Document and Entity Information
Document and Entity Information - shares | 3 Months Ended | |
Mar. 31, 2019 | May 02, 2019 | |
Document And Entity Information [Abstract] | ||
Document Type | 10-Q | |
Amendment Flag | false | |
Document Period End Date | Mar. 31, 2019 | |
Document Fiscal Year Focus | 2019 | |
Document Fiscal Period Focus | Q1 | |
Trading Symbol | KZR | |
Entity Registrant Name | Kezar Life Sciences, Inc. | |
Entity Central Index Key | 0001645666 | |
Current Fiscal Year End Date | --12-31 | |
Entity Filer Category | Non-accelerated Filer | |
Entity Emerging Growth Company | true | |
Entity Small Business | true | |
Entity Ex Transition Period | true | |
Entity Common Stock, Shares Outstanding | 19,119,421 |
Condensed Consolidated Balance
Condensed Consolidated Balance Sheets - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018 |
Current assets: | ||
Cash and cash equivalents | $ 18,470 | $ 24,182 |
Marketable securities | 82,664 | 83,250 |
Prepaid expenses | 1,664 | 1,884 |
Other current assets | 991 | 489 |
Total current assets | 103,789 | 109,805 |
Property and equipment, net | 4,846 | 4,595 |
Other assets | 282 | 282 |
Total assets | 113,056 | 114,682 |
Operating lease right-of-use asset | 4,139 | |
Current liabilities: | ||
Accounts payable | 1,448 | 193 |
Accrued liabilities | 2,406 | 2,678 |
Operating lease liabilities, current | 804 | |
Deferred rent, current | 354 | |
Other liabilities, current | 100 | 112 |
Total current liabilities | 4,758 | 3,337 |
Operating lease liabilities, noncurrent | 6,153 | |
Deferred rent | 2,548 | |
Total liabilities | 10,911 | 5,885 |
Common stock, $0.001 par value, 125,000,000 shares authorized as of March 31, 2019 and December 31, 2018; 19,118,421 and 19,114,421 shares issued and outstanding as of March 31, 2019 and December 31, 2018, respectively | 19 | 19 |
Preferred stock, $0.001 par value, 10,000,000 shares authorized as of March 31, 2019 and December 31, 2018; zero shares issued and outstanding as of March 31, 2019 and December 31, 2018 | ||
Additional paid-in capital | 159,093 | 158,176 |
Accumulated other comprehensive loss | (130) | (203) |
Accumulated deficit | (56,837) | (49,195) |
Total stockholders' equity | 102,145 | 108,797 |
Total liabilities and stockholders' equity | $ 113,056 | $ 114,682 |
Condensed Consolidated Balanc_2
Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares | Mar. 31, 2019 | Dec. 31, 2018 |
Statement Of Financial Position [Abstract] | ||
Common stock, par value | $ 0.001 | $ 0.001 |
Common stock, shares authorized | 125,000,000 | 125,000,000 |
Common stock, shares issued | 19,118,421 | 19,114,421 |
Common stock, shares outstanding | 19,118,421 | 19,114,421 |
Preferred stock, par value | $ 0.001 | $ 0.001 |
Preferred stock, shares authorized | 10,000,000 | 10,000,000 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Condensed Consolidated Statemen
Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Operating expenses: | ||
Research and development | $ 5,927 | $ 3,572 |
General and administrative | 2,382 | 1,514 |
Total operating expenses | 8,309 | 5,086 |
Loss from operations | (8,309) | (5,086) |
Interest income | 667 | 139 |
Net loss | $ (7,642) | $ (4,947) |
Net loss per common share, basic and diluted | $ (0.40) | $ (6.53) |
Weighted-average shares used to compute net loss per common share, basic and diluted | 19,042,524 | 757,399 |
Condensed Consolidated Statem_2
Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Statement Of Income And Comprehensive Income [Abstract] | ||
Net loss | $ (7,642) | $ (4,947) |
Other comprehensive income (loss), net of tax: | ||
Foreign currency translation adjustments | 8 | (23) |
Unrealized gain on marketable securities | 65 | |
Total other comprehensive income (loss), net of tax | 73 | (23) |
Comprehensive loss | $ (7,569) | $ (4,970) |
Condensed Consolidated Statem_3
Condensed Consolidated Statement of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands | Total | Redeemable Convertible Preferred stock | Common Stock | Additional Paid-in Capital | Accumulated Other Comprehensive Income (Loss) | Accumulated Deficit |
Balance at Dec. 31, 2017 | $ (25,687) | $ 1 | $ 451 | $ (111) | $ (26,028) | |
Balance, shares at Dec. 31, 2017 | 948,578 | |||||
Balance at Dec. 31, 2017 | $ 77,931 | |||||
Balance, shares at Dec. 31, 2017 | 12,263,126 | |||||
Issuance of common stock upon exercise of stock options, net of amount related to early exercised options | 25 | 25 | ||||
Issuance of common stock upon exercise of stock options, net of amount related to early exercised options, shares | 109,818 | |||||
Vesting related to common shares issued pursuant to early exercises | 17 | 17 | ||||
Stock-based compensation expense | 126 | 126 | ||||
Other comprehensive loss | (23) | (23) | ||||
Net loss | (4,947) | (4,947) | ||||
Balance at Mar. 31, 2018 | (30,489) | $ 1 | 619 | (134) | (30,975) | |
Balance, shares at Mar. 31, 2018 | 1,058,396 | |||||
Balance at Mar. 31, 2018 | $ 77,931 | |||||
Balance, shares at Mar. 31, 2018 | 12,263,126 | |||||
Balance at Dec. 31, 2018 | 108,797 | $ 19 | 158,176 | (203) | (49,195) | |
Balance, shares at Dec. 31, 2018 | 19,114,421 | |||||
Balance at Dec. 31, 2018 | $ 0 | |||||
Balance, shares at Dec. 31, 2018 | 0 | |||||
Issuance of common stock upon exercise of stock options, net of amount related to early exercised options | $ 4 | 4 | ||||
Issuance of common stock upon exercise of stock options, net of amount related to early exercised options, shares | 4,000 | 4,000 | ||||
Vesting related to common shares issued pursuant to early exercises | $ 12 | 12 | ||||
Stock-based compensation expense | 901 | 901 | ||||
Other comprehensive loss | 73 | 73 | ||||
Net loss | (7,642) | (7,642) | ||||
Balance at Mar. 31, 2019 | $ 102,145 | $ 19 | $ 159,093 | $ (130) | $ (56,837) | |
Balance, shares at Mar. 31, 2019 | 19,118,421 | |||||
Balance at Mar. 31, 2019 | $ 0 | |||||
Balance, shares at Mar. 31, 2019 | 0 |
Condensed Consolidated Statem_4
Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Cash flows from operating activities: | ||
Net loss | $ (7,642) | $ (4,947) |
Adjustments to reconcile net loss to net cash used in operating activities: | ||
Depreciation and amortization | 303 | 87 |
Stock-based compensation | 901 | 126 |
Amortization of premiums and discounts on marketable securities | (359) | |
Loss on disposal of property and equipment | 97 | |
Changes in operating assets and liabilities | ||
Prepaid expenses and other current assets | (282) | (641) |
Other assets | 39 | |
Accounts payable and accrued liabilities | 560 | 1,028 |
Other liabilities, current | 149 | |
Deferred rent | 296 | |
Operating lease liabilities | (181) | |
Net cash used in operating activities | (6,700) | (3,766) |
Cash flows from investing activities: | ||
Purchases of property and equipment | (34) | (195) |
Purchases of marketable securities | (35,936) | |
Maturities of marketable securities | 36,946 | |
Net cash provided by (used in) investing activities | 976 | (195) |
Cash flows from financing activities: | ||
Proceeds from the exercise of stock options | 4 | 25 |
Net cash provided by financing activities | 4 | 25 |
Effect of exchange rate changes on cash and cash equivalents and restricted cash | 8 | (12) |
Net decrease in cash, cash equivalents and restricted cash | (5,712) | (3,948) |
Cash, cash equivalents and restricted cash at the beginning of period | 24,182 | 51,046 |
Cash, cash equivalents and restricted cash at the end of period | 18,470 | 47,098 |
Supplemental disclosures of noncash investing and financing information: | ||
Reclassification of employee stock liability to equity upon vesting | 12 | 17 |
Addition of tenant improvement paid by landlord | 2,054 | |
Purchase of property and equipment in accounts payable | $ 423 | 21 |
Deferred offering costs in accrued liabilities | $ 1,300 |
Organization and Description of
Organization and Description of the Business | 3 Months Ended |
Mar. 31, 2019 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Organization and Description of the Business | 1. Organization and Description of the Business Description of Business Kezar Life Sciences, Inc. (the “Company,” Liquidity Since commencing operations in mid-2015, substantially all of the Company’s efforts have been focused on research, development, and the advancement of the Company’s lead product candidate, KZR-616. The Company’s ultimate success depends on the outcome of the ongoing research and development activities. The Company has not yet generated product sales and as a result has experienced operating losses since inception and had an accumulated deficit of $56.8 million as of March 31, 2019. The Company expects to incur additional losses in the future to conduct research and development and will need to raise additional capital to fully implement management’s business plan. The Company intends to raise such capital through the issuance of additional equity, and potentially through borrowings, strategic alliances with partner companies and other licensing transactions. However, if such financing is not available at adequate levels, the Company may need to reevaluate its operating plans. Management believes that its existing cash, cash equivalents and marketable securities will be sufficient to fund the Company’s cash requirements for at least 12 months following the issuance of these financial statements. |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 3 Months Ended |
Mar. 31, 2019 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies Significant Accounting Policies The Company’s significant accounting policies are disclosed in the audited consolidated financial statements for the year ended December 31, 2018 and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2018, filed with the U.S. Securities and Exchange Commission (“SEC”) on March 26, 2019 and except for the adoption of the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842), there ha ve been no material changes during the three months ended March 31, 2019. Basis of Presentation and Consolidation The condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and include the Company’s accounts and those of its wholly owned Australian subsidiary, Unaudited Interim Condensed Consolidated Financial Statements The accompanying financial information as of March 31, 2019 is unaudited. The condensed consolidated financial statements included in this report reflect all adjustments (consisting only of normal recurring adjustments) that our management considers necessary for the fair statement of the results of operations for the interim periods covered and of our financial condition at the date of the interim balance sheet. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. The results for interim periods are not necessarily indicative of the results for the entire year or any other interim period. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2018, filed with the SEC on March 26, 2019. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant items subject to such estimates and assumptions include the useful lives of fixed assets, stock-based compensation, and accrued research and development costs. Management bases its estimates on historical experience and on various other market-specific relevant assumptions that management believes to be reasonable under the circumstances. Actual results may differ from those estimates. Cash and Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents. Cash equivalents consist of corporate debt securities and highly liquid money market funds. Restricted cash at January 1, 2018 consisted of approximately a $13,000 deposit at the bank held as collateral for the Company’s credit card program. The collateral requirement was removed and released in May 2018. Marketable Securities All marketable securities have been classified as “available-for-sale” in accordance with the Company’s investment policy and cash management strategy. Short-term marketable securities mature within one-year from the balance sheet date. Investments in marketable securities are recorded at fair value, with any unrealized gains and losses reported within accumulated other comprehensive income as a separate component of stockholders’ deficit until realized or until a determination is made that an other-than-temporary decline in market value has occurred. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion, together with interest on securities, are included in interest income on the Company’s condensed consolidated statements of operations. Leases Accounting Pronouncements Adopted in 2019 Leases (Topic 842) In February 2016, the Leases (Topic 842) Leases (Topic 842): Targeted Improvements The Company adopted the new standard on January 1, 2019 and used the effective date as its date of initial application. Consequently, financial information will not be restated and the disclosures required under the new standard will not be provided for dates and periods before January 1, 2019. The Company elected the package of transition practical expedients that allows the Company not to reassess the lease classification for any expired or existing contracts, whether initial direct costs were incurred, or whether any expired or existing contracts contained leases. This standard had a material effect on the Company’s financial statements. The most significant effects relate to (1) the recognition of new ROU asset and lease liabilities on the balance sheet for the operating lease for its headquarters at 4000 Shoreline Court, South San Francisco; and (2) providing significant new disclosures about its leasing activities. The following table discloses the impact on our balance sheet upon adoption (in thousands): January 1, 2019 December 31, 2018 Operating lease ROU asset $ 4,236 $ — Operating lease liabilities, current 774 — Operating lease liabilities, noncurrent 6,364 — Deferred rent, current — 354 Deferred rent, noncurrent — 2,548 The new standard also provides practical expedients for an entity’s ongoing accounting. The Company elected the short-term lease recognition exemption for all leases that qualify. This means, for those leases that qualify, the Company will not recognize ROU assets or lease liabilities, and this includes not recognizing ROU assets or lease liabilities for existing short-term leases of those assets in transition. The Company did not elect the practical expedient to not separate lease and non-lease components for all of its leases. Stock Compensation (Topic 718) In June 2018, the FASB issued ASU No. 2018-07, Compensation – Stock Compensation (Topic 718) The Company adopted the new standard on January 1, 2019 and determined that New Accounting Pronouncements Not Yet Adopted , Financial Instruments-Credit Losses (Topic 326) In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement The amendment of ASU No. 2018-13 removes disclosure requirements from Topic 820 in the areas of (1) the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy; (2) the policy for timing of transfers between levels, and (3) the valuation processes for Level 3 fair value measurements. |
Fair Value Measurements
Fair Value Measurements | 3 Months Ended |
Mar. 31, 2019 | |
Fair Value Disclosures [Abstract] | |
Fair Value Measurements | 3. Fair Value Measurements Financial assets and liabilities are recorded at fair value. The carrying amount of certain financial instruments, including cash and cash equivalents, restricted cash, accounts payable and accrued liabilities, approximate fair value due to their relatively short maturities. Assets and liabilities recorded at fair value on a recurring basis in the condensed consolidated balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements 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. 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. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. We determine the fair value of Level 1 assets using quoted prices in active markets for identical assets. We review trading activity and pricing for Level 2 investments as of each measurement date. Level 2 inputs, which are obtained from various third-party data providers, represent quoted prices for similar assets in active markets and were derived from observable market data, or, if not directly observable, were derived from or corroborated by other observable market data. There were no transfers between Level 1 and Level 2 securities in the periods presented. In certain cases, where there is limited activity or less transparency around inputs to valuation, securities are classified as Level 3 within the valuation hierarchy. The Company does not have any assets or liabilities measured using Level 3 inputs as of March 31, 2019 or December 31, 2018. The following table summarizes our financial assets measured at fair value on a recurring basis and classified under the appropriate level of the fair value hierarchy as described above (in thousands): March 31, 2019 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 18,349 $ 18,349 $ — $ — U.S. Treasury securities 13,695 13,695 — — Commercial paper 19,357 — 19,357 — Corporate debt securities 20,538 — 20,538 — Government agency bonds 29,075 — 29,075 — Total $ 101,014 $ 32,044 $ 68,970 $ — December 31, 2018 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 23,156 $ 23,156 $ — $ — U.S. Treasury securities 25,692 25,692 — — Commercial paper 19,190 — 19,190 — Corporate debt securities 20,451 — 20,451 — Government agency bonds 17,917 — 17,917 — Total $ 106,406 $ 48,848 $ 57,558 $ — |
Available-for-Sale Securities
Available-for-Sale Securities | 3 Months Ended |
Mar. 31, 2019 | |
Investments Debt And Equity Securities [Abstract] | |
Available-for-Sale Securities | 4. Available-for-Sale Securities The following table is a summary of available-for-sale securities recorded in cash and cash equivalents or marketable securities in our condensed consolidated balance sheets (in thousands): March 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Financial Assets Money market funds 18,349 — — 18,349 U.S. Treasury securities 13,691 4 — 13,695 Commercial paper 19,342 15 — 19,357 Corporate debt securities 20,521 17 — 20,538 Government agency bonds 29,066 9 — 29,075 Total $ 100,969 $ 45 $ — $ 101,014 December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Financial Assets Money market funds $ 23,156 $ — $ — $ 23,156 U.S. Treasury securities 25,698 — (6 ) 25,692 Commercial paper 19,203 — (13 ) 19,190 Corporate debt securities 20,449 4 (2 ) 20,451 Government agency bonds 17,921 — (4 ) 17,917 Total $ 106,427 $ 4 $ (25 ) $ 106,406 As of March 31, 2019, the amortized cost and estimated fair value of the Company’s available-for-sale securities by contractual maturity are shown below (in thousands): Amortized Estimated Cost Fair Value Marketable securities maturing: In one year or less $ 82,619 $ 82,664 Total marketable securities $ 82,619 $ 82,664 |
Balance Sheet Components
Balance Sheet Components | 3 Months Ended |
Mar. 31, 2019 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Balance Sheet Components | 5. Balance Sheet Components Property and Equipment, Net Property and equipment consists of the following (in thousands): March 31, 2019 December 31, 2018 Leasehold improvements $ 3,268 $ 3,268 Furniture, laboratory and office equipment 2,489 2,043 Computer equipment 230 219 Total property and equipment 5,987 5,530 Less accumulated depreciation and amortization (1,141 ) (935 ) Property and equipment, net $ 4,846 $ 4,595 Depreciation expense was $0.2 million and $0.1 million for the three months ended March 31, 2019 and 2018, respectively. Accrued Liabilities Accrued liabilities consisted of the following (in thousands): March 31, 2019 December 31, 2018 Accrued preclinical and research costs $ 1,128 $ 1,146 Accrued clinical costs 528 434 Accrued employee-related costs 554 736 Accrued professional services 90 138 Other 106 224 Total accrued liabilities $ 2,406 $ 2,678 |
Operating Lease
Operating Lease | 3 Months Ended |
Mar. 31, 2019 | |
Leases [Abstract] | |
Operating Lease | 6. Operating Lease In August 2017, the Company entered into a lease agreement to lease 24,357 square feet of combination laboratory and office space in South San Francisco, California. This lease expires in February 2025. The contractually specified minimum rent and annual rent increases for the operating lease are included in the measurement of the ROU asset and related lease liabilities. Under the lease arrangement, we may be required to pay directly, or reimburse the lessor for real estate taxes, insurance, utilities, maintenance and other operating costs. Such amounts are generally variable and therefore not included in the measurement of the ROU asset and related lease liability but are instead recognized as variable lease expense in our Condensed Consolidated Statements of Operations when they are incurred. The option to extend the lease was not recognized as part of the Company’s lease liability and ROU asset. Because the rate implicit in the lease is not readily determinable, the Company uses its incremental borrowing rate to determine the present value of the lease payments. The Company recorded lease liabilities and ROU asset for its office lease based on the present value of lease payments over the expected lease term. Information related to the Company’s ROU asset and related lease liabilities were as follows (in thousands): For three months ended March 31, 2019 Cash paid for operating lease liabilities $ 181 Remaining lease term 5.92 years Discount rate 10 % Maturities of lease liabilities as of March 31, 2019 were as follows: 2019 $ 1,095 2020 1,497 2021 1,542 2022 1,588 2023 1,635 2024 1,684 Thereafter 282 Total undiscounted lease payments 9,323 Less: imputed interest (2,366 ) Total lease liabilities $ 6,957 Operating lease liabilities, current 804 Operating lease liabilities, noncurrent 6,153 Total operating lease liabilities $ 6,957 Future minimum lease payments are as follows as of December 31, 2018 (in thousands): Year ending December 31: 2019 $ 1,453 2020 1,497 2021 1,542 2022 1,588 2023 1,635 Thereafter 1,966 Total future minimum lease payments $ 9,681 |
Stock-Based Compensation
Stock-Based Compensation | 3 Months Ended |
Mar. 31, 2019 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Stock-Based Compensation | 7. Stock-Based Compensation Stock Incentive Plans 2018 Equity Incentive Plan In June 2018, the Company’s board of directors adopted and its stockholders approved the 2018 Equity Incentive Plan (the “2018 Plan”), which became effective as of June 20, 2018, at which point no further grants will be made under the 2015 Equity Incentive Plan (the “2015 Plan”) described below. Under the 2018 Plan, the Company may grant incentive stock options (“ISOs”), nonstatutory stock options (“NSOs”), stock appreciation rights, restricted stock awards, restricted stock units (“RSUs”) and other stock-based awards for the purchase of that number of shares of common stock. As of March 31, 2019, options to purchase 663,621 shares of common stock and 10,189 RSUs have been granted and 2,179,866 shares were available for future issuance under the 2018 Plan. Initially, subject to adjustment as provided in the 2018 Plan, the aggregate number of shares of the Company’s common stock that may be issued pursuant to stock awards under the 2018 Plan will not exceed 4,000,000 shares, which is the sum of (i) 1,600,692 shares plus (ii) the number of shares reserved, and remaining available for issuance, under the 2015 Plan at the time the 2018 Plan became effective and (iii) the number of shares subject to stock options or other stock awards granted under the 2015 Plan that expire, terminate are forfeited or otherwise not issued, or are withheld to satisfy a tax withholding obligation in connection with an award or to satisfy a purchase or exercise price of an award (such as upon the expiration or termination of a stock award prior to vesting). The number of shares of the Company’s common stock reserved for issuance under the 2018 Plan will automatically increase on January 1 of each year, beginning on January 1, 2019 and continuing through and including January 1, 2028, by 5% of the total number of shares of capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by the Company’s board of directors. The maximum number of shares that may be issued upon the exercise of ISOs under the 2018 Plan is 12,500,000 shares. 2015 Equity Incentive Plan The Company’s 2015 Equity Incentive Plan provided for the granting of ISOs and NSOs to employees, directors and consultants at the discretion of the board of directors. The 2015 Plan was terminated as to future awards in June 2018, although it continues to govern the terms of options that remain outstanding under the 2015 Plan. No additional stock awards will be granted under the 2015 Plan, and all outstanding stock awards granted under the 2015 Plan that are repurchased, forfeited, expire or are cancelled will become available for grant under the 2018 Plan in accordance with its terms. Options granted under the 2015 Plan expire no later than 10 years from the date of grant. Options granted under the 2015 Plan vest over periods determined by the board of directors, generally over four years. The 2015 Plan allows for early exercise of certain options prior to vesting. Upon termination of employment, the unvested shares are subject to repurchase at the original exercise price. As of March 31, 2019, options to purchase 2,091,845 shares of common stock were outstanding under the 2015 Plan. 2018 Employee Stock Purchase Plan In June 2018, the Company’s board of directors and its stockholders approved the 2018 Employee Stock Purchase Plan (the “ESPP”), which became effective as of June 20, 2018. The ESPP is intended to qualify as an “employee stock purchase plan” within the meaning of Section 423 of the U.S. Internal Revenue Code of 1986, as amended. The number of shares of common stock initially reserved for issuance under the ESPP was 200,000 shares. The ESPP provides for an annual increase on the first day of each year beginning in 2019 and ending in 2028, in each case subject to the approval of the board of directors, equal to the lesser of (i) 1% of the shares of common stock outstanding on the last day of the prior fiscal year or (ii) 375,000 shares; provided, that prior to the date of any such increase, the board of directors may determine that such increase will be less than the amount set forth in clauses (i) and (ii). As of March 31, 2019, no shares of common stock had been issued under the ESPP and 391,144 shares remained available for future issuance under the ESPP. The option price per share of common stock to be paid by a participant upon exercise of the participant’s option on the applicable exercise date for an offering period shall be equal to 85% of the lesser of the fair market value of a share of common stock on (a) the applicable grant date or (b) the applicable exercise date. The Board authorized an initial offering beginning on November 16, 2018 and ending on May 15, 2019. Following the end of the initial offering, a new offering will automatically begin on the day that immediately follows the conclusion of the preceding offering. Stock Option Activity The following table summarizes activity under the Company’s stock option plan and related information (in thousands, except share and per share amounts): Number of Options Outstanding Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value Outstanding at December 31, 2018 2,181,466 $ 3.80 8.5 $ 43,189 Options granted 578,000 $ 22.50 Options exercised (4,000 ) $ 0.90 $ 78 Options cancelled — $ — Outstanding at March 31, 2019 2,755,466 $ 7.73 8.6 $ 30,395 Vested and exercisable at March 31, 2019 1,104,476 $ 2.93 7.8 $ 16,468 The weighted average grant date fair value of options granted during the three months ended March 31, 2019 was $15.79 per share. The 2015 Plan allows for early exercisable option grants, which permit the grantee to exercise a stock option in exchange for stock before the requisite service is provided (e.g., before the award is vested under its original terms); however, such arrangements permit the Company to subsequently repurchase such shares at the exercise price if the vesting conditions are not satisfied. To date, the Company has made such grants only to non-employee board members. The total intrinsic value of exercised stock options during the three months ended March 31, 2019 was $78,000. The aggregate intrinsic value is calculated as the difference between the exercise price and the estimated fair value of the Company’s common stock at the date of exercise. Early Exercise Stock Purchase Agreements As of March 31, 2019 and December 31, 2018, there were 56,038 and 68,349, respectively, of nonvested common shares outstanding that were exercised early and subject to repurchase by the Company at the original issuance price upon termination of the stockholder’s services. The right to repurchase these shares generally lapses with respect to 25% of the shares underlying the option after the applicable vesting commencement date and 1/48 of the shares underlying the original grant per month for 36 months thereafter. The shares purchased pursuant to the early exercise of stock options are not deemed, for accounting purposes, to be issued until those shares vest. The cash received in exchange for exercised and nonvested shares related to stock options granted is recorded as a liability for the early exercise of stock options on the balance sheets with the corresponding par value in common stock and an offset in additional paid-in capital. Restricted Stock In addition to the nonvested common shares outstanding described above at “Early Exercise Stock Purchase Agreements,” the Company issued restricted stock to its founders. The fair value of restricted stock on the issuance date is deemed equal to the cash consideration paid by the founders. Restricted stock vests over a four-year period from the applicable vesting commencement date. The following summarizes the activity of nonvested restricted stock: Number of Shares Nonvested—December 31, 2018 20,908 Vested (15,681 ) Nonvested—March 31, 2019 5,227 Stock-Based Compensation Expense Total stock-based compensation recognized by function was as follows (in thousands): Three Months Ended March 31, 2019 2018 Research and development $ 447 $ 59 General and administrative 454 67 Total stock-based compensation expense $ 901 $ 126 As of March 31, 2019, the unrecognized stock-based compensation cost and the estimated weighted average amortization period, using the straight-line attribution method, was as follows (dollars in thousands): Unrecognized Compensation Cost Weighted Average Remaining Amortization Period (Years) Employee options $ 12,243 2.9 Nonemployee options 2 0.2 Total unrecognized stock-based compensation expense $ 12,245 The fair value of the employee stock options granted is calculated using the Black-Scholes option-pricing model with the following weighted-average assumptions: Three Months Ended March 31, 2019 2018 Expected term (years) 5.9 6.0 Expected volatility 79.9 - 81.9% 82.0 % Risk-free interest rate 2.4 - 2.6% 2.6 % Expected dividend yield — — |
Income Taxes
Income Taxes | 3 Months Ended |
Mar. 31, 2019 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | 8. Income Taxes No provision for income taxes was recorded for the three months ended March 31, 2019 and 2018, respectively. Deferred tax assets generated from the Company’s net operating losses have been fully reserved, as the Company believes it is not more likely than not that the benefit will be realized. In December 2015, the Protecting Americans from Tax Hikes (PATH) Act of 2015 was signed into law, which created several new research and development (“R&D”) tax credit provisions, including allowing qualified small businesses to utilize the R&D credit against the employer’s portion of payroll tax up to a maximum of $250,000 per year. The Company qualified as a small business under PATH for both 2016 and 2017. The Company has not yet filed its federal tax return for 2018 in which the Company will determine whether it qualifies as a small business under the PATH Act. During the three months ended March 31, 2019, the Company utilized $93,000 of R&D tax credits as a reduction of payroll expenses to offset its payroll tax liabilities. The remaining R&D tax credits available for future payroll tax liabilities have been recorded as deferred tax assets with a full valuation allowance. |
Net Loss per Share
Net Loss per Share | 3 Months Ended |
Mar. 31, 2019 | |
Earnings Per Share [Abstract] | |
Net Loss Per Share | 9. Net Loss Per Share Net Loss Per Share The following table sets forth the calculation of basic and diluted net loss per share during the periods presented (in thousands, except share and per share data): Three Months Ended March 31, 2019 2018 Numerator: Net loss $ (7,642 ) $ (4,947 ) Denominator: Weighted-average shares of common stock outstanding 19,042,524 757,399 Net loss per share, basic and diluted $ (0.40 ) $ (6.53 ) The following outstanding shares of common stock equivalents were excluded from the computation of the diluted net loss per share for the periods presented because their effect would have been anti-dilutive: Three Months Ended March 31, 2019 2018 Redeemable convertible preferred stock on an if converted basis — 12,263,126 Stock options to purchase common stock 2,755,466 1,354,965 Common stock subject to future vesting 61,265 252,303 Total 2,816,731 13,870,394 |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 3 Months Ended |
Mar. 31, 2019 | |
Accounting Policies [Abstract] | |
Basis of presentation and consolidation | Basis of Presentation and Consolidation The condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and include the Company’s accounts and those of its wholly owned Australian subsidiary, |
Unaudited Interim Condensed Consolidated Financial Statements | Unaudited Interim Condensed Consolidated Financial Statements The accompanying financial information as of March 31, 2019 is unaudited. The condensed consolidated financial statements included in this report reflect all adjustments (consisting only of normal recurring adjustments) that our management considers necessary for the fair statement of the results of operations for the interim periods covered and of our financial condition at the date of the interim balance sheet. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. The results for interim periods are not necessarily indicative of the results for the entire year or any other interim period. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2018, filed with the SEC on March 26, 2019. |
Use of Estimates | Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant items subject to such estimates and assumptions include the useful lives of fixed assets, stock-based compensation, and accrued research and development costs. Management bases its estimates on historical experience and on various other market-specific relevant assumptions that management believes to be reasonable under the circumstances. Actual results may differ from those estimates. |
Cash and Cash Equivalents and Restricted Cash | Cash and Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents. Cash equivalents consist of corporate debt securities and highly liquid money market funds. Restricted cash at January 1, 2018 consisted of approximately a $13,000 deposit at the bank held as collateral for the Company’s credit card program. The collateral requirement was removed and released in May 2018. |
Marketable Securities | Marketable Securities All marketable securities have been classified as “available-for-sale” in accordance with the Company’s investment policy and cash management strategy. Short-term marketable securities mature within one-year from the balance sheet date. Investments in marketable securities are recorded at fair value, with any unrealized gains and losses reported within accumulated other comprehensive income as a separate component of stockholders’ deficit until realized or until a determination is made that an other-than-temporary decline in market value has occurred. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion, together with interest on securities, are included in interest income on the Company’s condensed consolidated statements of operations. |
Leases | Leases |
Accounting Pronouncements Adopted in 2019 and New Accounting Pronouncements Not Yet Adopted | Accounting Pronouncements Adopted in 2019 Leases (Topic 842) In February 2016, the Leases (Topic 842) Leases (Topic 842): Targeted Improvements The Company adopted the new standard on January 1, 2019 and used the effective date as its date of initial application. Consequently, financial information will not be restated and the disclosures required under the new standard will not be provided for dates and periods before January 1, 2019. The Company elected the package of transition practical expedients that allows the Company not to reassess the lease classification for any expired or existing contracts, whether initial direct costs were incurred, or whether any expired or existing contracts contained leases. This standard had a material effect on the Company’s financial statements. The most significant effects relate to (1) the recognition of new ROU asset and lease liabilities on the balance sheet for the operating lease for its headquarters at 4000 Shoreline Court, South San Francisco; and (2) providing significant new disclosures about its leasing activities. The following table discloses the impact on our balance sheet upon adoption (in thousands): January 1, 2019 December 31, 2018 Operating lease ROU asset $ 4,236 $ — Operating lease liabilities, current 774 — Operating lease liabilities, noncurrent 6,364 — Deferred rent, current — 354 Deferred rent, noncurrent — 2,548 The new standard also provides practical expedients for an entity’s ongoing accounting. The Company elected the short-term lease recognition exemption for all leases that qualify. This means, for those leases that qualify, the Company will not recognize ROU assets or lease liabilities, and this includes not recognizing ROU assets or lease liabilities for existing short-term leases of those assets in transition. The Company did not elect the practical expedient to not separate lease and non-lease components for all of its leases. Stock Compensation (Topic 718) In June 2018, the FASB issued ASU No. 2018-07, Compensation – Stock Compensation (Topic 718) The Company adopted the new standard on January 1, 2019 and determined that New Accounting Pronouncements Not Yet Adopted , Financial Instruments-Credit Losses (Topic 326) In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement The amendment of ASU No. 2018-13 removes disclosure requirements from Topic 820 in the areas of (1) the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy; (2) the policy for timing of transfers between levels, and (3) the valuation processes for Level 3 fair value measurements. |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies (Tables) | 3 Months Ended |
Mar. 31, 2019 | |
Accounting Policies [Abstract] | |
Impact of Accounting Pronouncements Adoption on Balance Sheet | The following table discloses the impact on our balance sheet upon adoption (in thousands): January 1, 2019 December 31, 2018 Operating lease ROU asset $ 4,236 $ — Operating lease liabilities, current 774 — Operating lease liabilities, noncurrent 6,364 — Deferred rent, current — 354 Deferred rent, noncurrent — 2,548 |
Fair Value Measurements (Tables
Fair Value Measurements (Tables) | 3 Months Ended |
Mar. 31, 2019 | |
Fair Value Disclosures [Abstract] | |
Summary of Financial Assets Measured at Fair Value on a Recurring Basis | The following table summarizes our financial assets measured at fair value on a recurring basis and classified under the appropriate level of the fair value hierarchy as described above (in thousands): March 31, 2019 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 18,349 $ 18,349 $ — $ — U.S. Treasury securities 13,695 13,695 — — Commercial paper 19,357 — 19,357 — Corporate debt securities 20,538 — 20,538 — Government agency bonds 29,075 — 29,075 — Total $ 101,014 $ 32,044 $ 68,970 $ — December 31, 2018 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 23,156 $ 23,156 $ — $ — U.S. Treasury securities 25,692 25,692 — — Commercial paper 19,190 — 19,190 — Corporate debt securities 20,451 — 20,451 — Government agency bonds 17,917 — 17,917 — Total $ 106,406 $ 48,848 $ 57,558 $ — |
Available-for-Sale Securities (
Available-for-Sale Securities (Tables) | 3 Months Ended |
Mar. 31, 2019 | |
Investments Debt And Equity Securities [Abstract] | |
Summary of Available-For-Sale Securities Recorded in Cash and Cash Equivalents or Marketable Securities | The following table is a summary of available-for-sale securities recorded in cash and cash equivalents or marketable securities in our condensed consolidated balance sheets (in thousands): March 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Financial Assets Money market funds 18,349 — — 18,349 U.S. Treasury securities 13,691 4 — 13,695 Commercial paper 19,342 15 — 19,357 Corporate debt securities 20,521 17 — 20,538 Government agency bonds 29,066 9 — 29,075 Total $ 100,969 $ 45 $ — $ 101,014 December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Financial Assets Money market funds $ 23,156 $ — $ — $ 23,156 U.S. Treasury securities 25,698 — (6 ) 25,692 Commercial paper 19,203 — (13 ) 19,190 Corporate debt securities 20,449 4 (2 ) 20,451 Government agency bonds 17,921 — (4 ) 17,917 Total $ 106,427 $ 4 $ (25 ) $ 106,406 |
Summary of Amortized Cost and Estimated Fair Value of Available-for-sale Securities by Contractual Maturity | As of March 31, 2019, the amortized cost and estimated fair value of the Company’s available-for-sale securities by contractual maturity are shown below (in thousands): Amortized Estimated Cost Fair Value Marketable securities maturing: In one year or less $ 82,619 $ 82,664 Total marketable securities $ 82,619 $ 82,664 |
Balance Sheet Components (Table
Balance Sheet Components (Tables) | 3 Months Ended |
Mar. 31, 2019 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Property and Equipment | Property and equipment consists of the following (in thousands): March 31, 2019 December 31, 2018 Leasehold improvements $ 3,268 $ 3,268 Furniture, laboratory and office equipment 2,489 2,043 Computer equipment 230 219 Total property and equipment 5,987 5,530 Less accumulated depreciation and amortization (1,141 ) (935 ) Property and equipment, net $ 4,846 $ 4,595 |
Accrued Liabilities | Accrued liabilities consisted of the following (in thousands): March 31, 2019 December 31, 2018 Accrued preclinical and research costs $ 1,128 $ 1,146 Accrued clinical costs 528 434 Accrued employee-related costs 554 736 Accrued professional services 90 138 Other 106 224 Total accrued liabilities $ 2,406 $ 2,678 |
Operating Lease (Tables)
Operating Lease (Tables) | 3 Months Ended |
Mar. 31, 2019 | |
Leases [Abstract] | |
Details of Right-of-Use Assets and Lease Liabilities | Information related to the Company’s ROU asset and related lease liabilities were as follows (in thousands): For three months ended March 31, 2019 Cash paid for operating lease liabilities $ 181 Remaining lease term 5.92 years Discount rate 10 % Maturities of lease liabilities as of March 31, 2019 were as follows: 2019 $ 1,095 2020 1,497 2021 1,542 2022 1,588 2023 1,635 2024 1,684 Thereafter 282 Total undiscounted lease payments 9,323 Less: imputed interest (2,366 ) Total lease liabilities $ 6,957 Operating lease liabilities, current 804 Operating lease liabilities, noncurrent 6,153 Total operating lease liabilities $ 6,957 |
Schedule of Future Minimum Lease Payments | Future minimum lease payments are as follows as of December 31, 2018 (in thousands): Year ending December 31: 2019 $ 1,453 2020 1,497 2021 1,542 2022 1,588 2023 1,635 Thereafter 1,966 Total future minimum lease payments $ 9,681 |
Stock-Based Compensation (Table
Stock-Based Compensation (Tables) | 3 Months Ended |
Mar. 31, 2019 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Summary of Activity under Stock Option Plan and Related Information | The following table summarizes activity under the Company’s stock option plan and related information (in thousands, except share and per share amounts): Number of Options Outstanding Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value Outstanding at December 31, 2018 2,181,466 $ 3.80 8.5 $ 43,189 Options granted 578,000 $ 22.50 Options exercised (4,000 ) $ 0.90 $ 78 Options cancelled — $ — Outstanding at March 31, 2019 2,755,466 $ 7.73 8.6 $ 30,395 Vested and exercisable at March 31, 2019 1,104,476 $ 2.93 7.8 $ 16,468 |
Summarizes of Activity of Nonvested Restricted Stock | The following summarizes the activity of nonvested restricted stock: Number of Shares Nonvested—December 31, 2018 20,908 Vested (15,681 ) Nonvested—March 31, 2019 5,227 |
Stock-Based Compensation Recognized | Total stock-based compensation recognized by function was as follows (in thousands): Three Months Ended March 31, 2019 2018 Research and development $ 447 $ 59 General and administrative 454 67 Total stock-based compensation expense $ 901 $ 126 |
Unrecognized Stock-based Compensation Cost and Estimated Weighted Average Amortization Period | As of March 31, 2019, the unrecognized stock-based compensation cost and the estimated weighted average amortization period, using the straight-line attribution method, was as follows (dollars in thousands): Unrecognized Compensation Cost Weighted Average Remaining Amortization Period (Years) Employee options $ 12,243 2.9 Nonemployee options 2 0.2 Total unrecognized stock-based compensation expense $ 12,245 |
Fair Value of Employee Stock Options Granted is Calculated Using Black Scholes Option Pricing Model with Weighted Average Assumptions | The fair value of the employee stock options granted is calculated using the Black-Scholes option-pricing model with the following weighted-average assumptions: Three Months Ended March 31, 2019 2018 Expected term (years) 5.9 6.0 Expected volatility 79.9 - 81.9% 82.0 % Risk-free interest rate 2.4 - 2.6% 2.6 % Expected dividend yield — — |
Net Loss per Share (Tables)
Net Loss per Share (Tables) | 3 Months Ended |
Mar. 31, 2019 | |
Earnings Per Share [Abstract] | |
Calculation of Basic and Diluted Net Loss per Share | The following table sets forth the calculation of basic and diluted net loss per share during the periods presented (in thousands, except share and per share data): Three Months Ended March 31, 2019 2018 Numerator: Net loss $ (7,642 ) $ (4,947 ) Denominator: Weighted-average shares of common stock outstanding 19,042,524 757,399 Net loss per share, basic and diluted $ (0.40 ) $ (6.53 ) |
Anti-dilutive Outstanding Shares of Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share | The following outstanding shares of common stock equivalents were excluded from the computation of the diluted net loss per share for the periods presented because their effect would have been anti-dilutive: Three Months Ended March 31, 2019 2018 Redeemable convertible preferred stock on an if converted basis — 12,263,126 Stock options to purchase common stock 2,755,466 1,354,965 Common stock subject to future vesting 61,265 252,303 Total 2,816,731 13,870,394 |
Organization and Description _2
Organization and Description of the Business - Additional Information (Details) $ in Thousands | 3 Months Ended | |
Mar. 31, 2019USD ($)Segment | Dec. 31, 2018USD ($) | |
Organization And Description Of Business [Line Items] | ||
Number of operating segments | Segment | 1 | |
Accumulated deficit | $ | $ 56,837 | $ 49,195 |
Minimum | ||
Organization And Description Of Business [Line Items] | ||
Sufficient cash and cash equivalents available period term | 12 months |
Summary of Significant Accoun_4
Summary of Significant Accounting Policies - Additional Information (Details) | Jan. 01, 2018USD ($) |
Accounting Policies [Abstract] | |
Restricted cash amount deposited | $ 13,000 |
Summary of Significant Accoun_5
Summary of Significant Accounting Policies - Impact of Accounting Pronouncements Adoption on Balance Sheet (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Jan. 01, 2019 | Dec. 31, 2018 |
Accounting Policies [Abstract] | |||
Operating lease ROU asset | $ 4,139 | $ 4,236 | |
Operating lease liabilities, current | 804 | 774 | |
Operating lease liabilities, noncurrent | $ 6,153 | $ 6,364 | |
Deferred rent, current | $ 354 | ||
Deferred rent, noncurrent | $ 2,548 |
Fair Value Measurements - Addit
Fair Value Measurements - Additional Information (Detail) | Mar. 31, 2019USD ($) |
Fair Value Disclosures [Abstract] | |
Transfers from Level 1 to Level 2 | $ 0 |
Transfers from Level 2 to Level 1 | $ 0 |
Fair Value Measurements - Summa
Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018 |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | $ 101,014 | $ 106,406 |
Level 1 | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 32,044 | 48,848 |
Level 2 | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 68,970 | 57,558 |
Money Market Funds | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 18,349 | 23,156 |
Money Market Funds | Level 1 | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 18,349 | 23,156 |
U.S. Treasury Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 13,695 | 25,692 |
U.S. Treasury Securities | Level 1 | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 13,695 | 25,692 |
Commercial paper | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 19,357 | 19,190 |
Commercial paper | Level 2 | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 19,357 | 19,190 |
Corporate debt securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 20,538 | 20,451 |
Corporate debt securities | Level 2 | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 20,538 | 20,451 |
Government agency bonds | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | 29,075 | 17,917 |
Government agency bonds | Level 2 | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Financial Assets | $ 29,075 | $ 17,917 |
Available-for-Sale Securities -
Available-for-Sale Securities - Summary of Available-For-Sale Securities Recorded in Cash and Cash Equivalents or Marketable Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018 |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Amortized Cost | $ 82,619 | |
Fair Value | 82,664 | |
Fair Value, Measurements, Recurring | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Amortized Cost | 100,969 | $ 106,427 |
Unrealized Gains | 45 | 4 |
Unrealized Losses | (25) | |
Fair Value | 101,014 | 106,406 |
Fair Value, Measurements, Recurring | Money Market Funds | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Amortized Cost | 18,349 | 23,156 |
Fair Value | 18,349 | 23,156 |
Fair Value, Measurements, Recurring | U.S. Treasury Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Amortized Cost | 13,691 | 25,698 |
Unrealized Gains | 4 | |
Unrealized Losses | (6) | |
Fair Value | 13,695 | 25,692 |
Fair Value, Measurements, Recurring | Commercial paper | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Amortized Cost | 19,342 | 19,203 |
Unrealized Gains | 15 | |
Unrealized Losses | (13) | |
Fair Value | 19,357 | 19,190 |
Fair Value, Measurements, Recurring | Corporate debt securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Amortized Cost | 20,521 | 20,449 |
Unrealized Gains | 17 | 4 |
Unrealized Losses | (2) | |
Fair Value | 20,538 | 20,451 |
Fair Value, Measurements, Recurring | Government agency bonds | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Amortized Cost | 29,066 | 17,921 |
Unrealized Gains | 9 | |
Unrealized Losses | (4) | |
Fair Value | $ 29,075 | $ 17,917 |
Available-for-Sale Securities_2
Available-for-Sale Securities - Summary of Amortized Cost and Estimated Fair Value of Available-for-sale Securities by Contractual Maturity (Details) $ in Thousands | Mar. 31, 2019USD ($) |
Marketable securities maturing, Amortized Cost: | |
In one year or less, Amortized Cost | $ 82,619 |
Total marketable securities, Amortized Cost | 82,619 |
Marketable securities maturing, Estimated Fair Value: | |
In one year or less, Estimated Fair Value | 82,664 |
Total marketable securities, Estimated Fair Value | $ 82,664 |
Balance Sheet Components - Prop
Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018 |
Property Plant And Equipment [Line Items] | ||
Total property and equipment | $ 5,987 | $ 5,530 |
Less accumulated depreciation and amortization | (1,141) | (935) |
Property and equipment, net | 4,846 | 4,595 |
Leasehold Improvements | ||
Property Plant And Equipment [Line Items] | ||
Total property and equipment | 3,268 | 3,268 |
Furniture, Laboratory and Office Equipment | ||
Property Plant And Equipment [Line Items] | ||
Total property and equipment | 2,489 | 2,043 |
Computer Equipment | ||
Property Plant And Equipment [Line Items] | ||
Total property and equipment | $ 230 | $ 219 |
Balance Sheet Components - Addi
Balance Sheet Components - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | ||
Depreciation expense | $ 0.2 | $ 0.1 |
Balance Sheet Components - Accr
Balance Sheet Components - Accrued Liabilities (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018 |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | ||
Accrued preclinical and research costs | $ 1,128 | $ 1,146 |
Accrued clinical costs | 528 | 434 |
Accrued employee-related costs | 554 | 736 |
Accrued professional services | 90 | 138 |
Other | 106 | 224 |
Total accrued liabilities | $ 2,406 | $ 2,678 |
Operating Lease - Additional In
Operating Lease - Additional Information (Details) - South San Francisco, California [Member] | 3 Months Ended |
Mar. 31, 2019ft² | |
Area of lease | 24,357 |
Lease Expiration Date | Feb. 28, 2025 |
Operating Lease - Details of Ri
Operating Lease - Details of Right-of-Use Assets and Lease Liabilities (Details) - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2019 | Jan. 01, 2019 | |
Lessee Disclosure [Abstract] | ||
Cash paid for operating lease liabilities | $ 181 | |
Remaining lease term | 5 years 11 months 1 day | |
Discount rate | 10.00% | |
2019 | $ 1,095 | |
2020 | 1,497 | |
2021 | 1,542 | |
2022 | 1,588 | |
2023 | 1,635 | |
2024 | 1,684 | |
Thereafter | 282 | |
Total undiscounted lease payments | 9,323 | |
Less: imputed interest | (2,366) | |
Total lease liabilities | 6,957 | |
Operating lease liabilities, current | 804 | $ 774 |
Operating lease liabilities, noncurrent | 6,153 | $ 6,364 |
Total operating lease liabilities | $ 6,957 |
Operating Lease - Schedule of F
Operating Lease - Schedule of Future Minimum Lease Payments (Details) $ in Thousands | Dec. 31, 2018USD ($) |
Year ending December 31: | |
2019 | $ 1,453 |
2020 | 1,497 |
2021 | 1,542 |
2022 | 1,588 |
2023 | 1,635 |
Thereafter | 1,966 |
Total future minimum lease payments | $ 9,681 |
Stock-Based Compensation - Addi
Stock-Based Compensation - Additional Information (Details) - USD ($) | 3 Months Ended | 10 Months Ended | ||
Mar. 31, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Jun. 30, 2018 | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Number of options granted | 578,000 | |||
Maximum number of shares issued upon exercise of incentive stock options | 1,104,476 | 1,104,476 | ||
Common stock, shares issued | 19,118,421 | 19,118,421 | 19,114,421 | |
Weighted average grant date fair value of options granted | $ 22.50 | |||
Total intrinsic value of exercised stock options | $ 78,000 | |||
Early Exercise Stock Purchase Agreements | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Vesting period | 36 months | |||
Nonvested common shares outstanding | 56,038 | 56,038 | 68,349 | |
Percentage of underlying option shares whose right to purchase lapses after applicable vesting commencement date | 25.00% | |||
Right to repurchase shares underlying shares | 0.0208 | |||
Restricted Stock | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Vesting period | 4 years | |||
Nonvested common shares outstanding | 5,227 | 5,227 | 20,908 | |
2018 Equity Incentive Plan | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Shares available for future issuance | 2,179,866 | 2,179,866 | ||
Number of shares will increase automatically through every year on specified date | --01-01 | |||
Number of shares increase automatically continuing through maximum period | beginning on January 1, 2019 and continuing through and including January 1, 2028 | |||
2018 Equity Incentive Plan | Common Stock | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Maximum number of shares available for issuance | 1,600,692 | 1,600,692 | ||
Increase in number of shares reserved for issuance as percentage of total number of shares of capital stock outstanding on last date of preceding calendar year | 5.00% | |||
2018 Equity Incentive Plan | Maximum [Member] | Common Stock | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Maximum number of shares available for issuance | 4,000,000 | 4,000,000 | ||
2018 Equity Incentive Plan | Employee options | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Number of options granted | 663,621 | |||
2018 Equity Incentive Plan | Restricted Stock Units | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Number of RSU granted | 10,189 | |||
2018 Equity Incentive Plan | Incentive Stock Options | Maximum [Member] | Common Stock | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Maximum number of shares issued upon exercise of incentive stock options | 12,500,000 | 12,500,000 | ||
2015 Equity Incentive Plan | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Vesting period | 4 years | |||
Options to purchase of common stock outstanding | 2,091,845 | 2,091,845 | ||
Weighted average grant date fair value of options granted | $ 15.79 | |||
Total intrinsic value of exercised stock options | $ 78,000 | |||
2015 Equity Incentive Plan | Maximum [Member] | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Options granted expiry period | 10 years | |||
2018 Employee Stock Purchase Plan | Common Stock | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Shares available for future issuance | 391,144 | 391,144 | 200,000 | |
Common stock, shares issued | 0 | 0 | ||
Authorized an offering beginning period | Nov. 16, 2018 | |||
Authorized an offering ending period | May 15, 2019 | |||
2018 Employee Stock Purchase Plan | Maximum [Member] | Common Stock | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Percentage of annual increase in number of common stock shares | 1.00% | |||
Annual increase in number of common stock shares | 375,000 | |||
Option price per share of common stock at fair market value | 85.00% |
Stock-Based Compensation - Summ
Stock-Based Compensation - Summary of Activity under Stock Option Plan and Related Information (Details) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |
Mar. 31, 2019USD ($)$ / sharesshares | Dec. 31, 2018USD ($)$ / sharesshares | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||
Number of options outstanding, Outstanding, Beginning balance | shares | 2,181,466 | |
Number of options outstanding, Options granted | shares | 578,000 | |
Number of options outstanding, Options exercised | shares | (4,000) | |
Number of options outstanding, Outstanding, Ending balance | shares | 2,755,466 | 2,181,466 |
Number of options outstanding, options vested and exercisable | shares | 1,104,476 | |
Weighted average exercise price, Outstanding, Beginning balance | $ / shares | $ 3.80 | |
Weighted average exercise price, Options granted | $ / shares | 22.50 | |
Weighted average exercise price, Options exercised | $ / shares | 0.90 | |
Weighted average exercise price, Outstanding, Ending balance | $ / shares | 7.73 | $ 3.80 |
Weighted average exercise price, options vested and exercisable | $ / shares | $ 2.93 | |
Weighted average remaining contractual term, Outstanding, Beginning balance | 8 years 8 months 12 days | 8 years 8 months 12 days |
Weighted average remaining contractual term,options vested and exercisable | 7 years 10 months 24 days | |
Aggregate intrinsic value, Outstanding, Beginning balance | $ | $ 43,189 | |
Aggregate intrinsic value, Options exercised | $ | 78 | |
Aggregate intrinsic value, Outstanding, Ending balance | $ | 30,395 | $ 43,189 |
Aggregate intrinsic value, options vested and exercisable | $ | $ 16,468 |
Stock-Based Compensation - Su_2
Stock-Based Compensation - Summarizes of Activity of Nonvested Restricted Stock (Details) - Restricted Stock | 3 Months Ended |
Mar. 31, 2019shares | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
Nonvested beginning balance | 20,908 |
Number of Shares Outstanding, Vested | (15,681) |
Nonvested ending balance | 5,227 |
Stock-Based Compensation - Stoc
Stock-Based Compensation - Stock-Based Compensation Recognized (Details) - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||
Total stock-based compensation expense | $ 901 | $ 126 |
Research and Development Expense | ||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||
Total stock-based compensation expense | 447 | 59 |
General and Administrative Expense | ||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||
Total stock-based compensation expense | $ 454 | $ 67 |
Stock-Based Compensation - Unre
Stock-Based Compensation - Unrecognized Stock-based Compensation Cost and Estimated Weighted Average Amortization Period (Details) $ in Thousands | 3 Months Ended |
Mar. 31, 2019USD ($) | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |
Unrecognized compensation cost | $ 12,245 |
Employee options | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |
Unrecognized compensation cost | $ 12,243 |
Weighted average remaining amortization period (years) | 2 years 10 months 24 days |
Nonemployee options | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | |
Unrecognized costs of unvested options awarded | $ 2 |
Weighted average remaining amortization period (years) | 2 months 12 days |
Stock-Based Compensation - Fair
Stock-Based Compensation - Fair Value of Employee Stock Options Granted is Calculated Using Black Scholes Option Pricing Model with Weighted Average Assumptions (Details) | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||
Expected term (years) | 5 years 10 months 24 days | 6 years 1 month 6 days |
Expected volatility | 82.00% | |
Expected volatility, Minimum | 79.90% | |
Expected volatility, Maximum | 81.90% | |
Risk-free interest rate | 2.60% | |
Risk-free interest rate, Minimum | 2.40% | |
Risk-free interest rate, Maximum | 2.60% |
Income Taxes - Additional Infor
Income Taxes - Additional Information (Details) - USD ($) | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Income Tax Disclosure [Abstract] | ||
Income tax provision | $ 0 | $ 0 |
Research and development tax credit as a reduction of payroll expenses | $ 93,000 |
Net Loss Per Share - Calculatio
Net Loss Per Share - Calculation of Basic and Diluted Net Loss per Share (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Numerator: | ||
Net loss | $ (7,642) | $ (4,947) |
Denominator: | ||
Weighted-average shares of common stock outstanding | 19,042,524 | 757,399 |
Net loss per common share, basic and diluted | $ (0.40) | $ (6.53) |
Net Loss Per Share - Anti-dilut
Net Loss Per Share - Anti-dilutive Outstanding Shares of Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share (Details) - shares | 3 Months Ended | |
Mar. 31, 2019 | Mar. 31, 2018 | |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Anti-dilutive securities excluded from computation of diluted net loss per share | 2,816,731 | 13,870,394 |
Redeemable Convertible Preferred Stock on an if Converted Basis | ||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Anti-dilutive securities excluded from computation of diluted net loss per share | 12,263,126 | |
Stock Options to Purchase Common Stock | ||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Anti-dilutive securities excluded from computation of diluted net loss per share | 2,755,466 | 1,354,965 |
Common stock subject to future vesting [Member] | ||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Anti-dilutive securities excluded from computation of diluted net loss per share | 61,265 | 252,303 |