Document and Entity Information - shares |
6 Months Ended | |
|---|---|---|
Jun. 30, 2019 |
Aug. 06, 2019 |
|
| Document And Entity Information [Abstract] | ||
| Document Type | 10-Q | |
| Amendment Flag | false | |
| Document Period End Date | Jun. 30, 2019 | |
| Document Fiscal Year Focus | 2019 | |
| Document Fiscal Period Focus | Q2 | |
| Trading Symbol | FTSV | |
| Entity Registrant Name | Forty Seven, Inc. | |
| Entity Central Index Key | 0001667633 | |
| Current Fiscal Year End Date | --12-31 | |
| Entity Filer Category | Non-accelerated Filer | |
| Entity Small Business | true | |
| Entity Emerging Growth Company | true | |
| Entity Ex Transition Period | true | |
| Entity Common Stock, Shares Outstanding | 42,215,143 | |
| Entity Shell Company | false | |
| Entity Current Reporting Status | Yes | |
| Entity File Number | 001-38554 | |
| Entity Tax Identification Number | 474065674 | |
| Entity Address, Address Line One | 1490 O’Brien Drive | |
| Entity Address, Address Line Two | Suite A | |
| Entity Address, City or Town | Menlo Park | |
| Entity Address, State or Province | California | |
| Entity Address, Postal Zip Code | 94025 | |
| City Area Code | 650 | |
| Local Phone Number | 352-4150 |
| X | ||||||||||
- Definition If the value is true, then the document is an amendment to previously-filed/accepted document. No definition available.
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- Definition Area code of city No definition available.
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- Definition End date of current fiscal year in the format --MM-DD. No definition available.
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- Definition This is focus fiscal period of the document report. For a first quarter 2006 quarterly report, which may also provide financial information from prior periods, the first fiscal quarter should be given as the fiscal period focus. Values: FY, Q1, Q2, Q3, Q4, H1, H2, M9, T1, T2, T3, M8, CY. No definition available.
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- Definition This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006. No definition available.
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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. No definition available.
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- Definition The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'. No definition available.
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- Definition Address Line 1 such as Building Name, Street Name No definition available.
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- Definition Address Line 2 such as Suite No. No definition available.
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- Definition Name of the City or Town No definition available.
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- Definition Code for the postal or zip code No definition available.
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- Definition Name of the state or province. No definition available.
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- Definition A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument. No definition available.
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- Definition Indicate 'Yes' or 'No' whether registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. This information should be based on the registrant's current or most recent filing containing the related disclosure. No definition available.
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- Definition Indicate if registrant meets the emerging growth company criteria. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate if registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen. No definition available.
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- Definition Indicate whether the registrant is one of the following: (1) Large Accelerated Filer, (2) Accelerated Filer, (3) Non-accelerated Filer, (4) Smaller Reporting Company (Non-accelerated), (5) Smaller Reporting Accelerated Filer or (6) Smaller Reporting Company and Large Accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate if company meets the shell company criteria: a company with no or nominal operations, and with no or nominal assets or assets consisting solely of cash and cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicates that the company is a smaller reporting company with both a public float and revenues of less than $75 million. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Local phone number for entity. No definition available.
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- Definition Trading symbol of an instrument as listed on an exchange. No definition available.
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- Definition Document and entity information. No definition available.
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- Definition Deferred grant funding current. No definition available.
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- Definition Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of noncurrent assets classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of long-term debt classified as other, payable after one year or the operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Operating expenses: | ||||
| Research and development | $ 18,829 | $ 13,596 | $ 37,955 | $ 24,749 |
| General and administrative | 5,057 | 3,362 | 9,641 | 7,205 |
| Total operating expenses | 23,886 | 16,958 | 47,596 | 31,954 |
| Loss from operations | (23,886) | (16,958) | (47,596) | (31,954) |
| Interest and other income, net | 680 | 236 | 1,374 | 457 |
| Net loss | (23,206) | (16,722) | (46,222) | (31,497) |
| Unrealized gains on available-for-sale securities | 41 | 43 | 141 | 16 |
| Comprehensive loss | $ (23,165) | $ (16,679) | $ (46,081) | $ (31,481) |
| Net loss per share, basic and diluted | $ (0.74) | $ (2.52) | $ (1.48) | $ (4.76) |
| Shares used in computing net loss per share, basic and diluted | 31,355,135 | 6,636,862 | 31,261,182 | 6,618,736 |
| X | ||||||||||
- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business). No definition available.
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. No definition available.
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- References No definition available.
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| X | ||||||||||
- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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| X | ||||||||||
- Definition Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS). No definition available.
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Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands |
Total |
Convertible Preferred Stock |
Common Stock |
Additional Paid-in Capital |
Accumulated Other Comprehensive Income (Loss) |
Accumulated Deficit |
|||
|---|---|---|---|---|---|---|---|---|---|
| Beginning balance at Dec. 31, 2017 | $ 83,462 | $ 149,397 | $ 1 | $ 3,507 | $ (44) | $ (69,399) | |||
| Beginning balance, shares at Dec. 31, 2017 | 16,215,896 | 6,751,157 | |||||||
| Settlement of fractional shares from reverse stock split, shares | (15) | ||||||||
| Vesting of early exercised stock options | 13 | 13 | |||||||
| Stock-based compensation | 431 | 431 | |||||||
| Repurchase of common stock, shares | (41,935) | ||||||||
| Net loss | (14,775) | (14,775) | |||||||
| Other comprehensive income (loss) | (27) | (27) | |||||||
| Ending balance at Mar. 31, 2018 | 69,104 | $ 149,397 | $ 1 | 3,951 | (71) | (84,174) | |||
| Ending balance, shares at Mar. 31, 2018 | 16,215,896 | 6,709,207 | |||||||
| Beginning balance at Dec. 31, 2017 | 83,462 | $ 149,397 | $ 1 | 3,507 | (44) | (69,399) | |||
| Beginning balance, shares at Dec. 31, 2017 | 16,215,896 | 6,751,157 | |||||||
| Net loss | (31,497) | ||||||||
| Other comprehensive income (loss) | 16 | ||||||||
| Ending balance at Jun. 30, 2018 | 53,267 | $ 149,397 | $ 1 | 4,793 | (28) | (100,896) | |||
| Ending balance, shares at Jun. 30, 2018 | 16,215,896 | 6,737,837 | |||||||
| Beginning balance at Mar. 31, 2018 | 69,104 | $ 149,397 | $ 1 | 3,951 | (71) | (84,174) | |||
| Beginning balance, shares at Mar. 31, 2018 | 16,215,896 | 6,709,207 | |||||||
| Issuance of common stock for exercise of stock options | 55 | 55 | |||||||
| Issuance of common stock for exercise of stock options, shares | 28,630 | ||||||||
| Vesting of early exercised stock options | 171 | 171 | |||||||
| Stock-based compensation | 616 | 616 | |||||||
| Net loss | (16,722) | (16,722) | |||||||
| Other comprehensive income (loss) | 43 | 43 | |||||||
| Ending balance at Jun. 30, 2018 | 53,267 | $ 149,397 | $ 1 | 4,793 | (28) | (100,896) | |||
| Ending balance, shares at Jun. 30, 2018 | 16,215,896 | 6,737,837 | |||||||
| Beginning balance at Dec. 31, 2018 | 133,221 | [1] | $ 3 | 273,069 | (82) | (139,769) | |||
| Beginning balance, shares at Dec. 31, 2018 | 31,079,150 | ||||||||
| Issuance of common stock for exercise of stock options | 789 | 789 | |||||||
| Issuance of common stock for exercise of stock options, shares | 174,793 | ||||||||
| Issuance of common stock pursuant to the ESPP | 588 | 588 | |||||||
| Issuance of common stock pursuant to the ESPP, shares | 44,656 | ||||||||
| Vesting of early exercised stock options | 113 | 113 | |||||||
| Stock-based compensation | 1,104 | 1,104 | |||||||
| Net loss | (23,016) | (23,016) | |||||||
| Other comprehensive income (loss) | 100 | 100 | |||||||
| Ending balance at Mar. 31, 2019 | 112,899 | $ 3 | 275,663 | 18 | (162,785) | ||||
| Ending balance, shares at Mar. 31, 2019 | 31,298,599 | ||||||||
| Beginning balance at Dec. 31, 2018 | 133,221 | [1] | $ 3 | 273,069 | (82) | (139,769) | |||
| Beginning balance, shares at Dec. 31, 2018 | 31,079,150 | ||||||||
| Net loss | (46,222) | ||||||||
| Other comprehensive income (loss) | 141 | ||||||||
| Ending balance at Jun. 30, 2019 | 91,484 | $ 3 | 277,413 | 59 | (185,991) | ||||
| Ending balance, shares at Jun. 30, 2019 | 31,432,322 | ||||||||
| Beginning balance at Mar. 31, 2019 | 112,899 | $ 3 | 275,663 | 18 | (162,785) | ||||
| Beginning balance, shares at Mar. 31, 2019 | 31,298,599 | ||||||||
| Issuance of common stock for exercise of stock options | 612 | 612 | |||||||
| Issuance of common stock for exercise of stock options, shares | 133,723 | ||||||||
| Vesting of early exercised stock options | 13 | 13 | |||||||
| Stock-based compensation | 1,125 | 1,125 | |||||||
| Net loss | (23,206) | (23,206) | |||||||
| Other comprehensive income (loss) | 41 | 41 | |||||||
| Ending balance at Jun. 30, 2019 | $ 91,484 | $ 3 | $ 277,413 | $ 59 | $ (185,991) | ||||
| Ending balance, shares at Jun. 30, 2019 | 31,432,322 | ||||||||
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| X | ||||||||||
- Definition Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation for stock options. No definition available.
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| X | ||||||||||
- Definition Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Number of shares issued which are neither cancelled nor held in the treasury. No definition available.
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| X | ||||||||||
- Definition Number of shares issued during the period as a result of an employee stock purchase plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Reduction in the number of shares during the period as a result of a reverse stock split. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Aggregate change in value for stock issued during the period as a result of employee stock purchase plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Value of stock issued as a result of the exercise of stock options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands |
6 Months Ended | |
|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Cash flows from operating activities: | ||
| Net loss | $ (46,222) | $ (31,497) |
| Adjustments to reconcile net loss to net cash used in operating activities: | ||
| Stock-based compensation | 2,229 | 1,047 |
| Depreciation and amortization | 233 | 193 |
| Amortization of right-of-use assets | 461 | 0 |
| Accretion of discounts on marketable securities | (730) | (180) |
| Realized gain on sale of available-for-sale securities | (4) | 0 |
| Change in fair value of embedded derivative | 12 | 0 |
| Changes in operating assets and liabilities: | ||
| Prepaid expenses and other current assets | (5,026) | 853 |
| Other assets | 1,620 | (1,412) |
| Accounts payable | 3,720 | (603) |
| Accrued liabilities | 571 | 762 |
| Deferred grant funding | 997 | 2,806 |
| Lease related liabilities | (530) | (56) |
| Net cash used in operating activities | (42,669) | (28,087) |
| Cash flows from investing activities: | ||
| Purchases of property and equipment | (70) | 0 |
| Purchases of available-for-sale securities | (68,819) | (16,368) |
| Proceeds from sales of available-for-sale securities | 3,996 | 0 |
| Proceeds from maturities of available-for-sale securities | 112,727 | 35,365 |
| Net cash provided by investing activities | 47,834 | 18,997 |
| Cash flows from financing activities: | ||
| Payments of deferred offering costs | (143) | (2,368) |
| Proceeds from issuance of common stock upon ESPP purchase | 588 | 0 |
| Proceeds from issuance of common stock upon exercise of stock options | 1,402 | 155 |
| Net cash provided by (used in) financing activities | 1,847 | (2,213) |
| Net increase (decrease) in cash and cash equivalents | 7,012 | (11,303) |
| Cash and cash equivalents — beginning of period | 10,837 | 24,417 |
| Cash and cash equivalents — end of period | 17,849 | 13,114 |
| Noncash investing and financing activities: | ||
| Purchase of property and equipment through accounts payable and accruals | 91 | 0 |
| Deferred offering costs included in accounts payable and accrued liabilities | 326 | 1,697 |
| Lease liability obtained in exchange for right-of-use asset | $ 712 | $ 0 |
| X | ||||||||||
- Definition Deferred offering costs included in accounts payable and accrued liabilities. No definition available.
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- Definition Increase (decrease) in lease-related liabilities. No definition available.
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- Definition Operating lease right of use asset amortization. No definition available.
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- Definition The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. No definition available.
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- Definition Future cash outflow to pay for purchases of fixed assets that have occurred. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The increase (decrease) during the reporting period in the aggregate amount of expenses incurred but not yet paid. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Change during the period in carrying value for all deferred liabilities due within one year or operating cycle. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of increase (decrease) in operating assets classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase (decrease) in prepaid expenses, and assets classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- References No definition available.
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- Definition The cash outflow for cost incurred directly with the issuance of an equity security. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cash outflow to acquire debt and equity securities not classified as either held-to-maturity securities or trading securities which would be classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cash inflow from the additional capital contribution to the entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash inflow from sale, maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase in right-of-use asset obtained in exchange for operating lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Description of Business |
6 Months Ended | ||
|---|---|---|---|
Jun. 30, 2019 | |||
| Organization Consolidation And Presentation Of Financial Statements [Abstract] | |||
| Basis of Presentation |
The Company is a clinical-stage immuno-oncology company focused on developing novel checkpoint therapies to activate macrophages in the fight against cancer. Forty Seven was founded based on the insight that blocking CD47, a key signaling molecule that is over-expressed on cancer cells, renders tumors susceptible to macrophages and the innate immune system. By harnessing macrophages, the Company believes that its lead product candidate, 5F9, dosed as a monotherapy and in combination with marketed cancer therapies, can transform the treatment of cancer. Liquidity In the course of its development activities, the Company has sustained operating losses and expects to continue to generate operating losses for the foreseeable future. The Company’s ultimate success depends on the outcome of its research and development activities. The Company had cash, cash equivalents and short-term investments of $99.0 million as of June 30, 2019. Since inception through June 30, 2019, the Company has incurred cumulative net losses of $186.0 million. Management expects to incur additional losses in the future to conduct product research and development and recognizes the need to raise additional capital to fully implement its business plan. The Company intends to raise such capital through the issuance of additional equity financing and/or third-party collaboration funding. However, if such financing is not available at adequate levels, the Company will need to reevaluate its operating plan and may be required to delay the development of its products. The Company expects that its cash, cash equivalents and short-term investments will be sufficient to fund operating expenses and capital expenditure requirements for a period of at least one year from the date these interim condensed financial statements are filed with the Securities and Exchange Commission (“SEC”). |
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- Definition The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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Summary of Significant Accounting Policies |
6 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Accounting Policies [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Significant Accounting Policies |
Basis of Presentation The interim condensed financial statements are unaudited. The unaudited interim condensed financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position, results of operations and cash flows for the periods presented. The results of operations for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any other future annual or interim period. The condensed balance sheet as of December 31, 2018 included herein was derived from the audited financial statements as of that date. These condensed financial statements should be read in conjunction with the Company's audited financial statements and related notes as set forth in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2018, as filed with the SEC on March 28, 2019. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying financial statements include but are not limited to the fair value of common stock, the fair value of stock options, the fair value of investments, income tax uncertainties, lease liability, and certain accruals. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates. Fair Value Measurement Assets and liabilities recorded at fair value on a recurring basis in the 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. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active; 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. Leases The Company adopted Accounting Standards Update (ASU) No. 2016-02, Leases on January 1, 2019 using the modified retrospective method. For its operating leases in excess of 12 months, the Company recognizes a right-of-use asset and a lease liability on its balance sheet. The lease liability is determined as the present value of future lease payments using an estimated rate of interest that the Company would pay to borrow equivalent funds on a collateralized basis at the adoption date for the existing lease and at lease commencement date for new leases. The right-of-use asset is based on the liability adjusted for any prepaid or deferred rent, and lease incentives, as applicable. The lease term at the commencement date is determined by considering whether renewal options and termination options are reasonably assured of exercise. Rent expense for the operating leases is recognized on a straight-line basis over the lease term and is included in operating expenses on the statements of operations and comprehensive loss. Variable lease payments include lease operating expenses. The accompanying condensed financial statements as of and for the three and six months ended June 30, 2019 are presented under Topic 842. The prior periods continue to be reported in accordance with previous lease guidance, ASC Topic 840, Leases. The Company elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allows the Company to carry forward the historical lease classification of the leases in place as of January 1, 2019. As allowed under Topic 842, the Company has elected to not separate lease and nonlease components. The Company has also elected to not apply the recognition requirement of Topic 842 to leases with a term of 12 months or less. The impact of the adoption of Topic 842 on the accompanying condensed balance sheet as of January 1, 2019 was as follows:
The adjustments due to the adoption of Topic 842 related to the recognition of an operating lease right-of-use asset and lease liability for the Company's existing property operating lease and the derecognition of the deferred rent recognized under Topic 840. There was no impact on the Company’s statement of operations and comprehensive loss from the adoption and no cumulative-effect adjustment to the beginning accumulated deficit. |
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- References No definition available.
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- Definition The entire disclosure for all significant accounting policies of the reporting entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fair Value Measurements |
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| Fair Value Disclosures [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Fair Value Measurements |
The Company measures and records its cash equivalents and short-term investments at fair value. Money market funds are measured at fair value on a recurring basis using quoted prices and are classified as a Level 1 input. Short-term investments are measured at fair value based on inputs other than quoted prices that are derived from observable market data and are classified as Level 2 inputs. There were no transfers between Levels 1, 2 or 3 for any of the periods presented. All of the investments held as of June 30, 2019 and December 31, 2018 had maturities of less than one year. There were no significant realized gains or losses on investments for the three and six months ended June 30, 2019 and 2018. Any identified unrealized losses were deemed to be temporary. The Company does not intend to sell its securities that are in an unrealized loss position, if any, and it is unlikely that the Company will be required to sell its securities before recovery of their amortized cost basis, which may be maturity. The fair value and amortized cost of cash equivalents and available-for-sale securities by major security type as of June 30, 2019 and December 31, 2018 are presented in the following tables:
The Company’s contingent milestone payments in its agreement with the Leukemia & Lymphoma Society, Inc. (“LLS”) were concluded to be an embedded derivative. The embedded derivative contains unobservable inputs that are supported by little or no market activity at the measurement date. Accordingly, the Company’s embedded derivative is measured at fair value on a recurring basis using unobservable inputs that are classified as Level 3 inputs. The Company recorded a liability for the derivative of approximately $0.3 million, as part of other long-term liabilities as of June 30, 2019 and December 31, 2018. Refer to Note 5 for the valuation techniques and assumptions used in estimating the fair value of the embedded derivative. The change in fair value of the embedded derivative is presented in the following table:
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- References No definition available.
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- Definition The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Sheet Components |
6 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Jun. 30, 2019 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Balance Sheet Related Disclosures [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Balance Sheet Components |
Accrued Liabilities Accrued liabilities consist of the following:
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- References No definition available.
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- Definition The entire disclosure for supplemental balance sheet disclosures, including descriptions and amounts for assets, liabilities, and equity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Research and License Agreements |
6 Months Ended | ||
|---|---|---|---|
Jun. 30, 2019 | |||
| Research And License Agreements [Abstract] | |||
| Research and License Agreements |
California Institute of Regenerative Medicine Grants In January 2017, the Company was awarded a research grant from the California Institute of Regenerative Medicine (“CIRM”). The CIRM grant stipulates various milestone-based payments to the Company with the total award of $10.2 million over a period of four years. During the three and six months ended June 30, 2019, the Company received $2.0 million related to this grant. As of June 30, 2019 and December 31, 2018, the Company had received $9.2 million and $7.2 million under the award, respectively. In November 2017, the Company was awarded a second research grant from CIRM for a separate clinical trial study. The total amount of the research grant awarded was $5.0 million in various milestone-based payments over a period of five years. During 2018, the award was amended to $3.2 million in various-milestone payments over a period of five years, as was provided for under the terms of the original award because the Company opted not to expand the patient population participating in the study. During the three and six months ended June 30, 2019, the Company received $0.7 million related to this grant. As of June 30, 2019 and December 31, 2018, the Company had received $3.1 million and $2.4 million under the award, respectively. Under the terms of the CIRM grants, the Company is obligated to pay royalties and licensing fees based on a low single digit royalty percentage on net sales of CIRM-funded product candidates or CIRM-funded technology. The Company has the option to decline any and all amounts awarded by CIRM. As an alternative to royalty payments, the Company has the option to convert the award to a loan. No such election has been made as of the date of the issuance of these financial statements. In the event that the Company terminates a CIRM-funded clinical trial, it will be obligated to repay the remaining CIRM funds on hand. Leukemia & Lymphoma Society Grant In March 2017, the Company entered into an agreement with the LLS and amended the agreement to include an additional study in June 2018. The LLS research grant stipulates various milestone-based payments with a total award of $4.2 million through December 2019. During the three and six months ended June 30, 2019, the Company did not receive any payments related to this grant. As of June 30, 2019 and December 31, 2018, the Company had received $3.9 million under the award. The Company could be required in the future to pay amounts to LLS upon reaching certain development and regulatory approval milestones as well as a low single digit percentage royalty rate on net sales, up to a maximum of $15.0 million in total. The Company concluded that the contingent milestone payments were an embedded derivative and the Company recorded a liability for the derivative of approximately $0.3 million, as part of other long-term liabilities as of June 30, 2019 and December 31, 2018. The value of the embedded derivative was estimated using the probability-adjusted and discounted future milestone payments. In July 2019, the Company entered into an amendment of its agreement with LLS to further advance the treatment of myelodysplastic syndromes (“MDS”). Under the collaboration, the Company is eligible for up to $3.0 million in additional milestone payments from LLS upon the achievement of certain clinical or regulatory milestones in addition to the $4.2 million award that the Company is eligible for pursuant to the March 2017 agreement. Pursuant to the amendment, potential future payments by the Company to LLS upon reaching certain development and regulatory approval milestones on the additional funding could be up to $6.0 million in total. The Company recognizes research grants as a reduction of research and development expense when the eligible costs are incurred. Under both CIRM and LLS grants, the Company recognized a total of $0.9 million and $1.9 million as a reduction to research and development expenses for research grants for the three months ended June 30, 2019 and 2018, respectively. The Company recognized a total of $2.0 million and $3.4 million as a reduction to research and development expenses for research grants for the six months ended June 30, 2019 and 2018, respectively.
Merck Collaboration Agreement In January 2018, the Company entered into a clinical trial collaboration and supply agreement with Ares Trading S.A, a subsidiary of Merck KGaA (“Merck”), to evaluate 5F9 combined with Merck’s cancer immunotherapy, avelumab, in a Phase 1b clinical trial in patients with ovarian cancer. Pursuant to the agreement, the parties will jointly pay for the cost of the study. As of June 30, 2019, the Company recorded a receivable of $0.9 million from Merck for reimbursement of research and development costs incurred. Reimbursement under this collaboration agreement is recorded as a reduction to research and development expense. For the three months ended June 30, 2019 and 2018, the Company recognized $0.3 million and $0.4 million, respectively, as a reduction to research and development expenses under this collaboration agreement. For the six months ended June 30, 2019 and 2018, the Company recognized $0.9 million and $0.6 million, respectively, as a reduction to research and development expenses under this collaboration agreement. |
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- Definition Research and license agreements. No definition available.
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- Definition The entire disclosure for collaborative arrangements in which the entity is a participant, including a) information about the nature and purpose of such arrangements; b) its rights and obligations thereunder; c) the accounting policy for collaborative arrangements; and d) the income statement classification and amounts attributable to transactions arising from the collaborative arrangement between participants. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Leases |
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| Leases [Abstract] | |||||||||||||||||||||||||||||||||||||||||
| Leases |
6. Leases The Company leases office property and laboratory space at its headquarters in Menlo Park (the “Menlo Park Lease”) through August 2021. The lease requires monthly lease payments subject to annual increases throughout the lease term and includes a renewal option at the election of the Company to extend the lease for an additional five years. The landlord provided the Company with a tenant improvement allowance of $646,000. In April 2019, the Company entered into a sublease (the “Sublease”) to obtain 6,230 rentable square feet to expand its current headquarters through February 2021. The lease requires monthly lease payments subject to annual increases throughout the lease term. In April 2019, the Company also entered into an amendment of Menlo Park Lease to add additional space to its headquarter lease upon the expiration of the Sublease in February 2021. Under the terms of the lease amendment, the lease for the additional space will commence on March 1, 2021 and the base rent for the additional space will be approximately $36,000 per month. As of June 30, 2019, the weighted average remaining lease term was 2.1 years and the weighted average incremental borrowing rate used to determine the operating lease liabilities was 7.0%. The undiscounted future non-cancellable lease payments under the Company's operating leases are as follows:
As of June 30, 2019, the current and noncurrent portion of the lease liabilities was $1.4 million and $1.6 million. Rent expense for the operating leases was $0.3 million for the three months ended June 30, 2019 and 2018, and $0.6 million for the six months ended June 30, 2019 and 2018. Variable lease payments for operating expenses were $0.1 million for the three months ended June 30, 2019 and 2018. Variable lease payments for operating expenses were $0.3 million and $0.2 million for the six months ended June 30, 2019 and 2018, respectively. |
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- References No definition available.
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- Definition The entire disclosure for operating leases of lessee. Includes, but is not limited to, description of operating lease and maturity analysis of operating lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Stockholders' Equity |
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| Stockholders' Equity |
2015 and 2018 Equity Incentive Plans The following summarizes option activity for the six months ended June 30, 2019:
Total stock-based compensation was as follows:
Restricted Stock As of June 30, 2019 and December 31, 2018, there was $18,000 and $144,000, respectively, recorded in other long-term liabilities related to shares held by employees and directors that were subject to repurchase. A summary of restricted stock activity follows:
Employee Share Purchase Plan (ESPP) In June 2018, the Company adopted the 2018 Employee Stock Purchase Plan (“ESPP”), which became effective upon the execution of the underwriting agreement related to the IPO. The initial offering period began June 27, 2018 and will end on August 15, 2020 with purchase dates of February 15, 2019, August 15, 2019, February 15, 2020, and August 15, 2020. Each subsequent offering will be approximately 24 months long and will consist of four purchase periods with purchase dates occurring on February 15 and August 15 of each year. On each purchase date, ESPP participants will purchase shares of common stock at a price per share equal to 85% of the lesser of (1) the fair market value per share of the common stock on the offering date or (2) the fair market value of the common stock on the purchase date. Total stock-based compensation related to the ESPP for the three and six months ended June 30, 2019 was $187,000 and $415,000, respectively. Total stock-based compensation related to the ESPP for the three and six months ended June 30, 2018 was immaterial to the condensed financial statements. A total of 44,656 shares of common stock were purchased pursuant to the ESPP during the six months ended June 30, 2019 for total proceeds of $588,000. Convertible preferred stock The convertible preferred stock was temporarily reclassified to mezzanine equity as of June 30, 2018 before converting into common stock and permanent equity upon the closing of Company’s initial public offering in July 2018. |
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- References No definition available.
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- Definition The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Net Loss Per Share |
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| Earnings Per Share [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Net Loss Per Share |
The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share for the periods presented due to their anti-dilutive effect:
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- References No definition available.
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- Definition The entire disclosure for earnings per share. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Subsequent Events |
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| Subsequent Events [Abstract] | |||
| Subsequent Events |
Registration Statement on Form S-3 In July 2019, the Company filed a Registration Statement on Form S-3, as amended (file no. 333-232498), declared effective by the SEC on July 12, 2019 (the “Shelf Registration Statement”), covering the offering of up to $250 million of common stock, preferred stock, debt securities and warrants. The Company may use the Shelf Registration Statement at any time or from time to time to offer, in one or more offerings, common stock, preferred stock, debt securities and warrants. The Shelf Registration Statement included a prospectus covering the offering, issuance and sale of up to $60.0 million of shares of the Company’s common stock from time to time in “at-the-market offerings” pursuant to a Controlled Equity OfferingSM Sales Agreement (the “Sales Agreement”) entered into with Cantor Fitzgerald & Co. (the “Sales Agent”) on July 1, 2019. As of August 13, 2019, the Company had not sold any securities pursuant to the Sales Agreement. Ono License and Collaboration Agreement In July 2019, the Company entered into an exclusive license and collaboration agreement with Ono Pharmaceutical Co., Ltd., (“Ono”). Under the agreement, the Company granted Ono an exclusive license to develop, manufacture and commercialize 5F9, the Company’s monoclonal antibody against CD47, as well as other anti-CD47 antibodies controlled by the Company in Japan, South Korea, Taiwan and the ASEAN countries(the “Ono Territory”). The Company retains all rights to 5F9 and other licensed antibodies outside of the Ono Territory. Under the agreement, the parties will collaborate on the development, manufacturing and commercialization of 5F9 and other licensed antibodies. Each party will be responsible for conducting development and commercialization of licensed antibodies in its respective territory at its own cost. Further, each party will have the right to participate, at its cost, in global clinical studies of 5F9 and other licensed antibodies conducted by the other party. The Company will receive a one-time upfront payment from Ono of 1.7 billion Japanese Yen (approximately $15.7 million US Dollar based on the exchange rate at July 10, 2019) and will be eligible to receive up to an additional 11.2 billion Japanese Yen (approximately $103.3 million US Dollar based on the exchange rate at July 10, 2019) if specified future development and commercial milestones are achieved by Ono. The Company is also eligible to receive tiered percentage royalties spanning from the mid-teens to the low-twenties on future net sales of 5F9 and other licensed antibodies in the Ono Territory, subject to certain offsets. Public Offering In July 2019, pursuant to the Shelf Registration Statement the Company completed an underwritten public offering of 10,781,250 shares of its common stock, including 1,406,250 shares sold pursuant to the underwriters’ exercise of their option to purchase additional shares at a public offering price of $8.00 per share. The gross proceeds from the offering to the Company, before underwriting discounts and commissions and offering expenses, were approximately $86.3 million. |
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- References No definition available.
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- Definition The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Summary of Significant Accounting Policies (Policies) |
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| Basis of Presentation |
Basis of Presentation The interim condensed financial statements are unaudited. The unaudited interim condensed financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position, results of operations and cash flows for the periods presented. The results of operations for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any other future annual or interim period. The condensed balance sheet as of December 31, 2018 included herein was derived from the audited financial statements as of that date. These condensed financial statements should be read in conjunction with the Company's audited financial statements and related notes as set forth in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2018, as filed with the SEC on March 28, 2019. |
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| Use of Estimates |
Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying financial statements include but are not limited to the fair value of common stock, the fair value of stock options, the fair value of investments, income tax uncertainties, lease liability, and certain accruals. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates. |
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| Fair Value Measurement |
Fair Value Measurement Assets and liabilities recorded at fair value on a recurring basis in the 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. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active; 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. |
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| Leases |
Leases The Company adopted Accounting Standards Update (ASU) No. 2016-02, Leases on January 1, 2019 using the modified retrospective method. For its operating leases in excess of 12 months, the Company recognizes a right-of-use asset and a lease liability on its balance sheet. The lease liability is determined as the present value of future lease payments using an estimated rate of interest that the Company would pay to borrow equivalent funds on a collateralized basis at the adoption date for the existing lease and at lease commencement date for new leases. The right-of-use asset is based on the liability adjusted for any prepaid or deferred rent, and lease incentives, as applicable. The lease term at the commencement date is determined by considering whether renewal options and termination options are reasonably assured of exercise. Rent expense for the operating leases is recognized on a straight-line basis over the lease term and is included in operating expenses on the statements of operations and comprehensive loss. Variable lease payments include lease operating expenses. The accompanying condensed financial statements as of and for the three and six months ended June 30, 2019 are presented under Topic 842. The prior periods continue to be reported in accordance with previous lease guidance, ASC Topic 840, Leases. The Company elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allows the Company to carry forward the historical lease classification of the leases in place as of January 1, 2019. As allowed under Topic 842, the Company has elected to not separate lease and nonlease components. The Company has also elected to not apply the recognition requirement of Topic 842 to leases with a term of 12 months or less. The impact of the adoption of Topic 842 on the accompanying condensed balance sheet as of January 1, 2019 was as follows:
The adjustments due to the adoption of Topic 842 related to the recognition of an operating lease right-of-use asset and lease liability for the Company's existing property operating lease and the derecognition of the deferred rent recognized under Topic 840. There was no impact on the Company’s statement of operations and comprehensive loss from the adoption and no cumulative-effect adjustment to the beginning accumulated deficit. |
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- References No definition available.
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- Definition The entire disclosure for the basis of presentation and significant accounting policies concepts. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS). Accounting policies describe all significant accounting policies of the reporting entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Disclosure of accounting policy for fair value measurements of financial and non-financial assets, liabilities and instruments classified in shareholders' equity. Disclosures include, but are not limited to, how an entity that manages a group of financial assets and liabilities on the basis of its net exposure measures the fair value of those assets and liabilities. No definition available.
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- Definition Disclosure of accounting policy for leasing arrangement entered into by lessee. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Summary of Significant Accounting Policies (Tables) |
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| Schedule of Impact of Adoption of Topic 842 on Accompanying Condensed Balance Sheet |
The impact of the adoption of Topic 842 on the accompanying condensed balance sheet as of January 1, 2019 was as follows:
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- References No definition available.
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- Definition Tabular disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fair Value Measurements (Tables) |
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| Fair Value Disclosures [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Fair Value, Assets Measured on Recurring and Nonrecurring Basis |
The fair value and amortized cost of cash equivalents and available-for-sale securities by major security type as of June 30, 2019 and December 31, 2018 are presented in the following tables:
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| Schedule of Change in Fair Value of Embedded Derivative |
The change in fair value of the embedded derivative is presented in the following table:
|
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| X | ||||||||||
- Definition Tabular disclosure of assets measured at fair value measured on a recurring or nonrecurring basis. Includes, but is not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Sheet Components (Tables) |
6 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2019 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Balance Sheet Related Disclosures [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule of Accrued Liabilities |
Accrued liabilities consist of the following:
|
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Tabular disclosure of the components of accrued liabilities. No definition available.
|
Leases (Tables) |
6 Months Ended | ||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2019 | |||||||||||||||||||||||||||||||||||||||||
| Leases [Abstract] | |||||||||||||||||||||||||||||||||||||||||
| Schedule of Undiscounted Future Non-Cancellable Lease Payments under Company's Operating Leases |
The undiscounted future non-cancellable lease payments under the Company's operating leases are as follows:
|
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Tabular disclosure of undiscounted cash flows of lessee's operating lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to operating lease liability recognized in statement of financial position. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
Stockholders' Equity (Tables) |
6 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Jun. 30, 2019 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Equity [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Option Activity |
The following summarizes option activity for the six months ended June 30, 2019:
|
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| Schedule of Total Stock-Based Compensation |
Total stock-based compensation was as follows:
|
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| Summary of Restricted Stock Activity |
A summary of restricted stock activity follows:
|
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
Net Loss Per Share (Tables) |
6 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2019 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Earnings Per Share [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Outstanding Potentially Dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share |
The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share for the periods presented due to their anti-dilutive effect:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Tabular disclosure of securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented, by antidilutive securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
Description of Business - Additional Information (Details) - USD ($) $ in Thousands |
Jun. 30, 2019 |
Dec. 31, 2018 |
[1] | ||
|---|---|---|---|---|---|
| Organization Consolidation And Presentation Of Financial Statements [Abstract] | |||||
| Cash, cash equivalents and short-term investments | $ 99,000 | ||||
| Cumulative net losses | $ 185,991 | $ 139,769 | |||
| |||||
| X | ||||||||||
- Definition Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
Summary of Significant Accounting Policies - Schedule of Impact of Adoption of Topic 842 on Accompanying Condensed Balance Sheet (Details) - USD ($) $ in Thousands |
Jun. 30, 2019 |
Jan. 01, 2019 |
Dec. 31, 2018 |
||
|---|---|---|---|---|---|
| Assets | |||||
| Operating lease right-of-use asset | $ 2,579 | ||||
| Liabilities and stockholders' equity | |||||
| Deferred rent classified as accrued liabilities | $ 155 | ||||
| Lease liability, current | 1,397 | ||||
| Lease liability, noncurrent | $ 1,600 | ||||
| Deferred rent, noncurrent | [1] | $ 331 | |||
| Accounting Standards Update 2016-02 | |||||
| Assets | |||||
| Operating lease right-of-use asset | $ 2,328 | ||||
| Liabilities and stockholders' equity | |||||
| Lease liability, current | 968 | ||||
| Lease liability, noncurrent | 1,847 | ||||
| Accounting Standards Update 2016-02 | Adjustments due to the adoption of Topic 842 | |||||
| Assets | |||||
| Operating lease right-of-use asset | 2,328 | ||||
| Liabilities and stockholders' equity | |||||
| Deferred rent classified as accrued liabilities | (155) | ||||
| Lease liability, current | 968 | ||||
| Lease liability, noncurrent | 1,847 | ||||
| Deferred rent, noncurrent | $ (331) | ||||
| |||||
| X | ||||||||||
- Definition Accrued deferred rent current. No definition available.
|
| X | ||||||||||
- Definition Operating lease asset. No definition available.
|
| X | ||||||||||
- Definition Operating lease liabilties and stockholders equity. No definition available.
|
| X | ||||||||||
- Definition For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Fair Value Measurements - Additional Information (Details) - USD ($) |
3 Months Ended | 6 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||||
| Transfers between level 1 to Level 2 and Level 3 amount | $ 0 | $ 0 | |||
| Realized gains (losses) on investments | 0 | $ 0 | 0 | $ 0 | |
| Other Long-Term Liabilities | Leukemia & Lymphoma Society, Inc. | |||||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||||
| Derivative Liability | $ 300,000 | $ 300,000 | $ 300,000 | ||
| Maximum | |||||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||||
| Maturity of investments | 1 year | 1 year | |||
| X | ||||||||||
- Definition Fair value assets level 1 to level 2 and level 3 transfers amount. No definition available.
|
| X | ||||||||||
- Definition Maturity of investments term. No definition available.
|
| X | ||||||||||
- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Fair Value Measurements - Fair Value and Amortized Cost of Cash Equivalents and Available for Sale Securities by Major Security Type (Details) - USD ($) $ in Thousands |
Jun. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | $ 96,769 | $ 136,227 |
| Unrealized Gains | 59 | |
| Unrealized Losses | (82) | |
| Market Value | 96,828 | 136,145 |
| Level 1 | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | 15,670 | 7,959 |
| Market Value | 15,670 | 7,959 |
| Commercial Paper | Level 2 | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | 24,271 | 43,277 |
| Market Value | 24,271 | 43,277 |
| Corporate Debt Securities | Level 2 | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | 20,453 | 46,186 |
| Unrealized Gains | 24 | |
| Unrealized Losses | (54) | |
| Market Value | 20,477 | 46,132 |
| Asset-backed Securities | Level 2 | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | 16,470 | 22,842 |
| Unrealized Gains | 11 | |
| Unrealized Losses | (27) | |
| Market Value | 16,481 | 22,815 |
| US Government Debt Securities | Level 2 | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | 19,905 | 15,963 |
| Unrealized Gains | 24 | |
| Unrealized Losses | (1) | |
| Market Value | $ 19,929 | $ 15,962 |
| X | ||||||||||
- Definition Cash equivalents and available for sale securities accumulated gross unrealized gain before tax. No definition available.
|
| X | ||||||||||
- Definition Cash equivalents and available for sale securities accumulated gross unrealized loss before tax. No definition available.
|
| X | ||||||||||
- Definition Cash equivalents and available for sale securities amortized cost basis. No definition available.
|
| X | ||||||||||
- Definition Cash equivalents and available for sale securities at fair value. No definition available.
|
| X | ||||||||||
- Definition Cash equivalents fair value. No definition available.
|
| X | ||||||||||
- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Fair Value Measurements - Schedule of Change in Fair Value of Embedded Derivative (Details) - Embedded Derivative $ in Thousands |
6 Months Ended |
|---|---|
|
Jun. 30, 2019
USD ($)
| |
| Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] | |
| Fair value of embedded derivative, Beginning balance | $ 331 |
| Change in fair value of embedded derivative | 12 |
| Fair value of embedded derivative, Ending balance | $ 343 |
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
Balance Sheet Components - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands |
Jun. 30, 2019 |
Dec. 31, 2018 |
|||
|---|---|---|---|---|---|
| Accrued Liabilities Current [Abstract] | |||||
| Accrued research and development expenses | $ 6,338 | $ 5,870 | |||
| Accrued bonuses | 1,379 | 1,602 | |||
| Deferred rent, current | 155 | ||||
| Other | 2,002 | 1,417 | |||
| Total accrued liabilities | $ 9,719 | $ 9,044 | [1] | ||
| |||||
| X | ||||||||||
- Definition Accrued deferred rent current. No definition available.
|
| X | ||||||||||
- Definition Accrued research and development expenses, current. No definition available.
|
| X | ||||||||||
- Definition Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
Research and License Agreements - Additional Information (Details) - USD ($) |
1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended | |||||
|---|---|---|---|---|---|---|---|---|---|
Jul. 31, 2019 |
Nov. 30, 2017 |
Jan. 31, 2017 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
Mar. 31, 2017 |
|
| Leukemia & Lymphoma Society, Inc. ("LLS") | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Additional milestone payments to be paid upon achievement of certain clinical or regulatory milestones | $ 4,200,000 | ||||||||
| Leukemia & Lymphoma Society, Inc. ("LLS") | Maximum | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Additional milestone payments | 3,000,000 | ||||||||
| Potential future milestone payments related to certain development and regulatory approval milestones | $ 6,000,000 | ||||||||
| Leukemia & Lymphoma Society, Inc. ("LLS") | Other Long-Term Liabilities | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Derivative Liability | $ 300,000 | $ 300,000 | $ 300,000 | ||||||
| Research Grant | California Institute of Regenerative Medicine (CIRM) | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Collaborative arrangement research grant receivable | $ 10,200,000 | 2,000,000 | 2,000,000 | ||||||
| Collaborative arrangement milestone payments receivable period | 4 years | ||||||||
| Proceeds from collaborators | 9,200,000 | 7,200,000 | |||||||
| Research Grant | Leukemia & Lymphoma Society, Inc. ("LLS") | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Collaborative arrangement research grant receivable | 0 | 0 | $ 4,200,000 | ||||||
| Proceeds from collaborators | 3,900,000 | 3,900,000 | |||||||
| Research Grant | Leukemia & Lymphoma Society, Inc. ("LLS") | Maximum | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Milestone payments to be paid upon achievement of development and regulatory approval milestones | 15,000,000 | 15,000,000 | |||||||
| Research Grant | Leukemia & Lymphoma Society, Inc. ("LLS") | Other Long-Term Liabilities | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Derivative Liability | 300,000 | 300,000 | 300,000 | ||||||
| Research Grant | California Institute of Regenerative Medicine (CIRM) and Leukemia & Lymphoma Society, Inc. ("LLS") | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Reduction to research and development expenses for research grants | 900,000 | $ 1,900,000 | 2,000,000 | $ 3,400,000 | |||||
| Second Research Grant | California Institute of Regenerative Medicine (CIRM) | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Collaborative arrangement research grant receivable | $ 5,000,000 | 700,000 | 700,000 | ||||||
| Collaborative arrangement milestone payments receivable period | 5 years | ||||||||
| Proceeds from collaborators | 3,100,000 | 2,400,000 | |||||||
| Collaborative arrangement, amended research grant receivable | $ 3,200,000 | ||||||||
| Collaborative arrangement, amended milestone payments receivable period | 5 years | ||||||||
| Merck Collaboration Agreement | Ares Trading S.A | |||||||||
| Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |||||||||
| Reduction to research and development expenses for research grants | 300,000 | $ 400,000 | 900,000 | $ 600,000 | |||||
| Receivable for reimbursement of research and development costs incurred | $ 900,000 | $ 900,000 | |||||||
| X | ||||||||||
- Definition Additional milestone payments. No definition available.
|
| X | ||||||||||
- Definition Additional milestone payments to be paid upon achievement of certain clinical or regulatory milestones. No definition available.
|
| X | ||||||||||
- Definition Collaborative arrangement, amended milestone payments receivable period. No definition available.
|
| X | ||||||||||
- Definition Collaborative arrangement, amended research grant receivable. No definition available.
|
| X | ||||||||||
- Definition Collaborative arrangement milestone payments receivable period. No definition available.
|
| X | ||||||||||
- Definition Collaborative arrangement research grant receivable. No definition available.
|
| X | ||||||||||
- Definition Milestone payments to be paid upon achievement of development and regulatory approval milestones. No definition available.
|
| X | ||||||||||
- Definition Potential future milestone payments related to certain development and regulatory approval milestones. No definition available.
|
| X | ||||||||||
- Definition Receivable for reimbursement of research and development costs incurred. No definition available.
|
| X | ||||||||||
- Definition Reduction recognized to research and development expense for research grants. No definition available.
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Cash received from collaborators during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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Leases - Additional Information (Details) |
1 Months Ended | 3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|---|
|
Apr. 30, 2019
USD ($)
ft²
|
Jun. 30, 2019
USD ($)
|
Jun. 30, 2018
USD ($)
|
Jun. 30, 2019
USD ($)
|
Jun. 30, 2018
USD ($)
|
|
| Leases [Abstract] | |||||
| Lease expiration date | Aug. 31, 2021 | ||||
| Renewal term | 5 years | 5 years | |||
| Tenant improvement allowance | $ 646,000 | $ 646,000 | |||
| Sublease agreement date | 2019-04 | ||||
| Additional area rentable | ft² | 6,230 | ||||
| Sublease expiration date | 2021-02 | ||||
| Sublease amendment agreement date | 2019-04 | ||||
| Additional space sublease commencement date | Mar. 01, 2021 | ||||
| Base rent per month | $ 36,000 | ||||
| Weighted average remaining lease term | 2 years 1 month 6 days | 2 years 1 month 6 days | |||
| Operating lease liabilities, weighted average incremental borrowing rate | 7.00% | 7.00% | |||
| Operating lease, liabilities, current | $ 1,397,000 | $ 1,397,000 | |||
| Operating lease, liabilities, noncurrent | 1,600,000 | 1,600,000 | |||
| Rent expense for operating leases | 300,000 | $ 300,000 | 600,000 | $ 600,000 | |
| Variable lease payments for operating expenses | $ 100,000 | $ 100,000 | $ 300,000 | $ 200,000 | |
| X | ||||||||||
- Definition Additional Area Rentable for Sublease. No definition available.
|
| X | ||||||||||
- Definition Lessee operating sub lease base rent per month. No definition available.
|
| X | ||||||||||
- Definition Lessee Operating Sublease Agreement Date. No definition available.
|
| X | ||||||||||
- Definition Lessee Operating Sublease Amended Agreement Date No definition available.
|
| X | ||||||||||
- Definition Lessee Operating Sublease Commencement Date. No definition available.
|
| X | ||||||||||
- Definition Lessee Operating Sublease Expiration Date. No definition available.
|
| X | ||||||||||
- Definition Tenant improvement allowance. No definition available.
|
| X | ||||||||||
- Definition Date which lease or group of leases is set to expire, in CCYY-MM-DD format. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of operating lease expense. Excludes sublease income. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Weighted average discount rate for operating lease calculated at point in time. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of cash outflow for variable lease payment excluded from lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
Leases - Schedule of Undiscounted Future Non-Cancellable Lease Payments under Company's Operating Leases (Details) $ in Thousands |
Jun. 30, 2019
USD ($)
|
|---|---|
| Operating Leases | |
| Remaining 2019 | $ 777 |
| 2020 | 1,584 |
| 2021 | 864 |
| Total undiscounted lease payments | 3,225 |
| Present value adjustment for minimum lease commitments | (228) |
| Lease liabilities | $ 2,997 |
| X | ||||||||||
- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
Stockholders' Equity - Summary of Option Activity (Details) - 2015 and 2018 Stock Plan $ / shares in Units, $ in Thousands |
6 Months Ended | 12 Months Ended |
|---|---|---|
|
Jun. 30, 2019
USD ($)
$ / shares
shares
|
Dec. 31, 2018
USD ($)
$ / shares
shares
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Shares Issuable Under Options, Beginning balance | shares | 3,404,847 | |
| Shares Issuable Under Options, Options granted | shares | 186,652 | |
| Shares Issuable Under Options, Options exercised | shares | (308,516) | |
| Shares Issuable Under Options, Options forfeited | shares | (101,845) | |
| Shares Issuable Under Options, Ending balance | shares | 3,181,138 | 3,404,847 |
| Shares Issuable Under Options, Exercisable | shares | 2,071,836 | |
| Shares Issuable Under Options, Vested and expected to vest | shares | 3,181,138 | |
| Weighted-Average Exercise Price, Beginning balance | $ / shares | $ 6.55 | |
| Weighted-Average Exercise Price, Options granted | $ / shares | 14.57 | |
| Weighted-Average Exercise Price, Options exercised | $ / shares | 4.54 | |
| Weighted-Average Exercise Price, Options forfeited | $ / shares | 7.02 | |
| Weighted-Average Exercise Price, Ending balance | $ / shares | 7.20 | $ 6.55 |
| Weighted-Average Exercise Price, Exercisable | $ / shares | 6.46 | |
| Weighted-Average Exercise Price, Vested and expected to vest | $ / shares | $ 7.20 | |
| Weighted-Average Remaining Contract Term | 8 years 5 months 12 days | 8 years 9 months 25 days |
| Weighted-Average Remaining Contract Term Exercisable | 8 years 3 months 25 days | |
| Weighted-Average Remaining Contract Term Vested and expected to vest | 8 years 5 months 12 days | |
| Aggregate Intrinsic Value | $ | $ 12,331 | $ 31,388 |
| Aggregate Intrinsic Value Exercisable | $ | 8,906 | |
| Aggregate Intrinsic Value Vested and expected to vest | $ | $ 12,331 |
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Gross number of share options (or share units) granted during the period. No definition available.
|
| X | ||||||||||
- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
|
| X | ||||||||||
- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
|
| X | ||||||||||
- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
|
| X | ||||||||||
- Definition Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
Stockholders' Equity - Schedule of Total Stock-Based Compensation (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
| Total stock-based compensation | $ 1,125 | $ 616 | $ 2,229 | $ 1,047 |
| Research and Development | ||||
| Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
| Total stock-based compensation | 431 | 162 | 886 | 297 |
| General and Administrative | ||||
| Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
| Total stock-based compensation | $ 694 | $ 454 | $ 1,343 | $ 750 |
| X | ||||||||||
- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Stockholders' Equity - Additional Information (Details) - USD ($) |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Total stock-based compensation | $ 1,125,000 | $ 616,000 | $ 2,229,000 | $ 1,047,000 | |
| Total proceeds | $ 1,402,000 | $ 155,000 | |||
| Employee Share Purchase Plan (ESPP) | |||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Employee share purchase plan description | The initial offering period began June 27, 2018 and will end on August 15, 2020 with purchase dates of February 15, 2019, August 15, 2019, February 15, 2020, and August 15, 2020. Each subsequent offering will be approximately 24 months long and will consist of four purchase periods with purchase dates occurring on February 15 and August 15 of each year. On each purchase date, ESPP participants will purchase shares of common stock at a price per share equal to 85% of the lesser of (1) the fair market value per share of the common stock on the offering date or (2) the fair market value of the common stock on the purchase date. | ||||
| Employee share purchase plan purchase price percentage | 85.00% | 85.00% | |||
| Total stock-based compensation | $ 187,000 | $ 415,000 | |||
| Number of common stock purchase to ESPP | 44,656 | ||||
| Total proceeds | $ 588,000 | ||||
| Restricted Stock | Other Long-term Liabilities | |||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Shares held by employees and directors subject to repurchase | $ 18,000 | $ 18,000 | $ 144,000 | ||
| X | ||||||||||
- Definition Employee share purchase plan description. No definition available.
|
| X | ||||||||||
- Definition Employee share purchase plan purchase price percentage. No definition available.
|
| X | ||||||||||
- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition The number of shares purchased on the open market during the period for issuance to employees under the plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of stock repurchase plan authorized. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Stockholders' Equity - Summary of Restricted Stock Activity (Details) |
6 Months Ended |
|---|---|
|
Jun. 30, 2019
shares
| |
| Equity [Abstract] | |
| Number of Restricted Shares Outstanding, Beginning balance | 49,052 |
| Number of Restricted Shares Outstanding, Restricted shares vested | (33,999) |
| Number of Restricted Shares Outstanding, Ending balance | 15,053 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
Net Loss Per Share - Summary of Outstanding Potentially Dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (Details) - shares |
6 Months Ended | |
|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
| Total | 3,237,691 | 19,661,847 |
| Convertible Preferred Stock | ||
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
| Total | 16,215,896 | |
| Stock Options to Purchase Common Stock | ||
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
| Total | 3,181,138 | 3,374,318 |
| Restricted Stock | ||
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
| Total | 15,053 | 71,633 |
| Shares Committed under ESPP | ||
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
| Total | 41,500 | |
| X | ||||||||||
- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
Subsequent Events - Additional Information (Details) $ / shares in Units, ¥ in Billions |
1 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
|
Jul. 12, 2019
USD ($)
|
Jul. 31, 2019
USD ($)
$ / shares
shares
|
Jun. 30, 2019
USD ($)
|
Jun. 30, 2018
USD ($)
|
Jul. 10, 2019
USD ($)
|
Jul. 10, 2019
JPY (¥)
|
|
| Subsequent Event [Line Items] | ||||||
| Issuance of common stock | $ 588,000 | $ 0 | ||||
| Subsequent Event | License and Collaboration Agreement | Ono Pharmaceutical Co., Ltd. | ||||||
| Subsequent Event [Line Items] | ||||||
| One time upfront payment receivable | $ 15,700,000 | ¥ 1.7 | ||||
| Additional upfront payment receivable upon achievement of specified future development and commercial milestones | $ 103,300,000 | ¥ 11.2 | ||||
| Subsequent Event | Maximum | ||||||
| Subsequent Event [Line Items] | ||||||
| Securities available for issuance under shelf registration statement | $ 250,000,000 | |||||
| At-The-Market Offerings | Subsequent Event | Maximum | ||||||
| Subsequent Event [Line Items] | ||||||
| Issuance of common stock | $ 60,000,000 | |||||
| Underwritten Public Offering | Subsequent Event | ||||||
| Subsequent Event [Line Items] | ||||||
| Common stock shares, issued | shares | 10,781,250 | |||||
| Shares issued pursuant to exercise of underwriters' option to purchase | shares | 1,406,250 | |||||
| Common stock issued price per share | $ / shares | $ 8.00 | |||||
| Gross proceeds from offering | $ 86,300,000 | |||||
| X | ||||||||||
- Definition Additional upfront payment receivable upon achievement of specified future development and commercial milestones. No definition available.
|
| X | ||||||||||
- Definition Gross proceeds from offering. No definition available.
|
| X | ||||||||||
- Definition One time upfront payment receivable. No definition available.
|
| X | ||||||||||
- Definition Securities available for issuance, value, public offering. No definition available.
|
| X | ||||||||||
- Definition Underwriters' option to purchase additional shares. No definition available.
|
| X | ||||||||||
- Definition The cash inflow from the additional capital contribution to the entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction. No definition available.
|
| X | ||||||||||
- Definition Number of new stock issued during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. No definition available.
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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