Document and Entity Information
Document and Entity Information - USD ($) $ in Millions | 12 Months Ended | ||
Dec. 31, 2019 | Feb. 24, 2020 | Jun. 30, 2019 | |
Cover [Abstract] | |||
Document Type | 10-K | ||
Amendment Flag | false | ||
Document Period End Date | Dec. 31, 2019 | ||
Document Fiscal Year Focus | 2019 | ||
Document Fiscal Period Focus | FY | ||
Trading Symbol | EIDX | ||
Entity Registrant Name | EIDOS THERAPEUTICS, INC. | ||
Entity Central Index Key | 0001731831 | ||
Current Fiscal Year End Date | --12-31 | ||
Entity Well-known Seasoned Issuer | No | ||
Entity Current Reporting Status | Yes | ||
Entity Voluntary Filers | No | ||
Entity Filer Category | Accelerated Filer | ||
Entity Small Business | true | ||
Entity Emerging Growth Company | true | ||
Entity Ex Transition Period | true | ||
Entity Shell Company | false | ||
Entity Common Stock, Shares Outstanding | 38,509,861 | ||
Entity Public Float | $ 280.1 | ||
Entity File Number | 001-38533 | ||
Entity Tax Identification Number | 46-3733671 | ||
Entity Address, Address Line One | 101 Montgomery Street | ||
Entity Address, Address Line Two | Suite 2000 | ||
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 | ||
Entity Interactive Data Current | Yes | ||
Title of 12(b) Security | Common Stock, par value $0.001 per share | ||
Security Exchange Name | NASDAQ | ||
Entity Incorporation, State or Country Code | DE | ||
Document Annual Report | true | ||
Document Transition Report | false | ||
Documents Incorporated by Reference | DOCUMENTS INCORPORATED BY REFERENCE: Portions of the Registrant’s definitive Proxy Statement for the Registrant’s 2020 Annual Meeting of Stockholders, to be filed subsequent to the date hereof with the Securities and Exchange Commission (SEC), are incorporated by reference into Part III of this report. Such proxy statement will be filed with the SEC not later than 120 days after the end of the Registrant’s fiscal year ended December 31, 2019. |
Balance Sheets
Balance Sheets - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Current assets: | ||
Cash and cash equivalents | $ 191,157 | $ 157,147 |
Related party receivable | 85 | 34 |
Prepaid expenses and other current assets | 4,678 | 1,789 |
Total current assets | 195,920 | 158,970 |
Property and equipment, net | 1,259 | 209 |
Operating Lease, right of use asset | 4,010 | |
Other assets | 2,631 | 933 |
Total assets | 203,820 | 160,112 |
Current liabilities: | ||
Accounts payable | 3,151 | 1,956 |
Related party payable | 316 | 256 |
Accrued expenses and other current liabilities | 6,409 | 2,577 |
Lease liabilities | 554 | |
Total current liabilities | 10,430 | 4,789 |
Debt, non-current | 16,112 | |
Lease liabilities, non-current | 4,591 | |
Embedded derivative | 1,165 | |
Other liabilities | 95 | 316 |
Total liabilities | 32,393 | 5,105 |
Commitments and contingencies | ||
Stockholders’ equity: | ||
Preferred stock, $0.001 par value, 5,000,000 shares authorized as of December 31, 2019 and December 31, 2018, respectively; and no shares issued and outstanding as of December 31, 2019 and December 31, 2018, respectively; | ||
Common stock, $0.001 par value; 150,000,000 shares authorized as of December 31, 2019 and December 31, 2018, respectively; 38,040,693 and 36,760,536 shares issued and outstanding as of December 31, 2019 and December 31, 2018, respectively; | 38 | 37 |
Additional paid-in capital | 274,494 | 220,240 |
Accumulated deficit | (103,105) | (65,270) |
Total stockholders’ equity | 171,427 | 155,007 |
Total liabilities and stockholders’ equity | $ 203,820 | $ 160,112 |
Balance Sheets (Parenthetical)
Balance Sheets (Parenthetical) - $ / shares | Dec. 31, 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 | 38,040,693 | 36,760,536 |
Common stock, shares outstanding | 38,040,693 | 36,760,536 |
Statements of Operations and Co
Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Income Statement [Abstract] | |||
License revenue | $ 26,691 | ||
Cost, Product and Service [Extensible List] | us-gaap:LicenseMember | us-gaap:LicenseMember | us-gaap:LicenseMember |
Operating costs and expenses: | |||
Cost of license revenue | $ 2,500 | ||
Cost, Product and Service [Extensible List] | us-gaap:LicenseMember | us-gaap:LicenseMember | us-gaap:LicenseMember |
Research and development (includes related party (benefit) expense of ($278), ($66) and $118, respectively) | $ 46,891 | $ 28,539 | $ 9,286 |
General and administrative (includes related party expense of $797, $1,225, and $679, respectively) | 17,751 | 9,240 | 2,730 |
Total operating expenses | 67,142 | 37,779 | 12,016 |
Loss from operations | (40,451) | (37,779) | (12,016) |
Interest expense | (327) | (1,011) | |
Other income (expense), net | 2,943 | (1,935) | 75 |
Net and comprehensive loss | (37,835) | (40,725) | (11,941) |
Deemed dividend related to redemption feature embedded in Convertible Promissory Notes payable to stockholders | (6,500) | (6,523) | |
Gain on extinguishment of Convertible Promissory Notes payable to stockholders | 7,436 | ||
Net loss attributable to common stockholders | $ (37,835) | $ (39,812) | $ (11,941) |
Net loss per share attributable to common stockholders | $ (1.03) | $ (1.86) | $ (3.32) |
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted | 36,624,692 | 21,366,995 | 3,596,673 |
Statements of Operations and _2
Statements of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Income Statement [Abstract] | |||
Research and development (benefit) expense included from related party | $ (278) | $ (66) | $ 118 |
General and administrative expense included from related party | $ 797 | $ 1,225 | $ 679 |
Statements of Redeemable Conver
Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands | Total | Consultant | Stanford University | Alexion Pharmaceuticals, Inc. | Open Market Sale Agreement | Common Stock | Common StockConsultant | Common StockStanford University | Common StockAlexion Pharmaceuticals, Inc. | Common StockOpen Market Sale Agreement | Additional Paid in Capital | Additional Paid in CapitalConsultant | Additional Paid in CapitalStanford University | Additional Paid in CapitalAlexion Pharmaceuticals, Inc. | Additional Paid in CapitalOpen Market Sale Agreement | Accumulated Deficit | Series Seed Redeemable Convertible Preferred Stock | Series B Redeemable Convertible Preferred Stock |
Balance at Dec. 31, 2016 | $ (2,473) | $ 3 | $ 115 | $ (2,591) | ||||||||||||||
Balance, Shares at Dec. 31, 2016 | 4,059,515 | |||||||||||||||||
Redeemable convertible preferred stock, Balance at Dec. 31, 2016 | $ 3,795 | |||||||||||||||||
Redeemable convertible preferred stock, Balance, Shares at Dec. 31, 2016 | 3,043,525 | |||||||||||||||||
Issuance of redeemable convertible preferred stock, net of issuance costs | $ 12,993 | |||||||||||||||||
Issuance of redeemable convertible preferred stock, net of issuance costs, Shares | 9,812,800 | |||||||||||||||||
Settlement of fair value of redeemable convertible preferred stock tranche liability | $ 240 | |||||||||||||||||
Issuance of common stock for services and technology | $ 5 | $ 5 | ||||||||||||||||
Issuance of common stock for services and technology, Shares | 35,880 | |||||||||||||||||
Issuance of restricted common stock to founders in connection with anti-dilution rights, Shares | 390,546 | |||||||||||||||||
Issuance of common stock upon exercise of stock options and restricted stock | 27 | $ 1 | 26 | |||||||||||||||
Issuance of common stock upon exercise of stock options and restricted stock, Shares | 651,830 | |||||||||||||||||
Vesting of restricted stock and early exercised options | 38 | 38 | ||||||||||||||||
Stock-based compensation expense | 1,148 | 1,148 | ||||||||||||||||
Net loss and comprehensive loss | (11,941) | (11,941) | ||||||||||||||||
Balance at Dec. 31, 2017 | (13,196) | $ 4 | 1,332 | (14,532) | ||||||||||||||
Balance, Shares at Dec. 31, 2017 | 5,137,771 | |||||||||||||||||
Redeemable convertible preferred stock, Balance at Dec. 31, 2017 | $ 17,028 | |||||||||||||||||
Redeemable convertible preferred stock, Balance, Shares at Dec. 31, 2017 | 12,856,325 | 12,856,325 | ||||||||||||||||
Issuance of redeemable convertible preferred stock, net of issuance costs and tranche liability | $ 15,811 | |||||||||||||||||
Issuance of redeemable convertible preferred stock, net of issuance costs and tranche liability, Shares | 1,476,715 | |||||||||||||||||
Issuance of common stock under employee stock plans | $ 160 | 160 | ||||||||||||||||
Issuance of common stock under employee stock plans, Shares | 13,354 | |||||||||||||||||
Reacquisition of beneficial conversion feature related to convertible promissory notes payable to stockholders | (14,354) | (4,341) | (10,013) | |||||||||||||||
Gain on extinguishment of Convertible Promissory Notes payable to stockholders | 7,436 | 7,436 | ||||||||||||||||
Issuance of redeemable convertible preferred stock, net of issuance costs | $ 48,000 | |||||||||||||||||
Issuance of redeemable convertible preferred stock, net of issuance costs, Shares | 4,430,162 | |||||||||||||||||
Issuance of redeemable convertible preferred stock upon conversion of redeemable convertible notes payable and accrued interest | $ 14,354 | |||||||||||||||||
Issuance of redeemable convertible preferred stock upon conversion of redeemable convertible notes payable and accrued interest, Shares | 1,324,823 | |||||||||||||||||
Settlement of fair value of redeemable convertible preferred stock tranche liability | $ 694 | |||||||||||||||||
Recognition of beneficial conversion feature related to convertible promissory notes payable to stockholders | 9,122 | 9,122 | ||||||||||||||||
Deemed dividend related to redemption feature embedded in Convertible Promissory Notes payable to stockholders | (6,523) | (6,523) | ||||||||||||||||
Issuance of common stock for services and technology | $ 7 | $ 7 | ||||||||||||||||
Issuance of common stock for services and technology, Shares | 45,889 | |||||||||||||||||
Issuance of common stock upon exercise of stock options and restricted stock | 21 | 21 | ||||||||||||||||
Issuance of common stock upon exercise of stock options and restricted stock, Shares | 184,871 | |||||||||||||||||
Net exercise of redeemable convertible preferred stock warrant liability | 3,506 | 3,506 | ||||||||||||||||
Net exercise of redeemable convertible preferred stock warrant liability, Shares | 206,247 | |||||||||||||||||
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering | 95,887 | $ 25 | 95,862 | |||||||||||||||
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering, Shares | 24,025,270 | |||||||||||||||||
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering | $ (95,887) | |||||||||||||||||
Conversion of redeemable convertible preferred stock to common stock at closing of initial public offering, Shares | (20,088,025) | |||||||||||||||||
Issuance of common stock upon initial public offering, net of issuance costs | $ 110,970 | $ 8 | 110,962 | |||||||||||||||
Issuance of common stock upon initial public offering, net of issuance costs, Shares | 7,187,500 | |||||||||||||||||
Repurchase of early exercised stock options, Shares | (40,366) | |||||||||||||||||
Vesting of restricted stock and early exercised options | 170 | 170 | ||||||||||||||||
Stock-based compensation expense | 2,526 | 2,526 | ||||||||||||||||
Net loss and comprehensive loss | (40,725) | (40,725) | ||||||||||||||||
Balance at Dec. 31, 2018 | 155,007 | $ 37 | 220,240 | (65,270) | ||||||||||||||
Balance, Shares at Dec. 31, 2018 | 36,760,536 | |||||||||||||||||
Issuance of common stock under employee stock plans | 487 | 487 | ||||||||||||||||
Issuance of common stock under employee stock plans, Shares | 32,361 | |||||||||||||||||
Deemed dividend related to redemption feature embedded in Convertible Promissory Notes payable to stockholders | (6,500) | |||||||||||||||||
Issuance of common stock upon exercise of stock options and restricted stock | $ 1,010 | 1,010 | ||||||||||||||||
Issuance of common stock upon exercise of stock options and restricted stock, Shares | 306,010 | 306,010 | ||||||||||||||||
Issuance of common stock upon initial public offering, net of issuance costs | $ 23,309 | $ 23,927 | $ 1 | $ 23,308 | $ 23,927 | |||||||||||||
Issuance of common stock upon initial public offering, net of issuance costs, Shares | 556,173 | 385,613 | ||||||||||||||||
Vesting of restricted stock and early exercised options | $ 149 | 149 | ||||||||||||||||
Stock-based compensation expense | 5,373 | 5,373 | ||||||||||||||||
Net loss and comprehensive loss | (37,835) | (37,835) | ||||||||||||||||
Balance at Dec. 31, 2019 | $ 171,427 | $ 38 | $ 274,494 | $ (103,105) | ||||||||||||||
Balance, Shares at Dec. 31, 2019 | 38,040,693 | |||||||||||||||||
Redeemable convertible preferred stock, Balance, Shares at Dec. 31, 2019 | 0 |
Statements of Redeemable Conv_2
Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Open Market Sale Agreement | |||
Issuance costs | $ 48 | ||
Series Seed Redeemable Convertible Preferred Stock | |||
Issuance costs | $ 7 | ||
Series B Redeemable Convertible Preferred Stock | |||
Issuance costs | $ 125 | ||
Issuance costs for additional redeemable convertible preferred stock | 0 | ||
Redeemable convertible preferred stock tranche liability | $ 64 |
Statements of Cash Flows
Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Cash Flows From Operating Activities: | |||
Net loss | $ (37,835) | $ (40,725) | $ (11,941) |
Adjustments to reconcile net loss to net cash used in operating activities: | |||
Depreciation and amortization | 77 | 56 | 4 |
Stock-based compensation expense | 5,373 | 2,526 | 1,148 |
Accrued interest on Convertible Promissory Notes payable | 48 | ||
Change in fair value of derivative liability | 17 | (100) | |
Change in fair value of redeemable convertible preferred stock tranche liabilities | 630 | (75) | |
Change in fair value of redeemable convertible preferred stock warrant liability | 2,628 | ||
Issuance of common stock in exchange for services and technology | 7 | 5 | |
Amortization of debt discount | 108 | 963 | |
Loss on disposal of asset | 59 | ||
Gain on extinguishment of leasehold liability | (69) | ||
Changes in assets and liabilities: | |||
Related party receivable | (51) | 33 | (62) |
Prepaid expenses and other current assets | (2,889) | (1,305) | (477) |
Other assets | (5,708) | (752) | (174) |
Accounts payable | 1,195 | 1,390 | 472 |
Accrued expenses and other liabilities | 8,015 | 1,416 | 1,070 |
Related party payable | 60 | (116) | 313 |
Net cash used in operating activities | (31,648) | (33,301) | (9,717) |
Cash Flows From Investing Activities: | |||
Purchases of property and equipment | (227) | (150) | (53) |
Net cash used in investing activities | (227) | (150) | (53) |
Cash Flows From Financing Activities: | |||
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs | 63,875 | 12,993 | |
Proceeds from long-term debt, net of debt discount and issuance costs | 17,500 | ||
Payment of deferred financing costs | (348) | ||
Proceeds from issuance of Convertible Promissory Notes payable | 10,000 | ||
Proceeds from issuance of common stock under employee stock plan | 487 | 160 | |
Proceeds from issuance of common stock upon exercise of stock options and restricted stock | 1,010 | 96 | 318 |
Proceeds from issuance of common stock in initial public offering, net of issuance costs | 110,970 | ||
Net cash provided by financing activities | 65,885 | 185,101 | 13,311 |
Net increase in cash and cash equivalents | 34,010 | 151,650 | 3,541 |
Cash and cash equivalents, beginning of period | 157,147 | 5,497 | 1,956 |
Cash and cash equivalents, end of period | 191,157 | 157,147 | 5,497 |
Other supplemental information: | |||
Interest paid | 74 | ||
Supplemental disclosure of non-cash activities: | |||
Settlement of redeemable convertible preferred stock tranche liability through issuance of preferred stock | 694 | 240 | |
Lease liability arising from the right of use asset | 5,155 | ||
Vesting of restricted stock and early exercised options | 149 | 170 | $ 38 |
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 | ||
Embedded derivative liability | 1,147 | ||
Tenant improvements paid by landlord | 959 | ||
Open Market Sale Agreement | |||
Cash Flows From Financing Activities: | |||
Proceeds from the issuance of common stock | 23,927 | ||
Alexion | |||
Cash Flows From Financing Activities: | |||
Proceeds from the issuance of common stock | $ 23,309 |
Organization and Description of
Organization and Description of Business | 12 Months Ended |
Dec. 31, 2019 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Organization and Description of Business | Note 1. Eidos Therapeutics, Inc., or the Company, was incorporated as an S corporation in the state of Delaware on August 6, 2013. The Company was converted into a C corporation on April 4, 2016 in conjunction with its Series Seed redeemable convertible preferred stock financing. The Company is advancing a drug candidate, AG10 to treat multiple forms of transthyretin, or TTR, amyloidosis, or ATTR which leads to organ damage, loss of organ function and eventual death from abnormal buildup of protein deposits predominantly in the heart and peripheral nervous system. AG10 is an orally-administered small molecule designed to potently stabilize tetrameric TTR, thereby halting at its outset the series of molecular events that give rise to ATTR. The Company has been primarily engaged in business planning, research and development, recruiting personnel, and raising capital. The Company is headquartered in San Francisco, California and it operates as one operating segment. Initial Public Offering 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. 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. Liquidity The Company has incurred net losses from operations since inception and has an accumulated deficit of $103.1 million as of December 31, 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 December 31, 2019, the Company has financed its operations through private placements of redeemable convertible preferred stock, debt financings, an initial public offering (IPO) of common stock, through “at-the-market” offerings, and a licensing agreement with a third party. On August 2, 2019, the Company filed a Registration Statement on Form S-3, as amended (the “2019 Shelf”) with the SEC in relation to the registration of common stock, preferred stock, warrants and units of any combination thereof. The Company also simultaneously entered into an Open Market Sale Agreement with Jefferies and SVB Leerink LLC (“Sales Agent”), to provide for the offering, issuance and sale by the Company of up to an aggregate offering price of $100.0 million of its common stock from time to time in “at-the-market” offerings under the 2019 Shelf and subject to the limitations thereof. The Company will pay to the Sales Agent cash commissions of up to 3.0 percent of the gross proceeds of sales of common stock under the 2019 Sales Agreement. The Company issued 385,613 shares and received $23.9 million net proceeds under this offering as of December 31, 2019. Based on current business plans and assuming no additional financing, the Company believes that its existing cash and cash equivalents will be sufficient to fund its cash requirements through at least the next twelve months from the date of these financial statements. The Company will need to obtain additional financing in the future and may seek financing through the issuance of its 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 | 12 Months Ended |
Dec. 31, 2019 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | Note 2. Basis of preparation These financial statements have been prepared in accordance with United States generally accepted accounting principles, or GAAP. These financial statements include transactions with BridgeBio Pharma LLC and its affiliates (“BBP LLC”), a controlling stockholder in the Company. Upon the closing of the BBP LLC IPO on July 1, 2019, all unitholders of BridgeBio Pharma LLC exchanged their units for shares of common stock of BridgeBio Pharma, Inc.(“BridgeBio” or “BBP, Inc.”), and BridgeBio Pharma LLC became a wholly-owned subsidiary of BBP, Inc. (the “Reorganization”). As the sole managing member, BBP, Inc. operates and controls all of BridgeBio Pharma LLC’s businesses and affairs after the Reorganization. For the periods presented, BBP, Inc. 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. 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 revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including, but not limited to, those related to revenue recognition, the period of performance, identification of deliverables and evaluation of regulatory and royalty milestones with respect to our license agreement, 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. 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. The Company’s cash equivalents are invested in highly-rated money market funds. 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 Property and equipment, net Property and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, ranging from three to five years. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful lives of the assets. Maintenance and repairs are charged to expense as incurred. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the balance sheet and any resulting gain or loss is reflected in operations in the period realized. 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 fair value of the assets or asset groups. There have been no such impairments of long-lived assets for any of the periods presented. Research and development costs and accrued research and development Research and development costs are expensed as incurred and consist of salaries and benefits, stock-based compensation expense, lab supplies and facility costs, as well as fees paid to others that conduct certain research and development activities on the Company’s behalf. The Company accrues for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical studies and clinical trials, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued expenses and other payables in the balance sheets and within research and development expense in the statements of operations. These costs are a significant component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers. The Company makes significant judgments and estimates in determining the accrued liabilities balance at each reporting date. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed, number of patients enrolled, and the rate of patient enrollments may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations. 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 is reclassified to additional paid-in capital as the Company’s repurchase right lapses. Redeemable convertible preferred stock tranche liabilities 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 initially measured at fair value and are subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. There were no such liabilities outstanding at December 31, 2019 or 2018, respectively. Embedded derivative liability and deemed dividend on Convertible Promissory Notes The Company determined that the automatic conversion of the Convertible Promissory Notes payable issued in 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 redeemable convertible preferred stock (Series B Preferred Stock) in March 2018. The deemed dividend impacted loss available to common stockholders and earnings per share for the year ended December 31, 2018 . Embedded derivative liability on Loan Agreement The Company determined that the requirement in its SVB and Hercules Loan Agreement (see Note 5) to pay a fee (“Success Fee”) upon certain events is an embedded derivative liability to be measured at fair value. The Success Fee amount is $1.0 million if conditions are met prior to November 13, 2021 and $2.0 million if conditions are met after November 13, 2021. The Company also determined that certain events of default provisions resulting in the prepayment of the loan or a change in the default rate of interest should also be recorded as an embedded derivative liability but were deemed immaterial for this reporting period due to the triggers being deemed unlikely. The compound embedded derivative related to the SVB and Hercules Loan Agreement is subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. 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 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 gain on extinguishment of convertible promissory notes payable impacted loss available to common stockholders and earnings per share for the year ended December 31, 2018. Net Loss per 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, 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. Revenue recognition The Company recognizes revenue in accordance with ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”), when the customer obtains control of promised goods or services, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods or services. To determine the appropriate revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the Company satisfies its performance obligation. The Company applies the five-step model to contracts when it is probable that the Company will collect the consideration the Company is entitled to in exchange for the goods or services the Company transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and identifies, as a performance obligation, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. Contract Revenues from License Agreements In the normal course of business, the Company conducts research and development programs independently pursuant to which the Company may license certain rights of the Company’s intellectual property to third parties. The terms of these arrangements typically include payment to the Company for a combination of one or more of the following: upfront license fees; development, regulatory and commercial milestone payments; product supply services; and royalties on net sales of licensed products. Upfront license fees: If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company will recognize revenue from upfront license fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company determines whether the combined performance obligation is satisfied over time or at a point in time. Development, regulatory or commercial milestone payments: At the inception of each arrangement that includes payments based on the achievement of certain development, regulatory and commercial or launch events, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company’s or the licensee’s control, such as regulatory approvals, are not considered probable of being achieved until uncertainty associated with the approvals has been resolved. At the end of each subsequent reporting period, the Company will re-evaluate the probability of achieving such development and regulatory milestones and any related constraint, and if necessary, adjust the Company’s estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis and recorded as part of contract revenues from collaborations during the period of adjustment. Product supply services: Arrangements that include a promise for the future supply of drug product for either clinical development or commercial supply at the licensee’s discretion are generally considered as options. The Company assesses if these options provide a material right to the licensee and if so, they would be accounted for as separate performance obligations. Sales-based milestone payments and royalties: For arrangements that include sales-based royalties, including milestone payments based on the volume of sales, the Company will determine whether the license is deemed to be the predominant item to which the royalties or sales-based milestones relate and if such is the case, the Company will recognize revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). Upfront payments and fees are recorded as deferred revenue when due and payable, and may require deferral of revenue recognition to a future period until the Company performs its obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the customer and the transfer of the promised goods or services to the customer will be one year or less. Cost of license revenue Cost of license revenue includes sublicensing fees payable to Stanford in the period incurred under the terms of the Stanford Agreement (see Note 12) corresponding to the recognition of license revenue from Alexion. Cost of license revenue does not include any allocated overhead costs. Stock-based compensation The Company periodically grants stock options and awards to employees and non-employees in non-capital raising transactions as compensation for services rendered. The Company accounts for stock option grants to employees, whereby the fair value of the award is measured on the date of grant and recognized over the vesting period. The Company accounts for stock option grants to non-employees whereby the amount of stock compensation expense recognized is determined based upon the measurement date at either a) the date at which a performance commitment is reached, or b) at the date at which the necessary performance to earn the equity instruments is complete. The Company believes that the estimated fair value of stock options is more readily measurable than the fair value of the services rendered. The fair value of the Company's common stock option grants is estimated using a Black-Scholes option pricing model, which uses certain assumptions related to risk-free interest rates, expected volatility, expected life of the common stock options, and future dividends. Compensation expense is recognized based upon the value derived from the Black-Scholes option pricing model and based on actual experience. The Company has elected to recognize the actual forfeitures by reducing the employee stock-based compensation expense in the same period as the forfeitures occur. The Company has in the past issued restricted shares of its common stock for share-based compensation programs. The Company measures compensation cost with respect to restricted shares issued to employees based upon the estimated fair value of the equity instruments at the date of the grant, with expenses recognized over the period which an employee is required to provide services in exchange for the award. Income taxes The Company uses the asset and liability method to account for income taxes. Under this method, deferred tax assets and liabilities are determined based on future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, and tax loss and credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment date. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that has a greater than 50% likelihood of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company records interest and penalties related to unrecognized tax benefits in income tax expense. To date, there have been no interest or penalties recorded for unrecognized tax benefits. Reclassifications Certain amounts within the statements of operations and comprehensive loss and statements of cash flows for the prior periods have been reclassified to conform with the current period presentation. These reclassifications had no impact on the Company's previously reported financial position for any of the periods presented . Recent accounting pronouncements Effective January 1, 2019, the Company adopted Accounting Standards Update (“ASU”) No. 2016-02, 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 or lease commencement 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 straightline basis over the lease term and is included in operating expenses on the 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 Note 13 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 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 In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 requires an entity to utilize a new impairment model that requires measurement and recognition of expected credit losses for most financial assets and certain other instruments, including but not limited to available-for-sale debt securities. Credit losses relating to available-for-sale debt securities will be recorded through an allowance for credit losses rather than as a direct write-down to the security. The standard is effective for fiscal years, and interim periods within those years, beginning after December 15, 2019. In November 2019, the FASB issued ASU No. 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815) and Leases (Topic 842): Effective Dates, which defers the effective date of this ASU to fiscal years beginning after December 15, 2022 for all entities except SEC reporting companies that are not smaller reporting companies. As a smaller reporting company, this ASU will now be effective for the Company beginning January 1, 2023; however, early adoption is permitted. The Company is currently evaluating the impact of adopting the updated provisions and does not anticipate that the adoption of this standard will have a material impact on its financial statements. |
Fair Value Measurements
Fair Value Measurements | 12 Months Ended |
Dec. 31, 2019 | |
Fair Value Disclosures [Abstract] | |
Fair Value Measurements | Note 3. Fair value measurements 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): December 31, 2019 Total Level 1 Level 2 Level 3 Assets: Money Market Funds $ 191,157 $ 191,157 $ — $ — Total financial assets $ 191,157 $ 191,157 $ — $ — Liabilities: Embedded Derivative $ 1,165 $ — $ — $ 1,165 Total financial liabilities $ 1,165 $ — $ — $ 1,165 There were no financial liabilities at December 31, 2018. Following is the activity related to Level 3 financial liabilities of the Company. Redeemable convertible preferred stock tranche liabilities Series seed redeemable convertible preferred stock tranche liability The fair value of the Series Seed redeemable convertible preferred stock tranche liabilities were based on significant inputs not observed in the market and thus represents a Level 3 measurement. a Black-Scholes option pricing model. 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. The following table sets forth a summary of the changes in the fair value of the Company’s Level 3 financial instrument as follows (in thousands): Year Ended December 31, 2018 2017 Redeemable convertible preferred stock tranche liability: Beginning balance $ — $ 315 Issuance of Series B redeemable convertible preferred stock tranche liability 64 — Change in fair value upon revaluation recognized in other income (expense), net 630 (75 ) Settlement of redeemable convertible preferred stock tranche liability due to the issuance of redeemable convertible preferred stock (694 ) (240 ) 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). There was no activity for the year ended December 31, 2019. The following table sets forth a summary of the changes in the fair value of the Company’s redeemable convertible preferred stock warrant liability for the year ended December 31, 2018 (in thousands): Year Ended December 31, 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 $ — 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 Year Ended December 31, 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 $ — Embedded derivative liability in the loan payable For the SVB and Hercules Loan entered in November 2019 (see Note 5) the Company determined that the requirement to pay a fee (“Success Fee”) upon certain events is an embedded derivative liability to be measured at fair value. 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 loan payable (in thousands): Year Ended December 31, 2019 Derivative instrument: Beginning balance $ — Initial fair value of the embedded derivative liability issued with the Loan payable 1,148 Change in fair value upon revaluation recognized in other income (expense), net 17 Ending balance $ 1,165 |
Balance Sheet Components
Balance Sheet Components | 12 Months Ended |
Dec. 31, 2019 | |
Balance Sheet Related Disclosures [Abstract] | |
Balance Sheet Components | Note 4. Balance sheet components Property and equipment, net Property and equipment, net consisted of the following (in thousands): December 31, 2019 2018 Leasehold improvements $ 1,112 $ 86 Computer equipment 139 87 Office furniture and equipment 109 96 Total property and equipment, cost 1,360 269 Less: accumulated depreciation and amortization (101 ) (60 ) Total property and equipment, net $ 1,259 $ 209 All the Company’s property and equipment is located in the United States. Depreciation and amortization expense for the years ended December 31, 2019, 2018 and 2017 was $77,000, $56,000 and $4,000, respectively. Accrued expenses and other current liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, 2019 2018 Accrued research and development costs $ 3,968 $ 2,055 Accrued employee related expenses 1,865 78 Liability for unvested stock, short-term 143 142 Accrued other current liabilities 433 302 Total accrued expenses and other current liabilities $ 6,409 $ 2,577 As of December 31, 2019, and 2018, balances of $95,000 and $244,000, respectively, in other liabilities related to the long-term liability for unvested stock. Lease liabilities Lease liabilities consist of the following (in thousands): December 31, 2019 Lease liabilities, current $ 554 Lease liabilities, non-current 4,591 Total lease liabilities $ 5,145 |
Debt Obligations
Debt Obligations | 12 Months Ended |
Dec. 31, 2019 | |
Debt Disclosure [Abstract] | |
Debt Obligations | Note 5. Debt obligations February 2018 Promissory Notes In February 2018, the Company entered into a Note and Warrant Purchase Agreement with BBP LLC and Stanford University (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 year ended December 31, 2018, the Company recognized interest expense of $1.0 million. 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) offering 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 Company’s Series B redeemable convertible 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. Silicon Valley Bank and Hercules loan agreement On November 13, 2019, the Company entered into the SVB and Hercules Loan Agreement. The SVB and Hercules Loan Agreement provides for up to $55.0 million in term loans to be drawn in three tranches as follows: (i) Tranche A loan of $17.5 million, (ii) Tranche B loan of up to $22.5 million which is available to be drawn until October 31, 2020, and (iii) Tranche C loan of up to $15.0 million available to be drawn upon a clinical trial milestone. The Tranche C loan is available to be drawn until September 30, 2021. The Tranche A loan of $17.5 million was drawn on November 13, 2019. There have not been any additional draws on the other tranches as of December 31, 2019. The Tranche A loan bears interest at a fixed rate equal to the greater of either (i) 8.50% or (ii) 3.25% plus the prime rate as reported in The Wall Street Journal (8.50% as of December 31, 2019). The Tranche A loan also provides for a $0.3 million commitment fee that was paid at closing and a final payment charge equal to 5.95% multiplied by the amount funded to be paid when the loan becomes due or upon prepayment of the facility. If the Company elects to prepay the Tranche A loan, there is also a prepayment fee of between 0.75% and 2.50% of the principal amount being prepaid depending on the timing and circumstances of prepayment. The Tranche A loan is secured by substantially all of the Company’s assets, except the Company’s intellectual property, which is the subject of a negative pledge. Embedded derivatives and debt discounts On issuance, the net carrying value of the Tranche A loan was $16.1 million after deducting for various discounts on issuance of $2.5 million. The discounts relate to the recognition of a bifurcated compound embedded derivative liability of $1.1 million, the final payment charge of $1.0 million due on maturity, the $0.3 million commitment fee paid at closing and $0.1 million in other debt issuance costs. The debt discounts are being amortized to interest expense over the life of the Tranche A loan using the effective interest rate method. The Company determined that the requirement in its SVB and Hercules Loan Agreement to pay a Success Fee in certain events is an embedded derivative liability requiring bifurcation from the Tranche A loan proceeds and separate accounting. The Success Fee amount is $1.0 million if conditions are met prior to November 13, 2021 and $2.0 million if conditions are met after November 13, 2021. The Company also determined that certain events of default provisions resulting in the prepayment of the loan or a change in the default rate of interest should also be recorded as an embedded derivative liability but were deemed immaterial for this reporting period due to the triggers being deemed unlikely. The Company recorded a compound embedded derivative liability of $1.1 million on issuance, which was recorded as a derivative liability in other long-term liabilities on the balance sheet and as a corresponding debt discount. The Company calculated the fair values of the derivative liability on issuance and as of December 31, 2019 based on a probability weighted valuation of certain event outcomes and discounted to the present value. The key valuation assumptions used consist of the discount rate of 11.6% and the probability of an underlying event triggering the Success Fee payment and the timing of such events. The derivative liability is being remeasured at each financial reporting period with any changes in fair value being recognized as a component of other income (expense), net. The fair value of the derivative liability was approximately $1.2 million as of December 31, 2019 and was classified as other long-term liabilities on the balance sheet and there was a $17,000 change in the fair value of the derivative liability for the year ended December 31, 2019. The facility fee, fair value of the bifurcated embedded derivative liability on issuance, and other debt issuance costs have been treated as debt discounts on the Company’s balance sheet and together with the final payment charge are being amortized to interest expense throughout the life of the Tranche A loan using the effective interest rate method. As of December 31, 2019, the net carrying value of the Tranche A loan is $16.1 million. As of December 31, 2019, there are unamortized debt discounts of $2.4 million. The Company recorded interest expense and amortization of the debt discount in the amount of $0.3 million on the Tranche A loan for the year ended December 31, 2019. Future minimum payments The following table presents future payments of principal, interest and final payment charge on the Tranche A loan as of December 31, 2019: Year Ending December 31: 2020 $ 1,512 2021 2,961 2022 9,787 2023 8,622 Total 22,882 Less: amount representing interest (4,340 ) Less: unamortized debt discount associated with the issuance of a compound embedded derivative liability, final payment charge and other debt issuance costs (2,430 ) Total carrying value $ 16,112 |
Related Party Transactions
Related Party Transactions | 12 Months Ended |
Dec. 31, 2019 | |
Related Party Transactions [Abstract] | |
Related Party Transactions | Note 6. Related party transactions BridgeBio Pharma, Inc. BBP, Inc. through its ownership of BBP LLC, is a controlling stockholder in the Company, as it owned 64.6% and 61% of the Company’s total outstanding shares as of December 31, 2019 and 2018, respectively. In April 2016, the Company began receiving consulting, management, facility and infrastructure services pursuant to a services agreement with a subsidiary of BBP, Inc. The initial agreement was entered into on March 1, 2016 and was superseded by the subsequent agreement effective as of May 1, 2017. The Company incurred the following expenses under the applicable services agreement with BBP LLC (in thousands): Year Ended December 31, 2019 2018 2017 Rent $ (54 ) $ 39 $ 76 Facility — 121 65 Consulting 573 999 656 $ 519 $ 1,159 $ 797 As of December 31, 2019, and 2018, the Company had outstanding receivables from BBP, Inc. of $85,000 and $34,000, respectively, related to providing services to other related companies of BBP, Inc. As of December 31, 2019, and 2018, the Company had outstanding liabilities due to BBP, Inc. of $0.3 million and $0.2 million, respectively. Founders 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 stablizers. 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. In September 2017, the Company issued to Dr. Graef 195,273 shares of common stock in order to offset dilution to her ownership in connection with the Company’s issuance of additional shares of Series Seed Preferred Stock in financing transactions. The Company recognized the entire expense for these awards upon the closing of the fourth tranche of the Series Seed Preferred Stock financing due to the awards being associated with the anti-dilution rights related to the Series Seed Preferred Stock financings, and determined the vesting related to these awards to be non substantive. In addition, the Company agreed to make a “gross-up” payment of $83,073 to Dr. Graef for the taxes owed by Dr. Graef as a result of such issuance of common stock, which payment was made in January 2018. 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 stablizers. 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. In September 2017, the Company issued to Dr. Alhamadsheh 195,273 shares of common stock in order to offset dilution to his ownership in connection with the Company’s issuance of additional shares of Series Seed Preferred Stock in financing transactions. The Company recognized the entire expense for these awards upon the closing of the fourth tranche of the Series Seed Preferred Stock financing due to the awards being associated with the anti-dilution rights related to the Series Seed Preferred Stock financings, and determined the vesting related to these awards to be non substantive. In addition, the Company agreed to make a “gross-up” payment of $83,073 to Dr. Alhamadsheh for the taxes owed by Dr. Alhamadsheh as a result of such issuance of common stock, which payment was made in January 2018. 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 research and development expenses for services under these consulting agreements and stock-based compensation (in thousands): Year Ended December 31, 2019 2018 2017 Dr. Graef $ 150 $ 150 $ 279 Dr. Alhamadsheh 115 115 244 $ 265 $ 265 $ 523 Option award to Dr. Huh In May 2018, the Company’s board of directors approved a grant to Dr. Huh (a member of the board of directors) of an option to purchase 83,720 shares of common stock pursuant to the Company’s Amended and Restated 2018 Stock Option and Incentive Plan (the “2018 Plan”). For the total 83,720 shares granted, 43,056 options were granted for director services. The remaining 40,664 options were granted for consulting services provided to the Company. The option was subject to vesting 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. Dr. Huh resigned from the Company’s board of directors in December 2018, at which time all options were cancelled. |
Redeemable Convertible Preferre
Redeemable Convertible Preferred Stock | 12 Months Ended |
Dec. 31, 2019 | |
Temporary Equity Disclosure [Abstract] | |
Redeemable Convertible Preferred Stock | Note 7. Redeemable convertible preferred stock Series Seed Preferred Stock Financing In April 2016, the Company completed a Series Seed redeemable convertible preferred stock (Series Seed Preferred Stock) financing. The initial total committed amount was $8.0 million to be received in three tranches. The first tranche of $1.0 million was received and 754,831 shares were issued in April 2016 and the second tranche of $3.0 million was received and 2,264,492 shares were issued in September 2016. The third tranche of $4.0 million was received and 3,019,323 shares were issued in March 2017. In September 2017, the Company completed an extension of its Series Seed Preferred Stock financing for a total of $9.0 million and 6,793,477 shares of Series Seed Preferred Stock were issued. The Company also converted its related party note payable, tranche liability and accrued interest of $32,000 into 24,202 shares of Series Seed Preferred Stock concurrently with the closing of the first tranche of this financing in April 2016 (see Note 8). Series B Preferred Stock Financing 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 thus the tranche liability of $0.7 million 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. The table below provides information on the Company’s redeemable convertible preferred stock as of December 31, 2017 (in thousands, except shares and original issue price ): Proceeds, net of Liquidation Shares Shares Price issuance cost amount Series authorized outstanding per share (in thousands) (in thousands) Seed 14,000,000 12,856,325 $ 1.3248 $ 16,920 $ 17,032 |
Redeemable Convertible Prefer_2
Redeemable Convertible Preferred Stock Tranche Liabilities | 12 Months Ended |
Dec. 31, 2019 | |
Temporary Equity Disclosure [Abstract] | |
Redeemable Convertible Preferred Stock Tranche Liabilities | Note 8. Redeemable convertible preferred stock tranche liabilities Series Seed Preferred Stock In April 2016, the Company entered into a Series Seed Preferred Stock Purchase Agreement, or the Series Seed Agreement, for the issuance of up to 6,062,848 shares of Series Seed Preferred Stock at a price of $1.3248 per share in three closings. Upon the initial closing on April 4, 2016, 754,831 shares of Series Seed Preferred Stock Series Seed The Company has determined that the Company’s obligation to issue additional shares of its redeemable convertible preferred stock represents a freestanding financial instrument. The freestanding redeemable convertible preferred stock tranche liability (Series Seed Tranche Liability) was initially recorded at fair value, with fair value changes recognized as increases or reductions in other income (expense), net in the statements of operations. The Company continued to adjust the liability for changes in the estimated fair value until the settlement of the Series Seed Tranche Liability. The Company recorded a Series Seed Tranche Liability in April 2016 of $0.3 million related to the Series Seed Preferred Stock financing. The Company estimated the fair value of the Series Seed Tranche Liability using a Black-Scholes option pricing model and the following assumptions to determine the fair value of the redeemable convertible preferred stock tranche liability: Expected term— The expected term represents the period for which the redeemable convertible preferred stock tranche liabilities are expected to be outstanding. Expected volatility— The volatility data was estimated based on a study of publicly traded industry peer companies, as there is no trading history for the Company’s redeemable convertible preferred stock. For purposes of identifying these comparable peer companies, the Company considered the industry, stage of development, size and financial leverage. The Company has measured historical volatility over a period equivalent to the expected term and believes that historical volatility provides a reasonable estimate of future expected volatility. Expected dividends —The Black-Scholes valuation model calls for a single expected dividend yield as an input. The Company currently has no history or expectation of paying cash dividends on its preferred stock. Risk-free interest rate— The risk-free interest rate is based on the yield available on U.S. Treasury zero-coupon issues similar in duration to the expected term of the redeemable convertible preferred stock tranche liability. The Black-Scholes option pricing model resulted in a tranche liability of $0.1 million for the second milestone closing and $0.2 million for the third milestone closing using the following assumptions: estimated equity value of $2.1 million, a term of three years, a risk-free rate of 0.92%, a volatility of 75%, and a dividend yield of 0.0%. The second milestone closing of the Series Seed Tranche Liability The Series Seed Tranche Liability for the third milestone was settled in March 2017 at the time of the final tranche closing of the Series Seed Preferred Stock and the remeasured liability balance of $0.2 million was reclassified to redeemable convertible preferred stock. The final closing fair value was remeasured with the following assumptions: estimated equity value was $4.0 million, a term of 2.3 years, a risk-free rate of 1.40%, a volatility of 70% and a dividend yield of 0.0%. Series B Redeemable Convertible Preferred Stock 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 the Series B Tranche Liability in March 2018 of $0.1 million related to the Series B Preferred Stock. The Company estimated the fair value of the Series B Tranche Liability using a Black-Scholes option pricing model using the following assumptions: Expected term —The expected term represents the period for which the redeemable convertible preferred stock tranche liability is expected to be outstanding, which is estimated to be the remaining contractual term. Expected volatility —The volatility data was estimated based on a study of publicly traded industry peer companies, as there is no trading history for the Company’s redeemable convertible preferred stock. For purposes of identifying these comparable peer companies, the Company considered the industry, stage of development, size and financial leverage. The Company has measured historical volatility over a period equivalent to the expected term and believes that historical volatility provides a reasonable estimate of future expected volatility. Expected dividends —The Black-Scholes valuation model calls for a single expected dividend yield as an input. The Company currently has no history or expectation of paying cash dividends on its redeemable convertible preferred stock. Risk-free interest rate —The risk-free interest rate is based on the yield available on U.S. Treasury zero-coupon issues similar in duration to the expected term of the redeemable convertible preferred stock tranche liability and put option asset. The Company used the following assumptions: a term of 0.08 years, a risk-free rate of 1.63%, a volatility of 36.4%, and a dividend yield of 0.0%. In May 2018, the Company completed the closing of the Series B Preferred Stock second tranche and issued 4,430,162 shares of Series B Preferred Stock for net cash proceeds of $48.0 million. At this time the Series B Tranche Liability was remeasured at $0.7 million, determined using a probability-weighted expected return method (PWERM). The PWERM included probabilities of three scenarios including an IPO occurring in June 2018, staying private, and bankruptcy. The scenarios were weighted based on the Company’s estimate of each event occurring in deriving the estimated fair value. Upon the closing of the Series B Preferred Stock second tranche, the Series B Tranche Liability of $0.7 million was reclassified to Series B Preferred Stock . |
Stockholders' Equity and Stock-
Stockholders' Equity and Stock-Based Compensation | 12 Months Ended |
Dec. 31, 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: December 31, 2019 2018 2017 Redeemable convertible preferred stock outstanding, as converted — — 15,376,164 Options issued and outstanding 1,335,755 1,329,762 846,166 Options available for future grants 1,935,054 747,057 670,994 ESPP shares available for future grants 97,805 130,166 — 3,368,614 2,206,985 16,893,324 On August 2, 2019, the Company filed a 2019 Shelf with the SEC in relation to the registration of common stock, preferred stock, warrants and units of any combination thereof. The Company also simultaneously entered into an Open Market Sale Agreement with the Sales Agent, to provide for the offering, issuance and sale by the Company of up to an aggregate offering price of $100.0 million of its common stock from time to time in “at-the-market” offerings under the 2019 Shelf and subject to the limitations thereof. The Company will pay to the Sales Agent cash commissions of up to 3.0 percent of the gross proceeds of sales of common stock under the 2019 Sales Agreement. The Company has issued 385,613 shares under this offering and received $23.9 million of net proceeds as of December 31, 2019. Stock plans Equity Incentive Plan 2016 Equity Incentive Plan In April 2016, the Company established its 2016 Equity Incentive Plan, or the 2016 Plan, which provides for the granting of equity awards to employees and consultants of the Company. Awards granted under the 2016 Plan may be either incentive stock options, or ISOs, nonqualified stock options, or NSOs or restricted stock awards. ISOs may be granted only to Company employees (including officers and directors who are also employees). NSOs may be granted to Company employees and consultants. The exercise price of an ISO and NSO shall not be less than 100% of the estimated fair value of the shares on the date of grant, as determined by the board of directors. The exercise price of an ISO granted to an employee who at the time of grant is a 10% stockholder shall not be less than 110% of the estimated fair value of the shares on the date of grant, as determined by the board of directors. To date, ISOs and NSOs have a term of ten years and generally vest over a four-year period with annual cliff vesting and the balance monthly over 36 months. Upon completion of the Company’s IPO, the remaining shares available for issuance under the 2016 Plan were retired. Amended and Restated 2018 Stock Option and Incentive Plan In May 2018, the Company’s board of directors and stockholders approved the Amended and Restated 2018 Stock Option and Incentive Plan, or the 2018 Plan, to replace the 2016 Plan, which became effective upon the IPO. The 2018 Plan is administered by the board of directors or a committee appointed by the board of directors, which determines the types of awards to be granted, including the number of shares subject to the awards, the exercise price and the vesting schedule. Under the 2018 Plan, 598,000 shares of the Company’s common stock have been initially reserved for the issuance of stock options, restricted stock units and other awards to employees, directors and consultants. Options granted under the 2018 Plan expire no later than 10 years from the date of grant. The exercise price of each option may not be less than 100% of the fair market value of the common stock at the date of grant. Options may be granted to stockholders possessing more than 10% of the total combined voting power of all classes of stocks of the Company at an exercise price at least 110% of the fair value of the common stock at the date of grant and the options are not exercisable after the expiration of 10 years from the date of grant. Employee stock options generally vest 25% upon one year of continued service to the Company, with the remainder in monthly increments over three additional years. Upon adoption of the 2018 Plan, no additional stock awards will be issued under the 2016 Plan. Options granted under the 2016 Plan that were outstanding on the date the 2018 plan became effective remain subject to the terms of the 2016 Plan. In December 2018, the Company’s board of directors approved an increase in the number of shares reserved under the 2018 Plan by 700,000 shares, and this increase was approved by the Company’s stockholders in June 2019. In December 2019, the Company’s board of directors approved an additional increase in the number of shares reserved under the 2018 Plan by 1,500,000 shares. As of December 31, 2019, the Company has reserved 2,798,000 shares of common stock for issuance under the 2018 Plan, of which the 1,500,000 shares subject to the December 2019 increase remain subject to stockholder approval. Employee Stock Purchase Plan In May 2018, the Company’s board of directors and stockholders approved the 2018 Employee Stock Purchase Plan, or the 2018 ESPP, which became effective upon the IPO. The 2018 ESPP is intended to qualify as an employee stock purchase plan under Section 423 of the Internal Revenue Code of 1986, as amended, and is administered by the Company’s board of directors and the Compensation Committee of the board of directors. Under the 2018 ESPP, 143,520 shares of the Company’s common stock have been initially reserved for employee purchases of the Company’s common stock. The 2018 ESPP allows eligible employees to purchase shares of the Company’s common stock at a discount through payroll deductions of up to 20% of their eligible compensation. At the end of each offering period, employees are able to purchase shares at 85% of the lower of the fair market value of the Company’s common stock at the beginning of the offering period or at the end of each applicable purchase period. The first purchase period commenced upon the completion of the Company’s IPO and ended on November 30, 2018. The fair value of the rights granted under the 2018 ESPP was calculated using the Black-Scholes option-pricing model with the following assumptions: Year Ended December 31, Year Ended December 31, 2019 2018 Expected term in years 0.50 0.48 Expected volatility 63.06 % 70.40 % Risk-free interest rate 2.32 % 1.50 % Dividend yield 0 % 0 % Stock options Activity under the Company’s equity incentive plans is set forth below: 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 Additional authorized 1,500,000 — $ - Options granted (365,573 ) 365,573 $ 34.51 Options exercised — (306,010 ) $ 3.30 Options cancelled 53,570 (53,570 ) $ 7.24 Outstanding—December 31, 2019 1,935,054 1,335,755 $ 16.91 8.77 $ 54,071 Options exercisable – December 31, 2019 241,289 $ 11.16 8.50 $ 11,155 Options vested and expected to vest – December 31, 2019 1,335,755 $ 16.91 8.77 $ 54,071 Aggregate intrinsic value represents the difference between the Company’s estimated fair value of its common stock and the exercise price of outstanding in–the–money options. The total intrinsic value of options exercised was $12.3 million and $0.9 million for the years ended December 31, 2019 and 2018, respectively. The total fair value of shares vested during the years ended December 31, 2019 and 2018 was $5.2 million and $2.5 million, respectively. Stock options valuation Prior to the completion of the Company’s IPO, the fair value of the Company’s shares of common stock underlying its stock options had historically been determined by the Company’s board of directors. Because there had been no public market for the Company’s common stock prior to June 2018, the Company’s board of directors had determined fair value of the common stock at the time of grant of the option by considering a number of objective and subjective factors including important developments in the Company’s operations, valuations performed by an independent third party, sales of redeemable convertible preferred stock, actual operating results and financial performance, the conditions in the biotechnology industry and the economy in general, the stock price performance and volatility of comparable public companies, and the lack of liquidity of the Company’s common stock, among other factors. For stock options granted after the completion of the IPO, the Company determines the fair value of each share of underlying common stock based on the closing price of the Company’s common stock as reported on the date of grant. The determination of the fair value of stock-based payment awards on the date of grant is affected by the stock price, as well as assumptions regarding a number of complex and subjective variables. These variables include expected stock price volatility over the term of the awards, actual and projected employee/consultant stock option exercise behaviors, risk-free interest rates, and expected dividends. Estimating the fair value of equity-settled awards as of the grant date using valuation models, such as the Black-Scholes option pricing model, is affected by assumptions regarding a number of complex variables. These inputs include: Expected term — The expected term represents the period that the stock-based awards are expected to be outstanding. Since the Company does not have a long trading history for its common stock, the expected term is estimated based on the average expected term for comparable publicly traded biopharmaceutical companies. The comparable companies were chosen based on their similar size, stage in the life cycle or area of specialty. For non-employees, the term is the remaining contractual term of the option. Expected volatility —Since the Company does not have a long trading history for its common stock, the expected volatility is estimated based on the average volatility for comparable publicly traded biopharmaceutical companies over a period equal to the expected term of the stock option grants. The comparable companies were chosen based on their similar size, stage in the life cycle or area of specialty. Risk-free interest rate —The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of option. Expected dividend —The Company has never paid dividends on its common stock and has no plans to pay dividends on its common stock. Therefore, the Company used an expected dividend yield of zero. 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: Year Ended December 31, 2019 2018 2017 Expected term in years 6.07 6.08 5.83 Expected volatility 72.39 % 71.99 % 68.40 % Risk-free interest rate 1.95 % 2.87 % 2.27 % Dividend yield 0 % 0 % 0 % Weighted average fair value of share-based awards granted $ 22.86 $ 8.46 $ 4.79 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 non-employee stock options is estimated using the Black-Scholes valuation model with assumptions generally consistent with those used for employee stock options, with the exception of the expected term, which is the remaining contractual life at each measurement date. Year Ended December 31, 2019 2018 2017 Expected term in years 6.09 9.20 9.66 Expected volatility 73.67 % 73.87 % 80.08 % Risk-free interest rate 2.49 % 2.66 % 2.41 % Dividend yield 0 % 0 % 0 % During the years ended December 31, 2019, 2018 and 2017, the Company granted 20,361, 35,880, and 569,252 shares, respectively, to non-employee consultants. The Company recognized stock-based compensation expense for non-employee awards during the years ended December 31, 2019, 2018 and 2017 of $0.1 million, $1.7 million and $ 0.7 million, respectively. Accrued repurchase liability for common stock early exercises Stock awards granted pursuant to 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 December 31, 2019, and 2018, 524,513 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 $238,000 and $386,000, respectively. Restricted stock In December 2017, the Company issued 390,546 shares of common stock for no consideration to the founders pursuant to the Series Seed Preferred Stock Purchase Agreement and Stanford License Agreement in connection with certain anti-dilution rights held by these parties. If the shares issued under the Stanford License Agreement represent less than 1% of the shares issued and outstanding common stock on an as-converted basis, the Company will issue additional common stock to the founders and Stanford University. The Company has the right to repurchase the common stock issued to the founders for these purposes at the fair value per share on the date of repurchase; this repurchase right lapses as the shares vest. The shares cliff vest 25% after one year and vest monthly thereafter over 36 months. As of December 31, 2019, and 2018, 170,866 and 268,504 shares remained subject to repurchase, respectively. The Company recognizes stock-based compensation expense upon the approval of these awards by the board of directors in September 2017 as vesting provisions are not considered substantive due to the fair value repurchase right. Stock-based compensation expense related to the restricted stock is recognized based on the fair value of the stock on the approval date using the Black-Scholes pricing model. During the years ended December 31, 2019, 2018 and 2017, the Company recognized expense related to these awards of zero, zero, and $0.2 million, respectively. Stock-based compensation expense Total stock-based compensation expense related to all the Company’s stock-based awards was recorded on the statements of operations as follows (in thousands): Year Ended December 31, 2019 2018 2017 Research and development $ 2,313 $ 1,325 $ 519 General and administrative $ 3,060 1,201 629 Total stock-based compensation expense $ 5,373 $ 2,526 $ 1,148 Year Ended December 31, 2019 2018 2017 Stock option expense $ 5,198 $ 2,404 $ 1,148 Employee Stock Plan 175 122 — Total stock-based compensation expense $ 5,373 $ 2,526 $ 1,148 As of December 31, 2019, there was $13.5 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 2.9 years. |
Income taxes
Income taxes | 12 Months Ended |
Dec. 31, 2019 | |
Income Tax Disclosure [Abstract] | |
Income taxes | 10. Income taxes No provision for income taxes was recorded for the years ended December 31, 2019, 2018 and 2017. The Company has incurred net operating losses since its inception. The Company has not reflected any benefit of such net operating loss carryforwards in the financial statements. The Company has established a full valuation allowance against its deferred tax assets due to the uncertainty surrounding the realization of such assets. The effective tax rate differs from the federal statutory rate as follows: Year Ended December 31, 2019 2018 2017 Federal statutory income tax rate 21.0 % 21.0 % 34.0 % State income taxes 0.0 % 0.0 % 0.0 % Federal rate change impact due to Tax Act 0.0 % 0.0 % -13.4 % Research and development credits 15.5 % 3.2 % 1.5 % Stock-based compensation 2.5 % -1.5 % -1.5 % Change in fair value of convertible note 0.0 % -1.6 % 0.2 % Other 2.6 % -1.3 % -0.7 % Change in valuation allowance -41.6 % -19.8 % -20.1 % 0.00 % 0.00 % 0.00 % Year Ended December 31, 2019 2018 Deferred tax assets: Net operating loss carryforward $ 20,925 $ 13,046 Research and development credits 9,415 1,680 Stock-based compensation 328 — Lease liability 1,080 — Other 23 37 Deferred tax assets before valuation allowance 31,771 14,763 Less: valuation allowance (30,727 ) (14,566 ) Net deferred income tax assets 1,044 197 Deferred tax liabilities: Stock-based compensation — (197 ) Right of use assets (842 ) — Fixed assets (202 ) — Net deferred tax assets (liabilities) $ — $ — As of December 31, 2019, the Company has net operating loss carryforwards of approximately $84.4 million and $45.8 million, respectively, available to reduce future taxable income, if any, for federal and California state income tax purposes. The net operating losses will begin to expire in 2037. As of December 31, 2019, the Company has federal research and development credit carryforwards of $1.5 million, which will expire beginning in 2037 if not utilized. As of December 31, 2018, the Company has California research and development credit carryforwards of $1.0 million. The California research and development credits have no expiration date. As of December 31, 2019, the Company had federal orphan drug credits of $8.9 million available to offset future taxable income. The Company has established a full valuation allowance against its deferred tax assets due to the uncertainty surrounding realization of such assets. The net increase in the valuation allowance for the years ended December 31, 2019 and 2018 was $16.2 million and $10.4 million, respectively. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred income tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred income tax liabilities, and projected future taxable income in making this assessment. Based on these factors, management has provided a full valuation allowance for its deferred tax assets. Federal and state laws impose substantial restrictions on the utilization of net operating loss and tax credit carryforwards in the event of an ownership change for tax purchases, as defined in Section 382 of the Internal Revenue Code. As a result of such ownership changes, the Company’s ability to realize the potential future benefit of tax losses and tax credits that existed at the time of the ownership change may be significantly reduced. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Year Ended December 31, 2019 2018 2017 Balance at beginning of year $ 525 $ 166 $ 31 Additions based on tax positions related to current year 1,217 359 135 Balance at end of year $ 1,742 $ 525 $ 166 The Company’s unrecognized gross tax benefits would not reduce the annual effective tax rate if recognized because it has recorded a full valuation allowance on its deferred tax assets. The Company does not foresee any material changes to the gross unrecognized tax benefit within the next twelve months. The Company’s policy is to recognize interest and/or penalties related to income tax matters in income tax expense. The Company files income tax returns in the United States and California. The Company currently has no federal or state tax examinations in progress. All years are open for examination by federal and state authorities. |
Net loss per Share
Net loss per Share | 12 Months Ended |
Dec. 31, 2019 | |
Earnings Per Share [Abstract] | |
Net loss per Share | 11. 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 . December 31, 2019 2018 2017 Numerator: Net loss attributable to common stockholders $ (37,835 ) $ (39,812 ) $ (11,941 ) Denominator: Weighted average common shares outstanding 37,114,930 22,037,363 4,324,525 Weighted average unvested common shares subject to repurchase (490,238 ) (670,368 ) (727,852 ) Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted 36,624,692 21,366,995 3,596,673 Net loss per share attributable to common stockholders, basic and diluted $ (1.03 ) $ (1.86 ) $ (3.32 ) The following shares of potentially dilutive securities have been excluded from the diluted net loss per share computations for the years ended December 31, 2019, 2018 and 2017 because their inclusion would be anti-dilutive: December 31, 2019 2018 2017 Redeemable convertible preferred stock on an as-converted basis — — 15,376,164 ESPP shares 1,318 5,115 — Options to purchase common stock 1,335,755 1,329,762 846,163 Common stock subject to vesting or repurchase 353,647 627,530 828,843 1,690,720 1,962,407 17,051,170 |
License Agreements
License Agreements | 12 Months Ended |
Dec. 31, 2019 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
License Agreements | 12. License agreements Alexion License Agreement In September 2019, the Company entered into the Alexion License Agreement to develop, manufacture and commercialize the compound known as AG10 and any of its various chemical forms and any pharmaceutical products containing AG10 in Japan. Under the agreement, the Company received an upfront nonrefundable payment of $25.0 million. The Company also entered into a stock purchase agreement with Alexion, under which the Company sold to Alexion 556,173 shares of the Company’s common stock at a price per share of $44.95, for an aggregate purchase price of approximately $25.0 million. The excess of the purchase price over the value of the Company’s shares, determined based on the closing price of a share of the Company’s common stock of $41.91 as reported on The Nasdaq Global Select Market as of the date of execution, was $1.7 million and recognized in revenue as part of the upfront payment as discussed below. The discount for lack of marketability (“DLOM”) was applied in accordance with ASC 820 on the date of issuance, and as a result the Company recorded a premium of $1.7 million in license revenue. The Company is also eligible to receive $30.0 million in regulatory milestone payments subject to the achievement of regulatory milestones. The Company will also receive low double-digit royalty payments based on net sales of AG10 in Japan. The royalty rate is subject to reduction if Alexion is required to obtain intellectual property rights from third parties to develop, manufacture or commercialize AG10 in Japan, or upon the introduction of generic competition into market. The Company is also in discussions with Alexion on a supply agreement that has not yet been finalized as of the period ending December 31, 2019. The Company accounted for the Alexion License Agreement under ASC 606 and identified the exclusive license as a distinct performance obligation since Alexion can benefit from the license on its own by developing and commercializing the underlying product using its own resources. In addition, the Company will enter into clinical and commercial supply agreements for the licensed territory. The Company determined that the optional right to future products under these supply agreements is not considered to represent a material right. The Company recognized the $25.0 million upfront fee and $1.7 million premium paid for the Company’s stock for a total upfront payment of $26.7 million in license revenue upon the effective date of the Alexion License Agreement in September 2019. The Company determined that the license was a right to use the Company’s intellectual property and as of the effective date, the Company had provided all necessary information to Alexion to benefit from the license and the license term had begun. The Company considers the future potential regulatory milestones of up to approximately $30.0 million and the sales-based royalties to be variable consideration. The Company excluded the regulatory milestones from the transaction price because the Company determined such payments to be fully constrained under ASC 606 due to the inherent uncertainty in the achievement of such milestone payments and are highly susceptible to factors outside of the Company’s control. As the sales-based royalties are all related to the license of the IP, the Company will recognize revenue in the period when subsequent sales are made pursuant to the sales-based royalty exception under ASC 606-10-55-65. The Company will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. Additionally, during the year ended December 31, 2019, the Company recognized $26.7 million in revenue related to the Alexion License Agreement. Acquired license Stanford License Agreement In April 2016, the Company entered into an exclusive license agreement (the “Stanford License Agreement”) with the Board of Trustees of the Leland Stanford Junior University (“Stanford University”), 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. The Company paid an upfront license payment of $25,000 in April 2016, which was recorded as general and administrative expense and also issued 56,809 shares of common stock. In March 2017, the Company paid a 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 recorded $50,000 under the Stanford License Agreement in connection with the achievement of a development milestone. Under the Stanford License Agreement, the Company will pay Stanford a percentage of all non-royalty sublicensing consideration attributable to the sublicense of the licensed compounds. The Stanford License Agreement states that if this event occurs in the third year, 10% is payable to Stanford. During the year ended December 31, 2019, the Company recognized expense of $2.5 million incurred under the Stanford License Agreement related to the recognition of license revenue from Alexion, which was recorded as cost of license revenue. |
Commitments and Contingencies
Commitments and Contingencies | 12 Months Ended |
Dec. 31, 2019 | |
Commitments And Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | 13. 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 $0.2 million as collateral for the lease, which is included in other assets on the balance sheet at December 31, 2018. On March 27, 2019 the Company entered into an amendment to the lease dated November 14, 2017 and the new lease commenced in August 2019. In connection with the amendment the Company leases 10,552 rentable square feet. The amended lease is for 87 months and has $6.4 million of payments under this lease. 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 the Company’s prior lease. Upon the commencement of the amended lease, the Company recognized $56,000 in tenant improvements from the prior lease as expense, a gain on extinguishment of the previous lease liability of $69,000, and wrote-off the total ROU assets and lease liabilities of $1.0 million and $1.0 million, respectively. As of December 31, 2019, total ROU assets and lease liabilities per the amended lease were approximately $4.0 million and $5.1 million, respectively. All operating lease expense is recognized on a straight-line basis over the lease term. Other information related to the operating lease: Year Ended December 31, 2019 Cash payments over lease term (in thousands) $ 6,296 Weighted average remaining lease term (months) 82 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 December 31, 2019 are as follows (in thousands): Operating Year Lease Commitments 2020 $ 844 2021 869 2022 896 2023 922 2024 950 Thereafter 1,815 $ 6,296 The Company’s rent expense for the years ended December 31, 2019, 2018 and 2017 was $0.6 million, $0.4 million and $0.1 million, respectively. The amounts include amounts incurred pursuant to the service agreement with BridgeBio Services, Inc., an affiliate of BridgeBio Pharma LLC (see Note 6). Rent expense is recognized on a straight-line basis over the terms of the Company’s leases and accordingly, the Company recorded the difference between rent expense and amount paid under the leases as deferred rent liability within other liabilities in the balance sheets. Incentives granted under the Company’s facility lease, including allowances to fund leasehold improvements, are deferred and recognized as adjustments to rent expense on a straight-line basis over the term of the lease. 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. Legal proceedings From time to time, the Company may be involved in a variety of claims, lawsuits, investigations and proceedings relating to securities laws, product liability, patent infringement, contract disputes and other matters relating to various claims that arise in the normal course of business in addition to governmental and other regulatory investigations and proceedings. In addition, third parties may, from time to time, assert claims against the Company in the form of letters and other communications. Management currently believes that these ordinary course matters will not have a material adverse effect on the Company’s business; however, the results of litigation and claims are inherently unpredictable. Regardless of the outcome, litigation can have an adverse impact on the Company because of defense and settlement costs, diversion of management resources and other factors. |
Subsequent Events
Subsequent Events | 12 Months Ended |
Dec. 31, 2019 | |
Subsequent Events [Abstract] | |
Subsequent Events | 14. Subsequent Events Subsequent to the year ended December 31, 2019, the Company has issued an additional 448,755 shares of common stock in “at-the-market” offerings under the 2019 Shelf and received $23.8 million of net proceeds. |
Supplementary Financial Data (U
Supplementary Financial Data (Unaudited) | 12 Months Ended |
Dec. 31, 2019 | |
Quarterly Financial Information Disclosure [Abstract] | |
Supplementary Financial Data (Unaudited) | 15. Supplementary Financial Data (unaudited) The following table presents the selected quarterly financial data for the years ended December 31, 2019 and 2018: Statements of Operations Quarter Ended March 31 June 30 September 30 December 31 (In thousands, except per share amounts) 2019 Income (loss) from operations $ (12,584 ) $ (14,794 ) $ 6,251 $ (19,324 ) Net income (loss) attributable to common stockholders $ (11,733 ) $ (14,053 ) $ 6,931 $ (18,980 ) Net income (loss) per share of common stock attributable to common stockholders, basic $ (0.32 ) $ (0.39 ) $ 0.19 $ (0.51 ) Net income (loss) per share of common stock attributable to common stockholders, diluted $ (0.32 ) $ (0.39 ) $ 0.18 $ (0.51 ) 2018 Loss from operations $ (7,997 ) $ (8,089 ) $ (10,988 ) $ (10,705 ) Net loss attributable to common stockholders $ (7,963 ) $ (11,381 ) $ (10,614 ) $ (9,854 ) Net loss per share of common stock attributable to common stockholders, basic and diluted $ (1.81 ) $ (1.40 ) $ (0.30 ) $ (0.27 ) |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
Dec. 31, 2019 | |
Accounting Policies [Abstract] | |
Basis of Preparation | Basis of preparation These financial statements have been prepared in accordance with United States generally accepted accounting principles, or GAAP. These financial statements include transactions with BridgeBio Pharma LLC and its affiliates (“BBP LLC”), a controlling stockholder in the Company. Upon the closing of the BBP LLC IPO on July 1, 2019, all unitholders of BridgeBio Pharma LLC exchanged their units for shares of common stock of BridgeBio Pharma, Inc.(“BridgeBio” or “BBP, Inc.”), and BridgeBio Pharma LLC became a wholly-owned subsidiary of BBP, Inc. (the “Reorganization”). As the sole managing member, BBP, Inc. operates and controls all of BridgeBio Pharma LLC’s businesses and affairs after the Reorganization. For the periods presented, BBP, Inc. 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. |
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 revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including, but not limited to, those related to revenue recognition, the period of performance, identification of deliverables and evaluation of regulatory and royalty milestones with respect to our license agreement, 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. 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. The Company’s cash equivalents are invested in highly-rated money market funds. |
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 |
Property and Equipment, Net | Property and equipment, net Property and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, ranging from three to five years. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful lives of the assets. Maintenance and repairs are charged to expense as incurred. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the balance sheet and any resulting gain or loss is reflected in operations in the period realized. |
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 fair value of the assets or asset groups. There have been no such impairments of long-lived assets for any of the periods presented. |
Research and Development Costs and Accrued Research and Development | Research and development costs and accrued research and development Research and development costs are expensed as incurred and consist of salaries and benefits, stock-based compensation expense, lab supplies and facility costs, as well as fees paid to others that conduct certain research and development activities on the Company’s behalf. The Company accrues for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical studies and clinical trials, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued expenses and other payables in the balance sheets and within research and development expense in the statements of operations. These costs are a significant component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers. The Company makes significant judgments and estimates in determining the accrued liabilities balance at each reporting date. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed, number of patients enrolled, and the rate of patient enrollments may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations. |
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 is reclassified to additional paid-in capital as the Company’s repurchase right lapses. |
Redeemable Convertible Preferred Stock Tranche Liability | Redeemable convertible preferred stock tranche liabilities 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 initially measured at fair value and are subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. There were no such liabilities outstanding at December 31, 2019 or 2018, respectively. |
Embedded Derivative Liability | Embedded derivative liability and deemed dividend on Convertible Promissory Notes The Company determined that the automatic conversion of the Convertible Promissory Notes payable issued in 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 redeemable convertible preferred stock (Series B Preferred Stock) in March 2018. The deemed dividend impacted loss available to common stockholders and earnings per share for the year ended December 31, 2018 . Embedded derivative liability on Loan Agreement The Company determined that the requirement in its SVB and Hercules Loan Agreement (see Note 5) to pay a fee (“Success Fee”) upon certain events is an embedded derivative liability to be measured at fair value. The Success Fee amount is $1.0 million if conditions are met prior to November 13, 2021 and $2.0 million if conditions are met after November 13, 2021. The Company also determined that certain events of default provisions resulting in the prepayment of the loan or a change in the default rate of interest should also be recorded as an embedded derivative liability but were deemed immaterial for this reporting period due to the triggers being deemed unlikely. The compound embedded derivative related to the SVB and Hercules Loan Agreement is subject to remeasurement with changes in fair value recognized in other income (expense), net in the statements of operations. |
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 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 gain on extinguishment of convertible promissory notes payable impacted loss available to common stockholders and earnings per share for the year ended December 31, 2018. |
Net Loss per Attributable to Common Stockholders and Net Loss per Share | Net Loss per 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, 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. |
Revenue Recognition | Revenue recognition The Company recognizes revenue in accordance with ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”), when the customer obtains control of promised goods or services, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods or services. To determine the appropriate revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the Company satisfies its performance obligation. The Company applies the five-step model to contracts when it is probable that the Company will collect the consideration the Company is entitled to in exchange for the goods or services the Company transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and identifies, as a performance obligation, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. Contract Revenues from License Agreements In the normal course of business, the Company conducts research and development programs independently pursuant to which the Company may license certain rights of the Company’s intellectual property to third parties. The terms of these arrangements typically include payment to the Company for a combination of one or more of the following: upfront license fees; development, regulatory and commercial milestone payments; product supply services; and royalties on net sales of licensed products. Upfront license fees: If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company will recognize revenue from upfront license fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company determines whether the combined performance obligation is satisfied over time or at a point in time. Development, regulatory or commercial milestone payments: At the inception of each arrangement that includes payments based on the achievement of certain development, regulatory and commercial or launch events, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company’s or the licensee’s control, such as regulatory approvals, are not considered probable of being achieved until uncertainty associated with the approvals has been resolved. At the end of each subsequent reporting period, the Company will re-evaluate the probability of achieving such development and regulatory milestones and any related constraint, and if necessary, adjust the Company’s estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis and recorded as part of contract revenues from collaborations during the period of adjustment. Product supply services: Arrangements that include a promise for the future supply of drug product for either clinical development or commercial supply at the licensee’s discretion are generally considered as options. The Company assesses if these options provide a material right to the licensee and if so, they would be accounted for as separate performance obligations. Sales-based milestone payments and royalties: For arrangements that include sales-based royalties, including milestone payments based on the volume of sales, the Company will determine whether the license is deemed to be the predominant item to which the royalties or sales-based milestones relate and if such is the case, the Company will recognize revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). Upfront payments and fees are recorded as deferred revenue when due and payable, and may require deferral of revenue recognition to a future period until the Company performs its obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the customer and the transfer of the promised goods or services to the customer will be one year or less. |
Cost of License Revenue | Cost of license revenue Cost of license revenue includes sublicensing fees payable to Stanford in the period incurred under the terms of the Stanford Agreement (see Note 12) corresponding to the recognition of license revenue from Alexion. Cost of license revenue does not include any allocated overhead costs. |
Stock-Based Compensation | Stock-based compensation The Company periodically grants stock options and awards to employees and non-employees in non-capital raising transactions as compensation for services rendered. The Company accounts for stock option grants to employees, whereby the fair value of the award is measured on the date of grant and recognized over the vesting period. The Company accounts for stock option grants to non-employees whereby the amount of stock compensation expense recognized is determined based upon the measurement date at either a) the date at which a performance commitment is reached, or b) at the date at which the necessary performance to earn the equity instruments is complete. The Company believes that the estimated fair value of stock options is more readily measurable than the fair value of the services rendered. The fair value of the Company's common stock option grants is estimated using a Black-Scholes option pricing model, which uses certain assumptions related to risk-free interest rates, expected volatility, expected life of the common stock options, and future dividends. Compensation expense is recognized based upon the value derived from the Black-Scholes option pricing model and based on actual experience. The Company has elected to recognize the actual forfeitures by reducing the employee stock-based compensation expense in the same period as the forfeitures occur. The Company has in the past issued restricted shares of its common stock for share-based compensation programs. The Company measures compensation cost with respect to restricted shares issued to employees based upon the estimated fair value of the equity instruments at the date of the grant, with expenses recognized over the period which an employee is required to provide services in exchange for the award. |
Income Taxes | Income taxes The Company uses the asset and liability method to account for income taxes. Under this method, deferred tax assets and liabilities are determined based on future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, and tax loss and credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment date. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that has a greater than 50% likelihood of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company records interest and penalties related to unrecognized tax benefits in income tax expense. To date, there have been no interest or penalties recorded for unrecognized tax benefits. |
Reclassifications | Reclassifications Certain amounts within the statements of operations and comprehensive loss and statements of cash flows for the prior periods have been reclassified to conform with the current period presentation. These reclassifications had no impact on the Company's previously reported financial position for any of the periods presented . |
Recent Accounting Pronouncements | Recent accounting pronouncements Effective January 1, 2019, the Company adopted Accounting Standards Update (“ASU”) No. 2016-02, 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 or lease commencement 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 straightline basis over the lease term and is included in operating expenses on the 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 Note 13 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 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 In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 requires an entity to utilize a new impairment model that requires measurement and recognition of expected credit losses for most financial assets and certain other instruments, including but not limited to available-for-sale debt securities. Credit losses relating to available-for-sale debt securities will be recorded through an allowance for credit losses rather than as a direct write-down to the security. The standard is effective for fiscal years, and interim periods within those years, beginning after December 15, 2019. In November 2019, the FASB issued ASU No. 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815) and Leases (Topic 842): Effective Dates, which defers the effective date of this ASU to fiscal years beginning after December 15, 2022 for all entities except SEC reporting companies that are not smaller reporting companies. As a smaller reporting company, this ASU will now be effective for the Company beginning January 1, 2023; however, early adoption is permitted. The Company is currently evaluating the impact of adopting the updated provisions and does not anticipate that the adoption of this standard will have a material impact on its financial statements. |
Fair Value Measurements (Tables
Fair Value Measurements (Tables) | 12 Months Ended |
Dec. 31, 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): December 31, 2019 Total Level 1 Level 2 Level 3 Assets: Money Market Funds $ 191,157 $ 191,157 $ — $ — Total financial assets $ 191,157 $ 191,157 $ — $ — Liabilities: Embedded Derivative $ 1,165 $ — $ — $ 1,165 Total financial liabilities $ 1,165 $ — $ — $ 1,165 |
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 Level 3 financial instrument as follows (in thousands): Year Ended December 31, 2018 2017 Redeemable convertible preferred stock tranche liability: Beginning balance $ — $ 315 Issuance of Series B redeemable convertible preferred stock tranche liability 64 — Change in fair value upon revaluation recognized in other income (expense), net 630 (75 ) Settlement of redeemable convertible preferred stock tranche liability due to the issuance of redeemable convertible preferred stock (694 ) (240 ) 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 for the year ended December 31, 2018 (in thousands): Year Ended December 31, 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 $ — |
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 Convertible Promissory Notes payable (in thousands): Year Ended December 31, 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 $ — |
Schedule of Embedded Derivative in Loan Payable | The following table sets forth a summary of the changes in the fair value of the Company’s embedded derivative liability in the loan payable (in thousands): Year Ended December 31, 2019 Derivative instrument: Beginning balance $ — Initial fair value of the embedded derivative liability issued with the Loan payable 1,148 Change in fair value upon revaluation recognized in other income (expense), net 17 Ending balance $ 1,165 |
Balance Sheet Components (Table
Balance Sheet Components (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Balance Sheet Related Disclosures [Abstract] | |
Schedule of Property and Equipment, Net | Property and equipment, net consisted of the following (in thousands): December 31, 2019 2018 Leasehold improvements $ 1,112 $ 86 Computer equipment 139 87 Office furniture and equipment 109 96 Total property and equipment, cost 1,360 269 Less: accumulated depreciation and amortization (101 ) (60 ) Total property and equipment, net $ 1,259 $ 209 |
Schedule of Accrued Expenses and Other Current Liabilities | Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, 2019 2018 Accrued research and development costs $ 3,968 $ 2,055 Accrued employee related expenses 1,865 78 Liability for unvested stock, short-term 143 142 Accrued other current liabilities 433 302 Total accrued expenses and other current liabilities $ 6,409 $ 2,577 |
Schedule of Lease Liabilities | Lease liabilities consist of the following (in thousands): December 31, 2019 Lease liabilities, current $ 554 Lease liabilities, non-current 4,591 Total lease liabilities $ 5,145 |
Debt Obligations (Tables)
Debt Obligations (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Debt Disclosure [Abstract] | |
Schedule of Future Minimum Payments | The following table presents future payments of principal, interest and final payment charge on the Tranche A loan as of December 31, 2019: Year Ending December 31: 2020 $ 1,512 2021 2,961 2022 9,787 2023 8,622 Total 22,882 Less: amount representing interest (4,340 ) Less: unamortized debt discount associated with the issuance of a compound embedded derivative liability, final payment charge and other debt issuance costs (2,430 ) Total carrying value $ 16,112 |
Related Party Transactions (Tab
Related Party Transactions (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
BridgeBio Pharma LLC | |
Related Party Transaction [Line Items] | |
Schedule of Benefits and Expenses from Transactions with Related Party | The Company incurred the following expenses under the applicable services agreement with BBP LLC (in thousands): Year Ended December 31, 2019 2018 2017 Rent $ (54 ) $ 39 $ 76 Facility — 121 65 Consulting 573 999 656 $ 519 $ 1,159 $ 797 |
Founders | |
Related Party Transaction [Line Items] | |
Schedule of Benefits and Expenses from Transactions with Related Party | The Company incurred the following research and development expenses for services under these consulting agreements and stock-based compensation (in thousands): Year Ended December 31, 2019 2018 2017 Dr. Graef $ 150 $ 150 $ 279 Dr. Alhamadsheh 115 115 244 $ 265 $ 265 $ 523 |
Redeemable Convertible Prefer_3
Redeemable Convertible Preferred Stock (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Temporary Equity Disclosure [Abstract] | |
Schedule of Redeemable Convertible Preferred Stock | The table below provides information on the Company’s redeemable convertible preferred stock as of December 31, 2017 (in thousands, except shares and original issue price ): Proceeds, net of Liquidation Shares Shares Price issuance cost amount Series authorized outstanding per share (in thousands) (in thousands) Seed 14,000,000 12,856,325 $ 1.3248 $ 16,920 $ 17,032 |
Stockholders' Equity and Stoc_2
Stockholders' Equity and Stock-Based Compensation (Tables) | 12 Months Ended |
Dec. 31, 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: December 31, 2019 2018 2017 Redeemable convertible preferred stock outstanding, as converted — — 15,376,164 Options issued and outstanding 1,335,755 1,329,762 846,166 Options available for future grants 1,935,054 747,057 670,994 ESPP shares available for future grants 97,805 130,166 — 3,368,614 2,206,985 16,893,324 |
Summary of Stock Option Activity | Activity under the Company’s equity incentive plans is set forth below: 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 Additional authorized 1,500,000 — $ - Options granted (365,573 ) 365,573 $ 34.51 Options exercised — (306,010 ) $ 3.30 Options cancelled 53,570 (53,570 ) $ 7.24 Outstanding—December 31, 2019 1,935,054 1,335,755 $ 16.91 8.77 $ 54,071 Options exercisable – December 31, 2019 241,289 $ 11.16 8.50 $ 11,155 Options vested and expected to vest – December 31, 2019 1,335,755 $ 16.91 8.77 $ 54,071 |
Schedule of Total Stock-based Compensation Expense Related to Stock-based Awards | Total stock-based compensation expense related to all the Company’s stock-based awards was recorded on the statements of operations as follows (in thousands): Year Ended December 31, 2019 2018 2017 Research and development $ 2,313 $ 1,325 $ 519 General and administrative $ 3,060 1,201 629 Total stock-based compensation expense $ 5,373 $ 2,526 $ 1,148 Year Ended December 31, 2019 2018 2017 Stock option expense $ 5,198 $ 2,404 $ 1,148 Employee Stock Plan 175 122 — Total stock-based compensation expense $ 5,373 $ 2,526 $ 1,148 |
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: Year Ended December 31, 2019 2018 2017 Expected term in years 6.07 6.08 5.83 Expected volatility 72.39 % 71.99 % 68.40 % Risk-free interest rate 1.95 % 2.87 % 2.27 % Dividend yield 0 % 0 % 0 % Weighted average fair value of share-based awards granted $ 22.86 $ 8.46 $ 4.79 |
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 using the Black-Scholes option-pricing model with the following assumptions: Year Ended December 31, 2019 2018 2017 Expected term in years 6.09 9.20 9.66 Expected volatility 73.67 % 73.87 % 80.08 % Risk-free interest rate 2.49 % 2.66 % 2.41 % Dividend yield 0 % 0 % 0 % |
2018 Employee Stock Purchase Plan | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
Summary of Fair Value of Rights Granted | The fair value of the rights granted under the 2018 ESPP was calculated using the Black-Scholes option-pricing model with the following assumptions: Year Ended December 31, Year Ended December 31, 2019 2018 Expected term in years 0.50 0.48 Expected volatility 63.06 % 70.40 % Risk-free interest rate 2.32 % 1.50 % Dividend yield 0 % 0 % |
Income taxes (Tables)
Income taxes (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Income Tax Disclosure [Abstract] | |
Summary of Effective Tax Rate Differs from Federal Statutory Rate | The effective tax rate differs from the federal statutory rate as follows: Year Ended December 31, 2019 2018 2017 Federal statutory income tax rate 21.0 % 21.0 % 34.0 % State income taxes 0.0 % 0.0 % 0.0 % Federal rate change impact due to Tax Act 0.0 % 0.0 % -13.4 % Research and development credits 15.5 % 3.2 % 1.5 % Stock-based compensation 2.5 % -1.5 % -1.5 % Change in fair value of convertible note 0.0 % -1.6 % 0.2 % Other 2.6 % -1.3 % -0.7 % Change in valuation allowance -41.6 % -19.8 % -20.1 % 0.00 % 0.00 % 0.00 % |
Schedule of Deferred Tax Assets | Year Ended December 31, 2019 2018 Deferred tax assets: Net operating loss carryforward $ 20,925 $ 13,046 Research and development credits 9,415 1,680 Stock-based compensation 328 — Lease liability 1,080 — Other 23 37 Deferred tax assets before valuation allowance 31,771 14,763 Less: valuation allowance (30,727 ) (14,566 ) Net deferred income tax assets 1,044 197 Deferred tax liabilities: Stock-based compensation — (197 ) Right of use assets (842 ) — Fixed assets (202 ) — Net deferred tax assets (liabilities) $ — $ — |
Reconciliation of Unrecognized Tax Benefits | A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Year Ended December 31, 2019 2018 2017 Balance at beginning of year $ 525 $ 166 $ 31 Additions based on tax positions related to current year 1,217 359 135 Balance at end of year $ 1,742 $ 525 $ 166 |
Net loss per Share (Tables)
Net loss per Share (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Earnings Per Share [Abstract] | |
Schedule of Earnings Per Share | December 31, 2019 2018 2017 Numerator: Net loss attributable to common stockholders $ (37,835 ) $ (39,812 ) $ (11,941 ) Denominator: Weighted average common shares outstanding 37,114,930 22,037,363 4,324,525 Weighted average unvested common shares subject to repurchase (490,238 ) (670,368 ) (727,852 ) Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted 36,624,692 21,366,995 3,596,673 Net loss per share attributable to common stockholders, basic and diluted $ (1.03 ) $ (1.86 ) $ (3.32 ) |
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 years ended December 31, 2019, 2018 and 2017 because their inclusion would be anti-dilutive: December 31, 2019 2018 2017 Redeemable convertible preferred stock on an as-converted basis — — 15,376,164 ESPP shares 1,318 5,115 — Options to purchase common stock 1,335,755 1,329,762 846,163 Common stock subject to vesting or repurchase 353,647 627,530 828,843 1,690,720 1,962,407 17,051,170 |
Commitments and Contingencies (
Commitments and Contingencies (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Commitments And Contingencies Disclosure [Abstract] | |
Schedule of Other Information of Operating Lease | Other information related to the operating lease: Year Ended December 31, 2019 Cash payments over lease term (in thousands) $ 6,296 Weighted average remaining lease term (months) 82 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 December 31, 2019 are as follows (in thousands): Operating Year Lease Commitments 2020 $ 844 2021 869 2022 896 2023 922 2024 950 Thereafter 1,815 $ 6,296 |
Supplementary Financial Data _2
Supplementary Financial Data (Unaudited) (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Quarterly Financial Information Disclosure [Abstract] | |
Schedule of Selected Quarterly Financial Data | The following table presents the selected quarterly financial data for the years ended December 31, 2019 and 2018: Statements of Operations Quarter Ended March 31 June 30 September 30 December 31 (In thousands, except per share amounts) 2019 Income (loss) from operations $ (12,584 ) $ (14,794 ) $ 6,251 $ (19,324 ) Net income (loss) attributable to common stockholders $ (11,733 ) $ (14,053 ) $ 6,931 $ (18,980 ) Net income (loss) per share of common stock attributable to common stockholders, basic $ (0.32 ) $ (0.39 ) $ 0.19 $ (0.51 ) Net income (loss) per share of common stock attributable to common stockholders, diluted $ (0.32 ) $ (0.39 ) $ 0.18 $ (0.51 ) 2018 Loss from operations $ (7,997 ) $ (8,089 ) $ (10,988 ) $ (10,705 ) Net loss attributable to common stockholders $ (7,963 ) $ (11,381 ) $ (10,614 ) $ (9,854 ) Net loss per share of common stock attributable to common stockholders, basic and diluted $ (1.81 ) $ (1.40 ) $ (0.30 ) $ (0.27 ) |
Organization and Description _2
Organization and Description of Business - Additional Information (Details) | Aug. 02, 2019USD ($) | Jun. 22, 2018USD ($)$ / sharesshares | Dec. 31, 2019USD ($)Segmentshares | Dec. 31, 2018USD ($)shares |
Organization And Description Of Business [Line Items] | ||||
Entity date of incorporation | Aug. 6, 2013 | |||
Entity incorporation, State | DE | |||
Number of operating segment | Segment | 1 | |||
Proceeds from issuance of initial public offering, net of underwriting discounts and commissions | $ | $ 110,970,000 | |||
Accumulated deficit | $ | $ (103,105,000) | $ (65,270,000) | ||
Open Market Sale Agreement | ||||
Organization And Description Of Business [Line Items] | ||||
Number of shares issued | shares | 385,613 | |||
Maximum aggregate sales price of shares to be issued under open market sale agreement | $ | $ 100,000,000 | |||
Agency commission as percentage from proceeds from sale of common stock gross | 3.00% | |||
Proceeds from the issuance of common stock | $ | $ 23,900,000 | |||
Open Market Sale Agreement | Maximum | ||||
Organization And Description Of Business [Line Items] | ||||
Agency commission as percentage from proceeds from sale of common stock gross | 3.00% | |||
Common Stock | ||||
Organization And Description Of Business [Line Items] | ||||
Number of shares issued | shares | 7,187,500 | |||
Proceeds from issuance of initial public offering, net of underwriting discounts and commissions | $ | $ 111,000,000 | |||
Initial Public Offering | Common Stock | ||||
Organization And Description Of Business [Line Items] | ||||
Number of shares issued | shares | 7,187,500 | |||
Shares issued price per share | $ / shares | $ 17 | |||
Redeemable convertible preferred stock and warrants converted to common stock | shares | 24,231,517 | |||
Overallotment Option | Common Stock | ||||
Organization And Description Of Business [Line Items] | ||||
Number of shares issued | shares | 937,500 |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) | 12 Months Ended | |||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Summary of Significant Accounting Policies [Line Items] | ||||
Impairment of long-lived assets | $ 0 | |||
Liabilities outstanding | $ 0 | $ 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 | $ 6,500,000 | 6,523,000 | ||
Recognized income tax positions | Recognized income tax positions are measured at the largest amount that has a greater than 50% likelihood of being realized. | |||
Unrecognized tax benefits | $ 1,742,000 | $ 525,000 | $ 166,000 | $ 31,000 |
Interest and Penalties | ||||
Summary of Significant Accounting Policies [Line Items] | ||||
Unrecognized tax benefits | 0 | |||
Loan payment prior to November 13, 2021 | SVB and Hercules Loan Agreement | ||||
Summary of Significant Accounting Policies [Line Items] | ||||
Success Fee amount | 1,000,000 | |||
Loan payment after November 19, 2021 | SVB and Hercules Loan Agreement | ||||
Summary of Significant Accounting Policies [Line Items] | ||||
Success Fee amount | $ 2,000,000 | |||
Minimum | ||||
Summary of Significant Accounting Policies [Line Items] | ||||
Property, plant and equipment useful life | 3 years | |||
Maximum | ||||
Summary of Significant Accounting Policies [Line Items] | ||||
Property, plant and equipment useful life | 5 years |
Fair Value Measurements - Addit
Fair Value Measurements - Additional Information (Details) - USD ($) | 12 Months Ended | |
Dec. 31, 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 | |
Fair value liabilities, level 2 to level 1 transfers, amount | 0 | |
Fair value liabilities transfers into Level 3 | 0 | |
Fair value liabilities transfers out of Level 3 | $ 0 |
Fair Value Measurements - Sched
Fair Value Measurements - Schedule of Fair Value of Financial Assets (Details) $ in Thousands | Dec. 31, 2019USD ($) |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |
Fair value of financial assets | $ 191,157 |
Fair value of financial liabilities | 1,165 |
Money Market Funds [Member] | |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |
Fair value of financial assets | 191,157 |
Embedded Derivative [Member] | |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |
Fair value of financial liabilities | 1,165 |
Level I | |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |
Fair value of financial assets | 191,157 |
Level I | Money Market Funds [Member] | |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |
Fair value of financial assets | 191,157 |
Level III | |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |
Fair value of financial liabilities | 1,165 |
Level III | Embedded Derivative [Member] | |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | |
Fair value of financial liabilities | $ 1,165 |
Fair Value Measurements - Summa
Fair Value Measurements - Summary of Redeemable Convertible Preferred Stock Tranche Liability (Details) - Fair Value, Measurements, Recurring - Redeemable Convertible Preferred Stock Tranche Liability - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Redeemable convertible preferred stock tranche/warrant liability: | ||
Beginning balance | $ 315 | |
Issuance of Series B redeemable convertible preferred stock tranche liability | $ 64 | |
Change in fair value upon revaluation recognized in other income (expense), net | 630 | (75) |
Settlement of redeemable convertible preferred stock tranche liability due to the issuance of redeemable convertible preferred stock | $ (694) | $ (240) |
Fair Value Measurements - Sum_2
Fair Value Measurements - Summary of Redeemable Convertible Preferred Stock Warrant Liability (Details) - Fair Value, Measurements, Recurring - Redeemable Convertible Preferred Stock Warrant Liability $ in Thousands | 12 Months Ended |
Dec. 31, 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) |
Fair Value Measurements - Sum_3
Fair Value Measurements - Summary of Embedded Derivative in Convertible Note (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended |
Mar. 31, 2018 | Dec. 31, 2018 | |
Derivative instrument: | ||
Settlement of the embedded derivative liability | $ (6,500) | |
Convertible Promissory Notes Payable | ||
Derivative instrument: | ||
Embedded derivative liability, valuation technique [extensible list] | us-gaap:ValuationTechniqueDiscountedCashFlowMember | |
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) |
Fair Value Measurements - Sum_4
Fair Value Measurements - Summary of Embedded Derivative in Loan Payable (Details) - Loan Payable $ in Thousands | 12 Months Ended |
Dec. 31, 2019USD ($) | |
Derivative instrument: | |
Embedded derivative liability, valuation technique [extensible list] | us-gaap:ValuationTechniqueDiscountedCashFlowMember |
Initial fair value of the embedded derivative liability issued with the Loan payable | $ 1,148 |
Change in fair value upon revaluation recognized in other income (expense), net | 17 |
Ending balance | $ 1,165 |
Balance Sheet Components - Sche
Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Property Plant And Equipment [Line Items] | ||
Total property and equipment, cost | $ 1,360 | $ 269 |
Less: accumulated depreciation and amortization | (101) | (60) |
Total property and equipment, net | 1,259 | 209 |
Leasehold Improvements | ||
Property Plant And Equipment [Line Items] | ||
Total property and equipment, cost | 1,112 | 86 |
Computer Equipment | ||
Property Plant And Equipment [Line Items] | ||
Total property and equipment, cost | 139 | 87 |
Office Furniture and Equipment | ||
Property Plant And Equipment [Line Items] | ||
Total property and equipment, cost | $ 109 | $ 96 |
Balance Sheet Components - Addi
Balance Sheet Components - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Condensed Balance Sheet Components [Line Items] | |||
Depreciation and amortization | $ 77 | $ 56 | $ 4 |
Other Liabilities | |||
Condensed Balance Sheet Components [Line Items] | |||
Other liabilities related to long-term liability for unvested stock | $ 95 | $ 244 |
Balance Sheet Components - Sc_2
Balance Sheet Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Accrued Liabilities And Other Liabilities [Abstract] | ||
Accrued research and development costs | $ 3,968 | $ 2,055 |
Accrued employee related expenses | 1,865 | 78 |
Liability for unvested stock, short-term | 143 | 142 |
Accrued other current liabilities | 433 | 302 |
Total accrued expenses and other current liabilities | $ 6,409 | $ 2,577 |
Balance Sheet Components - Sc_3
Balance Sheet Components - Schedule of Lease Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Mar. 27, 2019 |
Balance Sheet Related Disclosures [Abstract] | ||
Lease liabilities, current | $ 554 | |
Lease liabilities, non-current | 4,591 | |
Total lease liabilities | $ 5,145 | $ 1,000 |
Debt Obligations - Additional I
Debt Obligations - Additional Information (Details) | Nov. 13, 2019USD ($)Tranche | Mar. 31, 2018USD ($)shares$ / shares | Feb. 28, 2018USD ($)ConvertiblePromissoryNote$ / shares | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) |
Short Term Debt [Line Items] | |||||
Fair value of embedded derivative liability settled | $ 6,500,000 | ||||
Extinguishment of Debt, Amount | 14,400,000 | ||||
Carrying value of debt | $ 16,112,000,000 | ||||
Discounts and debt issuance cost on debt issuance | 2,430,000,000 | ||||
Change in fair value of derivative liability | (17,000) | $ 100,000 | |||
SVB and Hercules Loan Agreement | |||||
Short Term Debt [Line Items] | |||||
Fair value of embedded derivative liability | 1,100,000 | ||||
Additional withdrawn of term loan | 0 | ||||
Fair value of derivative liability | 1,200,000 | ||||
Change in fair value of derivative liability | $ 17,000 | ||||
SVB and Hercules Loan Agreement | Discount Rate | |||||
Short Term Debt [Line Items] | |||||
Discount rate | 0.116 | ||||
SVB and Hercules Loan Agreement | Term Loan | |||||
Short Term Debt [Line Items] | |||||
Term loan facility, maximum borrowing capacity | $ 55,000,000 | ||||
Number of tranches of term loan | Tranche | 3 | ||||
SVB and Hercules Loan Agreement | Tranche A Loan | |||||
Short Term Debt [Line Items] | |||||
Debt instrument, annual interest rate | 8.50% | ||||
Term loan facility, maximum borrowing capacity | $ 17,500,000 | ||||
Date of withdrawn of term loan | Nov. 13, 2019 | ||||
Commitment fee | $ 300,000 | $ 300,000 | |||
Final payment, percent of principal | 5.95% | ||||
Carrying value of debt | 16,100,000 | ||||
Discounts and debt issuance cost on debt issuance | 2,500,000 | ||||
Discounts related to recognition of bifurcated compound embedded derivative liability | 1,100,000 | ||||
Discounts related to final payment charge | 1,000,000 | ||||
Prepayment of loan | 100,000 | ||||
SVB and Hercules Loan Agreement | Tranche A Loan | Prime Rate | |||||
Short Term Debt [Line Items] | |||||
Debt instrument interest rate | 3.25% | ||||
SVB and Hercules Loan Agreement | Tranche B Loan | |||||
Short Term Debt [Line Items] | |||||
Term loan facility, maximum borrowing capacity | $ 22,500,000 | ||||
Date of withdrawn of term loan | Oct. 31, 2020 | ||||
SVB and Hercules Loan Agreement | Tranche C Loan | |||||
Short Term Debt [Line Items] | |||||
Term loan facility, maximum borrowing capacity | $ 15,000,000 | ||||
Date of withdrawn of term loan | Sep. 30, 2021 | ||||
SVB and Hercules Loan Agreement | Tranche A Term Loan | |||||
Short Term Debt [Line Items] | |||||
Interest Expense | $ 300,000 | ||||
Carrying value of debt | 16,100,000 | ||||
Discounts and debt issuance cost on debt issuance | 2,400,000 | ||||
Loan payment prior to November 13, 2021 | SVB and Hercules Loan Agreement | |||||
Short Term Debt [Line Items] | |||||
Success Fee amount | 1,000,000 | ||||
Loan payment after November 19, 2021 | SVB and Hercules Loan Agreement | |||||
Short Term Debt [Line Items] | |||||
Success Fee amount | $ 2,000,000 | ||||
BBP LLC and Stanford University | Note and Warrant Purchase Agreement | |||||
Short Term Debt [Line Items] | |||||
Number of convertible promissory notes issued | ConvertiblePromissoryNote | 2 | ||||
Minimum | SVB and Hercules Loan Agreement | Tranche A Loan | |||||
Short Term Debt [Line Items] | |||||
Term loan prepayment fee percentage | 0.75% | ||||
Maximum | SVB and Hercules Loan Agreement | Tranche A Loan | |||||
Short Term Debt [Line Items] | |||||
Term loan prepayment fee percentage | 2.50% | ||||
Convertible Promissory Notes | |||||
Short Term Debt [Line Items] | |||||
Outstanding principal and accrued interest | 10,000,000 | ||||
Gain on extinguishment of debt | $ 7,400,000 | ||||
Convertible Promissory Notes | BBP LLC and Stanford University | Note and Warrant Purchase Agreement | |||||
Short Term Debt [Line Items] | |||||
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% | ||||
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 | 1,000,000 | ||||
Fair value of embedded derivative liability | 6,500,000 | ||||
Convertible Promissory Notes | Minimum | BBP LLC and Stanford University | Note and Warrant Purchase Agreement | |||||
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 | ||||
Series Seed Redeemable Convertible Preferred Stock | BBP LLC and Stanford University | Note and Warrant Purchase Agreement | |||||
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 | ||||
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 Price1 | $ / 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 |
Debt Obligations - Schedule of
Debt Obligations - Schedule of Future Minimum Payments (Details) $ in Millions | Dec. 31, 2019USD ($) |
Debt Disclosure [Abstract] | |
2020 | $ 1,512 |
2021 | 2,961 |
2022 | 9,787 |
2023 | 8,622 |
Total | 22,882 |
Less: amount representing interest | (4,340) |
Less: unamortized debt discount associated with the issuance of a compound embedded derivative liability, final payment charge and other debt issuance costs | (2,430) |
Total carrying value | $ 16,112 |
Related Party Transactions - Ad
Related Party Transactions - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended | ||||
May 31, 2018 | Sep. 30, 2017 | Aug. 31, 2016 | Apr. 30, 2016 | Dec. 31, 2019 | Dec. 31, 2018 | |
Related Party Transaction [Line Items] | ||||||
Number of options granted | 365,573 | |||||
2018 Plan | Dr. Huh | ||||||
Related Party Transaction [Line Items] | ||||||
Number of options granted | 83,720 | |||||
Option vesting period | 3 years | |||||
2018 Plan | Dr. Huh | Director Service | ||||||
Related Party Transaction [Line Items] | ||||||
Number of options granted | 43,056 | |||||
2018 Plan | Dr. Huh | Consulting Service | ||||||
Related Party Transaction [Line Items] | ||||||
Number of options granted | 40,664 | |||||
Dr. Graef Consulting Agreement | ||||||
Related Party Transaction [Line Items] | ||||||
Consulting agreement term | 4 years | |||||
Consulting agreement termination notice period | 30 days | |||||
Issue of shares of common stock | 195,273 | |||||
Gross-up payment due to related party | $ 83,073 | |||||
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 | |||||
Issue of shares of common stock | 195,273 | |||||
Gross-up payment due to related party | $ 83,073 | |||||
Dr. Alhamadsheh Consulting Agreement | Maximum | ||||||
Related Party Transaction [Line Items] | ||||||
Annual fee amount | $ 115,000 | |||||
BridgeBio Pharma, Inc | ||||||
Related Party Transaction [Line Items] | ||||||
Outstanding receivable | $ 85,000 | $ 34,000 | ||||
Outstanding liability | $ 300,000 | $ 200,000 | ||||
BridgeBio Pharma, Inc | ||||||
Related Party Transaction [Line Items] | ||||||
Ownership percentage | 64.60% | 61.00% |
Related Party Transactions - Sc
Related Party Transactions - Schedule of Benefits and Expenses from Transactions with Related Party (Details) - BridgeBio Pharma, Inc - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Related Party Transaction [Line Items] | |||
Related party transaction expenses | $ 519 | $ 1,159 | $ 797 |
Rent | |||
Related Party Transaction [Line Items] | |||
Related party transaction expenses | (54) | 39 | 76 |
Facility | |||
Related Party Transaction [Line Items] | |||
Related party transaction expenses | 121 | 65 | |
Consulting | |||
Related Party Transaction [Line Items] | |||
Related party transaction expenses | $ 573 | $ 999 | $ 656 |
Related Party Transactions - _2
Related Party Transactions - Schedule of Expenses (Benefit) for Services under Consulting Agreements and Stock-Based Compensation (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Dr. Graef | |||
Related Party Transaction [Line Items] | |||
Related party transaction expenses (benefit) | $ 150 | $ 150 | $ 279 |
Dr. Alhamadsheh | |||
Related Party Transaction [Line Items] | |||
Related party transaction expenses (benefit) | 115 | 115 | 244 |
Founders | |||
Related Party Transaction [Line Items] | |||
Related party transaction expenses (benefit) | $ 265 | $ 265 | $ 523 |
Redeemable Convertible Prefer_4
Redeemable Convertible Preferred Stock - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | Mar. 29, 2018 | May 31, 2018 | Mar. 31, 2018 | Sep. 30, 2017 | Mar. 31, 2017 | Sep. 30, 2016 | Apr. 30, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2019 | Jun. 22, 2018 | Dec. 31, 2016 |
Temporary Equity [Line Items] | ||||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 63,875 | $ 12,993 | ||||||||||
Fair value of financial liabilities | $ 1,165 | |||||||||||
Number of common stock issued upon conversion of redeemable convertible preferred stock | 24,025,270 | |||||||||||
Redeemable convertible preferred stock, shares outstanding | 12,856,325 | 0 | 3,043,525 | |||||||||
Series Seed Redeemable Convertible Preferred Stock | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 9,000 | $ 8,000 | $ 16,920 | |||||||||
Redeemable convertible preferred stock issued | 6,793,477 | 24,202 | 9,812,800 | |||||||||
Conversion of notes payable, derivative liability and accrued interest | 32,000 | |||||||||||
Redeemable convertible preferred stock, shares outstanding | 12,856,325 | |||||||||||
Series Seed Redeemable Convertible Preferred Stock | First Tranche | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 1,000 | |||||||||||
Redeemable convertible preferred stock issued | 754,831 | |||||||||||
Series Seed Redeemable Convertible Preferred Stock | Second Tranche | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 3,000 | |||||||||||
Redeemable convertible preferred stock issued | 2,264,492 | |||||||||||
Series Seed Redeemable Convertible Preferred Stock | Third Tranche | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 4,000 | |||||||||||
Redeemable convertible preferred stock issued | 3,019,323 | |||||||||||
Series B Redeemable Convertible Preferred Stock | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 16,000 | $ 48,000 | $ 16,000 | |||||||||
Redeemable convertible preferred stock issued | 4,430,162 | 1,476,715 | 4,430,162 | |||||||||
Additional redeemable convertible preferred stock issuable | 4,430,162 | |||||||||||
Fair value of financial liabilities | $ 700 | $ 100 | ||||||||||
Redeemable convertible preferred stock purchase price per share | $ 10.8348 | $ 10.8348 |
Redeemable Convertible Prefer_5
Redeemable Convertible Preferred Stock - Schedule of Redeemable Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 12 Months Ended | ||||
Sep. 30, 2017 | Apr. 30, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2016 | |
Temporary Equity [Line Items] | ||||||
Shares outstanding | 12,856,325 | 0 | 3,043,525 | |||
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs | $ 63,875 | $ 12,993 | ||||
Series Seed Redeemable Convertible Preferred Stock | ||||||
Temporary Equity [Line Items] | ||||||
Shares authorized | 14,000,000 | |||||
Shares outstanding | 12,856,325 | |||||
Price per share | $ 1.3248 | |||||
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs | $ 9,000 | $ 8,000 | $ 16,920 | |||
Liquidation amount | $ 17,032 |
Redeemable Convertible Prefer_6
Redeemable Convertible Preferred Stock Tranche Liabilities - Additional Information (Details) - USD ($) | Mar. 29, 2018 | Apr. 04, 2016 | May 31, 2018 | Mar. 31, 2018 | Mar. 31, 2017 | Sep. 30, 2016 | Apr. 30, 2016 | Sep. 07, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2019 |
Temporary Equity [Line Items] | ||||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 63,875,000 | $ 12,993,000 | ||||||||||
Shares issued upon conversion of outstanding convertible promissory note | 1,324,823 | |||||||||||
Conversion of convertible promissory note principal balance | $ 10,000,000 | |||||||||||
Fair value of financial liabilities | $ 1,165,000 | |||||||||||
Settlement of fair value of redeemable convertible preferred stock liability | $ 700,000 | $ 200,000 | ||||||||||
Black-Scholes Option Pricing Model | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset equity value assumptions | $ 2,100,000 | |||||||||||
Term | Black-Scholes Option Pricing Model | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input, term | 29 days | 3 years | ||||||||||
Risk-Free Interest Rate | Black-Scholes Option Pricing Model | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input | 1.63% | 0.92% | ||||||||||
Volatility | Black-Scholes Option Pricing Model | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input | 36.40% | 75.00% | ||||||||||
Dividend Yield | Black-Scholes Option Pricing Model | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input | 0.00% | 0.00% | ||||||||||
Maximum | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Redeemable convertible preferred stock issued | 5,283,815 | |||||||||||
Tranche Liability for Third Milestone | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Fair value of financial liabilities | $ 200,000 | |||||||||||
Preferred stock liability and put option asset equity value assumptions | $ 4,000,000 | $ 4,000,000 | ||||||||||
Change in fair value of convertible preferred stock | $ 300,000 | |||||||||||
Tranche Liability for Third Milestone | Term | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input, term | 2 years 3 months 18 days | 2 years 6 months | ||||||||||
Tranche Liability for Third Milestone | Risk-Free Interest Rate | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input | 1.40% | 1.34% | ||||||||||
Tranche Liability for Third Milestone | Volatility | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input | 70.00% | 76.00% | ||||||||||
Tranche Liability for Third Milestone | Dividend Yield | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Preferred stock liability and put option asset, fair value assumptions, measurement input | 0.00% | 0.00% | ||||||||||
Tranche Liability for Second Milestone | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Fair value of financial liabilities | $ 100,000 | |||||||||||
Settlement of fair value of redeemable convertible preferred stock liability | $ 100,000 | |||||||||||
Series Seed Preferred Stock | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Shares issued price per share | $ 1.3248 | |||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 1,000,000 | |||||||||||
Shares issued upon conversion of outstanding convertible promissory note | 24,202 | |||||||||||
Conversion of convertible promissory note principal balance | $ 26,000 | |||||||||||
Redeemable convertible preferred stock purchase price per share | $ 1.3248 | |||||||||||
Series Seed Preferred Stock | Maximum | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Redeemable convertible preferred stock issued | 754,831 | 6,062,848 | ||||||||||
Series Seed Preferred Stock | Second Tranche | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Redeemable convertible preferred stock issued | 2,264,492 | |||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 3,000,000 | |||||||||||
Series Seed Preferred Stock | Third Tranche | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Redeemable convertible preferred stock issued | 3,019,323 | |||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 4,000,000 | |||||||||||
Series Seed Tranche Liability | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Fair value of financial liabilities | $ 300,000 | |||||||||||
Series B Redeemable Convertible Preferred Stock | ||||||||||||
Temporary Equity [Line Items] | ||||||||||||
Redeemable convertible preferred stock issued | 4,430,162 | 1,476,715 | 4,430,162 | |||||||||
Shares issued price per share | $ 10.8348 | $ 10.8348 | ||||||||||
Proceeds from issuance of redeemable convertible preferred stock | $ 16,000,000 | $ 48,000,000 | $ 16,000,000 | |||||||||
Fair value of financial liabilities | $ 700,000 | $ 100,000 | ||||||||||
Redeemable convertible preferred stock purchase price per share | $ 10.8348 | $ 10.8348 | ||||||||||
Additional shares issuable upon achievement of certain milestone | 4,430,162 | |||||||||||
Remeasurement of redeemable convertible preferred stock liability | $ 700,000 | |||||||||||
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 | $ 14,400,000 | |||||||||||
Fair value of financial liabilities | $ 100,000 |
Stockholders' Equity and Stoc_3
Stockholders' Equity and Stock-Based Compensation - Summary of Reserved Shares of Common Stock for Issuance (Details) - shares | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
Common stock reserved for issuance | 3,368,614 | 2,206,985 | 16,893,324 |
Redeemable Convertible Preferred Stock Outstanding, as Converted | |||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
Common stock reserved for issuance | 15,376,164 | ||
Options Issued and Outstanding | |||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
Common stock reserved for issuance | 1,335,755 | 1,329,762 | 846,166 |
Options Available for Future Grants | |||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
Common stock reserved for issuance | 1,935,054 | 747,057 | 670,994 |
ESPP Shares Available for Future Grants | |||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
Common stock reserved for issuance | 97,805 | 130,166 |
Stockholders' Equity and Stoc_4
Stockholders' Equity and Stock-Based Compensation - Additional Information (Details) - USD ($) | Aug. 02, 2019 | May 31, 2018 | Dec. 31, 2017 | Apr. 30, 2016 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Common stock reserved for issuance | 16,893,324 | 3,368,614 | 2,206,985 | 16,893,324 | |||
Total intrinsic value of options exercised | $ 12,300,000 | $ 900,000 | |||||
Total fair value of shares vested | 5,200,000 | 2,500,000 | |||||
Expected dividend yield | $ 0 | ||||||
Number of options granted | 365,573 | ||||||
Stock-based compensation expense | $ 5,373,000 | $ 2,526,000 | $ 1,148,000 | ||||
Stock repurchase right | 524,513 | 896,034 | |||||
Common stock, shares outstanding | 38,040,693 | 36,760,536 | |||||
Accrued Expenses and Other Current Liabilities | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Accrued repurchase liability for common stock early exercises | $ 238,000 | $ 386,000 | |||||
Non Employees | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Number of options granted | 20,361 | 35,880 | 569,252 | ||||
Stock-based compensation expense | $ 100,000 | $ 1,700,000 | $ 700,000 | ||||
Restricted Stock | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Issuance of common stock to founders in connection with anti-dilution rights | 390,546 | ||||||
Consideration for common stock to founders in connection with anti-dilution rights | $ 0 | ||||||
Percentage of shares issued under license agreement to issue additional common stock | 1.00% | ||||||
Percentage of right lapses as shares vest | 25.00% | ||||||
Common stock, shares outstanding | 170,866 | 268,504 | |||||
Share-based compensation (benefit) expense | $ 0 | $ 0 | $ 200,000 | ||||
Annual Cliff Vesting | Restricted Stock | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Vesting period of right lapses | 1 year | ||||||
Tranche Liability for Second Milestone | Restricted Stock | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Vesting period of right lapses | 36 months | ||||||
2016 Equity Incentive Plan | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Term of options | 10 years | ||||||
2016 Equity Incentive Plan | Incentive Stock Options | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Percentage of exercise price of stock option granted to employee | 10.00% | ||||||
2016 Equity Incentive Plan | Minimum | Incentive Stock Options and Nonqualified Stock Options | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Percentage of exercise price of stock option on estimated fair value of shares | 100.00% | ||||||
2016 Equity Incentive Plan | Minimum | Incentive Stock Options | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Percentage of exercise price of stock option on estimated fair value of shares | 110.00% | ||||||
2016 Equity Incentive Plan | Annual Cliff Vesting | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Vesting period of options | 4 years | ||||||
2016 Equity Incentive Plan | Tranche Liability for Second Milestone | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Vesting period of options | 36 months | ||||||
Amended and Restated 2018 Stock Option and Incentive Plan | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Vesting period of options | 3 years | ||||||
Common stock reserved for issuance | 598,000 | 2,798,000 | |||||
Minimum combined voting power require to grant options | 10.00% | ||||||
Increase in number of shares reserved | 1,500,000 | 700,000 | |||||
Amended and Restated 2018 Stock Option and Incentive Plan | Stockholders Possessing more than 10% | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Term of options | 10 years | ||||||
Amended and Restated 2018 Stock Option and Incentive Plan | Minimum | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Percentage of exercise price of stock option on estimated fair value of shares | 100.00% | ||||||
Amended and Restated 2018 Stock Option and Incentive Plan | Minimum | Stockholders Possessing more than 10% | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Percentage of exercise price of stock option on estimated fair value of shares | 110.00% | ||||||
Amended and Restated 2018 Stock Option and Incentive Plan | Maximum | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Term of options | 10 years | ||||||
Amended and Restated 2018 Stock Option and Incentive Plan | Annual Cliff Vesting | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Employee stock options vesting percentage | 25.00% | ||||||
2018 Employee Stock Purchase Plan | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Percentage of exercise price of stock option on estimated fair value of shares | 85.00% | ||||||
Common stock reserved for issuance | 143,520 | ||||||
Percentage of compensation of eligible employees to purchase shares of common stock at discount through payroll deductions | 20.00% | ||||||
2016 and 2018 Plans | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Unrecognized stock-based compensation cost related to unvested stock | $ 13,500,000 | ||||||
Unrecognized stock-based compensation cost, to be recognized weighted-average period | 2 years 10 months 24 days | ||||||
Open Market Sale Agreement | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Maximum aggregate sales price of shares to be issued under open market sale agreement | $ 100,000,000 | ||||||
Agency commission as percentage from proceeds from sale of common stock gross | 3.00% | ||||||
Issuance of common stock upon initial public offering, net of issuance costs, Shares | 385,613 | ||||||
Proceeds from the issuance of common stock | $ 23,900,000 | ||||||
Open Market Sale Agreement | Maximum | |||||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||||
Agency commission as percentage from proceeds from sale of common stock gross | 3.00% |
Stockholders' Equity and Stoc_5
Stockholders' Equity and Stock-Based Compensation - Summary of Fair Value of Rights Granted (Details) - 2018 Employee Stock Purchase Plan | 12 Months Ended | |
Dec. 31, 2019 | Dec. 31, 2018 | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Expected term in years | 6 months | 5 months 23 days |
Expected volatility | 63.06% | 70.40% |
Risk-free interest rate | 2.32% | 1.50% |
Dividend yield | 0.00% | 0.00% |
Stockholders' Equity and Stoc_6
Stockholders' Equity and Stock-Based Compensation - Summary of Stock Options Activity Under Equity Incentive Plans (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended | |
Dec. 31, 2019 | Dec. 31, 2018 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||
Options Available for Grant, Outstanding, Beginning balance | 747,057 | |
Options Available for Grant, Additional authorized | 1,500,000 | |
Options Available for Grant, Options granted | (365,573) | |
Options Available for Grant, Options cancelled | 53,570 | |
Options Available for Grant, Outstanding, Ending balance | 1,935,054 | 747,057 |
Options Outstanding, Beginning balance | 1,329,762 | |
Options Outstanding, Options granted | 365,573 | |
Options Outstanding, Options exercised | (306,010) | |
Options Outstanding, Options cancelled | (53,570) | |
Options Outstanding, Ending balance | 1,335,755 | 1,329,762 |
Options Outstanding, Options exercisable | 241,289 | |
Options Outstanding, Options vested and expected to vest | 1,335,755 | |
Weighted-Average Exercise Price Per Share, Beginning balance | $ 8.55 | |
Weighted-Average Exercise Price Per Share, Options granted | 34.51 | |
Weighted-Average Exercise Price Per Share, Options Exercised | 3.30 | |
Weighted-Average Exercise Price Per Share, Options Cancelled | 7.24 | |
Weighted-Average Exercise Price Per Share, Ending balance | 16.91 | $ 8.55 |
Weighted-Average Exercise Price Per Share, Options exercisable | 11.16 | |
Weighted-Average Exercise Price Per Share, Options vested and expected to vest | $ 16.91 | |
Weighted-Average Remaining Contractual Term (years), Outstanding | 8 years 9 months 7 days | 9 years 4 months 24 days |
Weighted-Average Remaining Contractual Term (years), Options exercisable | 8 years 6 months | |
Weighted-Average Remaining Contractual Term (years), Options vested and expected to vest | 8 years 9 months 7 days | |
Aggregate Intrinsic Value, Outstanding, Beginning balance | $ 6,928 | |
Aggregate Intrinsic Value, Outstanding, Ending balance | 54,071 | $ 6,928 |
Aggregate Intrinsic Value, Options exercisable | 11,155 | |
Aggregate Intrinsic Value, Options vested and expected to vest | $ 54,071 |
Stockholders' Equity and Stoc_7
Stockholders' Equity and Stock-Based Compensation - Summary of Fair Value of Employee and Non-employee Stock Options Granted (Details) - $ / shares | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Non Employees | |||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
Expected term in years | 6 years 1 month 2 days | 9 years 2 months 12 days | 9 years 7 months 28 days |
Expected volatility | 73.67% | 73.87% | 80.08% |
Risk-free interest rate | 2.49% | 2.66% | 2.41% |
Dividend yield | 0.00% | 0.00% | 0.00% |
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 | 5 years 9 months 29 days |
Expected volatility | 72.39% | 71.99% | 68.40% |
Risk-free interest rate | 1.95% | 2.87% | 2.27% |
Dividend yield | 0.00% | 0.00% | 0.00% |
Weighted average fair value of share-based awards granted | $ 22.86 | $ 8.46 | $ 4.79 |
Stockholders' Equity and Stoc_8
Stockholders' Equity and Stock-Based Compensation - Schedule of Total Stock-based Compensation Expense Related to Stock-based Awards (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |||
Total stock-based compensation expense | $ 5,373 | $ 2,526 | $ 1,148 |
Options Available for Future Grants | |||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |||
Total stock-based compensation expense | 5,198 | 2,404 | 1,148 |
Employee Stock Plan | |||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |||
Total stock-based compensation expense | 175 | 122 | |
Research and Development | |||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |||
Total stock-based compensation expense | 2,313 | 1,325 | 519 |
General and Administrative | |||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |||
Total stock-based compensation expense | $ 3,060 | $ 1,201 | $ 629 |
Income taxes - Additional Infor
Income taxes - Additional Information (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Income Taxes [Line Items] | |||
Provision for income taxes | $ 0 | $ 0 | $ 0 |
Net operating loss carryforwards | 0 | 0 | $ 0 |
Increase (Decrease) in valuation allowance of deferred tax assets | 16,200,000 | $ 10,400,000 | |
Federal | |||
Income Taxes [Line Items] | |||
Net operating loss carryforwards | $ 84,400,000 | ||
Operating loss carryforwards begin to expire year | 2037 | ||
Federal | Research and Development | |||
Income Taxes [Line Items] | |||
Tax credit carryforwards | $ 1,500,000 | ||
Tax credit carryforward begin to expire year | 2037 | ||
Federal | Orphan Drug Credits [Member] | |||
Income Taxes [Line Items] | |||
Tax credit carryforwards | $ 8,900,000 | ||
State | California | |||
Income Taxes [Line Items] | |||
Net operating loss carryforwards | $ 45,800,000 | ||
Operating loss carryforwards begin to expire year | 2037 | ||
State | California | Research and Development | |||
Income Taxes [Line Items] | |||
Tax credit carryforwards | $ 1,000,000 |
Income taxes - Summary of Effec
Income taxes - Summary of Effective Tax Rate Differs from Federal Statutory Rate (Details) | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Income Tax Disclosure [Abstract] | |||
Federal statutory income tax rate | 21.00% | 21.00% | 34.00% |
State income taxes | 0.00% | 0.00% | 0.00% |
Federal rate change impact due to Tax Act | 0.00% | 0.00% | (13.40%) |
Research and development credits | 15.50% | 3.20% | 1.50% |
Stock-based compensation | 2.50% | (1.50%) | (1.50%) |
Change in fair value of convertible note | 0.00% | (1.60%) | 0.20% |
Other | 2.60% | (1.30%) | (0.70%) |
Change in valuation allowance | (41.60%) | (19.80%) | (20.10%) |
Effective income tax rate reconciliation | 0.00% | 0.00% | 0.00% |
Income taxes - Schedule of Defe
Income taxes - Schedule of Deferred Tax Assets (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Deferred tax assets: | ||
Net operating loss carryforward | $ 20,925 | $ 13,046 |
Research and development credits | 9,415 | 1,680 |
Stock-based compensation | 328 | |
Lease liability | 1,080 | |
Other | 23 | 37 |
Deferred tax assets before valuation allowance | 31,771 | 14,763 |
Less: valuation allowance | (30,727) | (14,566) |
Net deferred income tax assets | 1,044 | 197 |
Deferred tax liabilities: | ||
Stock-based compensation | $ (197) | |
Right of use assets | (842) | |
Fixed assets | $ (202) |
Income taxes - Reconciliation o
Income taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Income Tax Disclosure [Abstract] | |||
Balance at beginning of year | $ 525 | $ 166 | $ 31 |
Additions based on tax positions related to current year | 1,217 | 359 | 135 |
Balance at end of year | $ 1,742 | $ 525 | $ 166 |
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 | 12 Months Ended | |||||||||
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Numerator: | |||||||||||
Net loss attributable to common stockholders | $ (18,980) | $ 6,931 | $ (14,053) | $ (11,733) | $ (9,854) | $ (10,614) | $ (11,381) | $ (7,963) | $ (37,835) | $ (39,812) | $ (11,941) |
Denominator: | |||||||||||
Weighted average common shares outstanding | 37,114,930 | 22,037,363 | 4,324,525 | ||||||||
Weighted average unvested common shares subject to repurchase | (490,238) | (670,368) | (727,852) | ||||||||
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted | 36,624,692 | 21,366,995 | 3,596,673 | ||||||||
Net loss per share attributable to common stockholders, basic and diluted | $ (0.27) | $ (0.30) | $ (1.40) | $ (1.81) | $ (1.03) | $ (1.86) | $ (3.32) |
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 | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | |||
Antidilutive securities excluded from calculation of net loss per share | 1,690,720 | 1,962,407 | 17,051,170 |
Redeemable Convertible Preferred Stock | |||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | |||
Antidilutive securities excluded from calculation of net loss per share | 15,376,164 | ||
ESPP shares | |||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | |||
Antidilutive securities excluded from calculation of net loss per share | 1,318 | 5,115 | |
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 | 1,335,755 | 1,329,762 | 846,163 |
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 | 353,647 | 627,530 | 828,843 |
License Agreements - Additional
License Agreements - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended | ||||
Sep. 30, 2019 | Mar. 31, 2018 | Apr. 30, 2016 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Upfront payment received | $ 26,700,000 | |||||
License revenues | $ 26,691,000 | |||||
Research and development expense | 46,891,000 | $ 28,539,000 | $ 9,286,000 | |||
License and Service | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
License revenues | 26,700,000 | |||||
Common Stock | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Number of shares issued | 7,187,500 | |||||
Alexion | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Aggregate purchase price of shares issued | $ 23,309,000 | |||||
Alexion | Common Stock | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Number of shares issued | 556,173 | |||||
License Agreement | Alexion | Japan | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Upfront nonrefundable payment received | 25,000,000 | |||||
License Agreement | Alexion | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Upfront payment received | 25,000,000 | |||||
License Agreement | Alexion | Cost of License Revenue | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Research and development expense | $ 2,500,000 | |||||
License Agreement | Alexion | Japan | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Eligible amount receivable in regulatory milestone payment | 30,000,000 | |||||
License Agreement | Alexion | Japan | Maximum | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Eligible amount receivable in regulatory milestone payment | 30,000,000 | |||||
License Agreement | Stanford University | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
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 | |||||
License fees recognized upon achievement of development milestone | $ 50,000 | |||||
Research and development expense | $ 200,000 | $ 100,000 | 10,000 | |||
Percentage of non royalty amount payable | 10.00% | |||||
License Agreement | Stanford University | General and Administrative | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Upfront license payment amount | $ 25,000 | |||||
License Agreement | Stanford University | Research and Development | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
License fee paid | $ 10,000 | |||||
License Agreement | Stanford University | Common Stock | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Shares issued | 56,809 | |||||
Stock Purchase Agreement | Alexion | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Aggregate purchase price of shares issued | $ 25,000,000 | |||||
Closing price | $ 41.91 | |||||
Upfront payment received | $ 1,700,000 | |||||
License revenue premium | $ 1,700,000 | |||||
Stock Purchase Agreement | Alexion | Common Stock | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Number of shares issued | 556,173 | |||||
Shares issued price per share | $ 44.95 |
Commitments and Contingencies -
Commitments and Contingencies - Additional Information (Details) | Mar. 27, 2019USD ($)ft² | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) | Dec. 31, 2017USD ($) | Jan. 01, 2019USD ($) | Sep. 30, 2017 |
Commitments And Contingencies [Line Items] | ||||||
Lease payments | $ 6,296,000 | |||||
Lease liability | $ 1,200,000 | |||||
Operating Lease, right of use asset | $ 1,000,000 | 4,010,000 | $ 1,100,000 | |||
Tenant improvements recognized as expense | 56,000 | |||||
Gain on extinguishment of leasehold liability | 69,000 | |||||
Lease liabilities | $ 1,000,000 | 5,145,000 | ||||
Rent expense | $ 600,000 | $ 400,000 | $ 100,000 | |||
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 | |||||
Non-current Assets | San Francisco, California | ||||||
Commitments And Contingencies [Line Items] | ||||||
Security deposit for lease | $ 200,000 |
Commitments and Contingencies_2
Commitments and Contingencies - Schedule of Other Information of Operating Lease (Details) $ in Thousands | 12 Months Ended | |
Dec. 31, 2019USD ($) | ||
Commitments And Contingencies Disclosure [Abstract] | ||
Cash payments over lease term (in thousands) | $ 6,296 | |
Weighted average remaining lease term (months) | 82 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 | Dec. 31, 2019USD ($) |
Commitments And Contingencies Disclosure [Abstract] | |
2020 | $ 844 |
2021 | 869 |
2022 | 896 |
2023 | 922 |
2024 | 950 |
Thereafter | 1,815 |
Total | $ 6,296 |
Subsequent Events - Additional
Subsequent Events - Additional Information (Details) - Open Market Sale Agreement - USD ($) $ in Millions | Jan. 01, 2020 | Dec. 31, 2019 |
Subsequent Event [Line Items] | ||
Issue of shares of common stock | 385,613 | |
Proceeds from the issuance of common stock | $ 23.9 | |
Subsequent Event | ||
Subsequent Event [Line Items] | ||
Issue of shares of common stock | 448,755 | |
Proceeds from the issuance of common stock | $ 23.8 |
Supplementary Financial Data _3
Supplementary Financial Data (Unaudited) - Schedule of Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Quarterly Financial Information Disclosure [Abstract] | |||||||||||
Income (loss) from operations | $ (19,324) | $ 6,251 | $ (14,794) | $ (12,584) | $ (10,705) | $ (10,988) | $ (8,089) | $ (7,997) | $ (40,451) | $ (37,779) | $ (12,016) |
Net income (loss) attributable to common stockholders | $ (18,980) | $ 6,931 | $ (14,053) | $ (11,733) | $ (9,854) | $ (10,614) | $ (11,381) | $ (7,963) | $ (37,835) | $ (39,812) | $ (11,941) |
Net income (loss) per share of common stock attributable to common stockholders, basic | $ (0.51) | $ 0.19 | $ (0.39) | $ (0.32) | |||||||
Net income (loss) per share of common stock attributable to common stockholders, diluted | $ (0.51) | $ 0.18 | $ (0.39) | $ (0.32) | |||||||
Net loss per share attributable to common stockholders | $ (0.27) | $ (0.30) | $ (1.40) | $ (1.81) | $ (1.03) | $ (1.86) | $ (3.32) |