently contemplated, in order to support regulatory approval.

We could encounter delays if a clinical trial is suspended or terminated by us, by the IRBs of the institutions in which such trials are being conducted, or suspension or termination is recommended by the Data Safety Monitoring Board (“DSMB”) for such trial or by the FDA or other regulatory authorities. Such authorities may impose such a suspension or termination due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a drug, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial.

~~Any inability~~discovery programs or preclinical drug candidates or programs does not have sufficient potential to ~~successfully complete preclinical and clinical development could result in additional costs to us~~warrant the allocation of resources toward such program or impair our ability to generate revenues from product sales, regulatory and commercialization milestones and royalties. In addition, if we make manufacturing or formulation changes to our product candidates,drug candidate. Accordingly, we may ~~need~~choose not to conduct additional studies to bridge our modified product candidates to earlier versions. Clinical trial delays could also shorten any periods during which we may have the exclusive right to commercialize our product candidates or allow our competitors to bring products to market before we do, which could impair our ability to successfully commercialize our product candidates and may harm our business and results of operations. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates.

~~If the results of our clinical trials are inconclusive or if there are safety concerns or adverse events associated with our product candidates, we may:~~

~~We may find it difficult to enroll patients in our clinical trials, which could delay or prevent clinical trials of our product candidates.~~

Identifying and qualifying patients to participate in clinical trials of our product candidates is critical to our success. The timing to commence and complete our clinical trials depends on the speed at which we can recruit patients to participate in testing our product candidates. If patients are unwilling to participate in our clinical trials because of a lack of familiarity with our approach to the treatment of cardiovascular diseases, negative publicity from adverse events in biotechnology or the fields of precision medicine or cardiovascular disease or for other reasons, including competitive clinical trials for similar patient populations, our timelines for recruiting patients, conducting clinical trials and obtaining regulatory approval of potential products may be delayed. These delays could result in increased costs, delays in advancing our product development, delays in testing the effectiveness of our technology or termination of our clinical trials altogether.

In particular, each of the conditions in which we plan to evaluate our current product candidates is a rare genetic disorder with limited patient pools from which to draw for clinical trials. To date, the HCM and DCM patient populations have not been extensively evaluated in clinical trials. As a result, enrollment in our ongoing and planned clinical trials is difficult to predict and may take longer or cost more than we anticipate.

~~We may not be successful in our efforts to identify or discover potential product candidates.~~

~~The success of our business depends primarily upon our ability to identify,~~ develop and commercialize therapeutics for the treatment of genetic cardiovascular diseases based on our precision medicine approach. A key element of our strategy is to use our precision medicine platform to identify and study compounds that can be used to correct or offset the abnormal contraction caused by HCM and DCM. Our research programs may initially show promise in identifying potential product candidates, yet fail to yield product candidates for clinical development for a number of reasons, including:

We may not be able to successfully use the Sarcomeric Human Cardiomyopathy Registry, or SHaRe, to identify or recruit patients for our clinical trials or to develop targeted precision therapeutics for the treatment of heritable cardiomyopathies.

We rely, and expect to continue to rely, on genetic and clinical data gathered through SHaRe to provide us with insight into risk profiles and disease progression in heritable cardiomyopathies. Although the body of information in SHaRe is growing, we may face challenges collecting additional data through SHaRe in the future for a variety of reasons, including:

Additionally, the predictive value of the information generated through SHaRe to date may be limited. Although we expect to use these data to define and identify patient subgroups most likely to respond to our product candidates, our initial hypotheses regarding these data may prove to be incorrect, or our patient selection strategies based on our analysis of these data may fail to yield suitable patients for evaluation in our clinical trials or suitable indications and product candidates for clinical development.

Adverse events or other unintended side effects or safety signals caused by our product candidates could cause us, IRBs or ethics committees, clinical trial sites or regulatory authorities to interrupt, delay or halt clinical trials and could result in the denial of regulatory approval. For example, through additional studies, we may determine that although mavacamten has been shown to be specific to striated muscle, which includes both skeletal and cardiac muscle, and selective for cardiac muscle, it may target myosin in skeletal muscle, which could result in unintended adverse effects. We have observed a number of adverse events in our clinical trials of mavacamten. In particular, we have observed at least one serious adverse event to date that occurred in the highest dose cohort of our single ascending dose Phase 1 clinical trial of mavacamten in HCM patients, which was described as a transient episode of hypotension and asystole, due to a vasovagal reaction, or low blood pressure and a temporary loss of heartbeat due to a nervous system reflex. Results of our ongoing and planned trials could reveal a high and unacceptable severity and prevalence of these or other adverse events in subjects treated with our product candidates. Additionally, if the adverse events we have observed are deemed to be unacceptable or other unacceptable side effects or safety signals are observed in any ongoing or subsequent preclinical studies or clinical trials of our product candidates, our trials could be suspended or terminated and the FDA or comparable foreign regulatory authorities could order us to cease further development of or deny approval of our product candidates for any or all targeted indications. Any adverse effects encountered in our preclinical studies or clinical trials, whether or not drug-related, could affect patient recruitment or the ability of enrolled patients to complete the trial or result in potential product liability claims. Additionally,

adverse effects may represent safety signals that could influence the benefit-risk assessment for further development or commercialization of a product candidate and may warrant further clinical or nonclinical investigation, consultation with health authorities, changes to product labeling or guidelines for its safe use, or other scientific or regulatory actions. Any of these occurrences may harm our business, financial condition and prospects significantly.

~~Our product candidates could fail to receive regulatory approval for many reasons, including the following:~~

This lengthy approval process as well as the unpredictability of future clinical trial results may result in our failing to obtain regulatory approval to market mavacamten, MYK-491 or any other product candidate we may develop, which would significantly harm our business, results of operations and prospects.

~~Even if we complete the necessary preclinical studies and clinical trials, we cannot predict when or if we will obtain regulatory approval to commercialize a product~~drug candidate or ~~the approval may be for a more limited indication than we expect.~~

We cannot commercialize a product until the appropriate regulatory authorities have reviewed and approved the product candidate. Even if our product candidates demonstrate safety and efficacy in clinical trials, the regulatory agencies may not complete their review processes in a timely manner,elect to suspend, deprioritize or we may not be able to obtain regulatory approval. Additional delays may result if an FDA Advisory Committee or other regulatory authority recommends non-approval or restrictions on approval. In addition, we may experience delays or rejections based upon additional government regulation from future legislation or administrative action, or changes in regulatory agency policy during the period of product development, clinical trials and the review process. Regulatory agencies also may approve a treatment candidate for fewer or more limited indications than requested or may grant approval subject to the performance of post-marketing studies. In addition, regulatory agencies may not approve the labeling claims that are necessary or desirable for the successful commercialization of our treatment candidates. If we are unable to obtain regulatory approval for our product candidates for use in the treatment of heritable cardiomyopathies, our business may suffer.

~~Failure to obtain marketing approval in international jurisdictions would prevent our products from being marketed in such jurisdictions.~~

In order to market and sell our products in the European Union and many other jurisdictions, we or our third-party collaborators must obtain separate marketing approvals and comply with numerous and varying regulatory requirements. The approval procedure varies among countries and can involve additional testing. The time required to obtain approval may differ substantially from that required to obtain FDA approval. The regulatory approval process outside the United States generally includes all of the risks associated with obtaining FDA approval. In addition, in many countries outside the United States, it is required that the product be approved for reimbursement before the product can be approved for sale in that country. We or these third parties may not obtain approvals from regulatory authorities outside the United States on a timely basis, if at all. Approval by the FDA does not ensure approval by regulatory authorities in other countries or jurisdictions, and approval by one regulatory authority outside the United States does not ensure approval by regulatory authorities in other countries or jurisdictions or by the FDA. However, the failure to obtain approval in one jurisdiction may negatively impact our ability to obtain approval in other jurisdictions. We may not be able to file for marketing approvals, and even if we do, we may not obtain necessary approvals to commercialize our medicines in any market.

Any product candidate for which we obtain marketing approval, along with the manufacturing processes, post-approval clinical data, labeling, advertising and promotional activities for such product, will be subject to extensive and ongoing regulatory requirements and review by the FDA and other regulatory authorities. These requirements include submissions of safety and other post-marketing information and reports, registration and listing requirements, current Good Manufacturing Practice (“cGMP”) requirements relating to quality control, quality assurance and corresponding maintenance of records and documents, and requirements regarding the distribution of samples to physicians and recordkeeping. For example, the holder of an approved NDA is obligated to monitor and report adverse events and any failure of a product to meet the specifications in the NDA. The holder of an approved NDA must also submit new or supplemental applications and obtain FDA approval for certain changes to the approved product, product labeling or manufacturing process.

Even if marketing approval of a product candidate is granted, the approval may be subject to limitations on the indicated uses for which the product may be marketed or to the conditions of approval, or contain requirements for costly post-marketing testing and surveillance to monitor the safety or efficacy of the medicine.

The FDA’s policies may change and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our product candidates. If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may lose any marketing approval that we may have obtained, which would adversely affect our business, prospects and ability to achieve or sustain profitability.

We may seek one or more special designations from regulatory authorities for our product candidates, including Breakthrough Therapy Designation, Fast Track Designation or Orphan Drug Designation. These designations may not lead to a faster development or regulatory review or approval process, and it does not increase the likelihood that our product candidates will receive marketing approval.

~~We may seek one or more special designations from regulatory authorities for our product candidates, including Breakthrough Therapy Designation, Fast Track Designation or Orphan Drug Designation.~~

~~process, review or approval compared to products considered for approval under conventional FDA procedures and does not assure ultimate approval by the FDA. In addition, even if~~terminate one or more of our ~~product~~discovery programs or preclinical drug candidates qualify as breakthrough therapies, the FDA may later decide that the products no longer meet the conditions for qualification and rescind the breakthrough designation. Further, the FDA may withdraw Fast Track Designation if it believes that the designation is no longer supported by data fromor programs. If we suspend, deprioritize or terminate a ~~clinical development program.~~

~~Regulatory authorities~~program or drug candidate in some jurisdictions, including the United States and Europe, may designate drugs for relatively small patient populations as orphan drugs. Under the Orphan Drug Act, the FDA may designate a drug as an orphan drug if it is a drug intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals annually in the United States, or a patient population greater than 200,000 in the United States where there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the United States. In the United States, Orphan Drug Designation entitles a party to incentives such as tax advantages and user-fee waivers. In April 2016, the FDA granted Orphan Drug Designation for mavacamten for use in the treatment of symptomatic obstructive HCM.

In addition, if a product that has Orphan Drug Designation subsequently receives the first approval for the disease for which it has such designation, the product is entitled to orphan drug exclusivity, which in the United States means that the FDA may not approve any other applications to market the same drug for the same indication for seven years, except in limited circumstances.~~The exclusivity granted under any Orphan Drug Designations that~~ we have ~~received or may receive may~~invested significant resources, we will have expended resources on a program that will not ~~effectively protect the product candidate from competition.~~ Although we have received Orphan Drug Designation from the FDA for mavacamten for use in the treatment of symptomatic obstructive HCM, we may not be the first to obtain marketing approval of this drug for the orphan-designated indication due to the uncertainties associated with developing pharmaceutical products. In addition, exclusive marketing rights in the United States may be limited if we seek approval for an indication broader than the orphan-designated indication or may be lost if the FDA later determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantities of the product to meet the needs of patients with the rare disease or condition. Further, even if we obtain orphan drug exclusivity, that exclusivity may not effectively protect the product from competition ~~because different drugs~~ ~~with different active moietiescan be approved for the same condition. Even after an orphan drug is approved, the FDA can subsequently approve another drug~~ ~~with the same active moiety~~ ~~for the same condition if the FDA concludes that the later drug is clinically superior, in that it is shown to be safer, more effective or makes~~provide a ~~major contribution to patient care.~~ ~~Orphan Drug Designation neither shortens the development time or regulatory review time of a drug nor gives the drug any advantage in the regulatory review or approval process.Any inability to secure or maintain Orphan Drug Designation or the exclusivity benefits of this designation would have an adverse impact~~full return on our ~~ability~~investment and may have missed the opportunity to ~~develop and commercialize our product~~have allocated those resources to potentially more productive uses, including existing or future programs or drug candidates.

~~We are~~From the inception of our collaboration arrangement with Sanofi in August of 2014 and through December 31, 2018 we were substantially dependent upon ~~our collaboration agreement with~~ Sanofi for the development and eventual commercialization of mavacamten, ~~MYK-491~~danicamtiv, and ~~any product candidates from our HCM-2 program. If this collaboration is unsuccessful or is terminated,~~MYK-224. As a result of the termination of the arrangement, we may be unable to commercialize certain product ~~candidates and we will not receive additional funding from this relationship~~.candidates.

We ~~depend~~have previously depended upon our license and collaboration agreement with Aventis Inc., a wholly-owned subsidiary of Sanofi S.A. (Sanofi), which we refer to as the Collaboration Agreement, for financial and scientific resources related to the clinical development and commercialization of product candidates under our mavacamten ~~MYK-491~~, MYK-224, danicamtiv and HCM-2 ~~programs. While Sanofi has obligations to fund various research~~programs and ~~development activities under~~for the ~~collaboration and with respect to the commercialization~~manufacturing of product candidates in selected territories under certain programs under the Collaboration Agreement, our ability to receive funding from this relationship will depend upon the ability and willingness of Sanofi to successfully meet its responsibilities under our Collaboration Agreement and continue the collaboration. We may not receive some or all of the financial and scientific resources that we currently expect to receive under our Collaboration Agreement.

~~Our ability to generate additional funding from our Collaboration Agreement may be impaired by several factors including:~~

~~Specifically, with respect to termination, the initial term of the research program under our Collaboration Agreement with Sanofi is set to end on December 31, 2018. At any time after~~danicamtiv. On December 31, 2018, Sanofi ~~may, upon prior written notice~~notified us of their intent to ~~us,~~ terminate the ~~Collaboration Agreement~~collaboration and as a result, reimbursement for ~~convenience~~our research and development collaboration on mavacamten and MYK-224 ended in ~~its entirety or on a region-by-region or program-by-program basis~~the first half of 2019. In addition, Sanofi did not elect to continue with the danicamtiv and HCM-2 programs, and the collaboration with respect to ~~selected regions or programs. The Collaboration Agreement is also subject to~~such programs was deemed terminated as of December 31, 2018. As a result of the termination, ~~by either party upon a material breach by the other party, subject to a notice and cure period, or upon a bankruptcy, insolvency or similar event affecting the other party.~~

~~If our Collaboration Agreement with Sanofi is terminated, then, depending on the event:~~

~~Any of these events would~~ have a material adverse effect on our results of operations and financial condition.

We may enter into collaborations that place the development and commercialization of our product candidates outside our control, require us to relinquish important rights or may otherwise be on terms unfavorable to us, and if our collaborations are not successful, our product candidates may not reach their full market potential.

Our drug development programs and the potential commercialization of our drug candidates will require substantial additional cash to fund expenses. For some of our drug candidates, we may decide to collaborate with additional pharmaceutical and biotechnology companies for the development and potential commercialization of those drug candidates. We face significant competition in seeking appropriate collaborators. Whether we reach a definitive agreement for a collaboration will depend, among other things, upon our assessment of the collaborator’s resources and expertise, the terms and conditions of the proposed collaboration and the proposed collaborator’s evaluation of a number of factors. Those factors may include the design or results of clinical trials, the likelihood of approval by the FDA or similar regulatory authorities outside the United States, the potential market for the subject drug candidate, the costs and complexities of manufacturing and delivering such drug candidate to patients, the potential of competing drugs, the existence of uncertainty with respect to our ownership of technology, which can exist if there is a challenge to such ownership without regard to the merits of the challenge and industry and market conditions generally. The collaborator may also consider alternative drug candidates or technologies for similar indications that may be available to collaborate on and whether such a collaboration could be more attractive than the one with us for our drug candidate. The terms of any additional collaborations or other arrangements that we may establish may not be favorable to us.

Collaborations are complex and time-consuming to negotiate and document. In addition, there have been a significant number of recent business combinations among large pharmaceutical companies that have resulted in a reduced number of potential future collaborators.

We may not be able to negotiate additional collaborations on a timely basis, on acceptable terms or at all. If we are unable to do so, we may have to curtail the development of the drug candidate for which we are seeking to collaborate, reduce or delay its development program or one or more of our other development programs, delay its potential commercialization or reduce the scope of any sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to increase our expenditures to fund development or commercialization activities on our own, we may need to obtain additional capital, which may not be available to us on acceptable terms or at all. If we do not have sufficient funds, we may not be able to further develop our drug candidates or bring them to market and generate drug revenue. The success of our collaboration arrangements will depend heavily on the efforts and activities of our collaborators. Collaborators generally have significant discretion in determining the efforts and resources that they will apply to these collaborations. Disagreements between parties to a collaboration arrangement regarding clinical development and commercialization matters can lead to delays in the development process or commercializing the applicable drug candidate and, in some cases, termination of the collaboration arrangement. These disagreements can be difficult to resolve if neither of the parties has final decision-making authority. Collaborations with pharmaceutical or biotechnology companies and other third parties often are terminated or allowed to expire by the other party.

We expect to rely on third parties to conduct some or all aspects of our clinical trials, protocol development and research and ~~preclinical and clinical testing,~~development activities, and these third parties may not perform satisfactorily.

We ~~do not expect~~currently rely on third parties to ~~independently~~ conduct ~~all aspects of~~ our ~~protocol development, research and preclinical and~~ clinical ~~testing. We currently rely,~~trials and expect to continue to rely on third parties with respect to ~~these items.~~some or all aspects of our clinical trials, protocol development and research and development activities.

Any of these third parties may terminate their engagements with us at any time. If we need to enter into alternative arrangements, it could delay our product development activities. Our reliance on these third parties for research and development activities will reduce our control over these activities but will not relieve us of our responsibility to ensure compliance with all required regulations and study protocols. For product candidates that we develop and commercialize on our own, we will remain responsible for ensuring that each of our preclinical studies and clinical trials are conducted in accordance with the study plan and protocols. We and our third-party contractors and CROs are required to comply with GCP regulations, which are regulations and guidelines enforced by the FDA, the Competent Authorities of the Member States of the European Economic Area (“~~EEA”)~~(EEA), and comparable foreign regulatory authorities for all products in clinical development. Regulatory authorities enforce these GCP requirements through periodic inspections of trial sponsors, principal investigators and trial sites. If we or any of our third-party contractors or CROs fail to comply with applicable GCP requirements, the clinical data generated in our clinical trials may be deemed unreliable and the FDA, EMA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. We cannot assure that upon inspection by a given regulatory authority, such regulatory authority will determine that any of our clinical trials complies with GCP regulations. In addition, our clinical trials must be conducted with product produced under cGMP regulations. Our failure to comply with these regulations may require us to repeat clinical trials, which would delay the regulatory approval process.

If these third parties do not successfully carry out their contractual duties, meet expected deadlines or conduct our studies in accordance with regulatory requirements or our stated study plans and protocols, we will be delayed in completing, or may not be able to complete, the preclinical and clinical studies required to support future ~~IND~~Investigational New Drug Application (IND) submissions and approval of our product candidates. Any of these events could lead to clinical ~~study~~trial delays or failure to obtain regulatory approval or impact our ability to successfully commercialize future products. Some of these events could be the basis for FDA action, including injunction, request for voluntary recall, seizure or total or partial suspension of production.

We contract with third parties for the manufacture of our product candidates for preclinical and clinical testing and expect to continue to do so for commercialization. This reliance on third parties increases the risk that we will not have sufficient quantities of our product candidates or medicines or that such supply will not be available to us at an acceptable cost, which could delay, prevent or impair our development or commercialization efforts.

We do not have, nor do we plan to acquire, any manufacturing facilities. We currently rely, and expect to continue to rely, on third-party manufacturers for the manufacture of our product candidates for preclinical and clinical testing and for the commercial supply of any of these product candidates for which we ~~or our collaborators~~may obtain marketing approval. To date, we have obtained materials for mavacamten for our ~~Phase 1~~ clinical trials ~~and our ongoing PIONEER-HCM Phase 2 clinical trial~~ from third-party manufacturers, and we intend to rely on third-party manufacturers for our ~~ongoing~~planned Phase 2 and ~~planned~~Phase 3 clinical development activities for mavacamten and ~~MYK-491~~for our Phase 2 and any subsequent clinical trials of danicamtiv. ~~We do not~~Due to the Sanofi Collaboration Agreement termination on December 31, 2018, we no longer rely on Sanofi for our danicamtiv supplies and have ~~a long term supply agreement~~executed service agreements with ~~the~~other third-party manufacturers ~~and we purchase our required drug supply on a purchase order basis. We may be unable to establish any agreements with third-party manufacturers or to do so on acceptable terms.~~ for the manufacturing of danicamtiv.

Reliance on third-party manufacturers entails risks to which we would not be subject if we manufactured the product candidates ourselves, including:

The facilities used by our contract manufacturers to manufacture any of our future products must be evaluated by the FDA pursuant to inspections that will be conducted after we submit an NDA to the FDA. We do not control the manufacturing process of, and are completely dependent on, our contract manufacturing partners for compliance with the cGMP regulation for manufacture of both active drug substances and finished drug products. If our contract manufacturers cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or others, they will not be able to secure and/or maintain regulatory approval for their manufacturing ~~facilities.~~facilities or our marketing applications will not be approved. In addition, we have no control over the ability of our contract manufacturers to maintain adequate quality control, quality assurance and qualified personnel. If the FDA or a comparable foreign regulatory authority finds deficiencies with or does not approve these facilities for the manufacture of our product candidates or if it finds deficiencies or withdraws any such approval in the future, we may need to find alternative manufacturing facilities, which would significantly impact our ability to develop, obtain regulatory approval for or market our product candidates, if approved. Third-party manufacturers may not be able to comply with cGMP regulations or similar regulatory requirements outside the United States. Our failure, or the failure of our third-party manufacturers, to comply with applicable regulations could result in sanctions being imposed on us, including fines, injunctions, civil penalties, delays, suspension or withdrawal of approvals, license revocation, seizures or voluntary recalls of product candidates or medicines, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect supplies of our medicines and harm our business and results of operations.

Any products that we may develop may compete with our other product candidates and products and the products of third parties for access to manufacturing facilities. There are a limited number of manufacturers that operate under cGMP regulations and that might be capable of manufacturing for us.

Any performance failure on the part of our existing or future manufacturers could delay clinical development or marketing approval. We do not currently have arrangements in place for a redundant supply of bulk drug substances. If any one of our current contract manufacturers cannot perform as agreed, we may be required to replace that manufacturer. Although we believe that there are

several potential alternative manufacturers who could manufacture our product candidates, we may incur added costs and delays in identifying and qualifying any such replacement.

Our current and anticipated future dependence upon others for the manufacture of our product candidates or medicines may adversely affect our future profit margins and our ability to commercialize any medicines that receive marketing approval on a timely and competitive basis.

If we are unable to obtain and maintain patent protection for our medicines and technology, or if the scope of the patent protection obtained is not sufficiently broad, our competitors could develop and commercialize medicines and technology similar or identical to ours, and our ability to successfully commercialize our medicines and technology may be adversely affected.

Our commercial success will depend, in part, on our ability to obtain and maintain patent protection in the United States and other countries with respect to our proprietary products and technology. We seek to protect our proprietary position by filing patent applications in the United States and abroad related to our novel technologies and medicines that are important to our ~~business. To date,~~business, by pursuing the grant of patents from those applications around the world, and by taking steps to defend those patents if challenged by third parties. It is not uncommon in the pharmaceutical industry for patents covering successful drugs to be challenged for invalidity by third parties before or after the grant of such patents by a patent office (e.g., by a pre- or post-grant proceeding in a patent office or a court action). Currently we own ~~two~~five issued U.S. patents, several foreign patents and multiple pending applications worldwide that ~~cover~~relate to our proprietary technology or product candidates. We cannot be certain that we will secure any additional rights to any issued patents with claims that cover any of our proprietary technology or product candidates.

The patent prosecution process is expensive and time-consuming, and we may not be able to file and prosecute all necessary or desirable patent applications at a reasonable cost or in a timely manner. It is also possible that we will fail to identify patentable aspects of our research and development output before it is too late to obtain patent ~~protection.~~protection on or due to the public disclosures of others or ourselves. Although we enter into non-disclosure and confidentiality agreements with parties who have access to patentable aspects of our research and development output, such as our employees, corporate collaborators, outside scientific collaborators, CROs, contract manufacturers, consultants, advisors and other third parties, any of these parties may breach the agreements and disclose such output before a patent application is filed, thereby jeopardizing our ability to seek patent protection.

If we are unable to protect the confidentiality of our trade secrets, our business and competitive position would be harmed.

In addition to seeking patents for some of our technology and medicines, we also rely on trade secrets, including unpatented know-how, technology and other proprietary information, to maintain our competitive position. With respect to our proprietary ~~molecularly targeted small molecule drugs,~~scientific insights, screening assays and manufacturing processes, we consider trade secrets and know-how to be our primary intellectual property. Trade secrets and know-how can be difficult to protect. In particular, we anticipate that with respect to our precision medicine platform, these trade secrets and know-how will over time be ~~disseminated~~acquired within the industry through independent development, the publication of journal articles describing ~~the methodology,~~methodologies and insights, and the movement of personnel skilled in the art ~~from academic to industry scientific positions.~~into the pharmaceutical and biotechnology industry.

We seek to protect these trade secrets, in part, by entering into non-disclosure and confidentiality agreements with parties who have access to them, such as our employees, corporate collaborators, outside scientific collaborators, CROs, contract manufacturers, consultants, advisors and other third parties. We also enter into confidentiality and invention or patent assignment agreements with our employees and consultants. Despite these efforts, any of these parties may breach the agreements and disclose our proprietary information, including our trade secrets, and we may not be able to obtain adequate remedies for such breaches. Enforcing a claim that a party illegally disclosed or misappropriated a trade secret is difficult, expensive and time-consuming, and the outcome is unpredictable. In addition, some courts inside and outside the United States are less willing or unwilling to protect trade ~~secrets.~~secrets, and discovery processes to aid in proving trade secret misappropriation may be limited in many foreign countries. If any of our trade secrets were to be lawfully obtained or independently developed by a competitor or other third party, we ~~would~~may have no right to prevent them from using that technology or information to compete with us. If any of our trade secrets were to be disclosed to or independently developed by a competitor or other third party, our competitive position ~~would~~could be harmed.

Third-party claims of intellectual property infringement may prevent or delay our development and commercialization efforts.

Our commercial success depends in part on our avoiding infringement of the patents and proprietary rights of third parties. There is a substantial amount of litigation, both within and outside the United States, involving patent and other intellectual property rights in the biotechnology and pharmaceutical industries, including court actions for patent infringement ~~lawsuits, interferences, oppositions~~or nullification, pre- and ~~inter partes~~ ~~reexamination~~post-grant proceedings before the U.S. Patent and Trademark Office ~~or the U.S. PTO,~~(USPTO), and corresponding proceedings in foreign patent

offices. Numerous U.S. and foreign issued patents and pending patent applications, which are owned by third parties, exist in the fields in which we are pursuing development candidates. As the biotechnology and pharmaceutical industries expand and more patents are issued, the risk increases that our product candidates may be subject to claims of infringement of the patent rights of third parties.

Third parties may assert that we are employing their proprietary technology without authorization. There may be third-party patents or patent applications with claims to materials, formulations, methods of manufacture or methods for treatment related to the use or manufacture of our product candidates. Because patent applications can take many years to issue, there may be currently pending patent applications which may later result in issued patents that our product candidates may infringe. In addition, third parties may obtain patents in the future and claim that use of our technologies infringes upon these patents. If any third-party patents were held by a court of competent jurisdiction to cover the manufacturing process of any of our product candidates, any molecules formed during the manufacturing process or any final product itself, the holders of any such patents may be able to block or delay our ability to commercialize such product candidate unless we obtained a license under the applicable patents, or until such patents expire.

Similarly, if any third-party patents were held by a court of competent jurisdiction to cover aspects of our formulations, processes for manufacture or methods of use, including combination therapy, the holders of any such patents may be able to block our ability to develop and commercialize the applicable product candidate unless we obtained a license or until such patent expires. In either case, such a license may not be available on commercially reasonable terms or at all.

Parties making claims against us may also obtain injunctive or other equitable relief, which could effectively block or delay our ability to further develop and commercialize one or more of our product candidates. Defense of these claims, regardless of their merit, ~~would~~could involve substantial litigation expense and ~~would~~could be a substantial diversion of employee resources from our business. In the event of a successful claim of infringement against us, we may ~~have~~be required to ~~pay~~take a number of steps, including but not limited to, paying substantial damages, including treble damages and attorneys’ fees for willful infringement, ~~pay~~paying lost profits or royalties, ~~redesign~~redesigning our infringing products or ~~obtain~~manufacturing process, obtaining one or more licenses from third parties for activities going forward, which may be impossible or require substantial time and monetary expenditure.

Parties making claims against us may be able to sustain the costs of complex patent litigation more effectively than we can because they have substantially greater resources. In addition, any uncertainties resulting from the initiation and continuation of any litigation could have material adverse effect on our ability to raise additional funds or otherwise have a material adverse effect on our business, results of operations, financial condition and prospects.

We may be involved in lawsuits to protect or enforce our patents or the patents of our licensors, which could be expensive, time-consuming and unsuccessful.

Competitors may infringe our patents or the patents of our licensors. To counter infringement or unauthorized use, we may be required to file infringement claims, which can be expensive and time-consuming. In addition, in an infringement proceeding, a court may decide that a patent of ours or our licensors is not valid, is unenforceable and/or is not infringed, or may refuse to stop the other party from using the technology at issue ~~on the grounds~~for many reasons, including but not limited to, a determination that our patents do not cover the technology in question. Interference proceedings provoked by third parties or brought by us may be necessary to determine the priority of inventions with respect to our patents or patent applications or those of our ~~licensors.~~licensors or collaborators. An adverse result in any litigation or ~~defense proceedings~~patent office proceeding could put one or more of our patents at risk, for example, of being invalidated, deemed unenforceable or interpreted narrowly ~~and~~or could put our patent applications at risk of not issuing.

An unfavorable outcome could require us to cease using ~~the related~~a technology or to attempt to license rights to it from the prevailing party. Our business could be harmed if the prevailing party does not offer us a license on commercially reasonable terms. Our defense of ~~litigation or interference proceedings~~our patents and patent applications may fail and, even if successful, may result in substantial costs and distract our management and other employees. We may not be able to prevent, alone or with our licensors, misappropriation of our intellectual property rights, particularly in countries where the laws may not protect those rights as fully as in the United States.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. There could also be public announcements of the results of hearings, motions or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, itthese perceptions could have a material adverse effect on the price of our common stock.

We may be subject to claims challenging the inventorship or ownership of our patents and other intellectual property.

We may also be subject to claims that third parties, including but not limited to, former employees and collaborators, ~~or other third parties~~ have an ownership interest in our patents or other intellectual property. In the future, we may have ownership disputes arising, for example, from conflicting obligations of consultants or others who are involved in developing our product candidates. Litigation may be necessary to defend against these and other claims challenging inventorship or ownership. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights, such as the exclusive ownership of, or the right to use, valuable intellectual property. Such an outcome could have a material adverse effect on our business. Even if we are

successful in defending against such claims, litigation or arbitration could result in substantial costs and be a distraction to management and other employees.

Issued patents covering our product candidates could be found invalid or unenforceable if challenged in court.

If we or one of our licensing partners initiated legal proceedings against a third party to enforce a patent covering one of our product candidates or the use or manufacture thereof, the defendant could counterclaim that the patent covering our product candidate is invalid and/or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity and/or unenforceability are commonplace. Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including ~~lack of~~utility, written description, novelty, ~~obviousness~~non-obviousness or ~~non-enablement. Grounds for an unenforceability assertion could~~enablement. Additionally, in the United States, a patent can be ~~an allegation that~~deemed unenforceable if someone connected with the prosecution of ~~the~~a patent application intentionally withheld materially relevant information from the ~~U.S. PTO,~~USPTO, or ~~made a misleading statement,~~intentionally mislead the USPTO during prosecution. ~~Third parties may also raise similar claims before administrative bodies~~Third-party challenges to the validity and/or enforceability of a patent can occur in courts in the United States or abroad, ~~even outside the context of litigation. Such mechanisms include~~or in pre- or post-grant proceedings in some foreign patent offices (e.g., but not limited to re-examination, post grant review, ~~and equivalent proceedings in foreign jurisdictions (e.g.,~~inter parties review, or opposition

proceedings). Such proceedings could result in the revocation of, or amendment to, our patents in such a way that they no longer cover our product candidates. The outcome following legal assertions of invalidity and unenforceability is unpredictable. With respect to the validity question, for example, we cannot be certain that there is no invalidating prior art, of which we and the patent examiner were unaware during prosecution. If a defendant were to prevail on a legal assertion of invalidity and/or unenforceability ~~we would lose at least part, and perhaps all,~~ of one of our patents for a product candidate, this could substantially affect our ability to protect that product candidate in the country in which the patent ~~protection on our product candidates.~~was issued. Such a loss of patent protection ~~would~~could have a material adverse impact on our business.

We may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties or that our employees have wrongfully used or disclosed alleged trade secrets of their former employers.

As is common in the biotechnology and pharmaceutical industry, we employ individuals who were previously employed at universities or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Although we try to ensure that our employees, consultants and independent contractors do not use the proprietary information or know-how of others in their work for us, we may be subject to claims that we or our employees, consultants or independent contractors have inadvertently or otherwise used or disclosed intellectual property, including trade secrets or other proprietary information, of any of our employee’s former employer or other third parties. Litigation may be necessary to defend against these claims. If we fail in defending any such claims, in addition to paying monetary damages and suffering reputational harm, we may lose valuable intellectual property rights or personnel, which could adversely impact our business. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

We may not be able to protect our intellectual property rights throughout the world.

Filing, prosecuting and defending patents on our product candidates in all countries throughout the world would be prohibitively expensive, and our intellectual property rights in some countries outside the United States can be less extensive than those in the United States. In addition, the laws of some foreign countries do not protect intellectual property rights to the same extent as federal and state laws in the United States. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the United States, or from selling or importing products made using our inventions in and into the United States or other jurisdictions. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own products and may also export infringing products to territories where we have patent protection, but enforcement is not as strong as that in the United States. These products may compete with any products that we may develop and commercialize, and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents, trade secrets, and other intellectual property protection, particularly those relating to biotechnology and pharmaceutical products, which could make it difficult for us to stop the infringement of our patents or marketing of competing products in violation of our proprietary rights generally. Proceedings to enforce our patent rights in foreign jurisdictions, whether or not successful, could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly and our patent applications at risk of not issuing and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate and the damages or other remedies awarded, if any, may not be commercially meaningful. Accordingly, our efforts to enforce our intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from these intellectual property rights.

If the market opportunities for our product candidates are smaller than we believe they are or if we are unable to market our products to expanded patient populations, our revenues may be adversely affected, and our business may suffer.

We focus our research and product development efforts on treatments for ~~heritable cardiomyopathies,~~cardiac muscle contraction and our targeted indications ~~are rare genetic diseases.~~affect relatively small populations. In particular, we estimate that approximately 630,000 people in the United States have a form of HCM, and that approximately 360,000 people in the United States have a form of genetic DCM. Our projections of both the number of people who have these diseases, as well as the subset of people with these diseases who have the potential to benefit from treatment with our product candidates, are based on estimates derived from primary research with physicians and payors, analysis of medical journals and peer-reviewed literature, the work of third-party consultants and other publicly- or non-publicly-available data sources. These estimates may prove to be incorrect and new studies may change the estimated incidence or prevalence of our targeted disease indications. The number of patients in the United States, Europe and elsewhere may turn out to be lower than expected, may not be otherwise amenable to treatment with our products, and new patients may become increasingly difficult to identify or gain access to, all of which would adversely affect our results of operations and our business.

Additionally, because the target patient populations of our product candidates are small, we must be able to successfully identify patients and achieve a significant market share to achieve or maintain profitability and growth. Although we plan to use SHaRe to identify and select patients who are suitable for treatment with our products, if approved, we may not be able to identify or target a sufficient number of patients through SHaRe or our sales and marketing efforts to achieve the necessary market share.

Even if any of our product candidates receive marketing approval, they may fail to achieve the degree of market acceptance by physicians, patients, healthcare payors and others in the medical community necessary for commercial success.

If any of our product candidates receive marketing approval, they may nonetheless fail to gain sufficient market acceptance by physicians, patients, healthcare payors and others in the medical community. For example, current cardiovascular disease treatments such as beta blockers, non-dihydropyridine calcium channel blockers and disopyramide are well-established in the medical community, and doctors may continue to rely on these treatments. If our product candidates do not achieve an adequate level of acceptance, we may not generate significant product revenues and we may not become profitable. The degree of market acceptance of our product candidates, if approved for commercial sale, will depend on a number of factors, including:

Any failure to achieve or maintain sufficient market acceptance of mavacamten ~~MYK-491~~, danicamtiv or any of our other product candidates, if approved, could significantly harm our business, prospects, financial condition and results of operations.

IfWe are currently establishing a sales and marketing organization; however, if we are unable to ~~establish sales and marketing capabilities or~~ enter into agreements with third parties to sell and market our drug candidates, we may not be successful in commercializing our drug candidates if and when they are approved, and we may not be able to generate any revenue.

We have limited experience in the sale, marketing or distribution of drugs. To achieve commercial success for any approved drug candidate for which we retain sales and marketing responsibilities, we must build our sales, marketing, managerial, and other non‑technical capabilities or make arrangements with third parties to perform these services. In the future, we may choose to build a focused sales and marketing infrastructure to sell, or participate in sales activities with our collaborators for some of our drug candidates if and when they are approved.

There are risks involved with both establishing our own sales and marketing capabilities and entering into arrangements with third parties to perform these services. For example, recruiting and training a sales force is expensive and time-consuming and could delay any drug launch. If the commercial launch of a drug candidate for which we recruit a sales force and establish marketing capabilities is delayed or does not occur for any reason, we would have prematurely or unnecessarily incurred these commercialization expenses. This may be costly, and our investment would be lost.

Factors that may inhibit our efforts to commercialize our drug candidates on our own include:

If we enter into arrangements with third parties to perform sales, marketing and distribution services, our drug revenues or the profitability of these drug revenues to us are likely to be lower than if we were to market and sell any drug candidates that we develop ourselves. In addition, we may not be successful in entering into arrangements with third parties to sell and market our ~~product~~drug candidates weor may be unable to ~~generate~~do so on terms that are favorable to us. We likely will have little control over such third parties, and any ~~revenues.~~

~~We have no experience~~of them may fail to devote the necessary resources and attention to sell and market our drug candidates effectively. If we do not establish sales and marketing ~~or selling our product candidates. To~~capabilities successfully, ~~commercialize any products that may result from our development programs, we will need to develop these capabilities,~~ either on our own or in collaboration with others. We may enter into collaborations with other entities to utilize their mature marketing and distribution capabilities, but we may be unable to enter into marketing agreements on favorable terms, if at all. If our future collaborations do not commit sufficient resources to commercialize our future products, if any, and we are unable to develop the necessary marketing capabilities on our own,third parties, we will not be ~~unable to generate sufficient product revenue to sustain~~successful in commercializing our ~~business. We~~drug candidates. Further, our business, results of operations, financial condition and prospects will be competing with many companies that currently have extensive and well-funded marketing and sales operations. Without an internal team or the support of a third party to perform marketing and sales functions, we may be unable to compete successfully against these more established companies.materially adversely affected.

The insurance coverage and reimbursement status of newly-approved products targeting small patient populations is uncertain. Failure to obtain or maintain adequate coverage and reimbursement for our product candidates, if approved, could limit our ability to market those products and decrease our ability to generate revenue.

The availability and extent of reimbursement by governmental and private payors is essential for most patients to be able to afford expensive treatments, such as endothelin receptor antagonists used in the treatment of certain cardiovascular diseases. Sales of our product candidates will depend substantially, both domestically and abroad, on the extent to which the costs of our product candidates will be paid by health maintenance, managed care, pharmacy benefit and similar healthcare management organizations, or reimbursed by government health administration authorities, private health coverage insurers and other third-party payors. Additionally, therapies directed at small patient populations, such as our product candidates, may be more expensive, and reimbursement options for these therapies may be more limited. If reimbursement or coverage is not available, or is available only to limited levels, we may not be able to successfully commercialize our product candidates. Even if coverage is provided, the approved reimbursement amount may not be high enough to allow us to establish or maintain pricing sufficient to realize a sufficient return on our investment.

There is significant uncertainty related to the insurance coverage and reimbursement of newly approved products and for products whose targeted patient populations are small. In the United States, the principal decisions about reimbursement for new medicines are typically made by the Centers for Medicare & Medicaid Services (“~~CMS”)~~(CMS), an agency within the U.S. Department of Health and Human Services, as CMS decides whether and to what extent a new medicine will be covered and reimbursed under Medicare. Private payors tend to follow CMS to a substantial degree. It is difficult to predict what CMS or third-party payors will decide with respect to reimbursement and coverage for fundamentally novel products such as ours, as there is no body of established practices and precedents for these new products. Reimbursement agencies in Europe may be more conservative than CMS.

Outside the United States, international operations are generally subject to extensive governmental price controls and other market regulations, and we believe the increasing emphasis on cost-containment initiatives in Europe, Canada, and other countries may put pressure on the pricing and usage of our product candidates. In many countries, the prices of medical products are subject to varying price control mechanisms as part of national health systems. In general, the prices of medicines under such systems are substantially lower than in the United States. Other countries allow companies to fix their own prices for medicines but monitor and control company profits. Additional foreign price controls or other changes in pricing regulation could restrict the amount that we are able to charge for our product candidates. Accordingly, in markets outside the United States, the reimbursement for our products may be reduced compared with the United States and may be insufficient to generate commercially reasonable revenues and profits.

Moreover, increasing efforts by governmental and third-party payors, in the United States and abroad, to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for new products approved and, as a result, they may not cover or provide adequate payment for our product candidates. We expect to experience pricing pressures in connection with the sale of any of our product candidates, due to the trend toward managed healthcare, the increasing influence of health maintenance organizations and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs and surgical procedures and other treatments, has become very intense. As a result, increasingly high barriers are being erected to the entry of new products.

While we have received orphan drug designation for our most advanced drug candidate, mavacamten, for the treatment of symptomatic obstructive HCM, we may seek orphan drug designation for some of our other drug candidates. However, we may be

~~Risk~~unsuccessful in obtaining or may be unable to maintain the benefits associated with orphan drug designation, including the potential for market exclusivity.

The FDA has granted orphan drug designation to mavacamten for the treatment of symptomatic obstructive HCM. As part of our business strategy, we may seek orphan drug designation for some of our other drug candidates, and we may be unsuccessful. Regulatory authorities in some jurisdictions, including the United States, may designate drugs for relatively small patient populations as orphan drugs. Under the Orphan Drug Act, the FDA may designate a drug as an orphan drug if it is a drug intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals annually in the United States, or a patient population greater than 200,000 in the United States where there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the United States. In the United States, orphan drug designation entitles a party to financial incentives such as opportunities for grant funding towards clinical trial costs, tax advantages and user‑fee waivers.

Generally, if a drug with an orphan drug designation subsequently receives the first marketing approval for the indication for which it has such designation, the drug is entitled to a period of marketing exclusivity, which precludes the FDA from approving another marketing application for the same drug and indication for that time period, except in limited circumstances. The applicable period is seven years in the United States. Even if we obtain orphan drug exclusivity for a drug, that exclusivity may not effectively protect the designated drug from competition because different drugs can be approved for the same condition. Even after an orphan drug is approved, the FDA can subsequently approve the same drug for the same condition if the FDA concludes that the later drug is clinically superior in that it is shown to be safer, more effective or makes a major contribution to patient care. In addition, a designated orphan drug may not receive orphan drug exclusivity if it is approved for a use that is broader than the indication for which it received orphan designation. Moreover, orphan drug exclusive marketing rights in the United States may be lost if the FDA later determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantity of the drug to meet the needs of patients with the rare disease or condition. Orphan drug designation neither shortens the development time or regulatory review time of a drug nor gives the drug any advantage in the regulatory review or approval process. While we might seek orphan drug designation for our other drug candidates in addition to mavacamten for the treatment of symptomatic oHCM, we may never receive such designations. Even if we receive orphan drug designation for any of our drug candidates, there is no guarantee that we will enjoy the benefits of those designations.

If we participate in and then fail to comply with our reporting and payment obligations under governmental pricing programs in the United States, we could be subject to additional reimbursement requirements, penalties, sanctions and fines which could have a material adverse effect on our business financial condition, results of operations and growth prospects.

With the approval of any product candidate, we anticipate that we may participate in a number of federal and state government pricing programs in the United States in order to obtain coverage for the product by certain government healthcare programs. These programs would generally require us to pay rebates or provide discounts to certain private purchasers or government payers in connection with our products when dispensed to beneficiaries of these programs. In some cases, such as with the Medicaid Drug Rebate Program, the rebates are based on pricing and rebate calculations that we report on a monthly and quarterly basis to the government agencies that administer the programs. The terms, scope and complexity of these government pricing programs change frequently. We may also have reimbursement obligations or be subject to penalties if we fail to provide timely and accurate information to the government, pay the correct rebates or offer the correct discounted pricing. Changes to the price reporting or rebate requirements of these programs would affect our obligations to pay rebates or offer discounts. Responding to current and future changes may increase our costs and the complexity of compliance, will be time-consuming, and could have a material adverse effect on our results of operations.

The outbreak of the novel strain of coronavirus, SARS-CoV-2, which causes COVID-19, could adversely impact our business.

The outbreak of the novel strain of coronavirus, SARS-CoV-2, which causes coronavirus disease 2019 (COVID-19) has evolved into a global pandemic. In response to the spread of COVID-19, we have closed our executive offices with our administrative employees continuing their work outside of our offices, and restricted on-site staff to only those required to maintain the facilities and equipment.

As a result of the COVID-19 outbreak, or similar pandemics, we have and may in the future experience disruptions that could severely impact our business, research and clinical development activities, including:

In addition, the trading prices for our common stock and other biopharmaceutical companies have been highly volatile as a result of the COVID-19 pandemic. As a result, we may face difficulties raising capital through equity or debt financings, or such financing transactions may be on unfavorable terms.

The COVID-19 outbreak continues to rapidly evolve, and it is unknown how long disruptions to our research, clinical development and other business operations resulting from the COVID-19 pandemic, including any disruptions relating to the ultimate geographic spread of the disease, the duration of the outbreak, travel restrictions and actions by businesses and governmental authorities to contain the outbreak, such as quarantines or “stay at home” orders and business closures, will continue. However, any prolonged disruption could have a material adverse impact our business, financial condition and results of operations, and we will continue to monitor the situation closely.

To the extent the COVID-19 pandemic adversely affects our business and financial results, it may also have the effect of heightening many of the other risks described in this ‘‘Risk Factors’’ section, such as those relating to our clinical development operations, the supply chain for our ongoing and planned clinical trials, and our need to raise additional capital to support our operations.

We may be subject to healthcare, health information privacy and security laws, regulation and enforcement, and our failure to comply with these laws could harm our results of operations and financial conditions.

Although we do not currently have any products on the market, if we obtain FDA approval for any of our product candidates and begin commercializing those products in the United States, our operations may be directly, or indirectly through our customers and third-party payors, subject to various U.S. federal and state fraud and abuse, patient privacy ~~laws~~ and other healthcare regulatory laws, and to additional healthcare, statutory and regulatory requirements and enforcement by foreign regulatory authorities in jurisdictions in which we conduct our business. Healthcare providers, physicians and ~~others~~other healthcare market participants play a primary role in the recommendation and prescription of any ~~products~~product for which we obtain marketing approval. These laws may impact, among other things, our proposed sales, marketing and education programs and constrain the business of financial arrangements and relationships with healthcare providers, physicians and other parties through which we market, sell and distribute our products for which we obtain marketing approval. There are ambiguities as to what is required to comply with these requirements, and if we fail to comply with any applicable federal, state or foreign legal requirement, we could be subject to penalties.

Regulators globally are also imposing greater monetary fines for privacy violations. For example, in 2016, the European Union adopted a new regulation governing data practices and privacy called the General Data Protection Regulation (GDPR) which became effective on May 25, 2018. The GDPR applies to any company established in the European Union as well as to those outside the European Union if they collect and use personal data in connection with the offering goods or services to individuals in the European Union or the monitoring of their behavior. The GDPR enhances data protection obligations for processors and controllers of personal data, including, for example, special protections for “sensitive information” such as health and genetic information, expanded disclosures about how personal information is to be used, limitations on retention of information, mandatory data breach notification

requirements and onerous new obligations on service providers. Non-compliance with the GDPR may result in monetary penalties of up to €20 million or 4% of worldwide revenue, whichever is higher. The GDPR and other changes in laws ~~that may affect~~or regulations associated with the enhanced protection of certain types of personal data, such as healthcare data or other sensitive information, could greatly increase our cost of developing or commercializing our product candidates or impair our ability to ~~operate include:~~

Efforts to ensure that our business arrangements with third parties will comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices may not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of the laws described above or any other governmental laws and regulations that may apply to us, we may be subject to significant penalties, including civil, criminal and administrative penalties, damages, fines, exclusion from U.S. government funded healthcare programs, such as Medicare and Medicaid, and the curtailment or restructuring of our operations. If any of the physicians or other providers or entities with whom we expect to do business is found not to be in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs and imprisonment. If any of the above occur, it could adversely affect our ability to operate our business and our results of operations.

We face significant competition from other biotechnology and pharmaceutical companies, and our operating results will suffer if we fail to compete effectively.

Our competitors may develop drugs that are less expensive, safer, or more effective, which may diminish or eliminate the commercial success of any drugs that we may commercialize.

We will compete for market share against large pharmaceutical and biotechnology companies and smaller companies that are collaborating with larger pharmaceutical companies, new companies, academic institutions, government agencies and other public and private research organizations. Many of these competitors, either alone or together with their partners, may develop new drug candidates that will compete with ours, as these competitors may, and in certain cases do, operate larger research and development programs or have substantially greater financial resources than we do. Our competitors may also have significantly greater experience in:

If our competitors market drugs that are less expensive, safer or more effective than our potential drugs, or that reach the market sooner than our potential drugs, we may not achieve commercial success. In addition, the life sciences industry is characterized by rapid technological change. Because our research approach integrates many technologies, it may be difficult for us to stay abreast of the rapid changes in each technology. If we fail to stay at the forefront of technological change, we may be unable to compete effectively. Our competitors may render our technologies obsolete by advances in existing technological approaches or the development of new or different approaches, potentially eliminating the advantages in our drug discovery process that we believe we derive from our research approach and proprietary technologies.

In the field of heart failure drug development, our principal competitors include Amgen Inc., AstraZeneca plc, Bayer AG, Bristol-Myers Squibb Company, C.H. Boehringer Sohn AG & Co. KG, Eli Lilly and Company, Novartis AG and Takeda Pharmaceutical Company Limited. Specific to our initial drug discovery and development focus areas, we believe that Cytokinetics, Inc., Takeda Pharmaceutical Company Limited and Novartis AG have ongoing programs in HCM and that Novartis AG, Pfizer Inc., Tenaya Therapeutics, Berlin Cures, and Zensun (Shanghai) Sci. & Tech. Co., Ltd. have ongoing programs in DCM. Additionally, there may be other companies pursuing therapeutic candidates from which we face current or future competition.

Public opinion and heightened regulatory scrutiny of precision medicine for the treatment of cardiovascular disease may impact public perception of our product candidates or adversely affect our ability to conduct our business or obtain regulatory approvals for our product candidates.

Precision medicine remains a novel technology, particularly in the field of cardiovascular disease, with no products approved to date in the United States that are specifically targeted at correcting the underlying biomechanical defects in cardiac contractility associated with HCM and DCM. Public perception may be influenced by claims that these therapies are unproven or unsafe, and our product candidates may not gain the acceptance of the public or the medical community. In particular, our success will depend upon physicians, who specialize in the treatment of those diseases that our product candidates target, prescribing treatments that involve the use of our product candidates in lieu of, or in addition to, existing treatments they are already familiar with and for which greater clinical data may be available. More restrictive government regulations or negative public opinion could have an adverse effect on our business or financial condition and may delay or impair the development and commercialization of our product candidates or demand for any products we may develop. Adverse events in our clinical trials, even if not ultimately attributable to our product candidates, and the resulting publicity, could result in increased governmental regulation, unfavorable public perception, potential regulatory delays in the testing or approval of our product candidates, stricter labeling requirements for those product candidates that are approved and a decrease in demand for any such product candidates.

Healthcare legislative ~~reform measures~~changes may have a material adverse effect on our business and results of operations.

In the United States, the ~~EU,~~European Union and other foreign jurisdictions, there have been a number of legislative and regulatory changes to the healthcare system that could affect our future results of operations. In particular, there have been and continue to be a number of initiatives at the United States federal and state levels that seek to reduce healthcare costs and improve the quality of healthcare. For example, ~~ACA changes~~the Patient Protection and Affordable Care Act (ACA) changed the way healthcare is financed by both governmental and private insurers and significantly ~~impacts~~impacted the U.S. pharmaceutical and biotechnology industries. Since its enactment, there have been many judicial, Presidential, and Congressional challenges to numerous aspects of the ACA, ~~among other things, subjects biologic products to potential competition~~and the long ranging effects of these challenges on reimbursement by ~~lower-cost biosimilars, addresses a new methodology by which rebates owed by manufacturers under~~third-party payors, the ~~Medicaid Drug Rebate Program~~viability of the ACA marketplace, providers, and potentially, our business are calculated for drugs that are inhaled, infused, instilled, implanted or injected, increases the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program and extends the rebate program to individuals enrolled in Medicaid managed care organizations, establishes annual fees and taxes on manufacturers of certain branded prescription drugs and biologic products, and a new Medicare Part D coverage gap discount program, in which manufacturers must agree to offer 50% point-of-sale discounts off negotiated prices of applicable brand drugs to eligible beneficiaries during their coverage gap period, as a condition for the manufacturer’s outpatient drugs to be covered under Medicare Part D. Atunknown at this ~~time,~~time. In addition, the full ~~effect that~~impact of the ACA, any law repealing and/or replacing elements of it, and the political uncertainty surrounding any ~~successor laws and regulations would have~~repeal or replacement legislation on our business remains unclear.

Moreover, payment methodologies may be subject to changes in healthcare legislation and regulatory initiatives. For example, CMS may develop new payment and delivery models, such as bundled payment models. The U.S. federal government has set a goal of moving 50% of Medicare payments into these “Alternative Payment Models” by the end of 2018. In addition, recently there has been heightened governmental scrutiny over the manner in which drug manufacturers set prices for their commercial products. We expect that additional U.S. federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that the U.S. federal government will pay for healthcare products and services, which could result in reduced demand for our product candidates or additional pricing pressures.

In addition, other legislative changes have been proposed and adopted in the United States since ACA was enacted. On August 2, 2011, the Budget Control Act of 2011, among other things, created measures for spending reductions by Congress. A Joint Select Committee on Deficit Reduction, tasked with recommending a targeted deficit reduction of at least $1.2 trillion for the years 2013 through 2021, was unable to reach required goals, thereby triggering the legislation’s automatic reduction to several government programs. This includes aggregate reductions of Medicare payments to providers of 2% per fiscal year. These reductions went into effect on April 1, 2013 and, due to subsequent legislative amendments to the statute, will remain in effect through 2025 unless additional Congressional action is taken. On January 2, 2013, the American Taxpayer Relief Act of 2012 was signed into law, which, among other things, further reduced Medicare payments to several types of providers, including hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years. These ~~new~~ laws may result in additional reductions in Medicare and other health care funding, which could have a material adverse effect on our customers and accordingly, our financial operations.

Moreover, payment methodologies may be subject to changes in healthcare legislation and regulatory initiatives. For example, CMS may develop new payment and delivery models, such as bundled payment models. The U.S. federal government has set a goal of moving 50% of Medicare payments into these “Alternative Payment Models” by the end of 2018. ~~In addition, recently there has been heightened governmental scrutiny over the manner in which drug manufacturers set prices for their commercial products.~~We expect that additional U.S. federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that the U.S. federal government will pay for healthcare products and services, which could result in reduced demand for our product candidates or additional pricing pressures.

Our future success depends on our ability to retain our key executives, employees and consultants ~~including our scientific advisors and founders,~~ and to attract, retain and motivate qualified personnel.

We are highly dependent on our scientific advisors ~~and founders~~ and the principal members of our executive team, the loss of whose services may adversely impact the achievement of our objectives. While we have entered into employment agreements with each of our executive officers, any of them could leave our employment at any time, as all of our employees are “at will” employees. Recruiting and retaining other qualified employees, consultants and advisors for our business, including scientific and technical personnel, will also be critical to our success. There is currently a shortage of skilled executives and scientific experts in our industry, which is likely to continue. As a result, competition for skilled personnel is intense and the turnover rate can be high. We may not be able to attract and retain personnel on acceptable terms given the competition among numerous pharmaceutical and biotechnology companies, as well as from academic and research institutions, for individuals with similar skill sets. In addition, any failure of our programs to succeed in preclinical studies or clinical trials may make it more challenging to recruit and retain qualified personnel. The inability to recruit or the loss of the services of any executive, key employee, consultant or advisor may impede the progress of our research, development and commercialization objectives.

We will need to expand our organization and we may experience difficulties in managing this growth, which could disrupt our operations.

As of ~~September 30, 2017,~~March 31, 2020, we had 98246 full-time employees. As we mature, we expect to expand our full-time employee base and to hire more consultants and contractors. Over the next several years, we expect to expand our development, regulatory and sales and marketing capabilities, and as a result, we may encounter difficulties in managing our growth, which could disrupt our operations. Our management may need to divert a disproportionate amount of its attention away from our day-to-day activities and devote a substantial amount of time to managing these growth activities. We may not be able to effectively manage the expansion of our operations, which may result in weaknesses in our infrastructure, operational mistakes, loss of business opportunities, loss of employees and reduced productivity among remaining employees. Our expected growth could require significant capital expenditures and may divert financial resources from other projects, such as the development of additional product candidates. If our management is unable to effectively manage our growth, our expenses may increase more than expected, our ability to generate and/or grow revenues could be reduced, and we may not be able to implement our business strategy. Our future financial performance and our ability to commercialize product candidates and compete effectively will depend, in part, on our ability to effectively manage any future growth.

We may expend our limited resources to pursue a particular product candidate or indication and fail to capitalize on product candidates or indications that may be more profitable or for which there is a greater likelihood of success.

Because we have limited financial and managerial resources, we focus on research programs and product candidates that we identify for specific indications. As a result, we may forego or delay pursuit of opportunities with other product candidates or for other indications that later prove to have greater commercial potential. Our resource allocation decisions may cause us to fail to capitalize on viable commercial medicines or profitable market opportunities. Our spending on current and future research and development programs and product candidates for specific indications may not yield any commercially viable medicines. If we do not accurately evaluate the commercial potential or target market for a particular product candidate, we may relinquish valuable rights to that product candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to such product candidate.

Inadequate funding for the FDA, the SEC and other government agencies could hinder their ability to hire and retain key leadership and other personnel, prevent new products and services from being developed or commercialized in a timely manner or otherwise prevent those agencies from performing normal business functions on which the operation of our business may rely, which could negatively impact our business.

The ability of the FDA to review and approve new products can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory, and policy changes. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of the SEC and other government agencies on which our operations may rely, including those that fund research and development activities, is subject to the political process, which is inherently fluid and unpredictable.

Disruptions at the FDA and other agencies may also slow the time necessary for new drugs to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. For example, over the last several years, including most recently from December 22, 2018 to January 25, 2019, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA and the SEC, have had to furlough critical FDA, SEC and other government employees and stop critical activities. If a prolonged government shutdown occurs, it could significantly impact the ability of the FDA to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

Our anticipated international operations may expose us to business, regulatory, political, operational, financial, pricing and reimbursement and economic risks associated with doing business outside of the United States.

We have atwo wholly-owned subsidiaries: an Australian subsidiary through which we conduct clinical trials in ~~Australia.~~Australia and a Dutch subsidiary through which we intend to determine the feasibility of commercialization in the EU. Our business strategy also contemplates potential additional international operations as we seek to continue the development of mavacamten ~~MYK-491~~, danicamtiv, MYK-224 and other product candidates that we have or may identify, seek regulatory approval for our product candidates, and commercialize any product candidates that are approved outside the United States. If any product candidates for which we have retained worldwide commercial rights are approved, we may hire sales representatives and conduct physician and patient group outreach activities outside of the United States. Doing business internationally involves a number of risks, including but not limited to:

Any of these factors could significantly harm our future international expansion and operations and, consequently, our results of operations.

If we fail to comply with environmental, health and safety laws and regulations, we could become subject to fines or penalties or incur costs that could have a material adverse effect on the success of our business.

We are subject to numerous environmental, health and safety laws and regulations, including those governing laboratory procedures and the handling, use, storage, treatment and disposal of hazardous materials and wastes. Our operations involve the use of hazardous and flammable materials, including chemicals and biological materials. Our operations also produce hazardous waste products. We generally contract with third parties for the disposal of these materials and wastes. We cannot eliminate the risk of contamination or injury from these materials. In the event of contamination or injury resulting from our use of hazardous materials, we could be held liable for any resulting damages, and any liability could exceed our resources. We also could incur significant costs associated with civil or criminal fines and penalties.

Although we maintain workers’ compensation insurance to cover us for costs and expenses we may incur due to injuries to our employees resulting from the use of hazardous materials or other work-related injuries, this insurance may not provide adequate coverage against potential liabilities. In addition, we may incur substantial costs in order to comply with current or future environmental, health and safety laws and regulations. These current or future laws and regulations may impair our research, development or production efforts. Failure to comply with these laws and regulations also may result in substantial fines, penalties or other sanctions.

Our employees, independent contractors, principal investigators, CROs, consultants, vendors and collaboration partners may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements, which could have a material adverse effect on our business.

We are exposed to the risk that our employees, independent contractors, principal investigators, CROs, consultants, vendors and collaboration partners may engage in fraudulent conduct or other illegal activities. Misconduct by these parties could include intentional, reckless and/or negligent conduct or unauthorized activities that violate: (i) the regulations of the FDA, EMA and other regulatory authorities, including those laws that require the reporting of true, complete and accurate information to such authorities; (ii) manufacturing standards; (iii) federal and state data privacy, security, fraud and abuse and other healthcare laws and regulations in the United States and abroad; or (iv) laws that require the reporting of true, complete and accurate financial information and data. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, misconduct, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. Activities subject to these laws could also involve the improper use of information obtained in the course of clinical trials or creating fraudulent data in our preclinical studies or clinical trials, which could result in regulatory sanctions and cause serious harm to our reputation. It is not always possible to identify and deter misconduct by employees and other third parties, and the precautions we take to detect and prevent misconduct may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to comply with such laws or regulations. Additionally, we are subject to the risk that a person could allege such fraud or other misconduct, even if none occurred. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business and results of operations, including the imposition of significant civil, criminal and administrative penalties, damages, monetary fines, possible exclusion from participation in Medicare, Medicaid and other U.S. federal healthcare programs, contractual damages, reputational harm, diminished profits and future earnings, and curtailment of our operations, any of which could adversely affect our ability to operate our business and our results of operations.

Unfavorable global economic and political conditions could adversely affect our business, financial condition or results of operations.

Our ability to invest in and expand our business and meet our financial obligations, to attract and retain third-party contractors and collaboration partners and to raise additional capital depends on our operating and financial performance, which, in turn, is subject to numerous factors, including the prevailing economic and political conditions and financial, business and other factors beyond our control, such as the rate of unemployment, the number of uninsured persons in the United States, political influences and inflationary pressures. For example, an overall decrease in or loss of insurance coverage among individuals in the United States due to high levels of unemployment (particularly as a result of ~~unemployment,~~the COVID-19 pandemic), underemployment or the potential repeal of certain provisions of the ACA, may decrease the demand for healthcare services and pharmaceuticals. Additionally, the availability of healthcare services and resources is currently constrained due to the COVID-19 pandemic. If fewer patients are seeking medical care because they do not have insurance coverage or are unable to obtain medical care for their conditions due to resource constraints on the healthcare system, we may experience difficulties in any eventual commercialization of our product candidates and our business, results of operations, financial condition and cash flows could be adversely affected.

In addition, our results of operations could be adversely affected by general conditions in the global economy and in the global financial markets upon which biopharmaceutical companies such as us are dependent for sources of capital. In the past, global financial crises have caused extreme volatility and disruptions in the capital and credit markets. A severe or prolonged economic

downturn, including as a result of the COVID-19 pandemic, could result in a variety of risks to our business, including a reduced ability to raise additional capital when needed on acceptable terms, if at all, and weakened demand for our product candidates. A weak or declining economy could also strain our suppliers, possibly resulting in supply disruption. Any of the foregoing could harm our business and we cannot anticipate all of the ways in which the COVID-19 pandemic, current economic climate and financial market conditions could adversely impact our business.

We or the third parties upon whom we depend may be adversely affected by earthquakes, outbreak of disease or other natural disasters and our business continuity and disaster recovery plans may not adequately protect us from a serious disaster.

Earthquakes, outbreak of disease, or other natural disasters could severely disrupt our operations, and have a material adverse effect on our business, results of operations, financial condition and prospects. For example, our corporate headquarters is located in the San Francisco Bay Area, which in the past has experienced severe earthquakes. If a natural disaster, power outage, outbreak of disease, or other event occurred that prevented us from using all or a significant portion of our headquarters, that damaged critical infrastructure, such as the manufacturing facilities of our third-party contract manufacturers, or that otherwise disrupted operations, it may be difficult or, in certain cases, impossible for us to continue our business for a substantial period of time. Due to the effects of the COVID-19 pandemic, we have temporarily suspended the enrollment of new patients into our Phase 1 study of MYK-224 and the enrollment of existing patients from EXPLORER-HCM rolling over into the MAVA-LTE study. In addition, we have delayed the initiation of our Phase 3 VALOR-HCM study, Phase 2 HFpEF proof-of-concept study, and our Phase 2 study of danicamtiv in patients with genetic DCM. We will continue to closely monitor the evolving situation and expect to resume patient enrollment and to initiate delayed studies as soon as conditions safely permit. In addition, we may experience delays in the supply of drug product for our clinical trials as a result of disruptions to the operations of manufacturing facilities of some of our third-party contract manufacturers due to the COVID-19 pandemic. Any continued or subsequent measures taken by governmental authorities or businesses to contain the spread of COVID-19, or the perception that such measures may be required in the future should another outbreak occur, could adversely affect our business, financial condition or results of operations by limiting our contract manufacturers’ ability to manufacture product and forcing temporary closure of facilities that we rely upon. The extent to which COVID-19 impacts our results will depend on future developments, which are highly uncertain and cannot be accurately predicted, including new information which may emerge concerning the severity of COVID-19 and the actions to contain COVID-19 or treat its impact, among others. The disaster recovery and business continuity plans we have in place currently are limited and are unlikely to prove adequate in the event of a serious disaster or similar event. We may incur substantial expenses as a result of the limited nature of our disaster recovery and business continuity plans, which, particularly when taken together with our lack of earthquake insurance, could have a material adverse effect on our business.

Product liability lawsuits against us could cause us to incur substantial liabilities and could limit commercialization of any medicines that we may develop.

We face an inherent risk of product liability exposure related to the testing of our product candidates in human clinical trials and will face an even greater risk if we commercially sell any medicines that we may develop. If we cannot successfully defend ourselves against claims that our product candidates or medicines caused injuries, we could incur substantial liabilities. Regardless of merit or eventual outcome, liability claims may result in:

Although we maintain product liability insurance, including coverage for clinical trials that we sponsor, it may not be adequate to cover all liabilities that we may incur. We anticipate that we will need to increase our insurance coverage as we commence additional clinical trials and if we successfully commercialize any product candidates. The market for insurance coverage is increasingly expensive, and the costs of insurance coverage will increase as our clinical programs increase in size. We may not be able to maintain insurance coverage at a reasonable cost or in an amount adequate to satisfy any liability that may arise.

Our internal computer systems, or those of our third-party CROs or other contractors or consultants, may fail or suffer security breaches, which could result in a material disruption of our operations.

Despite the implementation of security measures, our internal computer systems and those of our third-party CROs and other contractors and consultants are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. While we have not experienced any such system failure, accident or security breach to date, if such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our programs. For example, the loss of clinical trial data for our product candidates could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. To the extent that any disruption or security breach results in a loss of or damage to our data or applications or other data or applications relating to our technology or product candidates, or inappropriate disclosure of confidential or proprietary information, we could incur liabilities and experience delays or disruptions to various aspects of our operations, including our financial reporting and the development of our product candidates.

Our ability to utilize our net operating loss carryforwards and certain other tax attributes may be limited.

We have incurred substantial losses during our history and do not expect to become profitable in the near future. To the extent that we continue to generate taxable losses, unused losses will carry forward to offset future taxable income, if any, until such unused losses expire. Under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended (~~the “Code”)~~(the Code) if a corporation undergoes an “ownership change,” generally defined as a greater than ~~50 percentage point~~50% change (by value) in its equity ~~ownership~~ownership over a rolling three-year period, the corporation’s ability to use its pre-change net operating loss carryforwards ~~(“NOLs”)~~(NOLs) and other pre-change tax attributes (such as research tax credits) to offset its post-change income or taxes may be limited. While we have determined that an ownership change occurred in April 2015 in connection with our Series B redeemable convertible preferred stock financing and in August 14, 2017 due to a subsequent stock offering, we do not believe that ~~this~~these ownership ~~change~~changes will result in the expiration of any of our existing NOLs prior to utilization. We may experience subsequent shifts in our stock ownership, some of which are outside our control. As a result, if we earn net taxable income, our ability to use our pre-change net operating loss carryforwards to offset U.S. federal taxable income may be subject to limitations, which could potentially result in increased future tax liability to us. In addition, at the state level, there may be periods during which the use of NOLs is suspended or otherwise limited, which could accelerate or permanently increase state taxes owed.

In addition, under the Tax Act, the amount of post-2017 NOLs that we are permitted to deduct in any taxable year is limited to 80% of our taxable income in such year, where taxable income is determined without regard to the NOL deduction itself. The Tax Act generally eliminates the ability to carry back any NOL to prior taxable years, while allowing post-2017 unused NOLs to be carried forward indefinitely. There is a risk that due to changes under the Tax Act, regulatory changes or other unforeseen reasons, our existing NOLs could expire or otherwise be unavailable to offset future income tax liabilities.

The United Kingdom’s withdrawal from the EU may have a negative effect on our business, global economic conditions, and financial markets.

As a result of the United Kingdom’s vote to leave the EU in March 2019 (known as Brexit), the EMA relocated its headquarters from London to Amsterdam. Since a significant proportion of the regulatory framework in the United Kingdom is derived from EU directives and regulations, Brexit could materially impact the regulatory regime with respect to the approval of product candidates, disrupt the manufacture of our products and product candidates in the United Kingdom or the EU, disrupt the import and export of active substances and other components of drug formulations, and disrupt the supply chain for clinical trial product and final authorized formulations. While negotiations continue regarding the terms of the United Kingdom’s withdrawal from the EU, the specific impact to the supervision, regulation and supply of medicines in the United Kingdom and Europe remain unclear. The cumulative effect of disruptions to the regulatory framework or supply chains may add considerably to the development lead time to, and expense of, marketing authorization and commercialization of products in the EU and/or the United Kingdom. In view of the uncertainty surrounding the Brexit implementation, we are unable to predict the effects of such disruption to the regulatory framework and supply chain in Europe.

The market price of our common stock has been and may continue to be highly volatile.

The market price of our common stock has experienced volatility since our IPO in October 2015 and is likely to continue to be volatile. Our stock price could be subject to wide fluctuations in response to a variety of factors, including the following:

In addition, companies trading in the stock market in general, and The NASDAQ Global Select Market (“~~NASDAQ”)~~(NASDAQ) in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. Broad market and industry factors, including the effects of the COVID-19 pandemic on the global economy, may negatively affect the market price of our common stock, regardless of our actual operating performance. In the past, following periods of volatility in the market, securities class-action litigation has often been instituted against companies. Such litigation, if instituted against us, could result in substantial costs and diversion of management’s attention and resources, which could materially and adversely affect our business, financial condition, results of operations and growth prospects.

Future sales and issuances of our common stock or rights to purchase common stock, including pursuant to our equity incentive plans, could result in additional dilution of the percentage ownership of our stockholders and could cause our stock price to fall.

Additional capital will be needed in the future to continue our planned operations. To the extent we raise additional capital by issuing equity securities, our stockholders may experience substantial dilution. We may sell common stock, convertible securities or other equity securities in one or more transactions at prices and in a manner we determine from time to time. If we sell common stock, convertible securities or other equity securities in more than one transaction, investors may be materially diluted by subsequent sales. These sales may also result in material dilution to our existing stockholders, and new investors could gain rights superior to our existing stockholders.

In addition, sales of a substantial number of shares of our outstanding common stock in the public market could occur at any time. These sales, or the perception in the market that the holders of a large number of shares of common stock intend to sell shares, could reduce the market price of our common stock. ~~Persons who were our stockholders prior to our IPO continue to hold a~~A substantial number of our outstanding shares of ~~our~~ common stock ~~that many of them are now able to sell in the public market. Significant portions of these shares~~ are held by a relatively small number of ~~stockholders.~~stockholders who are not subject to restrictions on trading. Sales by our stockholders of a substantial number of shares, or the expectation that such sales may occur, could significantly reduce the market price of our common stock.

We have also registered all shares of our common stock subject to options or other equity awards issued or reserved for future issuance under our equity incentive plans. As a result, these shares will be eligible for sale in the public market to the extent permitted by any applicable vesting requirements and the exercise of options, and restrictions under applicable securities laws. In addition, our directors, executive officers and certain affiliates have established or may in the future establish programmed selling plans under Rule 10b5-1 of the Securities Exchange Act of 1934, as amended, for the purpose of effecting sales of our common stock. If any of these events cause a large number of our shares to be sold in the public market, the sales could reduce the trading price of our common stock and impede our ability to raise future capital. Moreover, certain holders of our common stock have rights, subject to certain conditions, to require us to file registration statements covering their shares or to include their shares in registration statements that we may file for ourselves or other stockholders. In particular, we have filed a registration statement on Form S-3 registering for resale 9,184,352 shares of common stock held by entities affiliated with our major shareholder, Third Rock Ventures, which was declared effective by the SEC on July 21, 2017. These shares, together with any additional shares that we may register for resale, can be freely sold in the public market. If these additional shares are sold, or if it is perceived that they will be sold, in the public market, the trading price of our common stock could decline.

Pursuant to our 2015 Stock Option and Incentive Plan (the “2015 ~~Plan”)~~Plan), we are authorized to grant stock options and other equity-based awards to our employees, directors and consultants. Beginning on January 1, 2017, the number of shares available for future grant under the 2015 Plan will automatically increase each year by up to 4% of all shares of our capital stock outstanding as of December 31 of the prior calendar year, subject to the ability of our board of directors to take action to reduce the size of the increase in any given year. In addition, ~~pursuant to our 2015 Employee Stock Purchase Plan (the “2015 ESPP”), we initially reserved 255,000 shares for purchase by eligible employees. Beginning~~beginning on January 1, 2017 and ending on January 1, 2025, the number of shares available for future issuance under ~~the~~our 2015 ~~ESPP~~Employee Stock Purchase Plan (the 2015 ESPP) will automatically increase each year by up to the lesser of 3,000,000 shares of common stock or 1% of all shares of our capital stock outstanding as of December 31 of the prior calendar year, subject to the ability of our board of directors to take action to reduce the size of the increase in any given year. Currently, we plan to register the increased number of shares available for issuance under the 2015 Plan and the 2015 ESPP each year. If our board of directors elects to increase the number of shares available for future grant under these plans by the maximum amount each year, our stockholders may experience additional dilution, which could cause our stock price to fall.

Our principal stockholders and management own a significant percentage of our stock and will be able to exert significant control over matters subject to stockholder approval.

As of ~~October 31, 2017,~~April 22, 2020, our executive officers, directors, ~~five percent~~5% or greater stockholders and their affiliates beneficially own approximately ~~47.9%~~50.8% of our outstanding voting stock. These stockholders will have the ability to influence us through their ownership positions. These stockholders may be able to determine all matters requiring stockholder approval. For example, these stockholders, acting together, may be able to control elections of directors, amendments of our organizational documents, or approval of any merger, sale of assets, or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for our common stock that you may believe are in your best interest as one of our stockholders.

We have broad discretion in the use of our cash and cash equivalents and may not use them effectively.

Our management has broad discretion in the application of our existing cash and cash equivalents, and you will not have the opportunity to assess whether our existing cash and cash equivalents are being used appropriately. Because of the number and variability of factors that will determine our use of our existing cash and cash equivalents, their ultimate use may vary substantially from their currently intended use. The failure by our management to apply these funds effectively could harm our business. Pending their use, we may invest our cash and cash equivalents in short-term, investment-grade, interest-bearing securities. These investments may not yield a favorable return to our stockholders.

If securities or industry analysts do not publish research, or publish inaccurate or unfavorable research, about our business, our stock price and trading volume could decline.

The trading market for our common stock will depend, in part, on the research and reports that securities or industry analysts publish about us or our business. Securities and industry analysts may not publish an adequate amount of research on our company, which may negatively impact the trading price for our stock. In addition, if one or more of the analysts who cover us downgrade our stock or publish inaccurate or unfavorable research about our business, our stock price would likely decline. Further, if our operating results fail to meet the forecasts of analysts, our stock price would likely decline. If one or more of these analysts cease coverage of our company or fail to publish reports on us regularly, demand for our stock could decrease, which might cause our stock price and trading volume to decline.

We ~~are an “emerging growth company,” and we cannot be certain if the reduced reporting requirements applicable to emerging growth companies will make our common stock less attractive to investors.~~

We are an “emerging growth company,” as defined in the JOBS Act. For as long as we continue to be an emerging growth company, we may take advantage of exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies, including not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act”), reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. We will remain an emerging growth company until the earliest of (i) December 31, 2020, (ii) the last day of the fiscal year in which we have total annual gross revenue of $1.07 billion or more, (iii) the last day of the fiscal year in which we are deemed to be a large accelerated filer, which means the market value of our common stock that is held by non-affiliates exceeds $700.0 million as of the prior June 30^th and (iv) the date on which we have issued more than $1.07 billion in non-convertible debt during any three-year period before that time. Even after we no longer qualify as an emerging growth company, we may still qualify as a “smaller reporting company” which would allow us to take advantage of many of the same exemptions from disclosure requirements, including not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act (“Section 404”), and reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements. We cannot predict if investors will find our common stock less attractive because we may rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile.

Under the JOBS Act, emerging growth companies can also delay adopting new or revised accounting standards until such time as those standards apply to private companies. We have irrevocably elected not to avail ourselves of this exemption from new or revised accounting standards and, therefore, are subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.

We will continue to incur ~~increased~~significant costs as a result of operating as a public company, and our management is required to devote substantial time to existing and new public company compliance ~~initiatives.~~and reporting regulations.

As a public ~~company, and particularly after we are no longer an emerging growth~~ company, we incur and will continue to incur significant legal, accounting and other ~~expenses that we did not incur as a private company.~~expenses. In addition, the Sarbanes-Oxley Act and rules subsequently implemented by the SEC and NASDAQ have imposed various requirements on public companies, including establishment and maintenance of effective disclosure and financial controls and corporate governance practices. Our management and other personnel have devoted and will ~~need~~continue to devote a substantial amount of time to these compliance initiatives. Moreover, these rules and regulations have increased and will continue to increase our legal and financial compliance costs and will make some activities more time-consuming and costly. ~~For example, we expect that these rules and regulations may make it more difficult and more expensive for us to obtain director and officer liability insurance.~~

Pursuant to Section 404 of the Sarbanes-Oxley Act, we are required to furnish a report by our management on our internal control over financial reporting ~~starting~~ with our Annual Report on Form 10-K for ~~the~~each fiscal year ~~ending December 31, 2016. However, while we remain an emerging growth company, we will not be required~~and to obtain an attestation report on internal control over financial reporting issued by our independent registered public accounting firm. To achieve compliance with Section 404 within the prescribed period, we are and will continue to be engaged in a process to document and evaluate our internal control over financial reporting, which is both costly and challenging. In this regard, we will need to continue to dedicate internal resources, engage outside consultants and ~~adopt~~adhere to a detailed work plan to assess and document the adequacy of internal control over financial reporting, continue steps to improve control processes as appropriate, validate through testing that controls are functioning as documented and implement a continuous reporting and improvement process for internal control over financial reporting.

Despite our efforts, there is a risk that neither we nor our independent registered public accounting firm will be able to conclude within the prescribed timeframe that our internal control over financial reporting is effective as required by Section 404. This could impair our ability to produce timely and accurate consolidated financial statements and result in an adverse reaction in the financial markets due to a loss of confidence in the reliability of our consolidated financial statements.

In addition, as a public company we are required to file accurate and timely quarterly, annual and current reports with the SEC under the Exchange Act. Any failure to report our financial results on an accurate and timely basis could result in sanctions, lawsuits, delisting of our shares from The Nasdaq Global Select Market or other adverse consequences that would materially harm our business.

Our operating results may fluctuate significantly or may fall below the expectations of investors or securities analysts, each of which may cause our stock price to fluctuate or decline.

Our quarterly and annual operating results may fluctuate significantly in the future, which makes it difficult to predict our future operating results. Our net loss and other operating results will be affected by numerous factors, many of which are outside of our control and may be difficult to predict, including:

If our operating results fall below the expectations of investors or securities analysts, the price of our common stock could decline substantially. Furthermore, any fluctuations in our operating results may, in turn, cause the price of our stock to fluctuate substantially. Additionally, due to the unpredictability of our quarterly and annual operating results, we believe that period-to-period comparisons of our financial results are not necessarily meaningful and should not be relied upon as an indication of our future performance.

Because we do not anticipate paying any cash dividends on our capital stock in the foreseeable future, capital appreciation, if any, will be your sole source of gain.

We have never declared or paid cash dividends on our capital stock. We currently intend to retain all of our future earnings, if any, to finance the growth and development of our business. In addition, the terms of any future debt agreements may preclude us from paying dividends. As a result, capital appreciation, if any, of our common stock will be your sole source of gain for the foreseeable future.

In the past, securities class action litigation has often been brought against a company following a decline in the market price of its securities. This risk is especially relevant for us because biotechnology and pharmaceutical companies have experienced significant stock price volatility in recent years. If we face such litigation, it could result in substantial costs and a diversion of management’s attention and resources, which could harm our business.

Provisions in our amended and restated certificate of incorporation and amended and restated bylaws, as well as provisions of Delaware law, could make it more difficult for a third party to acquire us or increase the cost of acquiring us, even if doing so would benefit our stockholders or remove our current management.

Our amended and restated certificate of incorporation, amended and restated bylaws and Delaware law contain provisions that may have the effect of delaying or preventing a change in control of us or changes in our management. Our amended and restated certificate of incorporation and amended and restated bylaws include provisions that:

These provisions, alone or together, could delay or prevent hostile takeovers and changes in control or changes in our management.

In addition, because we are incorporated in Delaware, we are governed by the provisions of Section 203 of the Delaware General Corporation Law, which limits the ability of stockholders owning in excess of 15% of our outstanding voting stock to merge or combine with us.

Any provision of our amended and restated certificate of incorporation or amended and restated bylaws or Delaware law that has the effect of delaying or deterring a change in control could limit the opportunity for our stockholders to receive a premium for their shares of our common stock and could also affect the price that some investors are willing to pay for our common stock.

The following exhibits are filed or furnished as part of this Quarterly Report on Form 10-Q:

Exhibit
Number

Exhibit Description

Incorporated by
Reference From

Date

Number

Filed
Herewith

   3.1

Restated Certificate of Incorporation.

10-Q

11/18/2015

3.1

   3.2

Amended and Restated Bylaws.

S-1/A

10/13/2015

3.4

   4.1

Specimen Common Stock Certificate.

S-1/A

10/19/2015

4.1

  31.1

Certification of Principal Executive Officer Required Under Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as amended.

X

  31.2

Certification of Principal Financial Officer Required Under Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as amended.

X

  32.1*

Certification of Principal Executive Officer and Principal Financial Officer Required Under Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended, and 18 U.S.C. §1350.

X

101.INS

XBRL Instance Document.

X

101.SCH

XBRL Taxonomy Extension Schema Document.

X

101.CAL

XBRL Taxonomy Extension Calculation Linkbase Document.

X

101.DEF

XBRL Taxonomy Extension Definition Linkbase Document.

X

101.LAB

XBRL Taxonomy Extension Label Linkbase Document.

X

101.PRE

XBRL Taxonomy Extension Presentation Linkbase Document.

X

Exhibit

Number

Exhibit Description

Incorporated by

Reference From

Date

Number

Filed

Herewith

3.1

Restated Certificate of Incorporation.

10-Q

11/18/2015

3.1

3.2

Amended and Restated Bylaws.

S-1/A

10/13/2015

3.4

4.1

Specimen Common Stock Certificate.

S-1/A

10/19/2015

4.1

10.1

Common Stock Sales Agreement, by and between the Registrant and Cowen and Company, LLC dated January 3, 2020.

8-K

1/03/2020

1.1

10.2#

Amended and Restated 2015 Employee Stock Purchase Plan.

10.3#

Amended and Restated Non-Employee Director Compensation Policy.

31.1

Certification of Principal Executive Officer Required Under Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as amended.

31.2

Certification of Principal Financial Officer Required Under Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as amended.

32.1*

Certification of Principal Executive Officer and Principal Financial Officer Required Under Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended, and 18 U.S.C. §1350.

101.SCH

Inline XBRL Taxonomy Extension Schema Document.

101.CAL

Inline XBRL Taxonomy Extension Calculation Linkbase Document.

101.DEF

Inline XBRL Taxonomy Extension Definition Linkbase Document.

101.LAB

Inline XBRL Taxonomy Extension Label Linkbase Document.

101.PRE

Inline XBRL Taxonomy Extension Presentation Linkbase Document.

104

Cover Page Interactive Data File (formatted as inline XBRL with applicable taxonomy extension information contained in Exhibits 101.)

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Title of each class	Trading symbol(s)	Name of each exchange on which registered
Common Stock	MYOK	NASDAQ Global Select Market

Large accelerated filer	☐☒	Accelerated filer	☒☐
Non-accelerated filer	☐ ~~(Do not check if a smaller reporting company)~~	Smaller reporting company	☐
Emerging growth company	☒☐

	Page
PART I—FINANCIAL INFORMATION		3
Item 1. Unaudited Condensed Consolidated Financial Statements		3
Condensed Consolidated Balance Sheets as of ~~September 30, 2017~~March 31, 2020 and December 31, ~~2016 (unaudited)~~2019		3
Condensed Consolidated Statements of Operations and Comprehensive Loss for the ~~three~~Three Months Ended March 31, 2020 and ~~nine months ended September 30, 2017 and 2016 (unaudited)~~2019		4
Condensed Consolidated Statements of ~~Cash Flows~~Stockholders’ Equity for the ~~nine months ended September 30, 2017~~Three Months Ended March 31, 2020 and ~~2016 (unaudited)~~2019		5
~~Notes to~~ Condensed Consolidated ~~Financial~~ Statements ~~(unaudited)~~of Cash Flows for the Three Months Ended March 31, 2020 and 2019		6
Notes to Condensed Consolidated Financial Statements		7
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations		1516
Item 3. Quantitative and Qualitative Disclosures About Market Risk		2221
Item 4. Controls and Procedures		2221
PART II—OTHER INFORMATION		23
Item 1. Legal Proceedings		23
Item 1A. Risk Factors		23
~~Item 2. Unregistered Sales of Equity Securities and Use of Proceeds~~		52
~~Item 3. Defaults Upon Senior Securities~~		53
~~Item 4. Mine Safety Disclosures~~		53
~~Item 5. Other Information~~		53
Item 6. Exhibits		53
~~EXHIBIT INDEX~~		54
~~SIGNATURES~~		55
SIGNATURES		56

	Three Months Ended March 31,
	2020		2019
Operating lease cost	$	2,738	$	669
Variable lease cost		532		—
Total lease cost	$	3,270	$	669

Operating lease right-of-use assets obtained in exchange for lease obligations	$	52,630	$	1,095

Operating lease payments	$	2,174	$	727

Year ending December 31:	Amount
2020 (nine months remaining)	$	6,185
2021		8,449
2022		8,745
2023		9,051
2024		9,368
Thereafter		52,442
Total future lease payments		94,240
Less: imputed interest		(41,731	)
Total operating lease liabilities	$	52,509

	As of September 30,				As of March 31,
	2017		2016		2020		2019
Common stock subject to repurchase		127,524		517,219		—		5,003
Stock options to purchase common stock		3,289,677		2,034,777
Options and awards issued and outstanding						6,181,912		5,257,140

	Nine Months Ended September 30,
	2017			2016
	(in thousands)
Cash Flows from Continuing Operations:
Net cash used in operating activities	$	(3,207	)	$	(34,364	)
Net cash used in investing activities		(40,961	)		(854	)
Net cash provided by financing activities		135,555			73
Increase (decrease) in cash and cash equivalents	$	91,387		$	(35,145	)

	(a) Total Number of Shares Purchased (1)		(b) Average Price Paid per Share		(c) Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs		(d) Maximum Number (or Approximate Dollar Value) of Shares that May Yet Be Purchased Under the Plans or Programs
Period	(in thousands, except per share amounts)
July 1, 2017 through July 31, 2017		—	$	—		—		—
August 1, 2017 through August 31, 2017		15,589		1.51		—		—
September 1, 2017 through September 30, 2017		—		—		—		—
Total		15,589	$	1.51		—		—

Exhibit Number	Exhibit Description	Incorporated by Reference From	Date	Number	Filed Herewith

3.1	Restated Certificate of Incorporation.	10-Q	11/18/2015	3.1

3.2	Amended and Restated Bylaws.	S-1/A	10/13/2015	3.4

4.1	Specimen Common Stock Certificate.	S-1/A	10/19/2015	4.1

31.1	Certification of Principal Executive Officer Required Under Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as amended.				X

31.2	Certification of Principal Financial Officer Required Under Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as amended.				X

32.1*	Certification of Principal Executive Officer and Principal Financial Officer Required Under Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended, and 18 U.S.C. §1350.				X

101.INS	XBRL Instance Document.				X

101.SCH	XBRL Taxonomy Extension Schema Document.				X

101.CAL	XBRL Taxonomy Extension Calculation Linkbase Document.				X

101.DEF	XBRL Taxonomy Extension Definition Linkbase Document.				X

101.LAB	XBRL Taxonomy Extension Label Linkbase Document.				X

101.PRE	XBRL Taxonomy Extension Presentation Linkbase Document.				X

Date: ~~November 3, 2017~~	May 6, 2020	MYOKARDIA, INC.

	By:		/s/ Tassos Gianakakos
			Tassos Gianakakos
			President, Chief Executive Officer
			(Principal Executive Officer)


~~Date: November 3, 2017~~Date May 6, 2020	By:		/s/ ~~Jake Bauer~~Taylor Harris
			~~Jake Bauer~~Taylor Harris ~~Senior Vice President, Finance and Corporate Development~~Chief Financial Officer (Principal Financial and Accounting Officer)