Scholar Rock Holding (SRRK) 10-Q 8 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Nov. 01, 2018
Document and Entity Information
Entity Registrant Name	Scholar Rock Holding Corp
Entity Central Index Key	1,727,196
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		25,237,160
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 103,986	$ 56,461
Marketable securities		1,498
Prepaid expenses and other current assets	2,201	1,242
Total current assets	106,187	59,201
Property and equipment, net	2,626	2,181
Restricted cash	205	205
Other long-term assets		50
Total assets	109,018	61,637
Current liabilities:
Accounts payable	1,809	1,359
Accrued expenses	3,360	2,796
Deferred rent		228
Loan payable	578	641
Capital lease payable	14
Total current liabilities	5,761	5,024
Long-term portion of deferred rent	886	468
Long-term portion of loan payable		398
Long-term portion of capital lease payable	28
Warrant to purchase redeemable security		37
Total liabilities	6,675	5,927
Commitments and contingencies (Note 9)
Convertible preferred stock (Series A-1, A-2, A-3, A-4, B and C), $0.001 par value; no shares authorized, issued or outstanding as of September 30, 2018; 43,157,651 shares authorized and 43,135,911 shares issued and outstanding as of December 31, 2017 (aggregate liquidation preference of $109,561 as of December 31, 2017)		109,232
Stockholders’ equity (deficit):
Preferred stock, $0.001 par value; 10,000,000 and no shares authorized at September 30, 2018 and December 31, 2017, respectively; no shares issued and outstanding at September 30, 2018 and December 31, 2017, respectively
Common stock, $0.001 par value; 150,000,000 shares authorized and 25,241,766 shares issued and outstanding as of September 30, 2018; 60,000,000 shares authorized and 3,970,586 shares issued and outstanding as of December 31, 2017	25	4
Additional paid-in capital	194,204	4,001
Accumulated other comprehensive loss		(2)
Accumulated deficit	(91,886)	(57,525)
Total stockholders’ equity (deficit)	102,343	(53,522)
Total liabilities, convertible preferred stock and stockholders’ equity (deficit)	$ 109,018	$ 61,637

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
CONSOLIDATED STATEMENT OF FINANCIAL POSITION
Convertible preferred stock, par value		$ 0.001
Convertible preferred stock, shares authorized	0	43,157,651
Convertible preferred stock, shares issued	0	43,135,911
Convertible preferred stock, shares outstanding	0	43,135,911
Aggregate liquidation preference		$ 109,561
Preferred stock, par value	$ 0.001
Preferred stock, shares authorized	10,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	150,000,000	60,000,000
Common stock, shares issued	25,241,766	3,970,586
Common stock, shares outstanding	25,241,766	3,970,586

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME
Revenue			$ 0
Operating expenses:
Research and development	$ 8,061	$ 4,778	26,185	$ 13,057
General and administrative	3,173	1,164	8,947	3,514
Total operating expenses	11,234	5,942	35,132	16,571
Loss from operations	(11,234)	(5,942)	(35,132)	(16,571)
Other income (expense):
Interest income, net	472	9	828	32
Other expense, net		4	(56)	1
Total other income	472	13	772	33
Net loss	$ (10,762)	$ (5,929)	$ (34,360)	$ (16,538)
Net loss per share, basic and diluted (in dollars per share)	$ (0.44)		$ (2.72)
Net loss per unit, basic and diluted (in dollars per unit)		$ (3.70)		$ (10.32)
Weighted average common shares outstanding, basic and diluted (in shares)	24,310,681		12,647,032
Weighted average common units outstanding, basic and diluted (in units)		1,603,088		1,603,088
Comprehensive loss:
Net loss	$ (10,762)	$ (5,929)	$ (34,360)	$ (16,538)
Other comprehensive income
Unrealized gain on marketable securities		13	2	14
Total other comprehensive income		13	2	14
Comprehensive loss	$ (10,762)	$ (5,916)	$ (34,358)	$ (16,524)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net loss	$ (34,360)	$ (16,538)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	567	497
Equity-based compensation	3,057	689
Amortization of deferred rent	190	(155)
Deferred payroll tax credit	199
Other	95	35
Change in operating assets and liabilities:
Prepaid expenses and other current assets	(1,108)	(1,704)
Accounts payable	294	1,656
Accrued expenses	543	(159)
Net cash used in operating activities	(30,523)	(15,679)
Cash flows from investing activities:
Purchase of property and equipment	(791)	(247)
Sales and maturities of marketable securities	1,499	12,014
Net cash provided by investing activities	708	11,767
Cash flows from financing activities:
Principal payments on loan payable	(500)	(500)
Proceeds from initial public offering of common stock, net of issuance costs	77,839
Payment of capital lease obligation	(2)
Proceeds from stock option exercises	3
Proceeds from issuance of Series B convertible preferred units		4,285
Net cash provided by financing activities	77,340	3,785
Net increase (decrease) in cash and cash equivalents and restricted cash	47,525	(127)
Cash and cash equivalents and restricted cash, beginning of period	56,666	10,238
Cash and cash equivalents and restricted cash, end of period	104,191	10,111
Supplemental disclosure of non‑cash items:
Property and equipment purchases in accounts payable and accrued liabilities	177	59
Supplemental cash flow information:
Cash paid for interest	27	$ 41
Purchase under capital lease	$ 44

Nature of the Business

Nature of the Business	9 Months Ended
	Sep. 30, 2018
Nature of the Business
Nature of the Business	1. Nature of the Business Scholar Rock Holding Corporation (the “Company”) is a biopharmaceutical company focused on the discovery and development of innovative medicines for the treatment of serious diseases in which signaling by protein growth factors plays a fundamental role. The Company’s lead product candidate, SRK-015, is a selective inhibitor of the activation of the growth factor myostatin in skeletal muscle that the Company has advanced into clinical development for the treatment of spinal muscular atrophy. The Company was originally formed as a Delaware limited liability company in May 2012. In December 2017, the Company converted into a Delaware corporation through a series of transactions (the “Reorganization”). Its principal offices are in Cambridge, Massachusetts. Since its inception, the Company’s operations have focused on research and development of monoclonal antibodies that selectively inhibit activation of growth factors for therapeutic effect, as well as establishing the Company’s intellectual property portfolio and performing research and development activities. The Company has primarily financed its operations through various equity and debt financings, including the initial public offering of its common stock (the “IPO”) in May 2018. The Company is subject to a number of risks similar to other life science companies, including, but not limited to, successful discovery and development of its drug candidates, raising additional capital, development by its competitors of new technological innovations, protection of proprietary technology and regulatory approval and market acceptance of the Company’s products. During the second quarter of 2018, the Company completed its IPO, in which the Company sold 6,164,000 shares of common stock, including all additional shares available to cover over-allotments, at a price of $14.00 per share. The Company received aggregate net proceeds of approximately $77.8 million, after deducting underwriting discounts and commissions and other offering expenses payable by the Company. Upon the closing of the IPO, all outstanding shares of convertible preferred stock converted into 15,109,950 shares of common stock and the Company’s outstanding warrant to purchase preferred stock converted into a warrant to purchase 7,614 shares of common stock. The Company has determined that the receipt of the aggregate net proceeds from the IPO has alleviated the substantial doubt about the Company’s ability to continue as a going concern. The Company has incurred annual net operating losses in every year since its inception. The Company had an accumulated deficit of $91.9 million at September 30, 2018, and will require substantial additional capital to fund its operations. The Company has never generated any product revenue. There can be no assurance that the Company will be able to obtain additional debt or equity financing or generate product revenue or revenues from collaborative partners, on terms acceptable to the Company, on a timely basis or at all. The failure of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company’s business, results of operations, and financial condition.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2018
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Summary of Significant Accounting Policies The Company’s significant accounting policies are described in Note 2, “Summary of Significant Accounting Policies,” to the Consolidated Financial Statements included in the Company’s final prospectus filed with the SEC pursuant to Rule 424(b)(4) on May 24, 2018 (the “Prospectus”). There have been no material changes to the significant accounting policies previously disclosed in the Prospectus. Unaudited Interim Financial Information The consolidated financial statements of the Company included herein have been prepared, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been omitted from this report, as is permitted by such rules and regulations. Accordingly, these consolidated financial statements should be read in conjunction with the financial statements and notes thereto included in the Prospectus. The unaudited consolidated financial statements include the accounts of Scholar Rock Holding Corporation and its wholly owned subsidiaries. All intercompany transactions and balances of the subsidiaries have been eliminated in consolidation. In the opinion of management, the information furnished reflects all adjustments, all of which are of a normal and recurring nature, necessary for a fair presentation of the results for the reported interim periods. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period. Use of Estimates The preparation of financial statements in accordance with GAAP requires management to make estimates and judgments that may affect the reported amounts of assets and liabilities and related disclosures of contingent assets and liabilities at the date of the financial statements and the related reporting of revenues and expenses during the reporting period. Significant estimates of accounting reflected in these consolidated financial statements include, but are not limited to, estimates related to accrued expenses, the valuation of equity-based compensation, including incentive units, common stock, restricted common stock and stock options, and income taxes. The Company utilizes significant estimates and assumptions in determining the fair value of its equity-based compensation, including incentive units, common stock, restricted common stock and stock options that it believes to be reasonable under the circumstances. Actual results could differ from those estimates. Research and Development Expenses Research and development expenses are expensed as incurred and consist of costs incurred in performing research and development activities, including compensation related expenses for research and development personnel, preclinical and clinical activities including cost of supply, overhead expenses including facilities expenses, materials and supplies, amounts paid to consultants and outside service providers, and depreciation of equipment. Upfront license payments related to acquired technologies which have not yet reached technological feasibility and have no alternative future use are also included in research and development expense. Recently Issued Accounting Pronouncements In February 2016, the FASB issued Accounting Standards Update, or ASU, No. 2016‑02, Leases (Topic 842) , which supersedes all existing lease guidance. The new standard requires a company to recognize lease assets and liabilities for leases previously classified as operating leases. The new standard will be effective for the Company on January 1, 2019. In transition, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients primarily focused on leases that commenced before the effective date of Topic 842, including continuing to account for leases that commence before the effective date in accordance with previous guidance, unless the lease is modified. In July 2018, the FASB issued ASU 2018-11, which provides companies an additional, optional, transition method. This optional method allows companies to initially apply the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. The Company is continuing to evaluate the new lease guidance and is in the process of evaluating its existing population of contracts to ensure the identification of all contracts that meet the definition of a lease contract under the new standard is complete. As a result, the Company is currently assessing the impact that adoption of this guidance will have on its financial statements and footnote disclosures and it anticipates that adoption of this standard will result in an increase in assets and liabilities as the Company recognizes the rights and obligations related to its leases. In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting . The new standard will be effective for the Company on January 1, 2019. Early adoption is permitted. The standard expands the scope of ASC 718 to include all share-based payment arrangements related to the acquisition of goods and services from both nonemployees and employees. Under the amended guidance, equity-classified share-based payment awards issued to nonemployees will be measured at grant date fair value. Upon transition, the entity is required to remeasure these nonemployee awards at fair value as of the adoption date. The Company is currently evaluating the new guidance but does not expect that adoption of this standard will have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . The new standard will align the requirements for capitalizing implementation costs for hosting arrangements (services) with costs for internal-use software (assets). As a result, certain implementation costs incurred in hosting arrangements will be deferred and amortized. The new standard will be effective for the Company on January 1, 2020. Early adoption is permitted. The Company is currently evaluating the potential impact that adoption of this standard may have on the Company's financial position and results of operations.

Fair Value of Financial Assets

Fair Value of Financial Assets and Liabilities	9 Months Ended
	Sep. 30, 2018
Fair Value of Financial Assets and Liabilities
Fair Value of Financial Assets and Liabilities	3. Fair Value of Financial Assets and Liabilities The following tables summarize the assets and liabilities measured at fair value on a recurring basis at September 30, 2018 and December 31, 2017 (in thousands): Fair Value Measurements at September 30, 2018 Total Level 1 Level 2 Level 3 Assets: Money market funds, included in cash and cash equivalents $ 103,137 $ 103,137 $ $ Total assets $ 103,137 $ 103,137 $ — $ — Fair Value Measurements at December 31, 2017 Total Level 1 Level 2 Level 3 Assets: Money market funds, included in cash and cash equivalents $ 55,291 $ 55,291 $ — $ — Marketable securities: U.S. Treasury obligations 1,498 1,498 — — Total assets $ 56,789 $ 56,789 $ — $ — Liabilities: Warrant to purchase redeemable security $ 37 $ — $ — $ 37 Total liabilities $ 37 $ — $ — $ 37 There were no transfers between fair value measurements levels during the three or nine months ended September 30, 2018 or 2017. Cash and cash equivalents and marketable securities include investments in money market funds that invest in U.S. government securities that are valued using quoted market prices. Accordingly, money market funds and government funds are categorized as Level 1 as of September 30, 2018 and December 31, 2017. The carrying amounts reflected in the balance sheets for accounts receivable, prepaid expenses and other current assets, accounts payable, and accrued expenses approximate their fair values at September 30, 2018 and December 31, 2017, due to their short-term nature. The Company believes the terms of the loan payable reflect current market conditions for an instrument with similar terms and maturity, therefore the carrying value of the Company’s debt approximates its fair value based on Level 3 of the fair value hierarchy. Upon the completion of the IPO, the Company’s outstanding warrant to purchase preferred stock converted into a warrant to purchase common stock and the Company reclassified the fair value of the warrant to additional paid-in capital. The following table presents activity in the preferred stock warrant during the nine months ended September 30, 2018 (in thousands): Balance at December 31, 2017 $ (37) Change in fair value of warrant included in other income (expense), net (56) Reclassification to additional paid-in capital upon consummation of the IPO 93 Balance at September 30, 2018 $ — The change in fair value of the warrant included in other income (expense), net for the three and nine months ended September 30, 2018 was $0 and $(0.1) million, respectively.

Marketable Securities

Marketable Securities	9 Months Ended
	Sep. 30, 2018
Marketable Securities
Marketable Securities	4. Marketable Securities The Company did not have any available-for-sale investments as of September 30, 2018. The following table summarizes the Company’s investments as of December 31, 2017 (in thousands): Gross Amortized Unrealized Estimated Cost Gains Losses Fair Value Marketable securities available-for-sale: U.S. Treasury obligations $ 1,500 $ — $ (2) $ 1,498 Total available-for-sale securities $ 1,500 $ — $ (2) $ 1,498

Property and Equipment, Net

Property and Equipment, Net	9 Months Ended
	Sep. 30, 2018
Property and Equipment, Net
Property and Equipment, Net	5. Property and Equipment, Net As of September 30, 2018 and December 31, 2017, property and equipment, net consists of the following (in thousands): As of September 30, December 31, 2018 2017 Laboratory equipment $ 2,858 $ 2,074 Furniture & fixtures 219 151 Machinery & equipment 75 7 Leasehold improvements 1,511 1,498 Construction in progress 80 — 4,743 3,730 Less: Accumulated depreciation and amortization (2,117) (1,549) $ 2,626 $ 2,181 As of September 30, 2018 and December 31, 2017, assets under

Accrued Expenses

Accrued Expenses	9 Months Ended
	Sep. 30, 2018
Accrued Expenses
Accrued Expenses	6. Accrued Expenses As of September 30, 2018 and December 31, 2017, accrued expenses consist of the following (in thousands): As of September 30, December 31, 2018 2017 Accrued payroll and related expenses $ 1,794 $ 1,174 Accrued external research and development expense 1,163 1,225 Accrued professional and consulting expense 339 382 Accrued other 64 15 $ 3,360 $ 2,796

Common Stock and Preferred Stoc

Common Stock and Preferred Stock	9 Months Ended
	Sep. 30, 2018
Common Stock and Preferred Stock
Common Stock and Preferred Stock	7. Common Stock and Preferred Stock In connection with the consummation of the IPO, on May 29, 2018 the Company filed an amended and restated certificate of incorporation, which increased the number of shares of common stock authorized for issuance thereunder by 90,000,000 shares to 150,000,000 shares and also authorized for issuance 10,000,000 shares of Preferred Stock, par value $0.001. As of September 30, 2018, no shares of the Preferred Stock were issued or outstanding.

Equity-Based Compensation

Equity-Based Compensation	9 Months Ended
	Sep. 30, 2018
Equity-Based Compensation
Equity-Based Compensation	8. Equity-Based Compensation The Company recorded equity-based compensation expense related to all equity-based awards for employees and nonemployees, which was allocated as follows in the consolidated statements of operations (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Research and development expense $ 453 $ 145 $ 1,240 $ 370 General and administrative expense 1,033 56 1,817 319 $ 1,486 $ 201 $ 3,057 $ 689 Equity-based compensation during the three and nine months ended September 30, 2018 includes $0.3 million related to modifications of equity awards in connection with the intended retirement of the Company’s Chief Operating Officer and Head, Corporate Development, effective December 31, 2018. Restricted Stock The following table summarizes restricted common stock activity as of September 30, 2018: Weighted Average Fair Value per Share Number of Shares at Issuance Restricted common stock as of December 31, 2017 1,220,085 $ 5.77 Granted — $ Vested (353,549) $ 5.77 Forfeited (3,219) $ 5.77 Restricted common stock as of September 30, 2018 863,317 $ 5.77 As of September 30, 2018, the Company had unrecognized equity-based compensation expense of $4.0 million related to restricted stock issued to employees and directors, which is expected to be recognized over a period of 1.7 years. Stock Options The following table summarizes the Company’s stock option activity for the nine months ended September 30, 2018: Weighted Weighted Number of Average Exercise Average Remaining Aggregate Intrinsic Shares Price Contractual Term Value (in years) (in thousands) Outstanding as of December 31, 2017 — $ — — $ — Granted 1,509,705 9.64 — — Exercised (449) 5.77 — — Forfeited (8,525) 7.73 — — Outstanding as of September 30, 2018 1,500,731 $ 9.65 9.52 $ 24,157 Options exercisable as of September 30, 2018 119,066 $ 8.73 9.47 $ 2,017 Using the Black-Scholes option pricing model, the weighted average fair value of options granted to employees and directors during the nine months ended September 30, 2018 was $6.81. The following assumptions were used in determining the fair value of options granted to employees and non-employees: Nine Months Ended September 30, 2018 Employees Non-Employees Risk-free interest rate 2.76 % 3.05 % Expected dividend yield — % - % Expected term (years to liquidity) 6.12 9.39 Expected volatility 81.58 % 76.80 % As of September 30, 2018, the Company has unrecognized equity-based compensation expense related to its employee stock options of $9.0 million which the Company expects to recognize over the remaining weighted average vesting period of 3.4 years.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies
Commitments and Contingencies	9. Commitments and Contingencies The Company enters into agreements in the normal course of business with vendors for preclinical research and development studies, preclinical and clinical supply and manufacturing services, clinical trial services, professional consultants for expert advice and other vendors for other services for operating purposes. Operating Leases Facility Lease In March 2015, the Company entered into a five‑year lease for approximately 11,600 square feet of laboratory and office space at 620 Memorial Drive, Cambridge, Massachusetts, as amended in February 2016 (the ‘‘lease’’). The lease was further amended in February 2018, to add an additional 9,132 square feet (the ‘‘expansion space’’) at the current location and to extend the lease term (the ‘‘amended lease’’). The amended lease expires in July 2023. Rent for the facility lease, including the expansion space, increases from $1.4 million a year to $1.7 million a year over the term of the lease. Legal Proceedings The Company is not currently a party to any material legal proceedings.

Loan Payable

Loan Payable	9 Months Ended
	Sep. 30, 2018
Loan Payable
Loan Payable	10. Loan Payable In August 2015, the Company entered into a Loan and Security Agreement with Silicon Valley Bank (‘‘SVB’’), which provided the Company an equipment line of credit of up to $2.0 million to finance the purchase of eligible equipment. The loan balance at September 30, 2018 and December 31, 2017 was $0.6 million and $1.0 million, respectively.

Option and License Agreement

Option and License Agreement	9 Months Ended
	Sep. 30, 2018
Option and License Agreement
Option and License Agreement	11. Option and License Agreement Overview On December 17, 2013, the Company entered into an option and license agreement with Janssen. Janssen is obligated to pay the Company certain development milestones totaling up to $25.0 million and regulatory milestones totaling up to $97.0 million for the pharmacological profile licensed by Janssen during the development period and through successful regulatory approval, as further described in the option and license agreement. Development milestones are triggered upon the achievement of specified development criteria or dosing of a specified number of patients in phases of clinical trials. Regulatory milestones are triggered upon approval to market a product candidate by the U.S. Food and Drug Administration (‘‘FDA’’) or other global regulatory authorities. Additionally, commercial milestone payments totaling up to $130.0 million for the pharmacological profile are eligible to be earned as certain sales thresholds are achieved by Janssen and royalties are also required to be paid by Janssen to the Company based on annual net sales thresholds, based on Janssen’s sales of a product derived from the collaboration molecule(s). The next potential milestone the Company may be entitled to receive under the agreement is a milestone payment of $2.0 million upon achievement of a development milestone. The Company did not recognize any revenue from its option and license agreement with Janssen in the three or nine-month periods ended September 30, 2018 or September 30, 2017, respectively.

Net Loss per Share

Net Loss per Share	9 Months Ended
	Sep. 30, 2018
Net Loss per Share
Net Loss per Share	12. Net Loss per Share Prior to the Reorganization, the Company calculated basic net loss per unit by dividing net loss by the weighted average number of common units outstanding. Subsequent to the Reorganization, the Company calculates basic net loss per share by dividing net loss by the weighted average number of common shares outstanding, excluding restricted common stock. The Company calculates diluted net loss per unit and diluted net loss per share by dividing net loss by the weighted average number of common units outstanding or weighted average number of common shares outstanding, as applicable, after giving consideration to the dilutive effect of convertible preferred units, convertible preferred stock, incentive units, restricted common stock, warrants and stock options that are outstanding during the period. The Company has generated a net loss in all periods presented, so the basic and diluted net loss per unit and net loss per share are the same, as the inclusion of the potentially dilutive securities would be anti-dilutive. The significant increase in shares outstanding in the second quarter of 2018 is expected to impact the year-over-year comparability of the Company’s net loss per share calculations for the next nine months. The following table sets forth the outstanding common unit or common stock equivalents, presented based on amounts outstanding at each period end, that have been excluded from the calculation of diluted net loss per unit or share for the periods indicated because their inclusion would have been anti-dilutive (in common unit or common stock equivalent shares, as applicable): Three and Nine Months Ended September 30, 2018 2017 Convertible preferred units — 10,536,765 Incentive units — 2,292,164 Restricted common stock 863,317 — Warrant 7,614 7,614 Stock options 1,500,731 — 2,371,662 12,836,543

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2018
Related Party Transactions
Related Party Transactions	13. Related Party Transactions Licensing Agreement Pursuant to a license agreement with Children’s Medical Center Corporation (‘‘CMCC’’), a holder of shares of the Company’s common stock, the Company incurred $10,000 for a CMCC annual license maintenance fee in 2017, which was paid in 2018. The Company did not make any payments for the CMCC license maintenance fees during the three and nine months ended September 30, 2017, respectively. The Company paid $0 and $10,000 during the three and nine months ended September 30, 2018, respectively. The obligation continues until the agreement is terminated. The Company will also be responsible for up to $1.3 million of development milestone payments through the first regulatory approval of a licensed product, tiered royalty payments of low single-digit percentages on net sales of licensed products in the event that the Company realizes sales from products covered by the license agreement, which are products developed using the Company’s proprietary platform that are covered by a valid claim contained in any patent under the license agreement, and between 10% to 20% of non-royalty income attributable to a sublicense of the CMCC rights. The Company recorded such payments as research and development expense in the statements of operations. There was $10,000 and $0 due to CMCC under this license agreement at December 31, 2017 and September 30, 2018. Consulting Agreements The Company entered into consulting agreements on October 10, 2012 with its two scientific co-founders to provide services related to the advancement of the research and development platform of the company. The consulting arrangements are on a fixed-fee basis, paid quarterly. The initial contract terms were four years and terminated on October 10, 2016. The contracts were extended for an additional four year period. The Company incurred $40,000 and $120,000 for the three and nine months ended September 30, 2018 and September 30, 2017, respectively. There are no amounts due under these consulting agreements at December 31, 2017 or September 30, 2018.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2018
Summary of Significant Accounting Policies
Unaudited Interim Financial Information	Unaudited Interim Financial Information The consolidated financial statements of the Company included herein have been prepared, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been omitted from this report, as is permitted by such rules and regulations. Accordingly, these consolidated financial statements should be read in conjunction with the financial statements and notes thereto included in the Prospectus. The unaudited consolidated financial statements include the accounts of Scholar Rock Holding Corporation and its wholly owned subsidiaries. All intercompany transactions and balances of the subsidiaries have been eliminated in consolidation. In the opinion of management, the information furnished reflects all adjustments, all of which are of a normal and recurring nature, necessary for a fair presentation of the results for the reported interim periods. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period.
Use of Estimates	Use of Estimates The preparation of financial statements in accordance with GAAP requires management to make estimates and judgments that may affect the reported amounts of assets and liabilities and related disclosures of contingent assets and liabilities at the date of the financial statements and the related reporting of revenues and expenses during the reporting period. Significant estimates of accounting reflected in these consolidated financial statements include, but are not limited to, estimates related to accrued expenses, the valuation of equity-based compensation, including incentive units, common stock, restricted common stock and stock options, and income taxes. The Company utilizes significant estimates and assumptions in determining the fair value of its equity-based compensation, including incentive units, common stock, restricted common stock and stock options that it believes to be reasonable under the circumstances. Actual results could differ from those estimates.
Research and Development Expenses	Research and Development Expenses Research and development expenses are expensed as incurred and consist of costs incurred in performing research and development activities, including compensation related expenses for research and development personnel, preclinical and clinical activities including cost of supply, overhead expenses including facilities expenses, materials and supplies, amounts paid to consultants and outside service providers, and depreciation of equipment. Upfront license payments related to acquired technologies which have not yet reached technological feasibility and have no alternative future use are also included in research and development expense.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In February 2016, the FASB issued Accounting Standards Update, or ASU, No. 2016‑02, Leases (Topic 842) , which supersedes all existing lease guidance. The new standard requires a company to recognize lease assets and liabilities for leases previously classified as operating leases. The new standard will be effective for the Company on January 1, 2019. In transition, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients primarily focused on leases that commenced before the effective date of Topic 842, including continuing to account for leases that commence before the effective date in accordance with previous guidance, unless the lease is modified. In July 2018, the FASB issued ASU 2018-11, which provides companies an additional, optional, transition method. This optional method allows companies to initially apply the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. The Company is continuing to evaluate the new lease guidance and is in the process of evaluating its existing population of contracts to ensure the identification of all contracts that meet the definition of a lease contract under the new standard is complete. As a result, the Company is currently assessing the impact that adoption of this guidance will have on its financial statements and footnote disclosures and it anticipates that adoption of this standard will result in an increase in assets and liabilities as the Company recognizes the rights and obligations related to its leases. In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting . The new standard will be effective for the Company on January 1, 2019. Early adoption is permitted. The standard expands the scope of ASC 718 to include all share-based payment arrangements related to the acquisition of goods and services from both nonemployees and employees. Under the amended guidance, equity-classified share-based payment awards issued to nonemployees will be measured at grant date fair value. Upon transition, the entity is required to remeasure these nonemployee awards at fair value as of the adoption date. The Company is currently evaluating the new guidance but does not expect that adoption of this standard will have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . The new standard will align the requirements for capitalizing implementation costs for hosting arrangements (services) with costs for internal-use software (assets). As a result, certain implementation costs incurred in hosting arrangements will be deferred and amortized. The new standard will be effective for the Company on January 1, 2020. Early adoption is permitted. The Company is currently evaluating the potential impact that adoption of this standard may have on the Company's financial position and results of operations.

Fair Value of Financial Asset_2

Fair Value of Financial Assets and Liabilities - (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value of Financial Assets and Liabilities
Schedule of summary of the assets and liabilities measured at fair value on a recurring basis	The following tables summarize the assets and liabilities measured at fair value on a recurring basis at September 30, 2018 and December 31, 2017 (in thousands): Fair Value Measurements at September 30, 2018 Total Level 1 Level 2 Level 3 Assets: Money market funds, included in cash and cash equivalents $ 103,137 $ 103,137 $ $ Total assets $ 103,137 $ 103,137 $ — $ — Fair Value Measurements at December 31, 2017 Total Level 1 Level 2 Level 3 Assets: Money market funds, included in cash and cash equivalents $ 55,291 $ 55,291 $ — $ — Marketable securities: U.S. Treasury obligations 1,498 1,498 — — Total assets $ 56,789 $ 56,789 $ — $ — Liabilities: Warrant to purchase redeemable security $ 37 $ — $ — $ 37 Total liabilities $ 37 $ — $ — $ 37
Schedule of changes in the fair value of the warrant, which represented a recurring measurement classified within Level 3 of the fair value hierarchy,	The following table presents activity in the preferred stock warrant during the nine months ended September 30, 2018 (in thousands): Balance at December 31, 2017 $ (37) Change in fair value of warrant included in other income (expense), net (56) Reclassification to additional paid-in capital upon consummation of the IPO 93 Balance at September 30, 2018 $ —

Marketable Securities (Tables)

Marketable Securities (Tables)	9 Months Ended
	Sep. 30, 2018
Marketable Securities
Summary of investments	The following table summarizes the Company’s investments as of December 31, 2017 (in thousands): Gross Amortized Unrealized Estimated Cost Gains Losses Fair Value Marketable securities available-for-sale: U.S. Treasury obligations $ 1,500 $ — $ (2) $ 1,498 Total available-for-sale securities $ 1,500 $ — $ (2) $ 1,498

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	9 Months Ended
	Sep. 30, 2018
Property and Equipment, Net
Summary of property and equipment	As of September 30, 2018 and December 31, 2017, property and equipment, net consists of the following (in thousands): As of September 30, December 31, 2018 2017 Laboratory equipment $ 2,858 $ 2,074 Furniture & fixtures 219 151 Machinery & equipment 75 7 Leasehold improvements 1,511 1,498 Construction in progress 80 — 4,743 3,730 Less: Accumulated depreciation and amortization (2,117) (1,549) $ 2,626 $ 2,181

Accrued Expenses (Tables)

Accrued Expenses (Tables)	9 Months Ended
	Sep. 30, 2018
Accrued Expenses
Summary of accrued expenses	As of September 30, 2018 and December 31, 2017, accrued expenses consist of the following (in thousands): As of September 30, December 31, 2018 2017 Accrued payroll and related expenses $ 1,794 $ 1,174 Accrued external research and development expense 1,163 1,225 Accrued professional and consulting expense 339 382 Accrued other 64 15 $ 3,360 $ 2,796

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2018
Equity-Based Compensation
Schedule of allocation of equity-based compensation in the consolidated statements of operations	The Company recorded equity-based compensation expense related to all equity-based awards for employees and nonemployees, which was allocated as follows in the consolidated statements of operations (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Research and development expense $ 453 $ 145 $ 1,240 $ 370 General and administrative expense 1,033 56 1,817 319 $ 1,486 $ 201 $ 3,057 $ 689
Summary of restricted common stock activity	Weighted Average Fair Value per Share Number of Shares at Issuance Restricted common stock as of December 31, 2017 1,220,085 $ 5.77 Granted — $ Vested (353,549) $ 5.77 Forfeited (3,219) $ 5.77 Restricted common stock as of September 30, 2018 863,317 $ 5.77
Summary of stock option activity	Weighted Weighted Number of Average Exercise Average Remaining Aggregate Intrinsic Shares Price Contractual Term Value (in years) (in thousands) Outstanding as of December 31, 2017 — $ — — $ — Granted 1,509,705 9.64 — — Exercised (449) 5.77 — — Forfeited (8,525) 7.73 — — Outstanding as of September 30, 2018 1,500,731 $ 9.65 9.52 $ 24,157 Options exercisable as of September 30, 2018 119,066 $ 8.73 9.47 $ 2,017
Schedule of fair value assumptions	Nine Months Ended September 30, 2018 Employees Non-Employees Risk-free interest rate 2.76 % 3.05 % Expected dividend yield — % - % Expected term (years to liquidity) 6.12 9.39 Expected volatility 81.58 % 76.80 %

Net Loss per Share (Tables)

Net Loss per Share (Tables)	9 Months Ended
	Sep. 30, 2018
Net Loss per Share
Summary of anti-dilutive securities	Three and Nine Months Ended September 30, 2018 2017 Convertible preferred units — 10,536,765 Incentive units — 2,292,164 Restricted common stock 863,317 — Warrant 7,614 7,614 Stock options 1,500,731 — 2,371,662 12,836,543

Nature of the Business (Details

Nature of the Business (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Nature of the Business
Shares sold	$ 6,164,000
Sales price (in dollars per share)	$ 14	$ 14
Net proceeds	$ 77,800,000
Convertible preferred stock converted into shares	15,109,950
Shares that warrant can purchase	7,614	7,614
Accumulated deficit	$ (91,886,000)	$ (91,886,000)	$ (57,525,000)
Revenue		$ 0

Fair Value of Financial Asset_3

Fair Value of Financial Assets and Liabilities - (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Assets:
Money market funds, included in cash and cash equivalents	$ 103,137	$ 55,291
Marketable securities:
US Treasury obligation		1,498
Total assets	103,137	56,789
Liabilities:
Warrant to purchase redeemable security		37
Total liabilities		37
Level 1
Assets:
Money market funds, included in cash and cash equivalents	103,137	55,291
Marketable securities:
US Treasury obligation		1,498
Total assets	$ 103,137	56,789
Level 3
Liabilities:
Warrant to purchase redeemable security		37
Total liabilities		$ 37

Fair Value of Financial Asset_4

Fair Value of Financial Assets and Liabilities - Roll forward (Details) - Recurring - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Changes in the fair value of the warrant
Balance, beginning		$ (37)
Change in fair value of warrant included in other income (expense), net	$ 0	(56)
Reclassification to additional paid-in capital upon consummation of the IPO		$ 93

Marketable Securities (Details)

Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Marketable securities available-for-sale
Amortization Cost	$ 0	$ 1,500
Gross Unrealized Losses		(2)
Estimated Fair Value		1,498
U.S. Treasury obligations
Marketable securities available-for-sale
Amortization Cost		1,500
Gross Unrealized Losses		(2)
Estimated Fair Value		$ 1,498

Property and Equipment, Net (De

Property and Equipment, Net (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Property and Equipment, Net
Property and Equipment, gross	$ 4,743,000	$ 3,730,000
Less: Accumulated depreciation and amortization	(2,117,000)	(1,549,000)
Total property and equipment, net	2,626,000	2,181,000
Capital lease cost basis	44,000	0
Laboratory equipment
Property and Equipment, Net
Property and Equipment, gross	2,858,000	2,074,000
Furniture & fixtures
Property and Equipment, Net
Property and Equipment, gross	219,000	151,000
Machinery & equipment
Property and Equipment, Net
Property and Equipment, gross	75,000	7,000
Leasehold improvements
Property and Equipment, Net
Property and Equipment, gross	1,511,000	$ 1,498,000
Construction in progress
Property and Equipment, Net
Property and Equipment, gross	$ 80,000

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accrued Expenses
Accrued payroll and related expenses	$ 1,794	$ 1,174
Accrued external research and development expense	1,163	1,225
Accrued professional and consulting expense	339	382
Accrued other	64	15
Accrued expenses	$ 3,360	$ 2,796

Common Stock and Preferred St_2

Common Stock and Preferred Stock (Details) - $ / shares	3 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Common Stock and Preferred Stock
Common stock, increase in number of shares authorized	90,000,000
Common stock, shares authorized	150,000,000	60,000,000
Preferred stock, shares authorized	10,000,000	0
Preferred stock, par value	$ 0.001
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0

Equity-Based Compensation - Exp

Equity-Based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity-based compensation
Equity-based compensation expense	$ 1,486	$ 201	$ 3,057	$ 689
Equity-based compensation expense related to modifications of equity awards	300		300
Research and development expense
Equity-based compensation
Equity-based compensation expense	453	145	1,240	370
General and administrative expense
Equity-based compensation
Equity-based compensation expense	$ 1,033	$ 56	$ 1,817	$ 319

Equity-Based Compensation - Res

Equity-Based Compensation - Restricted stock (Details) - Restricted common stock $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)$ / sharesshares
Number of Shares
Restricted common stock, beginning (in shares) | shares	1,220,085
Vested (in shares) | shares	(353,549)
Forfeited (in shares) | shares	(3,219)
Restricted common stock, ending (in shares) | shares	863,317
Weighted Average Fair Value per Share at Issuance
Restricted common stock, beginning (in dollars per share) | $ / shares	$ 5.77
Vested (in dollars per share) | $ / shares	5.77
Forfeited (in dollars per share) | $ / shares	5.77
Restricted common stock, ending (in dollars per share) | $ / shares	$ 5.77
Unrecognized equity based compensation expense | $	$ 4
Period for recognition	1 year 8 months 12 days

Equity-Based Compensation - Sto

Equity-Based Compensation - Stock options (Details) - Stock options $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)$ / sharesshares
Number of Shares
Granted (in shares) | shares	1,509,705
Exercised (in shares) | shares	(449)
Forfeited (in shares) | shares	(8,525)
Outstanding, end (in shares) | shares	1,500,731
Outstanding exercisable, end (in shares) | shares	119,066
Weighted Average Exercise Price
Granted (in dollars per share)	$ 9.64
Exercised (in dollars per share)	5.77
Forfeited (in dollars per share)	7.73
Outstanding, end (in dollars per share)	9.65
Outstanding exercisable, end (in dollars per share)	$ 8.73
Stock options
Weighted average remaining contractual term	9 years 6 months 7 days
Aggregate intrinsic value | $	$ 24,157
Weighted average remaining contractual term, exercisable	9 years 5 months 19 days
Aggregate intrinsic value, exercisable | $	$ 2,017
Weighted average fair value of options granted	$ 6.81

Equity-Based Compensation - Ass

Equity-Based Compensation - Assumptions (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Employees
Assumptions used in determining the fair value of options
Risk-free interest rate	2.76%
Expected term (years to liquidity)	6 years 1 month 13 days
Expected volatility	81.58%
Unrecognized stock based compensation expense	$ 9
Period for recognition	3 years 4 months 24 days
Non-Employees
Assumptions used in determining the fair value of options
Risk-free interest rate	3.05%
Expected term (years to liquidity)	9 years 4 months 21 days
Expected volatility	76.80%

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	1 Months Ended
	Feb. 28, 2018USD ($)ft²	Mar. 31, 2015ft²
Lease
Term of lease		5 years
Area of lease space | ft²		11,600
Area of expansion space | ft²	9,132
Minimum
Lease
Lease rent | $	$ 1.4
Maximum
Lease
Lease rent | $	$ 1.7

Loan Payable (Details)

Loan Payable (Details) - SVB - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017	Aug. 31, 2015
Loan Payable
Line of credit maximum			$ 2
Amount borrowed	$ 0.6	$ 1

Option and License Agreement (D

Option and License Agreement (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 17, 2013
Option and License Agreement
Revenue received	$ 0	$ 0	$ 0	$ 0
Development milestones
Option and License Agreement
Potential milestone payments	$ 2		$ 2		$ 25
Regulatory milestones
Option and License Agreement
Potential milestone payments					97
Sales milestones
Option and License Agreement
Potential milestone payments					$ 130

Net Loss per Share (Details)

Net Loss per Share (Details) - shares	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Antidilutive securities
Anti-dilutive securities excluded from the calculation of net loss per share	2,371,662	12,836,543
Convertible preferred units
Antidilutive securities
Anti-dilutive securities excluded from the calculation of net loss per share		10,536,765
Incentive units
Antidilutive securities
Anti-dilutive securities excluded from the calculation of net loss per share		2,292,164
Restricted common stock
Antidilutive securities
Anti-dilutive securities excluded from the calculation of net loss per share	863,317
Warrant
Antidilutive securities
Anti-dilutive securities excluded from the calculation of net loss per share	7,614	7,614
Stock options
Antidilutive securities
Anti-dilutive securities excluded from the calculation of net loss per share	1,500,731

Related Party Transactions (Det

Related Party Transactions (Details)	Oct. 10, 2016	Oct. 10, 2012item	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)
CMCC
Related Party Transactions
Related party transaction amount			$ 0		$ 10,000		$ 10,000
Potential milestone payable			1,300,000		1,300,000
Amounts due			0		$ 0		10,000
CMCC | Minimum
Related Party Transactions
Non-royalty income attributable to sublicense (as a percent)					10.00%
CMCC | Maximum
Related Party Transactions
Non-royalty income attributable to sublicense (as a percent)					20.00%
Co-founders
Related Party Transactions
Related party transaction amount			40,000	$ 40,000	$ 120,000	$ 120,000
Amounts due			$ 0		$ 0		$ 0
Number of scientific co-founders | item		2
Term of agreement	4 years	4 years