Document and Entity Information
Document and Entity Information - shares | 6 Months Ended | |
Jun. 30, 2019 | Jul. 30, 2019 | |
Document And Entity Information [Abstract] | ||
Document Type | 10-Q | |
Amendment Flag | false | |
Document Period End Date | Jun. 30, 2019 | |
Document Fiscal Year Focus | 2019 | |
Document Fiscal Period Focus | Q2 | |
Trading Symbol | EIDX | |
Entity Registrant Name | Eidos Therapeutics, Inc. | |
Entity Central Index Key | 0001731831 | |
Current Fiscal Year End Date | --12-31 | |
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 | 36,884,175 | |
Entity Current Reporting Status | Yes | |
Entity Shell Company | false | |
Entity File Number | 001-38533 | |
Entity Tax Identification Number | 463733671 | |
Entity Address, Address Line One | 101 Montgomery Street | |
Entity Address, Address Line Two | Suite 2550 | |
Entity Address, City or Town | San Francisco | |
Entity Address, State or Province | CA | |
Entity Address, Postal Zip Code | 94104 | |
City Area Code | 415 | |
Local Phone Number | 887-1471 |
Condensed Balance Sheets (Unaud
Condensed Balance Sheets (Unaudited) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Current assets: | ||
Cash and cash equivalents | $ 131,400 | $ 157,147 |
Related party receivable | 197 | 34 |
Prepaid expenses and other current assets | 3,928 | 1,789 |
Total current assets | 135,525 | 158,970 |
Property and equipment, net | 204 | 209 |
Operating lease, right of use asset | 988 | |
Other assets | 2,564 | 933 |
Total assets | 139,281 | 160,112 |
Current liabilities: | ||
Accounts payable | 1,842 | 1,956 |
Related party payable | 344 | 256 |
Lease liabilities | 276 | |
Accrued expenses and other current liabilities | 4,027 | 2,577 |
Total current liabilities | 6,489 | 4,789 |
Other liabilities | 164 | 316 |
Lease liabilities, non-current | 782 | |
Total liabilities | 7,435 | 5,105 |
Commitments and contingencies | ||
Stockholders’ equity: | ||
Preferred stock, $0.001 par value, 5,000,000 shares authorized; no shares issued and outstanding; | ||
Common stock, $0.001 par value; 150,000,000 shares authorized as of June 30, 2019 and December 31, 2018, respectively; 36,871,175 and 36,760,536 shares issued and outstanding as of June 30, 2019 and December 31, 2018, respectively; | 37 | 37 |
Additional paid-in-capital | 222,865 | 220,240 |
Accumulated deficit | (91,056) | (65,270) |
Total stockholders’ equity | 131,846 | 155,007 |
Total liabilities, redeemable convertible preferred stock and stockholders’ equity | $ 139,281 | $ 160,112 |
Condensed Balance Sheets (Una_2
Condensed Balance Sheets (Unaudited) (Parenthetical) - $ / shares | Jun. 30, 2019 | Dec. 31, 2018 |
Statement Of Financial Position [Abstract] | ||
Preferred stock, par value | $ 0.001 | $ 0.001 |
Preferred stock, shares authorized | 5,000,000 | 5,000,000 |
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 | 150,000,000 |
Common stock, shares issued | 36,871,175 | 36,760,536 |
Common stock, shares outstanding | 36,871,175 | 36,760,536 |
Statements of Operations and Co
Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Operating expenses: | ||||
Research and development (includes related party expense (benefit) of ($30) and $10 for the three months ended June 30, 2019 and 2018, and $64 and $26 for the six months ended June 30, 2019 and 2018 , respectively) | $ 12,497 | $ 6,195 | $ 21,046 | $ 11,847 |
General and administrative (includes related party expense of $74 and $428 for the three months ended June 30, 2019 and 2018, and $153 and $752 for the six months ended June 30, 2019 and 2018, respectively) | 2,297 | 1,894 | 6,332 | 4,239 |
Total operating expenses | 14,794 | 8,089 | 27,378 | 16,086 |
Loss from operations | (14,794) | (8,089) | (27,378) | (16,086) |
Other income (expense), net | 741 | (3,292) | 1,592 | (4,171) |
Net and comprehensive loss | (14,053) | (11,381) | (25,786) | (20,257) |
Deemed dividend related to redemption feature embedded in Convertible Promissory Notes payable to stockholders | (6,523) | |||
Gain on extinguishment of Convertible Promissory Notes payable to stockholders | 7,436 | |||
Net loss attributable to common stockholders | $ (14,053) | $ (11,381) | $ (25,786) | $ (19,344) |
Net loss per share attributable to common stockholders, basic and diluted | $ (0.39) | $ (1.40) | $ (0.71) | $ (3.06) |
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted | 36,309,740 | 8,109,653 | 36,242,814 | 6,328,827 |
Statements of Operations and _2
Statements of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Income Statement [Abstract] | ||||
Research and development expense (benefit) included from related party | $ 30 | $ 10 | $ 64 | $ 26 |
General and administrative expense included from related party | $ 74 | $ 428 | $ 153 | $ 752 |
Condensed Statements of Redeema
Condensed Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) | Total | Series B Redeemable Convertible Preferred Stock | Common Stock | Additional Paid in Capital | Accumulated Deficit |
Balance at Dec. 31, 2017 | $ (13,196,000) | $ 4,000 | $ 1,332,000 | $ (14,532,000) | |
Redeemable convertible preferred stock, Balance, Shares at Dec. 31, 2017 | 12,856,325 | ||||
Redeemable convertible preferred stock, Balance at Dec. 31, 2017 | $ 17,028,000 | ||||
Balance, Shares at Dec. 31, 2017 | 5,137,771 | ||||
Issuance of Series B redeemable convertible preferred stock upon conversion of redeemable convertible promissory notes payable to stockholders | $ 14,354,000 | ||||
Issuance of Series B redeemable convertible preferred stock upon conversion of redeemable convertible promissory notes payable to stockholders, Shares | 1,324,823 | ||||
Recognition of beneficial conversion feature related to convertible promissory notes payable to stockholders | 9,122,000 | 9,122,000 | |||
Deemed dividend related to redemption feature embedded in Convertible Promissory Notes payable to stockholders | (6,523,000) | (6,523,000) | |||
Issuance of common stock to Stanford University | 7,000 | 7,000 | |||
Issuance of common stock to Stanford University, Shares | 45,889 | ||||
Issuance of common stock upon exercise of stock options and restricted stock, Shares | 149,350 | ||||
Issuance of Series B redeemable convertible preferred stock, net of issuance costs of $125 and fair value of redeemable convertible preferred stock tranche liability of $64 | $ 15,811,000 | ||||
Issuance of redeemable convertible preferred stock, net of issuance costs and tranche liability, Shares | 1,476,715 | ||||
Reacquisition of beneficial conversion feature related to Convertible Promissory Notes payable to stockholders | (14,354,000) | (4,341,000) | (10,013,000) | ||
Gain on extinguishment of Convertible Promissory Notes payable to stockholders | 7,436,000 | 7,436,000 | |||
Vesting of restricted stock and early exercised options | 18,000 | 18,000 | |||
Stock-based compensation expense | 385,000 | 385,000 | |||
Net loss and comprehensive loss | (8,876,000) | (8,876,000) | |||
Balance at Mar. 31, 2018 | (25,981,000) | $ 4,000 | 7,436,000 | (33,421,000) | |
Redeemable convertible preferred stock, Balance, Shares at Mar. 31, 2018 | 15,657,863 | ||||
Redeemable convertible preferred stock, Balance at Mar. 31, 2018 | $ 47,193,000 | ||||
Balance, Shares at Mar. 31, 2018 | 5,333,010 | ||||
Balance at Dec. 31, 2017 | (13,196,000) | $ 4,000 | 1,332,000 | (14,532,000) | |
Redeemable convertible preferred stock, Balance, Shares at Dec. 31, 2017 | 12,856,325 | ||||
Redeemable convertible preferred stock, Balance at Dec. 31, 2017 | $ 17,028,000 | ||||
Balance, Shares at Dec. 31, 2017 | 5,137,771 | ||||
Deemed dividend related to redemption feature embedded in Convertible Promissory Notes payable to stockholders | (6,523,000) | ||||
Gain on extinguishment of Convertible Promissory Notes payable to stockholders | 7,436,000 | ||||
Balance at Jun. 30, 2018 | 173,644,000 | $ 37,000 | 218,409,000 | (44,802,000) | |
Balance, Shares at Jun. 30, 2018 | 36,752,027 | ||||
Balance at Mar. 31, 2018 | (25,981,000) | $ 4,000 | 7,436,000 | (33,421,000) | |
Redeemable convertible preferred stock, Balance, Shares at Mar. 31, 2018 | 15,657,863 | ||||
Redeemable convertible preferred stock, Balance at Mar. 31, 2018 | $ 47,193,000 | ||||
Balance, Shares at Mar. 31, 2018 | 5,333,010 | ||||
Issuance of redeemable convertible preferred stock, net of issuance costs | $ 48,000,000 | ||||
Issuance of redeemable convertible preferred stock, net of issuance, Shares | 4,430,162 | ||||
Settlement of fair value of redeemable convertible preferred stock tranche liability upon exercise of put option to stockholders into Series B redeemable convertible preferred stock | $ 694,000 | ||||
Net exercise of redeemable convertible preferred stock warrant liability | 3,506,000 | $ 206,247,000 | 3,506,000 | ||
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering | 95,887,000 | $ 25,000 | 95,862,000 | ||
Conversion of redeemable convertible preferred stock to common stock at closing, Shares | (20,088,025) | ||||
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering | $ (95,887,000) | ||||
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering, Shares | 24,025,270 | ||||
Issuance of common stock upon initial public offering, net of issuance costs | 110,970,000 | $ 8,000 | 110,962,000 | ||
Issuance of common stock upon initial public offering, net of issuance costs, Shares | 7,187,500 | ||||
Vesting of restricted stock and early exercised options | 22,000 | 22,000 | |||
Stock-based compensation expense | 621,000 | 621,000 | |||
Net loss and comprehensive loss | (11,381,000) | (11,381,000) | |||
Balance at Jun. 30, 2018 | 173,644,000 | $ 37,000 | 218,409,000 | (44,802,000) | |
Balance, Shares at Jun. 30, 2018 | 36,752,027 | ||||
Balance at Dec. 31, 2018 | $ 155,007,000 | $ 37,000 | 220,240,000 | (65,270,000) | |
Redeemable convertible preferred stock, Balance, Shares at Dec. 31, 2018 | 0 | ||||
Balance, Shares at Dec. 31, 2018 | 36,760,536 | ||||
Issuance of common stock upon exercise of stock options and restricted stock | $ 25,000 | 25,000 | |||
Issuance of common stock upon exercise of stock options and restricted stock, Shares | 50,533 | ||||
Vesting of restricted stock and early exercised options | 38,000 | 38,000 | |||
Stock-based compensation expense | 964,000 | 964,000 | |||
Net loss and comprehensive loss | (11,733,000) | (11,733,000) | |||
Balance at Mar. 31, 2019 | 144,301,000 | $ 37,000 | 221,267,000 | (77,003,000) | |
Balance, Shares at Mar. 31, 2019 | 36,811,069 | ||||
Balance at Dec. 31, 2018 | $ 155,007,000 | $ 37,000 | 220,240,000 | (65,270,000) | |
Redeemable convertible preferred stock, Balance, Shares at Dec. 31, 2018 | 0 | ||||
Balance, Shares at Dec. 31, 2018 | 36,760,536 | ||||
Issuance of common stock upon exercise of stock options and restricted stock, Shares | 85,013 | ||||
Balance at Jun. 30, 2019 | $ 131,846,000 | $ 37,000 | 222,865,000 | (91,056,000) | |
Redeemable convertible preferred stock, Balance, Shares at Jun. 30, 2019 | 0 | ||||
Balance, Shares at Jun. 30, 2019 | 36,871,175 | ||||
Balance at Mar. 31, 2019 | $ 144,301,000 | $ 37,000 | 221,267,000 | (77,003,000) | |
Balance, Shares at Mar. 31, 2019 | 36,811,069 | ||||
Issuance of common stock upon exercise of stock options and restricted stock | 87,000 | 87,000 | |||
Issuance of common stock upon exercise of stock options and restricted stock, Shares | 34,480 | ||||
Issuance of common stock under employee stock plans | 308,000 | 308,000 | |||
Issuance of common stock under employee stock plans, Shares | 25,626 | ||||
Vesting of restricted stock and early exercised options | 37,000 | 37,000 | |||
Stock-based compensation expense | 1,166,000 | 1,166,000 | |||
Net loss and comprehensive loss | (14,053,000) | (14,053,000) | |||
Balance at Jun. 30, 2019 | $ 131,846,000 | $ 37,000 | $ 222,865,000 | $ (91,056,000) | |
Redeemable convertible preferred stock, Balance, Shares at Jun. 30, 2019 | 0 | ||||
Balance, Shares at Jun. 30, 2019 | 36,871,175 |
Condensed Statements of Redee_2
Condensed Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - Series B Redeemable Convertible Preferred Stock - USD ($) $ in Thousands | 3 Months Ended | |
Jun. 30, 2018 | Mar. 31, 2018 | |
Issuance costs | $ 125 | |
Redeemable convertible preferred stock tranche liability | $ 64 | |
Issuance costs for additional redeemable convertible preferred stock | $ 0 |
Condensed Statements of Cash Fl
Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands | 6 Months Ended | |
Jun. 30, 2019 | Jun. 30, 2018 | |
Cash Flows From Operating Activities: | ||
Net loss | $ (25,786) | $ (20,257) |
Adjustments to reconcile net loss to net cash used in operating activities: | ||
Depreciation and amortization | 33 | 24 |
Stock-based compensation expense | 2,130 | 1,007 |
Accrued interest on Convertible Promissory Notes payable | 48 | |
Change in fair value of derivative liability | (100) | |
Change in fair value of redeemable convertible preferred stock tranche liabilities | 630 | |
Change in fair value of redeemable convertible preferred stock warrant liability | 2,628 | |
Amortization of debt discount on Convertible Promissory Notes payable | 963 | |
Loss on disposal of property and equipment | 7 | |
Changes in assets and liabilities: | ||
Related party receivable | (163) | 46 |
Prepaid expenses and other current assets | (2,139) | (1,761) |
Other assets | (2,619) | 12 |
Accounts payable | (114) | 1,157 |
Accrued expenses and other liabilities | 2,431 | 646 |
Related party payable | 88 | 159 |
Net cash used in operating activities | (26,132) | (14,798) |
Cash Flows From Investing Activities: | ||
Purchase of property and equipment | (35) | (129) |
Net cash used in investing activities | (35) | (129) |
Cash Flows From Financing Activities: | ||
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs | 63,875 | |
Proceeds from issuance of Convertible Promissory Notes payable | 10,000 | |
Proceeds from issuance of common stock under employee stock plan | 308 | |
Proceeds from issuance of common stock upon exercise of stock options and restricted stock | 112 | 89 |
Proceeds from issuance of common stock in initial public offering, net of issuance costs | 112,155 | |
Net cash provided by financing activities | 420 | 186,119 |
Net (decrease) increase in cash and cash equivalents | (25,747) | 171,192 |
Cash and cash equivalents, beginning of period | 157,147 | 5,497 |
Cash and cash equivalents, end of period | 131,400 | 176,689 |
Supplemental disclosure of non-cash activities: | ||
Settlement of redeemable convertible preferred stock tranche liability through issuance of preferred stock | 694 | |
Lease liability arising from the right of use asset | 1,058 | |
Vesting of restricted stock and early exercised options | $ 75 | 34 |
Offering costs in accounts payable and accrued liabilities | 1,187 | |
Conversion of Convertible Promissory Notes payable and accrued interest into redeemable convertible preferred stock | 14,354 | |
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering | 95,887 | |
Reclassification of redeemable convertible preferred stock warrant liability to common stock at closing of initial public offering | $ 3,506 |
Organization and Description of
Organization and Description of Business | 6 Months Ended |
Jun. 30, 2019 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Organization and Description of Business | Note 1. Organization and description of business Eidos Therapeutics, Inc., or the Company, was incorporated as an S corporation in the state of Delaware on August 6, 2013. The Company is headquartered in San Francisco, California and it operates as one operating segment. Stock split In June 2018, the Company’s board of directors approved an amendment to the Company’s amended and restated certificate of incorporation to effect a stock-split of the Company’s issued and outstanding common stock at a 1.196-for-1 ratio, which was effected on June 7, 2018. The par value of common stock and redeemable convertible preferred stock was not adjusted as a result of the stock split. All issued and outstanding common stock, options to purchase common stock and per share amounts contained in the financial statements have been adjusted to reflect the stock split for all periods presented. Liquidity The Company has incurred net losses from operations since inception and has an accumulated deficit of $91.1 million as of June 30, 2019. The Company’s ultimate success depends on the outcome of its research and development activities. The Company expects to incur additional losses in the future and it anticipates the need to raise additional capital to fully implement its business plan. Through June 30, 2019, the Company has financed its operations through private placements of redeemable convertible preferred stock, convertible promissory notes, and an initial public offering (IPO) of common stock. On June 19, 2018, the Company’s registration statement on Form S-1 (File No. 333-225235) relating to its IPO of common stock became effective. The IPO closed on June 22, 2018, at which time the Company issued 7,187,500 shares of its common stock at a price of $17.00 per share, which included shares issued upon the underwriters’ exercise of their overallotment option to purchase 937,500 additional shares. In addition, upon closing the IPO, all outstanding shares of the redeemable convertible preferred stock and warrants converted into 24,231,517 shares of common stock. As of December 31, 2018, there are no shares of redeemable convertible preferred stock outstanding. Upon completion of the IPO, the Company received an aggregate of $111.0 million in cash, net of underwriting discounts and commissions, and after deducting offering costs paid by the Company. The Company will need to obtain additional financing in the future and may seek financing through the issuance of our common stock, through other equity or debt financings or through collaborations or partnerships with other companies. The amount and timing of the Company’s future funding requirements will depend on many factors, including the pace and results of the Company’s clinical development efforts for AG10 and other research and development activities. The Company may not be able to raise additional capital on terms acceptable to the Company, or at all, and any failure to raise capital as and when needed would compromise the Company’s ability to execute on our business plan and the Company may have to significantly delay, scale back, or discontinue the development of AG10 or curtail any efforts to expand the Company’s product pipeline. |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 6 Months Ended |
Jun. 30, 2019 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | Note 2. Summary of significant accounting policies Basis of preparation These unaudited condensed financial statements have been prepared in accordance with United States generally accepted accounting principles, or GAAP. These unaudited condensed financial statements include transactions with , a controlling stockholder in the Company. For the periods presented, BBP LLC has provided consulting and management services to the Company in the ordinary course of business, including certain executive personnel, facility related costs, advisory services, insurance costs, and other general corporate expenses. These allocations were made based on direct usage, when identifiable, with the remainder allocated primarily based on a proportional share of headcount. The Company’s historical financial statements do not purport to reflect what the Company’s results of operations, financial position, or cash flows would have been if the Company had operated as an independent entity during the periods presented. Management believes the basis on which the expenses have been allocated to be a reasonable reflection of the utilization of services provided to or the benefit received by the Company during the periods presented. For more information on the allocated costs and related party transactions, see Note 6. Unaudited interim condensed financial statements The accompanying unaudited condensed financial statements have been prepared in accordance with GAAP and applicable rules and regulations of the Securities and Exchange Commission, or the SEC, regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information required by GAAP for complete financial statements. These unaudited interim condensed financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Company’s financial information. The results of operations for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any future year or interim period. The accompanying unaudited interim condensed financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2018 included in the Company’s Annual Report on Form 10-K, filed with the SEC on April 15, 2019. Use of estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to the fair value of the redemption feature embedded derivative liability, the fair value of the redeemable convertible preferred stock tranche liability, the fair value of the redeemable convertible preferred stock warrant liability, the fair value of the Company’s common stock, stock-based compensation, the useful lives of fixed assets, accruals for research and development activities, and income taxes. Management bases its estimates on historical experience and on other relevant assumptions that management believes to be reasonable under the circumstances. Actual results could differ from those estimates. Concentrations of credit risk Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents and short-term investments. All the Company’s funds are held by one financial institution that management believes is of high credit quality. Such deposits may, at times, exceed federally insured limits. Cash and cash equivalents All highly-liquid investments with an original maturity date of three months or less when purchased that are readily convertible into cash and have an insignificant interest rate risk are considered to be cash equivalents. Fair value of financial instruments The carrying amount of the Company’s financial instruments, including accounts payable and accrued expenses and other payables approximate fair value due to their short-term maturities. See Note 3 Fair value measurements regarding the fair value of the Company’s embedded derivative liability related to its convertible promissory notes, redeemable convertible preferred stock tranche liability, and redeemable convertible preferred stock warrant liability. Impairment of long-lived assets The Company reviews long-lived assets, primarily comprised of property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability is measured by comparison of the carrying amount to the estimated undiscounted future cash flows which the assets or asset groups are expected to generate. If such assets are considered to be impaired, the impairment to be recognized is the amount by which the carrying amount of the assets or asset groups exceeds the estimated discounted future cash flows arising from the assets or asset groups. There have been no such impairments of long-lived assets for any of the periods presented. Accrued repurchase liability for common stock The Company records as a liability, within accrued expenses and other current liabilities, the purchase price of unvested common stock that the Company has a right to repurchase if and when the stockholder ceases to be a service provider to the Company before the end of the requisite service period. The proceeds are recorded as a liability and the proceeds related to the vested common stock are reclassified to additional paid-in-capital as the Company’s repurchase right lapses. Redeemable convertible preferred stock tranche liability The Company determined that its obligations to issue additional shares of preferred stock upon the achievement of certain milestones or at the option of the respective holders of such shares represent freestanding financial instruments. These instruments were initially measured at fair value and were subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. The liability was settled upon the issuance of Series B redeemable convertible preferred stock (Series B Preferred Stock) in May 2018. Embedded derivative liability and deemed dividend The Company determined that the automatic conversion of the Note and Warrant Purchase Agreement with BBP LLC and the Board of Trustees of the Leland Stanford Junior University, or Stanford, (the Convertible Promissory Notes) payable issued in February 2018 into new shares of preferred stock at 70% of the issuance price of such shares upon the closing of a qualified financing was an embedded derivative liability to be measured at fair value. As this instrument was issued to stockholders, the Company treated the initial recognition as a deemed dividend included in additional paid-in-capital at its fair value of $6.5 million. The embedded derivative liability was subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. The embedded derivative liability balance was settled upon the conversion of the convertible promissory notes into Series B Preferred Stock in March 2018. The deemed dividend impacted loss available to common stockholders and earnings per share for the six months ended June 30, 2018 Gain on extinguishment of convertible promissory notes payable In March 2018, upon the conversion of the Convertible Promissory Notes into Series B Preferred Stock the Company recognized a $7.4 million gain on debt extinguishment. As the Convertible Promissory Notes were issued to stockholders, we treated the gain on debt extinguishment as a capital contribution included in additional paid-in-capital. The $7.4 million impacted loss available to common stockholders and net loss per share for the six months ended June 30, 2018. Net loss attributable to common stockholders and net loss per share Basic net loss per common share is calculated by dividing net loss attributable to common stockholders, taking into account the deemed dividend and gain on extinguishment of Convertible Promissory Notes payable, by the weighted-average number of shares of common stock outstanding during the period, less shares subject to repurchase and without consideration for potentially dilutive securities. Diluted net loss per common share is the same as basic net loss attributable to common stockholders per share since the effects of potentially dilutive securities are antidilutive given the Company’s loss position. Rec ently issued accounting standards adopted Effective January 1, 2019, the Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (“ASU 2016-02”) using the required modified retrospective approach. ASU 2016-02 requires lessees to record most leases on their balance sheets but recognize expenses on their income statements in a manner similar to current accounting. Upon transition under ASU 2016-02, the Company elected the suite of practical expedients as a package applied to all of its leases, including (i) not reassessing whether any expired or existing contracts are or contain leases, (ii) not reassessing the lease classification for any expired or existing leases, and (iii) not reassessing initial direct costs for any existing leases. For new leases, the Company will determine if an arrangement is or contains a lease at inception. Leases are included as right-of-use (“ROU”) assets within other assets and ROU liabilities within accrued expenses and other liabilities and within other long-term liabilities on the Company’s condensed balance sheets. In addition, the Company elected to exclude from its balance sheets recognition of leases having a term of 12 months or less (short-term leases) and elected to not separate lease components and non-lease components for its long-term real estate leases. ROU liabilities are recognized at the commencement date based on the present value of lease payments over the lease term and ROU assets are based on the liabilities adjusted for any prepaid or deferred rent. The Company’s leases do not provide an implicit rate. The Company uses its incremental borrowing rate based on the information available at the adoption date in determining the present value of lease payments. The ROU asset also includes any lease payments made and excludes lease incentives. Lease expense for lease payments is recognized on a straight-line basis over the lease term and is included in operating expenses on the condensed statements of operations. Variable lease payments include lease operating expenses. The lease term at the commencement date is determined by considering whether renewal options and termination options are reasonably assured of exercise. See discussion below in this Note 2 and in Note 12 for more detail on the Company's accounting policy with respect to lease accounting. Effective January 1, 2019, the Company adopted ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (“ASU 2018-07”), which aligns accounting for share-based payments issued to nonemployees to that of employees under the existing guidance of Topic 718, with certain exceptions. This update supersedes previous guidance for equity-based payments to nonemployees under Subtopic 505-50, Equity - Equity-Based Payments to Non-Employees. The adoption of ASU 2018-07 did not have a material impact on the Company’s condensed financial statements. In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. Additionally, the amendments expanded the disclosure requirements on the analysis of stockholders’ equity for interim financial statements. Under the amendments, a summary of changes in each caption of stockholders’ equity presented in the consolidated balance sheets must be provided in a note or separate statement. The final rule regarding stockholders’ equity was effective in the fourth quarter of 2018. The SEC provided relief on the effective date until the first quarter of 2019. The Company has provided this disclosure beginning January 1, 2019. Recently issued accounting standards not yet adopted In August 2018, the FASB issued ASU No. 2018-13, Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement , which amends ASC 820, Fair Value Measurement. This ASU modifies the disclosure requirements for fair value measurements by removing, modifying, or adding certain disclosures. The effective date is the first quarter of fiscal year 2020, with early adoption permitted for the removed disclosures and delayed adoption until fiscal year 2020 permitted for the new disclosures. The removed and modified disclosures will be adopted on a retrospective basis and the new disclosures will be adopted on a prospective basis. The Company is currently evaluating the impact that ASU 2018-07 will have on the Company’s condensed financial statements. |
Fair Value Measurements
Fair Value Measurements | 6 Months Ended |
Jun. 30, 2019 | |
Fair Value Disclosures [Abstract] | |
Fair Value Measurements | Note Financial assets and liabilities are recorded at fair value. 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—Quoted prices in active markets for identical assets or liabilities; Level 2—Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value. There were no transfers between Level 1, Level 2 and Level 3 categories during the periods presented Financial assets measured and recognized at fair value are as follows (in thousands): June 30, 2019 Total Level 1 Level 2 Level 3 Assets: Money Market Funds $ 131,400 $ 131,400 $ — $ — Total $ 131,400 $ 131,400 $ — $ — December 31, 2018 Total Level 1 Level 2 Level 3 Assets: Money Market Funds $ 157,147 $ 157,147 $ — $ — Total $ 157,147 $ 157,147 $ — $ — In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value. There were no financial assets outside of cash equivalents in an operating account as of June 30, 2019 and December 31, 2018. There were no transfers between Level 1, Level 2 and Level 3 categories during the periods presented. There were no financial liabilities measured at fair value as of June 30, 2019 and December 31, 2018. There were no transfers between Level 1, Level 2 and Level 3 categories during the periods presented. Following is the activity related to Level 3 financial liabilities of the Company. Embedded derivative liability in the convertible promissory notes payable The Convertible Promissory Notes payable issued in February 2018 had a redemption feature which was determined to be an embedded derivative requiring bifurcation and separate accounting. The fair value of the derivative was determined based on an income approach that identified the cash flows using a “with-and-without” valuation methodology. The inputs used to determine the estimated fair value of the derivative instrument were based primarily on the probability of an underlying event triggering the embedded derivative occurring and the timing of such event. The following table sets forth a summary of the changes in the fair value of the Company’s embedded derivative liability in the (in thousands): Six Months Ended June 30, 2019 2018 Derivative instrument: Beginning balance $ — $ — Initial fair value of the embedded derivative liability issued with the Convertible Promissory Notes payable — 6,523 Change in fair value upon revaluation recognized in other income (expense), net — (100 ) Settlement of the embedded derivative liability — (6,423 ) Ending balance $ — $ — Redeemable convertible preferred stock tranche liability Series B redeemable convertible preferred stock tranche liability The fair value of the Series B redeemable convertible preferred stock tranche liability was based on significant inputs not observed in the market and thus represents a Level 3 measurement. probability-weighted expected return method ( The following table sets forth a summary of the changes in the fair value of the Company’s Series B redeemable convertible preferred stock tranche liability as follows (in thousands): Six Months Ended June 30, 2019 2018 Redeemable convertible preferred stock tranche liability: Beginning balance $ — $ — Issuance of Series B redeemable convertible preferred stock tranche liability — 64 Change in fair value upon revaluation recognized in other income (expense), net — 630 Settlement of redeemable convertible preferred stock tranche liability due to the issuance of redeemable convertible preferred stock — (694 ) Ending balance $ — $ — Redeemable convertible preferred stock warrant liability The fair value of the redeemable convertible preferred stock warrant liability (see Note 5) is based on significant inputs not observed in the market and thus represents a Level 3 measurement. The Company estimated the fair value of the redeemable convertible preferred stock warrant liability using the Black-Scholes option pricing model (see Note 8). The following table sets forth a summary of the changes in the fair value of the Company’s redeemable convertible preferred stock warrant liability (in thousands): Six Months Ended June 30, 2019 2018 Redeemable convertible preferred stock warrant liability: Beginning balance $ — $ — Issuance of redeemable convertible preferred stock warrant liability — 878 Change in fair value upon revaluation recognized in other income (expense), net — 2,628 Reclassification of redeemable convertible preferred stock warrant liability to common stock at closing of initial public offering — (3,506 ) Ending balance $ — $ — |
Condensed Balance Sheet Compone
Condensed Balance Sheet Components | 6 Months Ended |
Jun. 30, 2019 | |
Balance Sheet Related Disclosures [Abstract] | |
Condensed Balance Sheet Components | Note 4. Condensed balance sheet components Property and equipment, net Property and equipment, net consisted of the following (in thousands): June 30, December 31, 2019 2018 Leasehold improvements $ 86 $ 86 Computer equipment 110 87 Office furniture and equipment 96 96 Total Property and equipment, cost 292 269 Less: Accumulated depreciation and amortization (88 ) (60 ) Total property and equipment, net $ 204 $ 209 The Company recognized $18,000 and $33,000 of depreciation and amortization expense during the three and six months ended June 30, 2019, respectively, and $14,000 and $24,000 of depreciation and amortization expense during the three and six months ended June 30, 2018, respectively. Accrued expenses and other current liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): June 30, December 31, 2019 2018 Accrued research and development costs $ 2,602 $ 2,055 Accrued employee related expenses 1,102 78 Liability for unvested stock, short-term 147 142 Accrued other current liabilities 176 302 Total accrued expenses and other current liabilities $ 4,027 $ 2,577 As of June 30, 2019, and December 31, 2018, $164,000 and $244,000, respectively, related to the long-term liability for unvested stock were recorded in other liabilities. Lease liabilities Lease liabilities consisted of the following (in thousands): June 30, December 31, 2019 2018 Lease liabilities $ 276 $ — Lease liabilities, non-current 782 — Total lease liabilities $ 1,058 $ — |
Convertible Promissory Notes
Convertible Promissory Notes | 6 Months Ended |
Jun. 30, 2019 | |
Debt Disclosure [Abstract] | |
Convertible Promissory Notes | Note 5. Convertible promissory notes In February 2018, the Company entered into a Note and Warrant Purchase Agreement with BBP LLC and Stanford (the Convertible Promissory Notes). The Company issued two Convertible Promissory Notes in an aggregate principal amount of $10.0 million. The Convertible Promissory Notes had a maturity date of the earliest of a qualified financing, a deemed liquidation event, a qualified initial public offering, or February 2019. The Convertible Promissory Notes had an annual interest rate of 5.0%. The Convertible Promissory Notes were convertible into future preferred stock at a 30% discount to the price paid by investors in the Company’s next preferred equity financing of at least $10.0 million or convertible into common stock at the price per share in an IPO with aggregate proceeds of at least $30.0 million. In connection with the Convertible Promissory Notes, the Company issued warrants for the purchase of $4.0 million in shares of the Company’s Series Seed redeemable convertible preferred stock or the Company’s preferred stock in the next equity financing. The warrant exercise period commenced upon the earlier of the closing of the next qualified financing and the consummation of a deemed liquidation event. The exercise price of the warrant was the price per share in the next equity financing if the warrant was exercisable for the Company’s redeemable convertible preferred stock in the next qualified financing, or $1.3248 per share if the warrant was exercisable for shares of Series Seed redeemable convertible preferred stock. Upon issuance of the Convertible Promissory Notes, the Company recorded the fair value of the warrants of $0.9 million as a debt discount and redeemable convertible preferred stock warrant liability. The Company also determined that a beneficial conversion feature existed at the time the Convertible Promissory Notes were issued because the fair value of the securities into which the Convertible Promissory Notes were convertible at the time of issuance, Series Seed redeemable convertible preferred stock, was greater than the effective conversion price on the borrowing date. Accordingly, the Company recorded a beneficial conversion feature of $9.1 million. The beneficial conversion feature was recorded as a debt discount with an offset to additional paid-in-capital. The discounts associated with both the warrants and beneficial conversion feature were amortized to interest expense using the effective interest method through February 2019, the contractual maturity date of the Convertible Promissory Notes. During the three and six months ended June 30, 2018, the Company recognized interest expense of $0.0 million and $1.0 million, respectively. The Convertible Promissory Notes also contained a redemption feature that was determined to be an embedded derivative requiring bifurcation. The fair value of the embedded derivative liability at issuance was determined to be $6.5 million and was recorded as a deemed dividend as the transaction was with stockholders. Changes in the fair value of the redeemable convertible preferred stock warrant liability and embedded derivative liability have been recorded within other income (expense), net, in the statement of operations. Upon completion of the Series B redeemable convertible preferred stock (Series B Preferred Stock) financing in March 2018, the Convertible Promissory Notes were redeemed under their qualified financing redemption feature whereby the aggregate of the outstanding principal and accrued interest balance of the Convertible Promissory Notes of $10.0 million was converted into 1,324,823 shares of Series B preferred stock at a conversion price of $7.5844 per share resulting in issuance of $14.4 million of Series B Preferred Stock. The redemption of the Convertible Promissory Notes was accounted for as a debt extinguishment, which resulted in a gain of $7.4 million. The extinguishment gain was recognized in equity and included the reacquisition of the beneficial conversion feature which was measured using the intrinsic value of the conversion option at the extinguishment date of $14.4 million and the settlement of the embedded derivative liability of $6.5 million. This gain was recorded in additional paid-in-capital since the holders of the Convertible Promissory Notes were stockholders and the arrangement was considered a capital transaction. The warrants associated with the Convertible Promissory Notes also became warrants to purchase 369,180 shares of the Series B Preferred Stock at an exercise price of $10.8348 per share. These warrants were net exercised upon the completion of the IPO into 206,247 shares of the Company’s common stock. During the three and six months ended June 30, 2018, the Company recognized expense associated with these warrants of $2.6 million and $2.6 million, respectively |
Related Party Transactions
Related Party Transactions | 6 Months Ended |
Jun. 30, 2019 | |
Related Party Transactions [Abstract] | |
Related Party Transactions | Note 6. Related party transactions BridgeBio Pharma LLC BridgeBio Pharma LLC and its affiliates, or BBP LLC, is a controlling stockholder in the Company, as it owned 64% and 61% of the Company’s total outstanding shares as of June 30, 2019 and December 31, 2018, respectively. In April 2016, the Company began receiving consulting, management, facility and infrastructure services pursuant to a services agreement with BBP LLC. The initial agreement was entered into on March 1, 2016 and was superseded by the subsequent agreement that was effective as of May 1, 2017. The Company incurred the following expenses under the agreement with BBP LLC (in thousands): Three Months Six Months June 30, June 30, 2019 2018 2019 2018 Rent $ (8 ) $ 11 $ (11 ) $ 19 Facility (4 ) 57 75 102 Consulting 56 370 153 657 $ 44 $ 438 $ 217 $ 778 As of June 30, 2019, and December 31, 2018, the Company had outstanding receivables from BBP LLC of $0.2 million and $34,000, respectively, related to providing services to other related companies of BBP LLC. As of June 30, 2019, and December 31, 2018, the Company had outstanding liabilities due to BBP LLC of $0.3 million and $0.3 million, respectively. Dr. Graef Consulting Agreement In April 2016, the Company entered into a consulting agreement with Dr. Graef, one of the Company’s founders. Pursuant to the consulting agreement, Dr. Graef agreed to provide consulting services in connection with the discovery and development of novel TTR stabilizers. As compensation for these services, Dr. Graef is entitled to an annual fee in the amount of up to $150,000 and reimbursement by the Company for pre-approved expenses. The consulting agreement has a term of four years but may be terminated by either party for any reason with thirty days’ prior notice. As of June 20, 2018, in connection with the Company’s initial public offering, the ownership percentage of the Company’s stock held by Dr. Graef decreased, whereby the Company no longer considered Dr. Graef a related party. Dr. Alhamadsheh Consulting Agreement In August 2016, the Company entered into a consulting agreement with Dr. Alhamadsheh, one of the Company’s founders. Pursuant to the consulting agreement, Dr. Alhamadsheh agreed to provide consulting services in connection with the discovery and development of novel TTR stabilizers. As compensation for these services, Dr. Alhamadsheh is entitled to an annual fee in the amount of up to $115,000 and reimbursement by the Company for pre-approved expenses. The consulting agreement has a term of four years but may be terminated by either party for any reason with thirty days’ prior notice. As of June 20, 2018, in connection with the Company’s initial public offering, the ownership percentage of the Company’s stock held by Dr. Alhamadsheh decreased, whereby the Company no longer considered Dr. Alhamadsheh a related party. The Company incurred the following expenses (benefit) for services under these consulting agreements and stock-based compensation (in thousands): Three Months Six Months June 30, June 30, 2019 2018 2019 2018 Dr. Graef $ 38 $ 38 $ 76 $ 76 Dr. Alhamadsheh 29 29 58 58 $ 67 $ 67 $ 134 $ 134 Option award to Dr. Huh In May 2018, our board of directors approved a grant to Dr. Huh (a member of our board of directors) of an option to purchase 83,720 shares of our common stock pursuant to the Company’s 2018 Stock Option and Incentive Plan (the “2018 Plan”). in equal annual installments over three years from the grant date, subject to Dr. Huh’s continued service as a director through the applicable vesting dates. The award is subject to full accelerated vesting upon a “sale event,” as defined in the 2018 Plan. or the three and six months ended June 30, 2018. For the three and six months ended June 30, 2019 the Company recorded no expense related to these awards. |
Redeemable Convertible Preferre
Redeemable Convertible Preferred Stock | 6 Months Ended |
Jun. 30, 2019 | |
Temporary Equity Disclosure [Abstract] | |
Redeemable Convertible Preferred Stock | Note 7. Redeemable convertible preferred stock In March 2018, the Company sold an aggregate of 1,476,715 shares of Series B redeemable convertible preferred stock financing in an initial closing for total gross proceeds of $16.0 million. An additional 4,430,162 shares of Series B Preferred Stock The Company recorded the redeemable convertible preferred stock tranche liability incurred in connection with its Series B Preferred Stock In May 2018, the Company issued 4,430,162 shares of Series B Preferred Stock at a purchase price of $10.8348 per share, for total proceeds of $48.0 million. The Company exercised its option to issue the Series B Preferred Stock and at the time the tranche liability was remeasured at $0.7 million and then was reclassified to Series B redeemable convertible preferred stock upon the closing of the sale of additional shares. Following the closing of the IPO, all outstanding shares of the Series Seed and Series B Preferred Stock converted into 24,025,270 shares of common stock and the related carrying value was reclassified to common stock and additional paid-in-capital. |
Redeemable Convertible Prefer_2
Redeemable Convertible Preferred Stock Tranche Liability | 6 Months Ended |
Jun. 30, 2019 | |
Temporary Equity Disclosure [Abstract] | |
Redeemable Convertible Preferred Stock Tranche Liability | Note 8. Redeemable convertible preferred stock tranche liability In March 2018, the Company entered into a Series B Preferred Stock Purchase Agreement, or the Series B Agreement, for the issuance of up to 7,231,700 shares of Series B redeemable convertible preferred stock at a price of $10.8348 per share in two closings. Upon the initial closing on March 29, 2018, 1,476,715 shares of Series B redeemable convertible preferred stock were issued for gross proceeds of $16.0 million and 1,324,823 shares were issued upon conversion of the outstanding Convertible Promissory Notes principal balance and accrued interest of $10.0 million into $14.4 million of Series B Preferred Stock. The Series B Agreement provided that the Company could issue an additional 4,430,162 shares under the same terms as the initial closing, in an additional closing contingent upon the achievement of certain milestone. Either the investors or the Company could provide written notice for the additional closing to occur. The Company determined that its obligation to issue additional shares of its redeemable convertible preferred stock and the Company’s right to request investors to purchase additional shares of its redeemable convertible preferred stock represents a freestanding financial instrument. The freestanding redeemable convertible preferred stock tranche liability (Series B Tranche Liability) was initially recorded at fair value, with fair value changes recorded within other income (expense), net in the statement of operations. The Company continued to adjust the Series B Tranche Liability for changes in the fair value until the settlement of the redeemable convertible preferred stock additional closing in May 2018. The Company recorded a Series B Tranche Liability in March 2018 of $0.1 million related to the Series B Preferred Stock. The Company exercised its option to issue the Series B Preferred Stock and at the time the tranche liability was remeasured at $0.7 million in May 2018, and then reclassified to Series B redeemable convertible preferred stock upon the |
Stockholders' Equity and Stock-
Stockholders' Equity and Stock-Based Compensation | 6 Months Ended |
Jun. 30, 2019 | |
Stockholders Equity And Stock Based Compensation [Abstract] | |
Stockholders' Equity and Stock-Based Compensation | Note 9. Stockholders’ equity and stock-based compensation Common stock The Company has reserved shares of common stock for issuance as follows: As of June 30, 2019 2018 Options issued and outstanding 1,454,461 881,612 Options available for future grants 537,345 490,360 Employee Stock Purchase Plan shares available for future grants 104,540 143,520 Total 2,096,346 1,515,492 Stock options The following table summarizes the Company’s stock option activity for the six months ended June 30, 2019: Weighted- Average Weighted- Average Aggregate Options Exercise Remaining Intrinsic Available for Options Price Per Contractual Value Grant Outstanding Share Term (years) (in thousands) Outstanding—December 31, 2018 747,057 1,329,762 $ 8.55 9.40 $ 6,928 Options granted (209,712 ) 209,712 $ 27.22 Options exercised — (85,013 ) $ 1.32 Outstanding—June 30, 2019 537,345 1,454,461 $ 11.66 9.07 $ 28,246 Options exercisable – June 30, 2019 251,447 $ 6.26 8.69 $ 6,240 Options vested and expected to vest – June 30, 2019 1,454,461 $ 11.66 9.07 $ 28,246 Employee stock options valuation The fair value of employee and non-employee director stock option awards was estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions: Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Expected term in years 6.07 6.08 6.07 6.08 Expected volatility 72.27 % 69.76 % 72.31 % 69.59 % Risk-free interest rate 2.07 % 2.82 % 2.10 % 2.78 % Dividend yield — — — — Weighted average fair value of share-based awards granted $ 18.62 $ 7.88 $ 18.22 $ 7.50 Stock options granted to non-employees Stock-based compensation related to stock options granted to non-employees is recognized as the stock options are earned. The fair value of the stock options granted to non-employees was calculated at each reporting date using the Black-Scholes option-pricing model with the following assumptions: Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Expected term in years N/A 9.70 6.08 9.70 Expected volatility N/A 68.31 % 73.54 % 68.31 % Risk-free interest rate N/A 2.84 % 2.74 % 2.84 % Dividend yield N/A — — — During the three and six months ended June 30, 2019, and 2018, the Company granted 0, 18,500, 35,880 and 35,880 shares, respectively, to non-employee consultants. The Company recognized stock-based compensation expense for non-employee awards during the three and six months ended June 30, 2019, and 2018 of $0.1 million, $0.1 million, $0.1 million, and $0.2 million, respectively. Accrued repurchase liability for common stock early exercises Stock awards granted pursuant to the 2016 Equity Incentive Plan, or the 2016 Plan, permitted option holders to elect to exercise unvested options in exchange for unvested common stock. Awards granted under the 2016 Plan that are exercised prior to vesting will continue to vest according to the respective award agreement, and such unvested shares are subject to repurchase by the Company at the optionee’s original exercise price or fair market value in the event the optionee’s service with the Company voluntarily or involuntarily terminates. As of June 30, 2019, and December 31, 2018, 709,927 and 896,034 shares, respectively, remained subject to a repurchase right by the Company, with a related liability included in accrued expenses and other liabilities in the balance sheet of $311,000 and $386,000, respectively. Stock-based compensation expense Total stock-based compensation expense related to all our stock-based awards was recorded in the statements of operations as follows (in thousands): Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Research and development $ 552 $ 443 $ 1,004 $ 621 General and administrative 614 176 1,126 386 Total stock-based compensation expense $ 1,166 $ 619 $ 2,130 $ 1,007 As of , there was $12.5 million of total unrecognized compensation cost related to unvested stock-based compensation arrangements under the 2016 and 2018 Plans. The unrecognized stock-based compensation cost is expected to be recognized over a weighted-average period of 2.66 years |
Net loss per Share
Net loss per Share | 6 Months Ended |
Jun. 30, 2019 | |
Earnings Per Share [Abstract] | |
Net loss per Share | 10. Net loss per share The Company’s potentially dilutive shares, which include outstanding common stock options, unvested common shares subject to repurchase, convertible preferred stock and convertible preferred stock warrants, have not been included in the computation of diluted net loss per common share for all periods presented, as the results would be anti-dilutive. Such potentially dilutive shares are excluded when the effect would be to reduce net Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Numerator: Net loss attributable to common stockholders $ (14,053 ) $ (11,381 ) $ (25,786 ) $ (19,344 ) Denominator: Weighted average common shares outstanding 36,834,135 8,972,945 36,801,357 7,092,069 Weighted average unvested common shares subject to repurchase (524,395 ) (863,292 ) (558,543 ) (763,242 ) Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted 36,309,740 8,109,653 36,242,814 6,328,827 Net loss per share attributable to common stockholders $ (0.39 ) $ (1.40 ) $ (0.71 ) $ (3.06 ) The following shares of potentially dilutive securities have been excluded from the diluted net loss per share computations for the three and six months ended June 30, 2019 and 2018 because their inclusion would be anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Employee Stock Purchase Plan shares 1,475 — 1,475 — Options to purchase common stock 1,454,461 881,612 1,454,461 881,612 Common stock subject to vesting or repurchase 490,241 831,339 490,241 831,339 Total 1,946,177 1,712,951 1,946,177 1,712,951 |
Stanford License Agreement
Stanford License Agreement | 6 Months Ended |
Jun. 30, 2019 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Stanford License Agreement | 11. Stanford license agreement In April 2016, the Company entered into a license agreement with Stanford, relating to the Company’s drug discovery and development initiatives. Under this agreement, the Company has been granted certain worldwide exclusive licenses to use the licensed compounds. In consideration for the license the Company paid an upfront license payment of $25,000 in April 2016 and also issued 56,809 shares of common stock. In March 2017, the Company paid Stanford an annual license fee of $10,000, which was recorded as research and development expense during the year ended December 31, 2017. The Company may also be required to make future payments of up to approximately $1.0 million to Stanford upon achievement of specific intellectual property, clinical and regulatory milestone events, as well as pay royalties in the low single digits on future net sales, if any. In addition, the Company is obligated to pay Stanford a percentage of non-royalty revenue received by the Company from its sublicensees, with the amount owed decreasing annually for three years based on when the applicable sublicense agreement is executed. In March 2018, the Company recognized $50,000 of research and development expense in connection with the achievement of a development milestone under the Stanford agreement. In February 2019, the Company recognized $200,000 of research and development expense in connection with the achievement of a development milestone under the Stanford agreement. During the three and six months ended June 30, 2019, and 2018, the Company recognized expense of $0.0 million, $0.2 million, $0.0 million, and $0.1 million, respectively, in connection with this agreement. |
Commitments and Contingencies
Commitments and Contingencies | 6 Months Ended |
Jun. 30, 2019 | |
Commitments And Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | 12. Commitments and contingencies Lease arrangements In September 2017, the Company entered into a one-year operating lease for laboratory facilities in San Francisco, California. In November 2017, the Company entered into an operating lease for an administrative facility in San Francisco, California, which expires in November 2022. The Company has provided a security deposit of $158,000 as collateral for the lease, which is included in other assets on the condensed balance sheet at June 30, 2019. On March 27, 2019 the Company entered into an amendment to the lease dated November 14, 2017. In connection with the amendment the Company will lease 10,552 rentable square feet. The amended lease is for 87 months and have $6.4 million of payments under this lease. The commencement date of the amendment to the lease is expected to occur in August 2019. Upon the adoption of ASU 2016-02 on January 1, 2019, the Company recognized a lease liability and related ROU asset of $1.2 million and $1.1 million, respectively, based on the present value of lease payments for the remaining term of our existing lease. As of June 30, 2019, total ROU assets and lease liabilities were approximately $1.0 million and $1.1 million, respectively. All operating lease expense is recognized on a straight-line basis over the lease term. Other information related to the operating lease: Six Months Ended June 30, 2019 Cash payments over lease term (in thousands) $ 1,175 Weighted average remaining lease term (months) 41 Weighted average discount rate (1) 6 % (1) Because the rate implicit in our lease was not readily determinable, the Company used the Company’s incremental borrowing rate. In determining our incremental borrowing rate for each lease, we considered recent rates on secured borrowings, observable risk-free interest rates and credit spreads correlating to our creditworthiness, the impact of collateralization and the term of each of our lease agreements. Future minimum lease payments as of June 30, 2019 are as follows (in thousands): Operating Year Lease Commitments 2019 (remaining six months) $ 164 2020 337 2021 347 2022 327 Total 1,175 Less imputed lease interest (117 ) Total lease liabilities $ 1,058 The Company’s rent expense was $0.1 million and $0.2 million for the three and six months ended June 30, 2019 and $0.1 million and $0.2 million for the three and six months ended June 30, 2018. The amounts include the amounts incurred pursuant to the service agreement with BridgeBio Services, Inc., an affiliate of BridgeBio Pharma LLC (see Note 6). Variable lease payments for operating expenses were immaterial for the three and six months ended June 30, 2019. Indemnification In the ordinary course of business, the Company may provide indemnifications of varying scope and terms to vendors, lessors, business partners, board members, officers, and other parties with respect to certain matters, including, but not limited to, losses arising out of breach of such agreements, services to be provided by the Company, negligence or willful misconduct of the Company, violations of law by the Company, or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with directors and certain officers and employees that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors, officers or employees. No demands have been made upon the Company to provide indemnification under such agreements, and thus, there are no claims that the Company is aware of that could have a material effect on the Company’s balance sheets, statements of operations, or statements of cash flows. |
Income Taxes
Income Taxes | 6 Months Ended |
Jun. 30, 2019 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | 13. Income taxes Income tax expense during interim periods is based on applying an estimated annual effective income tax rate to year-to-date income, plus any significant unusual or infrequently occurring items which are recorded in the interim period. The provision for income taxes for the three and six months ended June 30, 2019 and 2018 differs from the amount that would be provided by applying the statutory U.S. federal income tax rate of 21%, to pre-tax income primarily due to (i) an increase in uncertain tax positions related to tax credits generated during the quarter and (ii) for the three and six months ended June 30, 2019 and 2018, a full valuation allowance was in effect, which reduced the Company’s net tax expense to zero. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion, or all, of the Company’s deferred tax assets will not be realized. In making such determination, the Company considers all available positive and negative evidence, including future reversals of temporary differences, tax-planning strategies and projected future taxable income and results of operations. If the Company concludes that it is more likely than not that some portion, or all, of its deferred tax assets will not be realized, the tax asset is reduced by a valuation allowance. At December 31, 2018, the Company maintained a full valuation allowance on its net deferred tax assets. The Company assesses the appropriateness of its valuation allowance on a quarterly basis. As of June 30, 2019, there was no change in the Company’s assessment of the realizability of its deferred tax assets, and the full valuation allowance remains in effect. In June 2019, the Company entered into a tax sharing agreement with BridgeBio Pharma, Inc. Based on the agreement, in the case that the Company and BridgeBio Pharma, Inc. file a consolidated or combined tax return and BridgeBio Pharma, Inc. utilizes the Company’s tax attributes, BridgeBio Pharma, Inc. will pay the Company the tax benefit it takes on a “with and without” basis. Based on the current ownership structure at June 30, 2019, the Company and BridgeBio Pharma, Inc. may qualify for filing a consolidated or combined tax returns in certain tax jurisdictions. |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 6 Months Ended |
Jun. 30, 2019 | |
Accounting Policies [Abstract] | |
Basis of Preparation | Basis of preparation These unaudited condensed financial statements have been prepared in accordance with United States generally accepted accounting principles, or GAAP. These unaudited condensed financial statements include transactions with , a controlling stockholder in the Company. For the periods presented, BBP LLC has provided consulting and management services to the Company in the ordinary course of business, including certain executive personnel, facility related costs, advisory services, insurance costs, and other general corporate expenses. These allocations were made based on direct usage, when identifiable, with the remainder allocated primarily based on a proportional share of headcount. The Company’s historical financial statements do not purport to reflect what the Company’s results of operations, financial position, or cash flows would have been if the Company had operated as an independent entity during the periods presented. Management believes the basis on which the expenses have been allocated to be a reasonable reflection of the utilization of services provided to or the benefit received by the Company during the periods presented. For more information on the allocated costs and related party transactions, see Note 6. |
Unaudited Interim Condensed Financial Statements | Unaudited interim condensed financial statements The accompanying unaudited condensed financial statements have been prepared in accordance with GAAP and applicable rules and regulations of the Securities and Exchange Commission, or the SEC, regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information required by GAAP for complete financial statements. These unaudited interim condensed financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Company’s financial information. The results of operations for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any future year or interim period. The accompanying unaudited interim condensed financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2018 included in the Company’s Annual Report on Form 10-K, filed with the SEC on April 15, 2019. |
Use of Estimates | Use of estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to the fair value of the redemption feature embedded derivative liability, the fair value of the redeemable convertible preferred stock tranche liability, the fair value of the redeemable convertible preferred stock warrant liability, the fair value of the Company’s common stock, stock-based compensation, the useful lives of fixed assets, accruals for research and development activities, and income taxes. Management bases its estimates on historical experience and on other relevant assumptions that management believes to be reasonable under the circumstances. Actual results could differ from those estimates. |
Concentrations of Credit Risk | Concentrations of credit risk Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents and short-term investments. All the Company’s funds are held by one financial institution that management believes is of high credit quality. Such deposits may, at times, exceed federally insured limits. |
Cash and Cash Equivalents | Cash and cash equivalents All highly-liquid investments with an original maturity date of three months or less when purchased that are readily convertible into cash and have an insignificant interest rate risk are considered to be cash equivalents. |
Fair Value of Financial Instruments | Fair value of financial instruments The carrying amount of the Company’s financial instruments, including accounts payable and accrued expenses and other payables approximate fair value due to their short-term maturities. See Note 3 Fair value measurements regarding the fair value of the Company’s embedded derivative liability related to its convertible promissory notes, redeemable convertible preferred stock tranche liability, and redeemable convertible preferred stock warrant liability. |
Impairment of Long-Lived Assets | Impairment of long-lived assets The Company reviews long-lived assets, primarily comprised of property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability is measured by comparison of the carrying amount to the estimated undiscounted future cash flows which the assets or asset groups are expected to generate. If such assets are considered to be impaired, the impairment to be recognized is the amount by which the carrying amount of the assets or asset groups exceeds the estimated discounted future cash flows arising from the assets or asset groups. There have been no such impairments of long-lived assets for any of the periods presented. |
Accrued Repurchase Liability for Common Stock | Accrued repurchase liability for common stock The Company records as a liability, within accrued expenses and other current liabilities, the purchase price of unvested common stock that the Company has a right to repurchase if and when the stockholder ceases to be a service provider to the Company before the end of the requisite service period. The proceeds are recorded as a liability and the proceeds related to the vested common stock are reclassified to additional paid-in-capital as the Company’s repurchase right lapses. |
Redeemable Convertible Preferred Stock Tranche Liability | Redeemable convertible preferred stock tranche liability The Company determined that its obligations to issue additional shares of preferred stock upon the achievement of certain milestones or at the option of the respective holders of such shares represent freestanding financial instruments. These instruments were initially measured at fair value and were subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. The liability was settled upon the issuance of Series B redeemable convertible preferred stock (Series B Preferred Stock) in May 2018. |
Embedded Derivative Liability and Deemed Dividend | Embedded derivative liability and deemed dividend The Company determined that the automatic conversion of the Note and Warrant Purchase Agreement with BBP LLC and the Board of Trustees of the Leland Stanford Junior University, or Stanford, (the Convertible Promissory Notes) payable issued in February 2018 into new shares of preferred stock at 70% of the issuance price of such shares upon the closing of a qualified financing was an embedded derivative liability to be measured at fair value. As this instrument was issued to stockholders, the Company treated the initial recognition as a deemed dividend included in additional paid-in-capital at its fair value of $6.5 million. The embedded derivative liability was subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. The embedded derivative liability balance was settled upon the conversion of the convertible promissory notes into Series B Preferred Stock in March 2018. The deemed dividend impacted loss available to common stockholders and earnings per share for the six months ended June 30, 2018 |
Gain on Extinguishment of Convertible Promissory Notes Payable | Gain on extinguishment of convertible promissory notes payable In March 2018, upon the conversion of the Convertible Promissory Notes into Series B Preferred Stock the Company recognized a $7.4 million gain on debt extinguishment. As the Convertible Promissory Notes were issued to stockholders, we treated the gain on debt extinguishment as a capital contribution included in additional paid-in-capital. The $7.4 million impacted loss available to common stockholders and net loss per share for the six months ended June 30, 2018. |
Net Loss Attributable to Common Stockholders and Net Loss Per Share | Net loss attributable to common stockholders and net loss per share Basic net loss per common share is calculated by dividing net loss attributable to common stockholders, taking into account the deemed dividend and gain on extinguishment of Convertible Promissory Notes payable, by the weighted-average number of shares of common stock outstanding during the period, less shares subject to repurchase and without consideration for potentially dilutive securities. Diluted net loss per common share is the same as basic net loss attributable to common stockholders per share since the effects of potentially dilutive securities are antidilutive given the Company’s loss position. |
Recent Accounting Pronouncements | Rec ently issued accounting standards adopted Effective January 1, 2019, the Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (“ASU 2016-02”) using the required modified retrospective approach. ASU 2016-02 requires lessees to record most leases on their balance sheets but recognize expenses on their income statements in a manner similar to current accounting. Upon transition under ASU 2016-02, the Company elected the suite of practical expedients as a package applied to all of its leases, including (i) not reassessing whether any expired or existing contracts are or contain leases, (ii) not reassessing the lease classification for any expired or existing leases, and (iii) not reassessing initial direct costs for any existing leases. For new leases, the Company will determine if an arrangement is or contains a lease at inception. Leases are included as right-of-use (“ROU”) assets within other assets and ROU liabilities within accrued expenses and other liabilities and within other long-term liabilities on the Company’s condensed balance sheets. In addition, the Company elected to exclude from its balance sheets recognition of leases having a term of 12 months or less (short-term leases) and elected to not separate lease components and non-lease components for its long-term real estate leases. ROU liabilities are recognized at the commencement date based on the present value of lease payments over the lease term and ROU assets are based on the liabilities adjusted for any prepaid or deferred rent. The Company’s leases do not provide an implicit rate. The Company uses its incremental borrowing rate based on the information available at the adoption date in determining the present value of lease payments. The ROU asset also includes any lease payments made and excludes lease incentives. Lease expense for lease payments is recognized on a straight-line basis over the lease term and is included in operating expenses on the condensed statements of operations. Variable lease payments include lease operating expenses. The lease term at the commencement date is determined by considering whether renewal options and termination options are reasonably assured of exercise. See discussion below in this Note 2 and in Note 12 for more detail on the Company's accounting policy with respect to lease accounting. Effective January 1, 2019, the Company adopted ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (“ASU 2018-07”), which aligns accounting for share-based payments issued to nonemployees to that of employees under the existing guidance of Topic 718, with certain exceptions. This update supersedes previous guidance for equity-based payments to nonemployees under Subtopic 505-50, Equity - Equity-Based Payments to Non-Employees. The adoption of ASU 2018-07 did not have a material impact on the Company’s condensed financial statements. In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. Additionally, the amendments expanded the disclosure requirements on the analysis of stockholders’ equity for interim financial statements. Under the amendments, a summary of changes in each caption of stockholders’ equity presented in the consolidated balance sheets must be provided in a note or separate statement. The final rule regarding stockholders’ equity was effective in the fourth quarter of 2018. The SEC provided relief on the effective date until the first quarter of 2019. The Company has provided this disclosure beginning January 1, 2019. Recently issued accounting standards not yet adopted In August 2018, the FASB issued ASU No. 2018-13, Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement , which amends ASC 820, Fair Value Measurement. This ASU modifies the disclosure requirements for fair value measurements by removing, modifying, or adding certain disclosures. The effective date is the first quarter of fiscal year 2020, with early adoption permitted for the removed disclosures and delayed adoption until fiscal year 2020 permitted for the new disclosures. The removed and modified disclosures will be adopted on a retrospective basis and the new disclosures will be adopted on a prospective basis. The Company is currently evaluating the impact that ASU 2018-07 will have on the Company’s condensed financial statements. |
Fair Value Measurements (Tables
Fair Value Measurements (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Fair Value Disclosures [Abstract] | |
Schedule of Fair Value of Financial Assets | Financial assets measured and recognized at fair value are as follows (in thousands): June 30, 2019 Total Level 1 Level 2 Level 3 Assets: Money Market Funds $ 131,400 $ 131,400 $ — $ — Total $ 131,400 $ 131,400 $ — $ — December 31, 2018 Total Level 1 Level 2 Level 3 Assets: Money Market Funds $ 157,147 $ 157,147 $ — $ — Total $ 157,147 $ 157,147 $ — $ — |
Summary of Embedded Derivative in Convertible Note | The following table sets forth a summary of the changes in the fair value of the Company’s embedded derivative liability in the Six Months Ended June 30, 2019 2018 Derivative instrument: Beginning balance $ — $ — Initial fair value of the embedded derivative liability issued with the Convertible Promissory Notes payable — 6,523 Change in fair value upon revaluation recognized in other income (expense), net — (100 ) Settlement of the embedded derivative liability — (6,423 ) Ending balance $ — $ — |
Summary of Redeemable Convertible Preferred Stock Tranche Liability | The following table sets forth a summary of the changes in the fair value of the Company’s Series B redeemable convertible preferred stock tranche liability as follows (in thousands): Six Months Ended June 30, 2019 2018 Redeemable convertible preferred stock tranche liability: Beginning balance $ — $ — Issuance of Series B redeemable convertible preferred stock tranche liability — 64 Change in fair value upon revaluation recognized in other income (expense), net — 630 Settlement of redeemable convertible preferred stock tranche liability due to the issuance of redeemable convertible preferred stock — (694 ) Ending balance $ — $ — |
Summary of Redeemable Convertible Preferred Stock Warrant Liability | The following table sets forth a summary of the changes in the fair value of the Company’s redeemable convertible preferred stock warrant liability (in thousands): Six Months Ended June 30, 2019 2018 Redeemable convertible preferred stock warrant liability: Beginning balance $ — $ — Issuance of redeemable convertible preferred stock warrant liability — 878 Change in fair value upon revaluation recognized in other income (expense), net — 2,628 Reclassification of redeemable convertible preferred stock warrant liability to common stock at closing of initial public offering — (3,506 ) Ending balance $ — $ — |
Condensed Balance Sheet Compo_2
Condensed Balance Sheet Components (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Balance Sheet Related Disclosures [Abstract] | |
Schedule of Property and Equipment, Net | Property and equipment, net consisted of the following (in thousands): June 30, December 31, 2019 2018 Leasehold improvements $ 86 $ 86 Computer equipment 110 87 Office furniture and equipment 96 96 Total Property and equipment, cost 292 269 Less: Accumulated depreciation and amortization (88 ) (60 ) Total property and equipment, net $ 204 $ 209 |
Schedule of Accrued Expenses and Other Current Liabilities | Accrued expenses and other current liabilities consisted of the following (in thousands): June 30, December 31, 2019 2018 Accrued research and development costs $ 2,602 $ 2,055 Accrued employee related expenses 1,102 78 Liability for unvested stock, short-term 147 142 Accrued other current liabilities 176 302 Total accrued expenses and other current liabilities $ 4,027 $ 2,577 |
Schedule of Lease Liabilities | Lease liabilities consisted of the following (in thousands): June 30, December 31, 2019 2018 Lease liabilities $ 276 $ — Lease liabilities, non-current 782 — Total lease liabilities $ 1,058 $ — |
Related Party Transactions (Tab
Related Party Transactions (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
BridgeBio Pharma LLC | |
Related Party Transaction [Line Items] | |
Schedule of Expenses (Benefit) from Transactions with Related Party | The Company incurred the following expenses under the agreement with BBP LLC (in thousands): Three Months Six Months June 30, June 30, 2019 2018 2019 2018 Rent $ (8 ) $ 11 $ (11 ) $ 19 Facility (4 ) 57 75 102 Consulting 56 370 153 657 $ 44 $ 438 $ 217 $ 778 |
Founders | |
Related Party Transaction [Line Items] | |
Schedule of Expenses (Benefit) from Transactions with Related Party | The Company incurred the following expenses (benefit) for services under these consulting agreements and stock-based compensation (in thousands): Three Months Six Months June 30, June 30, 2019 2018 2019 2018 Dr. Graef $ 38 $ 38 $ 76 $ 76 Dr. Alhamadsheh 29 29 58 58 $ 67 $ 67 $ 134 $ 134 |
Stockholders' Equity and Stoc_2
Stockholders' Equity and Stock-Based Compensation (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
Summary of Reserved Shares of Common Stock for Issuance | The Company has reserved shares of common stock for issuance as follows: As of June 30, 2019 2018 Options issued and outstanding 1,454,461 881,612 Options available for future grants 537,345 490,360 Employee Stock Purchase Plan shares available for future grants 104,540 143,520 Total 2,096,346 1,515,492 |
Summary of Stock Option Activity | The following table summarizes the Company’s stock option activity for the six months ended June 30, 2019: Weighted- Average Weighted- Average Aggregate Options Exercise Remaining Intrinsic Available for Options Price Per Contractual Value Grant Outstanding Share Term (years) (in thousands) Outstanding—December 31, 2018 747,057 1,329,762 $ 8.55 9.40 $ 6,928 Options granted (209,712 ) 209,712 $ 27.22 Options exercised — (85,013 ) $ 1.32 Outstanding—June 30, 2019 537,345 1,454,461 $ 11.66 9.07 $ 28,246 Options exercisable – June 30, 2019 251,447 $ 6.26 8.69 $ 6,240 Options vested and expected to vest – June 30, 2019 1,454,461 $ 11.66 9.07 $ 28,246 |
Schedule of Total Stock-based Compensation Expense Related to Stock-based Awards | Total stock-based compensation expense related to all our stock-based awards was recorded in the statements of operations as follows (in thousands): Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Research and development $ 552 $ 443 $ 1,004 $ 621 General and administrative 614 176 1,126 386 Total stock-based compensation expense $ 1,166 $ 619 $ 2,130 $ 1,007 |
Employees | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
Summary of Fair Value of Employee and Non-employee Stock Options Granted | The fair value of employee and non-employee director stock option awards was estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions: Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Expected term in years 6.07 6.08 6.07 6.08 Expected volatility 72.27 % 69.76 % 72.31 % 69.59 % Risk-free interest rate 2.07 % 2.82 % 2.10 % 2.78 % Dividend yield — — — — Weighted average fair value of share-based awards granted $ 18.62 $ 7.88 $ 18.22 $ 7.50 |
Non Employees | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
Summary of Fair Value of Employee and Non-employee Stock Options Granted | The fair value of the stock options granted to non-employees was calculated at each reporting date using the Black-Scholes option-pricing model with the following assumptions: Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Expected term in years N/A 9.70 6.08 9.70 Expected volatility N/A 68.31 % 73.54 % 68.31 % Risk-free interest rate N/A 2.84 % 2.74 % 2.84 % Dividend yield N/A — — — |
Net loss per Share (Tables)
Net loss per Share (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Earnings Per Share [Abstract] | |
Schedule of Earnings Per Share | Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Numerator: Net loss attributable to common stockholders $ (14,053 ) $ (11,381 ) $ (25,786 ) $ (19,344 ) Denominator: Weighted average common shares outstanding 36,834,135 8,972,945 36,801,357 7,092,069 Weighted average unvested common shares subject to repurchase (524,395 ) (863,292 ) (558,543 ) (763,242 ) Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted 36,309,740 8,109,653 36,242,814 6,328,827 Net loss per share attributable to common stockholders $ (0.39 ) $ (1.40 ) $ (0.71 ) $ (3.06 ) |
Schedule of Shares of Potentially Dilutive Securities Excluded from Diluted Net Loss per Share Computations | The following shares of potentially dilutive securities have been excluded from the diluted net loss per share computations for the three and six months ended June 30, 2019 and 2018 because their inclusion would be anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Employee Stock Purchase Plan shares 1,475 — 1,475 — Options to purchase common stock 1,454,461 881,612 1,454,461 881,612 Common stock subject to vesting or repurchase 490,241 831,339 490,241 831,339 Total 1,946,177 1,712,951 1,946,177 1,712,951 |
Commitments and Contingencies (
Commitments and Contingencies (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Commitments And Contingencies Disclosure [Abstract] | |
Schedule of Other Information of Operating Lease | Other information related to the operating lease: Six Months Ended June 30, 2019 Cash payments over lease term (in thousands) $ 1,175 Weighted average remaining lease term (months) 41 Weighted average discount rate (1) 6 % (1) Because the rate implicit in our lease was not readily determinable, the Company used the Company’s incremental borrowing rate. In determining our incremental borrowing rate for each lease, we considered recent rates on secured borrowings, observable risk-free interest rates and credit spreads correlating to our creditworthiness, the impact of collateralization and the term of each of our lease agreements. |
Schedule of Future Minimum Lease Payments | Future minimum lease payments as of June 30, 2019 are as follows (in thousands): Operating Year Lease Commitments 2019 (remaining six months) $ 164 2020 337 2021 347 2022 327 Total 1,175 Less imputed lease interest (117 ) Total lease liabilities $ 1,058 |
Organization and Description _2
Organization and Description of Business - Additional Information (Details) $ / shares in Units, $ in Thousands | Jun. 22, 2018USD ($)$ / sharesshares | Jun. 07, 2018 | Jun. 30, 2018shares | Jun. 30, 2019USD ($)Segmentshares | Jun. 30, 2018USD ($) | Dec. 31, 2018USD ($)shares |
Organization And Description Of Business [Line Items] | ||||||
Entity date of incorporation | Aug. 6, 2013 | |||||
Entity incorporation, State | Delaware | |||||
Number of operating segment | Segment | 1 | |||||
Description of stock split | 1.196-for-1 ratio | |||||
Stock split, conversion ratio | 1.196 | |||||
Accumulated deficit | $ | $ 91,056 | $ 65,270 | ||||
Redeemable convertible preferred stock, shares outstanding | 0 | 0 | ||||
Proceeds from issuance of initial public offering, net of underwriting discounts and commissions | $ | $ 112,155 | |||||
Common Stock | ||||||
Organization And Description Of Business [Line Items] | ||||||
Number of shares issued | 7,187,500 | |||||
Proceeds from issuance of initial public offering, net of underwriting discounts and commissions | $ | $ 111,000 | |||||
Initial Public Offering | Common Stock | ||||||
Organization And Description Of Business [Line Items] | ||||||
Number of shares issued | 7,187,500 | |||||
Shares issued price per share | $ / shares | $ 17 | |||||
Redeemable convertible preferred stock and warrants converted to common stock | 24,231,517 | |||||
Overallotment Option | Common Stock | ||||||
Organization And Description Of Business [Line Items] | ||||||
Number of shares issued | 937,500 |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended | |||
Mar. 31, 2018 | Mar. 31, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | |
Accounting Policies [Abstract] | ||||||
Cash and cash equivalents | $ 131,400 | $ 176,689 | $ 157,147 | $ 5,497 | ||
Impairment of long-lived assets | $ 0 | |||||
Percentage of conversion of convertible promissory notes issued into new share of preferred stock | 70.00% | |||||
Deemed dividend related to redemption feature embedded derivative | $ 6,523 | 6,523 | ||||
Gain on extinguishment of debt | $ 7,400 | $ 7,400 |
Fair Value Measurements - Addit
Fair Value Measurements - Additional Information (Details) - USD ($) | 6 Months Ended | 12 Months Ended |
Jun. 30, 2019 | Dec. 31, 2018 | |
Fair Value Disclosures [Abstract] | ||
Fair value assets, level 1 to level 2 transfers, amount | $ 0 | $ 0 |
Fair value assets, level 2 to level 1 transfers, amount | 0 | 0 |
Fair value assets transfers into Level 3 | 0 | 0 |
Fair value assets transfers out of Level 3 | 0 | 0 |
Fair value liabilities, level 1 to level 2 transfers, amount | 0 | 0 |
Fair value liabilities, level 2 to level 1 transfers, amount | 0 | 0 |
Fair value liabilities transfers into Level 3 | 0 | 0 |
Fair value liabilities transfers out of Level 3 | $ 0 | $ 0 |
Fair Value Measurements - Sched
Fair Value Measurements - Schedule of Fair Value of Financial Assets (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Fair value of financial assets | $ 131,400 | $ 157,147 |
Level I | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Fair value of financial assets | 131,400 | 157,147 |
Money Market Funds [Member] | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Fair value of financial assets | 131,400 | 157,147 |
Money Market Funds [Member] | Level I | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Fair value of financial assets | $ 131,400 | $ 157,147 |
Fair Value Measurements - Summa
Fair Value Measurements - Summary of Embedded Derivative in Convertible Note (Details) - USD ($) $ in Thousands | 1 Months Ended | 6 Months Ended | |
Mar. 31, 2018 | Jun. 30, 2018 | Jun. 30, 2019 | |
Derivative instrument: | |||
Embedded derivative liability, valuation technique [extensible list] | us-gaap:ValuationTechniqueDiscountedCashFlowMember | ||
Embedded derivative liability, type [extensible list] | eidx:ConvertibleNoteMember | ||
Initial fair value of the embedded derivative liability issued with the Convertible Promissory Notes payable | $ 6,523 | ||
Change in fair value upon revaluation recognized in other income (expense), net | (100) | ||
Settlement of the embedded derivative liability | $ (6,500) | $ (6,423) |
Fair Value Measurements - Sum_2
Fair Value Measurements - Summary of Redeemable Convertible Preferred Stock Tranche Liability (Details) - Fair Value, Measurements, Recurring - Redeemable Convertible Preferred Stock Tranche Liability $ in Thousands | 6 Months Ended |
Jun. 30, 2018USD ($) | |
Redeemable convertible preferred stock tranche/warrant liability: | |
Issuance of Series B redeemable convertible preferred stock tranche liability | $ 64 |
Change in fair value upon revaluation recognized in other income (expense), net | 630 |
Settlement of redeemable convertible preferred stock tranche liability due to the issuance of redeemable convertible preferred stock | $ (694) |
Fair Value Measurements - Sum_3
Fair Value Measurements - Summary of Redeemable Convertible Preferred Stock Warrant Liability (Details) - Fair Value, Measurements, Recurring - Redeemable Convertible Preferred Stock Warrant Liability $ in Thousands | 6 Months Ended |
Jun. 30, 2018USD ($) | |
Redeemable convertible preferred stock tranche/warrant liability: | |
Issuance of redeemable convertible preferred stock warrant liability | $ 878 |
Change in fair value upon revaluation recognized in other income (expense), net | 2,628 |
Reclassification of redeemable convertible preferred stock warrant liability to common stock at closing of initial public offering | $ (3,506) |
Condensed Balance Sheet Compo_3
Condensed Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Property Plant And Equipment [Line Items] | ||
Total Property and equipment, cost | $ 292 | $ 269 |
Less: Accumulated depreciation and amortization | (88) | (60) |
Total property and equipment, net | 204 | 209 |
Leasehold Improvements | ||
Property Plant And Equipment [Line Items] | ||
Total Property and equipment, cost | 86 | 86 |
Computer Equipment | ||
Property Plant And Equipment [Line Items] | ||
Total Property and equipment, cost | 110 | 87 |
Office Furniture and Equipment | ||
Property Plant And Equipment [Line Items] | ||
Total Property and equipment, cost | $ 96 | $ 96 |
Condensed Balance Sheet Compo_4
Condensed Balance Sheet Components - Additional Information (Details) - USD ($) | 3 Months Ended | 6 Months Ended | |||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | |
Condensed Balance Sheet Components [Line Items] | |||||
Depreciation and amortization | $ 18,000 | $ 14,000 | $ 33,000 | $ 24,000 | |
Other Liabilities | |||||
Condensed Balance Sheet Components [Line Items] | |||||
Other liabilities related to long-term liability for unvested stock | $ 164,000 | $ 164,000 | $ 244,000 |
Condensed Balance Sheet Compo_5
Condensed Balance Sheet Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Accrued Liabilities And Other Liabilities [Abstract] | ||
Accrued research and development costs | $ 2,602 | $ 2,055 |
Accrued employee related expenses | 1,102 | 78 |
Liability for unvested stock, short-term | 147 | 142 |
Accrued other current liabilities | 176 | 302 |
Total accrued expenses and other current liabilities | $ 4,027 | $ 2,577 |
Condensed Balance Sheet Compo_6
Condensed Balance Sheet Components - Schedule of Lease Liabilities (Details) $ in Thousands | Jun. 30, 2019USD ($) |
Balance Sheet Related Disclosures [Abstract] | |
Lease liabilities | $ 276 |
Lease liabilities, non-current | 782 |
Total lease liabilities | $ 1,058 |
Convertible Promissory Notes -
Convertible Promissory Notes - Additional Information (Details) | 1 Months Ended | 3 Months Ended | 6 Months Ended | ||
Mar. 31, 2018USD ($)shares$ / shares | Feb. 28, 2018USD ($)ConvertiblePromissoryNote$ / shares | Jun. 30, 2018USD ($) | Jun. 30, 2019 | Jun. 30, 2018USD ($) | |
Short Term Debt [Line Items] | |||||
Gain on extinguishment of debt | $ 7,400,000 | $ 7,400,000 | |||
Fair value of embedded derivative liability settled | 6,500,000 | 6,423,000 | |||
Extinguishment of Debt, Amount | $ 14,400,000 | ||||
Expense related to warrants | $ 2,600 | 2,600 | |||
Series B Redeemable Convertible Preferred Stock | |||||
Short Term Debt [Line Items] | |||||
Warrant exercise price per share | $ / shares | $ 10.8348 | ||||
Debt instrument, converted into number of shares | shares | 1,324,823 | ||||
Debt instrument conversion price | $ / shares | $ 7.5844 | ||||
Proceeds from Issuance of redeemable preferred stock | $ 14,400,000 | ||||
Warrants to purchase shares | shares | 369,180 | ||||
Series B Redeemable Convertible Preferred Stock | Initial Public Offering | |||||
Short Term Debt [Line Items] | |||||
Warrants to purchase shares | shares | 206,247 | ||||
Convertible Promissory Notes | |||||
Short Term Debt [Line Items] | |||||
Outstanding principal and accrued interest | $ 10,000,000 | ||||
Note and Warrant Purchase Agreement | BBP LLC and Stanford University | |||||
Short Term Debt [Line Items] | |||||
Number of convertible promissory notes issued | ConvertiblePromissoryNote | 2 | ||||
Aggregate principal amount | $ 10,000,000 | ||||
Debt instrument, maturity date description | The Convertible Promissory Notes had a maturity date of the earliest of a qualified financing, a deemed liquidation event, a qualified initial public offering, or February 2019 | ||||
Debt instrument, maturity month and year | 2019-02 | ||||
Debt instrument, annual interest rate | 5.00% | ||||
Debt instrument, convertible discount percentage | 30.00% | ||||
Note and Warrant Purchase Agreement | BBP LLC and Stanford University | Series Seed Redeemable Convertible Preferred Stock | |||||
Short Term Debt [Line Items] | |||||
Warrants issued upon purchase of preferred stock under equity financing | $ 4,000,000 | ||||
Warrant exercise price per share | $ / shares | $ 1.3248 | ||||
Note and Warrant Purchase Agreement | BBP LLC and Stanford University | Minimum | |||||
Short Term Debt [Line Items] | |||||
Debt instrument convertible into future preferred stock under preferred equity financing | $ 10,000,000 | ||||
Debt instrument convertible into common stock under initial public offering | 30,000,000 | ||||
Note and Warrant Purchase Agreement | BBP LLC and Stanford University | Convertible Promissory Notes | |||||
Short Term Debt [Line Items] | |||||
Fair value of warrants recorded as debt discount and redeemable convertible preferred stock warrant liability | 900,000 | ||||
Debt instrument, beneficial conversion feature | 9,100,000 | ||||
Interest Expense | $ 0 | $ 1,000,000 | |||
Fair value of embedded derivative liability | $ 6,500,000 |
Related Party Transactions - Ad
Related Party Transactions - Additional Information (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 6 Months Ended | |||||
May 31, 2018 | Aug. 31, 2016 | Apr. 30, 2016 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | |
2018 Plan | Dr. Huh | ||||||||
Related Party Transaction [Line Items] | ||||||||
Number of options granted | 83,720 | |||||||
Option vesting period | 3 years | |||||||
Stock - based compensation expense related to awards | $ 0 | $ 13,000 | $ 0 | $ 13,000 | ||||
Dr. Graef Consulting Agreement | ||||||||
Related Party Transaction [Line Items] | ||||||||
Consulting agreement term | 4 years | |||||||
Consulting agreement termination notice period | 30 days | |||||||
Dr. Graef Consulting Agreement | Maximum | ||||||||
Related Party Transaction [Line Items] | ||||||||
Annual fee amount | $ 150,000 | |||||||
Dr. Alhamadsheh Consulting Agreement | ||||||||
Related Party Transaction [Line Items] | ||||||||
Consulting agreement term | 4 years | |||||||
Consulting agreement termination notice period | 30 days | |||||||
Dr. Alhamadsheh Consulting Agreement | Maximum | ||||||||
Related Party Transaction [Line Items] | ||||||||
Annual fee amount | $ 115,000 | |||||||
BridgeBio Pharma LLC | ||||||||
Related Party Transaction [Line Items] | ||||||||
Outstanding receivable | 200,000 | 200,000 | $ 34,000 | |||||
Outstanding liability | $ 300,000 | $ 300,000 | $ 300,000 | |||||
BridgeBio Pharma LLC | ||||||||
Related Party Transaction [Line Items] | ||||||||
Ownership percentage | 64.00% | 64.00% | 61.00% |
Related Party Transactions - Sc
Related Party Transactions - Schedule of Expenses under the Agreement (Details) - BridgeBio Pharma LLC - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Related Party Transaction [Line Items] | ||||
Related party transaction expenses | $ 44 | $ 438 | $ 217 | $ 778 |
Rent | ||||
Related Party Transaction [Line Items] | ||||
Related party transaction expenses | (8) | 11 | (11) | 19 |
Facility | ||||
Related Party Transaction [Line Items] | ||||
Related party transaction expenses | (4) | 57 | 75 | 102 |
Consulting | ||||
Related Party Transaction [Line Items] | ||||
Related party transaction expenses | $ 56 | $ 370 | $ 153 | $ 657 |
Related Party Transactions - _2
Related Party Transactions - Schedule of Expenses (Benefit) for Services under Consulting Agreements and Stock-Based Compensation (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Dr. Graef | ||||
Related Party Transaction [Line Items] | ||||
Related party transaction expenses (benefit) | $ 38 | $ 38 | $ 76 | $ 76 |
Dr. Alhamadsheh | ||||
Related Party Transaction [Line Items] | ||||
Related party transaction expenses (benefit) | 29 | 29 | 58 | 58 |
Founders | ||||
Related Party Transaction [Line Items] | ||||
Related party transaction expenses (benefit) | $ 67 | $ 67 | $ 134 | $ 134 |
Redeemable Convertible Prefer_3
Redeemable Convertible Preferred Stock - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | Mar. 29, 2018 | May 31, 2018 | Mar. 31, 2018 | Jun. 30, 2018 | Jun. 30, 2018 | Jun. 30, 2019 | Dec. 31, 2018 | Jun. 22, 2018 | Dec. 31, 2017 |
Temporary Equity [Line Items] | |||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 63,875 | ||||||||
Financial liabilities, fair value | $ 700 | ||||||||
Number of common stock issued upon conversion of redeemable convertible preferred stock | 24,025,270 | ||||||||
Redeemable convertible preferred stock, shares outstanding | 0 | 0 | |||||||
Series B Redeemable Convertible Preferred Stock | |||||||||
Temporary Equity [Line Items] | |||||||||
Redeemable convertible preferred stock issued | 4,430,162 | 1,476,715 | 4,430,162 | ||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 16,000 | $ 48,000 | $ 16,000 | ||||||
Additional redeemable convertible preferred stock issuable | 4,430,162 | ||||||||
Financial liabilities, fair value | $ 700 | $ 100 | |||||||
Redeemable convertible preferred stock purchase price per share | $ 10.8348 | $ 10.8348 | |||||||
Redeemable convertible preferred stock, shares outstanding | 15,657,863 | 12,856,325 |
Redeemable Convertible Prefer_4
Redeemable Convertible Preferred Stock Tranche Liability - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | Mar. 29, 2018 | May 31, 2018 | Mar. 31, 2018 | Jun. 30, 2018 | Jun. 30, 2018 |
Temporary Equity [Line Items] | |||||
Proceeds from issuance of redeemable convertible preferred stock | $ 63,875 | ||||
Shares issued upon conversion of outstanding convertible promissory note | 1,324,823 | ||||
Conversion of convertible promissory note principal balance | $ 10,000 | ||||
Financial liabilities, fair value | $ 700 | ||||
Series B Redeemable Convertible Preferred Stock | |||||
Temporary Equity [Line Items] | |||||
Redeemable convertible preferred stock issued | 4,430,162 | 1,476,715 | 4,430,162 | ||
Redeemable convertible preferred stock purchase price per share | $ 10.8348 | $ 10.8348 | |||
Proceeds from issuance of redeemable convertible preferred stock | $ 16,000 | $ 48,000 | $ 16,000 | ||
Additional shares issuable upon achievement of certain milestone | 4,430,162 | ||||
Financial liabilities, fair value | $ 700 | $ 100 | |||
Series B Redeemable Convertible Preferred Stock | Maximum | |||||
Temporary Equity [Line Items] | |||||
Redeemable convertible preferred stock issued | 1,476,715 | 7,231,700 | |||
Series B Preferred Stock | |||||
Temporary Equity [Line Items] | |||||
Conversion of convertible promissory note principal balance | $ 14,400 | ||||
Financial liabilities, fair value | $ 100 |
Stockholders' Equity and Stoc_3
Stockholders' Equity and Stock-Based Compensation - Summary of Reserved Shares of Common Stock for Issuance (Details) - shares | Jun. 30, 2019 | Jun. 30, 2018 |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Common stock reserved for issuance | 2,096,346 | 1,515,492 |
Options Issued and Outstanding | ||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Common stock reserved for issuance | 1,454,461 | 881,612 |
Options Available for Future Grants | ||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Common stock reserved for issuance | 537,345 | 490,360 |
Employee Stock Purchase Plan Shares Available for Future Grants | ||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Common stock reserved for issuance | 104,540 | 143,520 |
Stockholders' Equity and Stoc_4
Stockholders' Equity and Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands | 6 Months Ended | 12 Months Ended |
Jun. 30, 2019USD ($)$ / sharesshares | Dec. 31, 2018USD ($)$ / sharesshares | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Options Available for Grant, Outstanding, Beginning balance | 747,057 | |
Options Available for Grant, Outstanding, Ending balance | 537,345 | 747,057 |
Options Outstanding, Beginning balance | 1,329,762 | |
Options Outstanding, Options exercised | (85,013) | |
Options Outstanding, Ending balance | 1,454,461 | 1,329,762 |
Options Outstanding, Options exercisable | 251,447 | |
Options Outstanding, Options vested and expected to vest | 1,454,461 | |
Weighted-Average Exercise Price Per Share, Beginning balance | $ / shares | $ 8.55 | |
Weighted-Average Exercise Price Per Share, Options Exercised | $ / shares | 1.32 | |
Weighted-Average Exercise Price Per Share, Ending balance | $ / shares | 11.66 | $ 8.55 |
Weighted-Average Exercise Price Per Share, Options exercisable | $ / shares | 6.26 | |
Weighted-Average Exercise Price Per Share, Options vested and expected to vest | $ / shares | $ 11.66 | |
Weighted-Average Remaining Contractual Term (years), Outstanding | 9 years 25 days | 9 years 4 months 24 days |
Weighted-Average Remaining Contractual Term (years), Options exercisable | 8 years 8 months 8 days | |
Weighted-Average Remaining Contractual Term (years), Options vested and expected to vest | 9 years 25 days | |
Aggregate Intrinsic Value, Outstanding, Beginning balance | $ | $ 6,928 | |
Aggregate Intrinsic Value, Outstanding, Ending balance | $ | 28,246 | $ 6,928 |
Aggregate Intrinsic Value, Options exercisable | $ | 6,240 | |
Aggregate Intrinsic Value, Options vested and expected to vest | $ | $ 28,246 | |
2016 Equity Incentive Plan | ||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Options Available for Grant, Options granted | (209,712) | |
Options Outstanding, Options granted | 209,712 | |
Weighted-Average Exercise Price Per Share, Options granted | $ / shares | $ 27.22 |
Stockholders' Equity and Stoc_5
Stockholders' Equity and Stock-Based Compensation - Summary of Fair Value of Employee and Non-employee Stock Options Granted (Details) - $ / shares | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Options Available for Future Grants | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Expected term in years | 6 years 25 days | 6 years 29 days | 6 years 25 days | 6 years 29 days |
Expected volatility | 72.27% | 69.76% | 72.31% | 69.59% |
Risk-free interest rate | 2.07% | 2.82% | 2.10% | 2.78% |
Weighted average fair value of share-based awards granted | $ 18.62 | $ 7.88 | $ 18.22 | $ 7.50 |
Non Employees | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Expected term in years | 9 years 8 months 12 days | 6 years 29 days | 9 years 8 months 12 days | |
Expected volatility | 68.31% | 73.54% | 68.31% | |
Risk-free interest rate | 2.84% | 2.74% | 2.84% |
Stockholders' Equity and Stoc_6
Stockholders' Equity and Stock-Based Compensation - Additional Information (Details) - USD ($) | 3 Months Ended | 6 Months Ended | |||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Stock-based compensation expense | $ 1,166,000 | $ 619,000 | $ 2,130,000 | $ 1,007,000 | |
Stock repurchase right | 709,927 | 709,927 | 896,034 | ||
Accrued repurchase liability for common stock early exercises | $ 311,000 | $ 311,000 | $ 386,000 | ||
2016 and 2018 Plans | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Unrecognized stock-based compensation cost related to unvested stock | $ 12,500,000 | $ 12,500,000 | |||
Unrecognized stock-based compensation cost, to be recognized weighted-average period | 2 years 7 months 28 days | ||||
Non Employees | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Options Outstanding, Options granted | 0 | 35,880 | 18,500 | 35,880 | |
Stock-based compensation expense | $ 100,000 | $ 100,000 | $ 100,000 | $ 200,000 |
Stockholders' Equity and Stoc_7
Stockholders' Equity and Stock-Based Compensation - Schedule of Total Stock-based Compensation Expense Related to Stock-based Awards (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
Stock-based compensation expense | $ 1,166 | $ 619 | $ 2,130 | $ 1,007 |
Research and Development | ||||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
Stock-based compensation expense | 552 | 443 | 1,004 | 621 |
General and Administrative | ||||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
Stock-based compensation expense | $ 614 | $ 176 | $ 1,126 | $ 386 |
Net loss per Share - Schedule o
Net loss per Share - Schedule of Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Numerator: | ||||
Net loss attributable to common stockholders | $ (14,053) | $ (11,381) | $ (25,786) | $ (19,344) |
Denominator: | ||||
Weighted average common shares outstanding | 36,834,135 | 8,972,945 | 36,801,357 | 7,092,069 |
Weighted average unvested common shares subject to repurchase | (524,395) | (863,292) | (558,543) | (763,242) |
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted | 36,309,740 | 8,109,653 | 36,242,814 | 6,328,827 |
Net loss per share attributable to common stockholders, basic and diluted | $ (0.39) | $ (1.40) | $ (0.71) | $ (3.06) |
Net loss per Share - Schedule_2
Net loss per Share - Schedule of Shares of Potentially Dilutive Securities Excluded from Diluted Net Loss per Share Computations (Detail) - shares | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||||
Antidilutive securities excluded from calculation of net loss per share | 1,946,177 | 1,712,951 | 1,946,177 | 1,712,951 |
Employee Stock Purchase Plan Shares | ||||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||||
Antidilutive securities excluded from calculation of net loss per share | 1,475 | 1,475 | ||
Options to Purchase Common Stock | ||||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||||
Antidilutive securities excluded from calculation of net loss per share | 1,454,461 | 881,612 | 1,454,461 | 881,612 |
Common Stock Subject to Vesting or Repurchase | ||||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||||
Antidilutive securities excluded from calculation of net loss per share | 490,241 | 831,339 | 490,241 | 831,339 |
Stanford License Agreement - Ad
Stanford License Agreement - Additional Information (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended | ||||
Feb. 28, 2019 | Mar. 31, 2018 | Apr. 30, 2016 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2017 | |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||||
Research and development expense | $ 12,497,000 | $ 6,195,000 | $ 21,046,000 | $ 11,847,000 | ||||
License Agreement | Stanford University | ||||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||||
Upfront license payment amount | $ 25,000 | |||||||
Maximum potential payments upon achievement of specific intellectual property, clinical and regulatory milestone events and royalties payment on net sales | $ 1,000,000 | |||||||
Period of annual decrease in license obligation amount due | 3 years | |||||||
Research and development expense | $ 200,000 | $ 50,000 | $ 0 | $ 0 | $ 200,000 | $ 100,000 | ||
License Agreement | Stanford University | Common Stock | ||||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||||
Shares issued | 56,809 | |||||||
Research and Development | License Agreement | Stanford University | ||||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||||
License fee paid | $ 10,000 |
Commitments and Contingencies -
Commitments and Contingencies - Additional Information (Details) | Mar. 27, 2019USD ($)ft² | Jun. 30, 2019USD ($) | Jun. 30, 2018USD ($) | Jun. 30, 2019USD ($) | Jun. 30, 2018USD ($) | Jan. 01, 2019USD ($) | Sep. 30, 2017 |
Commitments And Contingencies [Line Items] | |||||||
Lease liability | $ 1,100,000 | $ 1,100,000 | $ 1,200,000 | ||||
Operating lease, right of use asset | 988,000 | 988,000 | $ 1,100,000 | ||||
Rent expense | 100,000 | $ 100,000 | $ 200,000 | $ 200,000 | |||
Administrative Facility | San Francisco, California | |||||||
Commitments And Contingencies [Line Items] | |||||||
Operating lease, expiration period | 2022-11 | ||||||
Lease amendment date | Mar. 27, 2019 | ||||||
Rentable square feet to be leased | ft² | 10,552 | ||||||
Amended lease term | 87 months | ||||||
Lease payments | $ 6,400,000 | ||||||
Laboratory Facilities | San Francisco, California | |||||||
Commitments And Contingencies [Line Items] | |||||||
Operating lease, term of contract | 1 year | ||||||
Other Assets | San Francisco, California | |||||||
Commitments And Contingencies [Line Items] | |||||||
Security deposit for lease | $ 158,000 | $ 158,000 |
Commitments and Contingencies_2
Commitments and Contingencies - Schedule of Other Information of Operating Lease (Details) $ in Thousands | 6 Months Ended | |
Jun. 30, 2019USD ($) | ||
Commitments And Contingencies Disclosure [Abstract] | ||
Cash payments over lease term (in thousands) | $ 1,175 | |
Weighted average remaining lease term (months) | 41 months | |
Weighted average discount rate | 6.00% | [1] |
[1] | Because the rate implicit in our lease was not readily determinable, the Company used the Company’s incremental borrowing rate. In determining our incremental borrowing rate for each lease, we considered recent rates on secured borrowings, observable risk-free interest rates and credit spreads correlating to our creditworthiness, the impact of collateralization and the term of each of our lease agreements. |
Commitments and Contingencies_3
Commitments and Contingencies - Schedule of Future Minimum Lease Payments (Details) $ in Thousands | Jun. 30, 2019USD ($) |
Commitments And Contingencies Disclosure [Abstract] | |
2019 (remaining six months) | $ 164 |
2020 | 337 |
2021 | 347 |
2022 | 327 |
Total | 1,175 |
Less imputed lease interest | (117) |
Total lease liabilities | $ 1,058 |
Income Taxes - Additional Infor
Income Taxes - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Income Tax Disclosure [Abstract] | ||||
Effective income tax Rate reconciliation, at federal statutory income tax rate, percent | 21.00% | 21.00% | 21.00% | 21.00% |
Net tax expense | $ 0 | $ 0 | $ 0 | $ 0 |