Chinook Therapeutics (KDNY) 10-Q 30 Oct 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 26, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Trading Symbol	ADRO
Entity Registrant Name	ADURO BIOTECH, INC.
Entity Central Index Key	1,435,049
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		79,404,084

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 120,751	$ 157,614
Short-term marketable securities	145,043	168,489
Accounts receivable		989
Income tax receivable	17,841	17,495
Prepaid expenses and other current assets	4,128	5,544
Total current assets	287,763	350,131
Long-term marketable securities	12,840	23,614
Property and equipment, net	29,806	31,085
Goodwill	8,449	8,723
Intangible assets, net	29,698	31,107
Restricted cash	468	468
Total assets	369,024	445,128
Current liabilities:
Accounts payable	780	1,150
Accrued clinical trial and manufacturing expenses	3,760	5,898
Accrued expenses and other liabilities	8,601	12,601
Contingent consideration		6,829
Deferred revenue	17,744	14,923
Total current liabilities	30,885	41,401
Deferred rent	10,843	9,991
Contingent consideration	941	759
Deferred revenue	161,591	148,148
Deferred tax liabilities	6,237	6,538
Other long-term liabilities	832	818
Total liabilities	211,329	207,655
Commitments and contingencies (Note 7)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized; and no shares issued and outstanding at September 30, 2018 and December 31, 2017
Common stock, $0.0001 par value; 300,000,000 shares authorized; and 79,369,891 and 77,736,201 shares issued and outstanding at September 30, 2018 and December 31, 2017	8	8
Additional paid-in capital	534,632	519,435
Accumulated other comprehensive income	1,267	1,893
Accumulated deficit	(378,212)	(283,863)
Total stockholders’ equity	157,695	237,473
Total liabilities and stockholders’ equity	$ 369,024	$ 445,128

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Preferred stock par value per share	$ 0.0001	$ 0.0001
Preferred stock shares authorized	10,000,000	10,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Common stock par value per share	$ 0.0001	$ 0.0001
Common stock shares authorized	300,000,000	300,000,000
Common stock shares issued	79,369,891	77,736,201
Common stock shares outstanding	79,369,891	77,736,201

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue:
Total revenue	$ 3,063,000	$ 3,794,000	$ 12,329,000	$ 13,483,000
Operating expenses:
Research and development	18,675,000	24,454,000	58,223,000	66,464,000
General and administrative	9,149,000	8,458,000	27,021,000	24,982,000
Amortization of intangible assets	144,000	145,000	443,000	413,000
Total operating expenses	27,968,000	33,057,000	85,687,000	91,859,000
Loss from operations	(24,905,000)	(29,263,000)	(73,358,000)	(78,376,000)
Interest income	1,353,000	998,000	3,892,000	2,428,000
Other income (loss), net	21,000	(129,000)	(15,000)	(197,000)
Loss before income tax	(23,531,000)	(28,394,000)	(69,481,000)	(76,145,000)
Income tax benefit	385,000	3,874,000	444,000	10,414,000
Net loss	$ (23,146,000)	$ (24,520,000)	$ (69,037,000)	$ (65,731,000)
Net loss per common share, basic and diluted	$ (0.29)	$ (0.33)	$ (0.88)	$ (0.92)
Shares used in computing net loss per common share, basic and diluted	79,086,841	75,167,334	78,607,180	71,529,043
Collaboration and license revenue
Revenue:
Total revenue	$ 3,063,000	$ 3,704,000	$ 12,329,000	$ 13,352,000
Grant revenue
Revenue:
Total revenue		$ 90,000		$ 131,000

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (23,146)	$ (24,520)	$ (69,037)	$ (65,731)
Other comprehensive income (loss):
Unrealized gain on marketable securities	111	37	16	38
Foreign currency translation adjustments	(24)	1,056	(642)	3,347
Comprehensive loss	$ (23,059)	$ (23,427)	$ (69,663)	$ (62,346)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows from Operating Activities
Net loss	$ (69,037)	$ (65,731)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,268	2,547
Amortization of intangible assets	443	413
Accretion of discounts and amortization of premiums on marketable securities	(800)	544
Stock-based compensation	13,472	12,010
Loss from remeasurement of fair value of contingent consideration	570	1,622
Loss on disposal of property and equipment	3	5
Deferred income tax	(99)	2,037
Changes in operating assets and liabilities:
Payment of contingent consideration	(3,322)
Accounts receivable	989	(210)
Income tax receivable	(346)	(12,509)
Prepaid expenses and other assets	1,631	1,668
Accounts payable	(26)	(863)
Deferred revenue	(9,246)	(11,218)
Accrued clinical trial and manufacturing expenses	(2,076)	1,581
Accrued expenses and other liabilities	(3,090)	3,544
Net cash used in operating activities	(67,666)	(64,560)
Cash Flows from Investing Activities
Purchase of marketable securities	(179,277)	(241,397)
Proceeds from maturities of marketable securities	214,314	313,398
Purchase of property and equipment	(2,007)	(3,382)
Proceeds from sale of property and equipment	10
Net cash provided by investing activities	33,040	68,619
Cash Flows from Financing Activities
Payment of contingent consideration	(3,481)
Proceeds from the issuance of common stock, net of issuance costs		77,156
Proceeds from employee stock purchase plan	366	494
Proceeds from exercise of stock options and warrants	1,328	1,864
Net cash provided by financing activities	(1,787)	79,514
Effect of exchange rate changes	(450)	535
Net (decrease) increase in cash, cash equivalents, and restricted cash	(36,863)	84,108
Cash, cash equivalents, and restricted cash at beginning of period	158,082	75,400
Cash, cash equivalents, and restricted cash at end of period	121,219	159,508
Supplemental Disclosure of Cash Flow Information
Cash paid for taxes		850
Supplemental Disclosure of Non-Cash Investing and Financing Activities
Purchase of property and equipment in accounts payable and accrued liabilities	363	896
Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents	120,751	159,040
Restricted cash	468	468
Cash, cash equivalents, and restricted cash at end of period	$ 121,219	$ 159,508

Organization and Nature of Busi

Organization and Nature of Business	9 Months Ended
	Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Nature of Business	1. Organization and Nature of Business Aduro Biotech, Inc., and its wholly owned subsidiaries, or Aduro, or the Company, is an immunotherapy company focused on the discovery, development and commercialization of therapies that are intended to transform the treatment of challenging diseases. Aduro's technologies, which are designed to harness the body's natural immune system, are being investigated in cancer indications, autoimmune diseases and have the potential to expand into infectious diseases. The Company is located in Berkeley, California and its wholly-owned subsidiary, Aduro Biotech Holdings, Europe B.V., or Aduro Biotech Europe, is based in the Netherlands. The Company operates in one business segment. Aduro's STING pathway activator technology is designed to activate the STING receptor in immune cells, which may result in a potent tumor-specific immune response. ADU-S100 (MIW815) is the first STING compound to enter the clinic and is currently being evaluated in a Phase 1 clinical trial as a single agent and in combination with ipilimumab and in a Phase 1b combination trial with spartalizumab (PDR001), an investigational anti-PD1 immune checkpoint inhibitor. Aduro’s B-select monoclonal antibody technology, including BION-1301, an anti-APRIL antibody, is comprised of a number of immune modulating assets in research and development. Aduro is collaborating with leading global pharmaceutical companies to expand its products and technologies.

Basis of Presentation, Use of E

Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements	2. Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP, and follow the requirements of the Securities and Exchange Commission, or the SEC, for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2017 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements. These financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair presentation of the Company’s financial information. The results of operations for the three and nine months ended September 30, 2018 are not necessarily indicative of the results to be expected for the year ending December 31, 2018 or for any other interim period or for any other future year. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto for the year ended December 31, 2017 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 filed with the SEC on March 1, 2018. The consolidated financial statements include the accounts of Aduro Biotech, Inc. and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities and reported amounts of revenue and expenses in the financial statements and accompanying notes. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, clinical trial accruals, contingent consideration, income taxes and stock-based compensation. Management bases its estimates on historical experience and on various other market-specific and relevant assumptions that management believes to be reasonable under the circumstances. Actual results could differ from these estimates. Revenue Recognition The Company recognizes revenue when its customers obtain control of the promised goods or services, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods or services. Collaboration and license revenue The Company’s collaboration agreements may include the transfer of intellectual property rights in the form of licenses, obligations to provide research and development services and obligations to participate on certain development committees with the collaboration party. The terms of such agreements include payment to the Company of one or more of the following: nonrefundable upfront fees, payment for research and development services, development, regulatory and commercial milestone payments, and royalties on net sales of licensed products. The Company assesses whether the promises in these agreements are considered distinct performance obligations that should be accounted for separately. Judgment is required to determine whether the license to the Company’s intellectual property is distinct from the research and development services or participation on development committees. The transaction price in each agreement is allocated to the identified performance obligations based on the standalone selling price, or SSP, of each distinct performance obligation. Judgment is required to determine SSP. In instances where SSP is not directly observable, such as when a license or service is not sold separately, SSP is determined using information that may include market conditions and other observable inputs. Due to the early stage of the Company’s licensed technology, the license of such technology is typically combined with the research and development services and committee participation as one performance obligation. Revenue associated with nonrefundable upfront license fees where the license fees and research and development services cannot be accounted for as separate performance obligations is deferred and recognized as revenue over the expected period of performance using a cost-based input methodology. The Company utilizes judgment to assess the pattern of delivery of the performance obligation. At the inception of each agreement that includes development, regulatory or commercial milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price by using the most likely amount method. If it is probable that a significant reversal of cumulative revenue would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received or the underlying activity has been completed. The transaction price is then allocated to each performance obligation in the agreement based on relative SSP. At the end of each subsequent reporting period, the Company re-evaluates the probability of achievement of each such milestone and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. Contract Balances Upfront payments and fees are recorded as deferred revenue upon receipt or when due, and may require deferral of revenue recognition to a future period until the Company performs its obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional. Recent Accounting Pronouncements In February 2016, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2016-02, Leases (Topic 842), which establishes a comprehensive new lease accounting model. The new standard: (a) clarifies the definition of a lease; (b) requires a dual approach to lease classification similar to current lease classifications; and (c) causes lessees to recognize leases on the balance sheet as a lease liability with a corresponding right-of-use asset for leases with a lease-term of more than twelve months. The new standard is effective for fiscal years and interim periods beginning after December 15, 2018, with early adoption permitted. A modified retrospective transition approach is required for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, including a number of optional practical expedients that entities may elect to apply. In July 2018, the FASB issued ASU No. 2018-11, Leases (Topic 842): Targeted Improvements, an update which provides another transition method, in addition to the existing modified retrospective transition method, by allowing entities to initially apply the new lease standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. In preparation for adoption of the standard, the Company engaged a third-party service provider to assist the Company with the evaluation. The Company has identified all leases and is currently reviewing the leases to determine the impact of the update on the Company’s consolidated financial statements. The Company is planning to adopt the new standard by initially applying the guidance at the adoption date, January 1, 2019, and recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption as permitted by ASU No. 2018-11. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326). The standard changes how entities will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. Financial assets measured at amortized cost will be presented at the net amount expected to be collected by using an allowance for credit losses. The standard is effective for fiscal years and interim periods beginning after December 15, 2019. Early adoption is permitted for all periods beginning after December 15, 2018. The Company has evaluated the impact of this guidance and has concluded that adoption of the standard will not have a material impact on its consolidated financial statements. In February 2018, the FASB issued ASU No. 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220). The standard update allows for a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act of 2017, or the Tax Act. Consequently, the ASU 2018-02 eliminates the stranded tax effects resulting from the Tax Act. The new standard is effective for fiscal years and interim periods beginning after December 15, 2018. Early adoption is permitted, including adoption in any interim period for reporting periods for which financial statements have not yet been issued. The new standard should be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Act is recognized. The Company has evaluated the impact of this guidance and has concluded that adoption of the standard will not have a material impact on its consolidated financial statements. In June 2018, the FASB issued ASU No. 2018-07 – Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Shared-Based Payment Accounting. The standard update expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The new standard simplifies several aspects of Topic 718 by expanding the scope of the following areas to account for nonemployee shared-based payment transactions: (1) overall measurement objective, (2) measurement date, (3) awards with performance conditions, and (4) classification reassessment of certain equity-classified awards. The new standard is effective for fiscal years and interim periods beginning after December 15, 2018. Early adoption is permitted, but no earlier than an entity’s adoption date of Topic 606. The Company has evaluated the impact of this guidance and has concluded that adoption of the standard will not have a material impact on its consolidated financial statements. Recently Adopted Accounting Pronouncements In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments--Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which amends the guidance in U.S. GAAP on the classification and measurement of financial instruments. In February 2018, the FASB issued ASU No. 2018-03 which provides additional clarification and implementation guidance on the previously issued ASU No. 2016-01. Changes to the current guidance primarily affect the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. In addition, the ASU clarifies guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on available-for-sale debt securities. The new standard is effective for fiscal years and interim periods beginning after December 15, 2017, and upon adoption, an entity should apply the amendments by means of a cumulative-effect adjustment to the balance sheet at the beginning of the first reporting period in which the guidance is effective. The Company adopted this ASU on January 1, 2018. The adoption of the standard did not have a material impact on its condensed consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). This ASU as well as its related amendments affect any entity that either enters into contracts with customers to transfer goods and services or enters into contracts for the transfer of nonfinancial assets. ASU 2014-09 replaced most existing revenue recognition guidance in U.S. GAAP when it became effective. The standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which it expects to be entitled in exchange for those goods or services. The Company adopted this standard on January 1, 2018 using the modified retrospective method. The Company recognized the cumulative effect of initially applying the new revenue standard as an adjustment to the opening balance of its accumulated deficit. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. As a result, the Company changed its accounting policy for revenue recognition, and the details of the significant changes and quantitative impact of the changes are disclosed below. Milestone payments – under the milestone method ASC 605-28, payments that were contingent upon the achievement of a substantive milestone were recognized entirely as revenue in the period in which the milestone was achieved. To the extent that non-substantive milestones were achieved and the Company had remaining performance obligations, milestones were deferred and recognized as revenue over the estimated remaining period of performance. If there were no remaining performance obligations, the revenue from non-substantive milestones was recognized in the period it was earned. The milestone method no longer exists under the new revenue standard. The revenue from the milestone payments must be estimated using either the expected value method or the most likely amount method. Revenue that is not probable of significant reversal of cumulative revenue is included in the transaction price. Therefore, substantive milestones that were recognized when achieved under the legacy revenue guidance will be recognized as revenue over the performance period under the new standard with a cumulative catch-up recorded for the portion associated with the performance to date. Pattern of revenue recognition – the Company recognized revenue from performance obligations delivered over time, such as licenses combined with research and development services and participation on development committees, on a straight-line basis over the period of performance under the legacy revenue guidance. The new standard allows entities to use either an input method or an output method to measure progress toward complete satisfaction of a performance obligation. For contracts in progress at the adoption date of the new standard the Company determined that the input method of measuring costs incurred to date compared to total estimated costs to be incurred under the contract most accurately depicts its performance. The change in the pattern of revenue recognition upon adoption of Topic 606 for milestone payments and performance obligations delivered over time resulted in an increase in the balance of deferred revenue and an increase in the accumulated deficit balance of $25.3 million on January 1, 2018. The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated balance sheet line items (in thousands): September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) Liabilities Deferred revenue $ 17,744 $ (2,929 ) $ 14,815 Deferred revenue – noncurrent 161,591 (24,554 ) 137,037 Stockholders’ Equity Accumulated deficit (378,212 ) 27,483 (350,729 ) The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated statement of operations line items (in thousands, except per share data): Three Months Ended September 30, 2018 Nine Months Ended September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) (in thousands) Collaboration and license revenue $ 3,063 $ 866 $ 3,929 $ 12,329 $ 2,171 $ 14,500 Total revenue 3,063 866 3,929 12,329 2,171 14,500 Loss from operations (24,905 ) 866 (24,039 ) (73,358 ) 2,171 (71,187 ) Net loss (23,146 ) 866 (22,280 ) (69,037 ) 2,171 (66,866 ) Net loss per share, basic and diluted (0.29 ) 0.01 (0.28 ) (0.88 ) 0.03 (0.85 ) The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated statement of cash flows line items (in thousands): Nine Months Ended September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) Cash flows from operating activities Net loss $ (69,037 ) $ 2,171 $ (66,866 ) Changes in operating assets and liabilities: Deferred revenue (9,246 ) (2,171 ) (11,417 ) In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 identifies how certain cash receipts and cash payments are presented and classified in the Statement of Cash Flows. The standard is effective for fiscal years and interim periods beginning after December 15, 2017. The standard should be applied retrospectively, and early adoption is permitted, including adoption in an interim period. The Company adopted this standard on January 1, 2018 and the adoption of the standard did not have a material impact on its condensed consolidated statement of cash flows. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. ASU 2016-18 requires that the statement of cash flows explain the change during the period in the total cash, cash equivalents, and restricted cash. The standard is effective for fiscal years beginning after December 15, 2017, and interim periods within those years. This standard should be applied retrospectively and early adoption is permitted, including adoption in an interim period. The Company adopted this standard on January 1, 2018 utilizing the required retrospective transition method and changed the presentation and classification of restricted cash in its condensed consolidated statement of cash flows. In May 2017, the FASB issued ASU No. 2017-09, Compensation – Stock Compensation (Topic 718): Scope of Modification Accounting. ASU 2017-09 provides clarity and reduces the complexity of applying the guidance in Topic 718, Compensation – Stock Compensation, to a change to the terms or conditions of a share-based payment award. This standard is effective for annual periods beginning after December 15, 2017. The Company adopted this ASU on January 1, 2018, and the In March 2018, the FASB issued ASU No. 2018-05, Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118, which included amendments to expand income tax accounting and disclosure guidance pursuant to SEC Staff Accounting Bulletin No. 118 (“SAB 118”) issued by the SEC in December 2017. SAB 118 provides guidance on accounting for the income tax effects of the Tax Act. The Company adopted this ASU in the first quarter of 2018. Refer to Note 10 Income Taxes for more information and disclosures related to this amended guidance.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The carrying amounts of certain of the Company’s financial instruments, including cash equivalents, accounts receivable and accounts payable, approximate their fair values due to their short maturities. Assets and liabilities recorded at fair value on a recurring basis in the balance sheets, as well as assets and liabilities measured at fair value on a non-recurring basis or disclosed at fair value, are categorized based upon the level of judgment associated with inputs used to measure their fair values. The accounting guidance for fair value provides a framework for measuring fair value and requires certain disclosures about how fair value is determined. Fair value is defined as the price that would be received upon the sale of an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. The accounting guidance also establishes a three-level valuation hierarchy that prioritizes the inputs to valuation techniques used to measure fair value based upon whether such inputs are observable or unobservable. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect market assumptions made by the reporting entity. The three-level hierarchy for the inputs to valuation techniques is briefly summarized as follows: Level 1 —Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2 —Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and Level 3 —Unobservable inputs that are significant to the measurement of the fair value of the assets or liabilities that are supported by little or no market data. The Company’s cash equivalents, which include money market funds, are classified as Level 1 because they are valued using quoted market prices. The Company’s marketable securities consist of available-for-sale securities and are generally classified as Level 2 because their value is based on valuations using significant inputs derived from or corroborated by observable market data. In certain cases where there is limited activity or less transparency around the inputs to valuation, financial instruments are classified as Level 3. Level 3 liabilities consist of the contingent consideration liability. The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): September 30, 2018 Level 1 Level 2 Level 3 Total Financial Assets: Money market funds $ 28,243 $ — $ — $ 28,243 U.S. government and agency securities — 73,492 — 73,492 Corporate debt securities — 66,244 — 66,244 Commercial paper — 89,587 — 89,587 Total $ 28,243 $ 229,323 $ — $ 257,566 Financial Liabilities: Contingent consideration related to acquisition $ — $ — $ 941 $ 941 Total $ — $ — $ 941 $ 941 December 31, 2017 Level 1 Level 2 Level 3 Total Financial Assets: Money market funds $ 86,461 $ — $ — $ 86,461 U.S. government and agency securities — 108,076 — 108,076 Corporate debt securities — 58,496 — 58,496 Commercial paper — 74,011 — 74,011 Total $ 86,461 $ 240,583 $ — $ 327,044 Financial Liabilities: Contingent consideration related to acquisition $ — $ — $ 7,588 $ 7,588 Total $ — $ — $ 7,588 $ 7,588 The fair value of the contingent consideration liability represents the future consideration that is contingent upon the achievement of specified development milestones for a product candidate. The fair value of the contingent consideration is based on the Company’s probability-weighted discounted cash flow assessment that considers probability and timing of future payments. The fair value measurement is based on significant Level 3 inputs such as anticipated timelines and probability of achieving development milestones. Changes in the fair value of the liability for contingent consideration, except for the impact of foreign currency, will be recognized as research and development expense in the condensed consolidated statements of operations until settlement. In the third quarter of 2018, the Company received regulatory authorization to conduct clinical studies for a specified antibody product candidate, which triggered payment of contingent consideration. A total of $6.8 million was paid to the former shareholders of BioNovion Holding B.V., BioNovion, under the terms of the 2015 share sale agreement pursuant to which the Company acquired BioNovion. The Company did not have any financial assets and liabilities measured at fair value on a non-recurring basis as of September 30, 2018 and December 31, 2017. There were no transfers between the fair value measurement category levels during any of the periods presented. The following table sets forth a summary of the changes in the fair value of the Company’s Level 3 financial liabilities (in thousands): Contingent Consideration Balance at December 31, 2017 $ 7,588 Net change in fair value upon remeasurement 574 Payment of contingent considerations (6,803 ) Foreign currency impact on contingent consideration (418 ) Balance at September 30, 2018 $ 941 The following tables summarize the estimated value of the Company’s cash, cash equivalents and marketable securities and the gross unrealized holding gains and losses (in thousands): September 30, 2018 Amortized cost Unrealized gains Unrealized losses Estimated Fair Value Cash and cash equivalents: Cash $ 21,068 $ — $ — $ 21,068 Money market funds 28,243 — — 28,243 Commercial paper 70,840 — — 70,840 U.S. government and agency securities 600 — — 600 Total cash and cash equivalents $ 120,751 $ — $ — $ 120,751 Marketable securities: U.S. government and agency securities $ 73,138 $ — $ (246 ) $ 72,892 Corporate debt securities 66,278 1 (35 ) 66,244 Commercial paper 18,747 — — 18,747 Total marketable securities $ 158,163 $ 1 $ (281 ) $ 157,883 December 31, 2017 Amortized cost Unrealized gains Unrealized losses Estimated Fair Value Cash and cash equivalents: Cash $ 22,673 $ — $ — $ 22,673 Money market funds 86,461 — — 86,461 Commercial paper 48,480 — — 48,480 Total cash and cash equivalents $ 157,614 $ — $ — $ 157,614 Marketable securities: U.S. government and agency securities $ 108,317 $ — $ (241 ) $ 108,076 Corporate debt securities 58,551 1 (56 ) 58,496 Commercial paper 25,531 — — 25,531 Total marketable securities $ 192,399 $ 1 $ (297 ) $ 192,103 The amortized cost and estimated fair value of the Company’s available-for-sale marketable securities by contractual maturity are summarized below as of September 30, 2018 (in thousands): Amortized cost Estimated Fair Mature in one year or less $ 145,279 $ 145,043 Mature after one year through two years 12,884 12,840 Total available-for-sale marketable securities $ 158,163 $ 157,883

Balance Sheet Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2018
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Components	4. Balance Sheet Components Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): September 30, December 31, 2018 2017 Leasehold improvements $ 26,964 $ 27,102 Lab equipment 8,081 7,243 Computer and office equipment 2,171 2,016 Furniture 1,750 1,767 Construction in progress 1,304 54 Total property and equipment 40,270 38,182 Less: accumulated depreciation (10,464 ) (7,097 ) Property and equipment, net $ 29,806 $ 31,085 Depreciation expense was $1.1 million and $888,000 for the three months ended September 30, 2018 and 2017, respectively, and $3.3 million and $2.5 million for the nine months ended September 30, 2018 and 2017, respectively. Accrued Expenses and Other Liabilities Accrued expenses and other liabilities consisted of the following (in thousands): September 30, December 31, 2018 2017 Compensation and related benefits $ 3,782 $ 5,320 Professional and consulting services 1,864 1,586 Accrued research expense 833 1,763 Deferred rent 627 434 Accrued property and equipment 309 2,790 Other 1,186 708 Total accrued expenses and other liabilities $ 8,601 $ 12,601

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	5. Goodwill and Intangible Assets Goodwill The gross carrying amount of goodwill was as follows (in thousands): Balance at December 31, 2017 $ 8,723 Foreign currency translation adjustment (274 ) Balance at September 30, 2018 $ 8,449 Intangible assets The gross carrying amounts and net book value of intangible assets were as follows (in thousands): September 30, 2018 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: License agreement $ 11,474 $ 1,673 $ 9,801 Total intangible assets with finite lives 11,474 1,673 9,801 Acquired IPR&D assets 19,897 — 19,897 Total intangible assets $ 31,371 $ 1,673 $ 29,698 December 31, 2017 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: License agreement $ 11,847 $ 1,283 $ 10,564 Total intangible assets with finite lives 11,847 1,283 10,564 Acquired IPR&D assets 20,543 — 20,543 Total intangible assets $ 32,390 $ 1,283 $ 31,107 Intangible assets are carried at cost less accumulated amortization. The license agreement is being amortized over a period of 20 years and the amortization expense is recorded in operating expenses. The decrease in the gross carrying amount of intangible assets as of September 30, 2018 compared to December 31, 2017 reflects the impact of foreign currency exchange. Amortization expense was $144,000 and $145,000 for the three months ended September 30, 2018 and 2017, respectively, and $443,000 and $413,000 for the nine months ended September 30, 2018 and 2017, respectively. Based on finite-lived intangible assets recorded as of September 30, 2018, the estimated future amortization expense is as follows (in thousands): Year Ending December 31, Estimated Amortization Expense 2018 (remaining three months) $ 143 2019 574 2020 574 2021 574 2022 574 2023 574

Collaboration Agreements

Collaboration Agreements	9 Months Ended
	Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaboration Agreements	6. Collaboration Agreements Novartis Agreement In March 2015, the Company entered into a collaboration and license agreement with Novartis Pharmaceuticals Corporation, or Novartis, pursuant to which the Company is collaborating worldwide with Novartis regarding the development and potential commercialization of product candidates containing an agonist of the molecular target known as STING in the field of oncology, including immuno-oncology and cancer vaccines. Under this agreement, or the Novartis Agreement, the Company granted Novartis a co-exclusive license to develop such products worldwide, an exclusive license to commercialize such products outside the United States and a non-exclusive license to support the Company in commercializing such products in the United States if it requests such support. The collaboration is guided by a joint steering committee with each party having final decision-making authority regarding specified areas of development or commercialization. Under the Novartis Agreement, the Company received an upfront payment of $200.0 million in April 2015. During the second quarter of 2016, the Company received a $35.0 million development milestone upon initiation of a Phase 1 trial for the first STING product candidate, ADU-S100. The Company also received reimbursement of research and development costs from Novartis of $1.3 million since inception through September 30, 2018. The Company is eligible to receive up to an additional $215.0 million in development milestones and up to an additional $250.0 million in regulatory approval milestones. The Company is responsible for 38% of the joint development costs worldwide, and Novartis is responsible for the remaining 62% of the joint development costs worldwide. The Company will receive 50% of gross profits on sales of any products commercialized pursuant to this collaboration in the United States and 45% of gross profits for specified European countries and Japan. For each of these profit share countries, each party will be responsible for its respective commercial sharing percentage of all joint commercialization costs incurred in that country. For all other countries where the Company is not sharing profits, Novartis will be responsible for all commercialization costs and will pay the Company a royalty in the mid-teens on all net sales of product sold by Novartis, its affiliates and sublicensees, with such percentage subject to reduction post patent and data exclusivity expiration and subject to reduction, capped at a specified percentage, for royalties payable to third party licensors. Novartis’ royalty obligation will run on a country-by-country basis until the later of expiration of the last valid claim covering the product, expiration of data exclusivity for the product or 12 years after first commercial sale of the product in such country. With respect to the United States, specified European countries and/or Japan, the Company may elect for such region to either reduce by 50% or to eliminate in full the Company’s development and commercialization cost sharing obligation. If the Company elects to reduce its cost sharing percentage by 50% in any such region, then its profit share in such region will also be reduced by 50%. If the Company elects to eliminate its development cost sharing obligation, then such region will be removed from the profit share, and instead Novartis will owe the Company royalties on any net sales of product for such region, as described above. The Company has determined that the license is not distinct from the co-development services to be performed under the agreement, consisting of research and development services and regulatory filing services. Specifically, the Company’s development license and the manufacturing license can only provide benefit to Novartis in combination with the Company’s research and development services. The intellectual property related to STING agonists, proprietary to the Company, is the foundation for the research and development activities, and can only be utilized via engaging the Company’s team in the research. Hence, the research and development services provided by the Company significantly affect the development and manufacturing license’s utility to Novartis. The Company determined that the regulatory filing services of collaboration products are interrelated with research and development services, as the scope and timing of the regulatory filings will depend upon successful clinical outcomes. Therefore, the research and development services are the input of the regulatory services and thus are combined as one performance obligation with the license. For revenue recognition purposes, the Company determined that the duration of the contract begins on the effective date in March 2015 and ends upon receipt of regulatory approval, estimated to occur in 2028. The Company’s performance period commenced in May 2015. The transaction price consists of the $200.0 million upfront fee, a $35.0 million milestone payment received in the second quarter of 2016 upon commencement of a Phase 1 study, and $1.3 million in reimbursement of research and development costs through September 30, 2018. The Company determined that the remaining potential milestone payments are probable of significant reversal of cumulative revenue as their achievement is highly dependent on the successful completion of Phase 1 studies. Therefore, these payments are not included in the transaction price. Any consideration related to sales-based royalties and profit-sharing payments will be recognized when the related sales occur as they were determined to relate predominantly to the license granted to Novartis and have been excluded from the transaction price. The transaction price of $236.3 million is allocated to one combined performance obligation. The Company will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. The Company concluded that it will utilize a cost-based input method to measure its progress toward completion of its performance obligation and to calculate the corresponding amount of revenue to recognize each period. The Company believes this is the best measure of progress because other measures do not reflect how the Company transfers its performance obligation to Novartis. In applying the cost-based input method of revenue recognition, the Company uses actual clinical study enrollment figures as well as actual costs incurred relative to budgeted costs expected to be incurred for the combined performance obligation. These costs consist primarily of internal full-time equivalent effort and third-party contract costs relative to the level of patient enrollment in the study. Revenue will be recognized based on the level of costs incurred relative to the total budgeted costs for the performance obligations. A cost-based input method of revenue recognition requires management to make estimates of costs to complete the Company's performance obligation. In making such estimates, significant judgment is required to evaluate assumptions related to cost estimates. The cumulative effect of revisions to estimated costs to complete the Company's performance obligation will be recorded in the period in which changes are identified and amounts can be reasonably estimated. A significant change in these assumptions and estimates could have a material impact on the timing and amount of revenue recognized in future periods. Cost-sharing payments from Novartis are included in the transaction price and subject to the cost-based input method to determine the amount to be recognized in license and collaboration revenue in the Company’s condensed consolidated statements of operations, while cost-sharing payments to Novartis are accounted for as research and development expenses in the Company’s condensed consolidated statements of operations. If the Company recognizes revenue from the sale of any products commercialized pursuant to this collaboration in the United States, it will retain 50% of the gross profits from such sales, and will pay the remaining 50% of the gross profits to Novartis. The Company will receive from Novartis 45% of gross profits for specified European countries and Japan from the sale of any products commercialized pursuant to this collaboration in such countries. Profit sharing payments made to or received from Novartis will be aggregated by product by territory and reported as expenses or revenues, as applicable. For the three months ended September 30, 2018 and 2017, the Company recognized $3.0 million and $3.7 million, respectively, and for the nine months ended September 30, 2018 and 2017, the Company recognized $9.1 million and $11.2 million, respectively, in revenue from its collaboration with Novartis. The remaining balance of the transaction price of $179.3 million is included in deferred revenue at September 30, 2018. Janssen ADU-214 Agreement In October 2014, the Company entered into a Research and License Agreement, or the Janssen ADU-214 Agreement, with Janssen Biotech Inc., or Janssen, a wholly owned subsidiary of Johnson & Johnson Development Corporation, to develop a drug for the treatment of lung cancer. On September 25, 2018, the Company received written notice of termination for the Janssen ADU-214 Agreement, effective December 24, 2018. Under the terms of the Janssen ADU-214 Agreement, the Company granted Janssen an exclusive, worldwide license to research, develop, manufacture, use, sell and otherwise exploit products containing ADU-214 for any and all uses. The Company was responsible for certain research and development activities from the effective date of the agreement until investigational new drug application, or IND, approval which occurred in the fourth quarter of 2015. The Company recognized an upfront license fee of $30.0 million on a straight-line basis from the effective date of the agreement through October 2015 and milestone payments of $21.0 million in 2015 as all performance obligations were achieved. Janssen ADU-741 and GVAX Prostate Agreements In May 2014, the Company entered into a Research and License Agreement, or the Janssen ADU-741 Agreement, and a GVAX Prostate License Agreement, or Janssen GVAX Prostate Agreement, with Janssen to collaborate on the development of a drug for the treatment of prostate cancer. On September 25, 2018, the Company received written notices of termination for the Janssen ADU-741 and GVAX Prostate License Agreements, effective December 24, 2018. Under the terms of the Janssen ADU-741 Agreement and the GVAX Prostate License Agreement, the Company granted Janssen exclusive, worldwide licenses to research, develop, manufacture, use, sell and otherwise exploit products containing ADU-741 and GVAX Prostate, respectively, for any and all uses. The Company was responsible for certain research and development activities from the effective date of the Janssen ADU-741 Agreement until IND approval which occurred in the fourth quarter of 2015. The Company recognized upfront fees totaling $12.5 million on a straight-line basis from the effective date of the agreements through October 2015 and milestone payments of $10.0 million in 2015 as all performance obligations were achieved. Merck License Agreement In connection with the acquisition of Aduro Biotech Europe in October 2015, the Company became party to an agreement with Merck Sharp & Dohme Corp., or Merck. The agreement sets forth the parties’ respective obligations for development, commercialization, regulatory and manufacturing and supply activities for antibody product candidates. The Company identified the following promises under the agreement: 1) the license, 2) the obligation to provide research activities and 3) the obligation to participate on a Joint Research Committee. The Company determined that the promises were not distinct which resulted in them being combined into one performance obligation. The Company completed its performance obligation under the agreement by the end of 2016. The Company received a milestone payment of $2.0 million in 2017 for the initiation of a GLP toxicology study, which was recognized in revenue when received as the Company had no remaining performance obligation. The Company also received a milestone payment of $3.0 million in the first quarter of 2018 for the initiation of a Phase 1 trial for the anti-CD27 antibody

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. Commitments and Contingencies Leases The Company moved into its corporate office and laboratory facility located in Berkeley, California in August 2016. The Company leases approximately 110,853 square feet pursuant to an office/laboratory lease that was entered into in September 2015, or the Heinz Lease. The Heinz Lease has an initial term of approximately thirteen and a half years expiring on December 31, 2029. The Company has the right to further extend the Heinz Lease term for up to two renewal terms of five years each, provided that the rental rate would be subject to market adjustment at the beginning of each renewal term. The Company is subleasing approximately 30,100 square feet in its Heinz facility under subleases that expire on or before December 31, 2020. The Company continues to lease its former office and research and development facility comprised of 25,000 square feet in Berkeley, California, under a non-cancelable operating lease, or the Bancroft Lease. The term of the Bancroft Lease expires on December 31, 2018. The Company has transitioned the entirety of its Berkeley operations to its Heinz facility and in accordance with the terms of the Bancroft Lease, the Company has subleased the Bancroft facility. The Company maintains a letter of credit with Bank of America Merrill Lynch as security for the Heinz Lease in the amount of $468,000. The letter of credit is collateralized by a certificate of deposit for $468,000 which has been included in restricted cash in the condensed consolidated balance sheets as of September 30, 2018 and December 31, 2017. The Company also leases a research and development facility in Oss, the Netherlands, for employees of Aduro Biotech Europe. The term of the Oss lease has been extended through December 2020. The Company believes that its existing facilities are adequate to meet its current needs, and that suitable additional alternative spaces will be available in the future on commercially reasonable terms. Rent expense was $1.4 million and $1.2 million for the three months ended September 30, 2018 and 2017, respectively, and $4.3 million and $4.1 million for the nine months ended September 30, 2018 and 2017, respectively. Under the terms of the lease agreements, the Company is also responsible for certain insurance, property tax and maintenance expenses. Future minimum payments under the leases at September 30, 2018 are as follows (in thousands): Year Ending December 31, Amounts 2018 (remaining three months) $ 1,500 2019 5,525 2020 5,676 2021 5,332 2022 5,460 Thereafter 41,406 Total $ 64,899 Indemnification In the ordinary course of business, the Company enters into agreements that may include indemnification provisions. Pursuant to such agreements, the Company may indemnify, hold harmless and defend an indemnified party for losses suffered or incurred by the indemnified party. Some of the provisions will limit losses to those arising from third party actions. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments the Company could be required to make under these provisions is not determinable. The Company has never incurred material costs to defend lawsuits or settle claims related to these indemnification provisions. The Company has also entered into indemnification agreements with its directors and officers that may require the Company to indemnify its directors and officers against liabilities that may arise by reason of their status or service as directors or officers to the fullest extent permitted by Delaware corporate law. The Company currently has directors’ and officers’ insurance. Legal The Company is not party to any material legal proceedings at this time. From time to time, the Company may become involved in various legal proceedings that arise in the ordinary course of its business. Other Commitments The Company has various manufacturing, clinical, research and other contracts with vendors in the conduct of the normal course of its business. All contracts are terminable, with varying provisions regarding termination. If a contract with a specific vendor were to be terminated, generally the Company would only be obligated for the products or services that the Company had received at the time the termination became effective as well as non-cancelable and non-refundable obligations, including those incurred by the vendor for products or services before the termination became effective, and in some cases a termination fee. In the case of terminating a clinical trial agreement at a particular site, the Company may also be obligated to provide continued support for appropriate treatment for clinical trial subjects at that site until or after completion or termination.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Stockholders' Equity	8. Stockholders’ Equity At-the-Market Sales Agreement In August 2017, the Company entered into an “at-the-market” sales agreement, or the 2017 Sales Agreement, with Cowen and Company, LLC, or Cowen In May 2016, the Company entered into an “at-the-market” sales agreement, or the 2016 Sales Agreement, with Cowen, through which the Company offered and sold 8,350,018 shares of its common stock for total net proceeds of $97.3 million from May 2016 through the second quarter of 2017 through Under the 2016 Sales Agreement, the Company agreed to pay Cowen a commission of up to 3% of the gross proceeds of any sales made pursuant to the Sales Agreement. There are no amounts remaining for future sales under the 2016 Sales Agreement.

Equity Incentive Plans

Equity Incentive Plans	9 Months Ended
	Sep. 30, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity Incentive Plans	9. Equity Incentive Plans 2015 Plan In March 2015, the Company’s board of directors adopted and in April 2015 the Company’s stockholders approved the 2015 Equity Incentive Plan, or the 2015 Plan, which became effective upon the initial public offering of the Company’s common stock, or IPO, and provides for the granting of incentive stock options, nonstatutory stock options and other forms of stock awards to its employees, directors and consultants. The Company’s 2009 Stock Incentive Plan, or the 2009 Plan, terminated on the date the 2015 Plan was adopted. Options granted or shares issued under the 2009 Plan that were outstanding on the date the 2015 Plan became effective will remain subject to the terms of the 2009 Plan. The 2015 Plan is administered by the board of directors or a committee appointed by the board of directors, which determines the types of awards to be granted, including the number of shares subject to the awards, the exercise price and the vesting schedule. The exercise price of incentive stock options and nonqualified stock options will be no less than 100% of the fair value per share of the Company’s common stock on the date of grant. If an individual owns capital stock representing more than 10% of the voting shares, the price of each share will be at least 110% of the fair value on the date of grant. Options expire after 10 years (five years for stockholders owning greater than 10% of the voting stock). The number of shares of common stock initially reserved for issuance under the 2015 Plan was 6,134,292 shares with an automatic annual increase to the shares issuable under the 2015 Plan equal to the lower of (i) 4% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (ii) a lower number determined by the board of directors. On January 1, 2018 the shares issuable under the 2015 Plan increased by 3,109,448. The Company had 6,343,313 shares available for future grant under the 2015 Plan as of September 30, 2018. 2009 Plan The 2009 Plan terminated on the date the 2015 Plan was adopted. Options granted or shares issued under the 2009 Plan that were outstanding on the date the 2015 Plan became effective will remain subject to the terms of the 2009 Plan. At September 30, 2018, options to purchase 3,562,435 shares of common stock under the 2009 Plan remained outstanding. Stock Options The following table summarizes stock option activity for the nine months ended September 30, 2018: Options Outstanding Shares Available for Grant Number of Shares Underlying Options Weighted- Average Exercise Price Aggregate Intrinsic Value (In Balance—December 31, 2017 6,117,580 9,076,018 $ 8.04 $ 32,256 Authorized 3,109,448 — RSUs granted, net of forfeitures (796,305 ) — Granted (3,038,250 ) 3,038,250 6.20 Exercised — (1,314,739 ) 1.03 Canceled 950,840 (1) (1,097,127 ) 12.51 Balance—September 30, 2018 6,343,313 9,702,402 $ 7.91 $ 25,683 Options exercisable—September 30, 2018 5,846,632 $ 7.41 $ 22,042 Options vested and expected to vest—September 30, 2018 9,511,787 $ 7.91 $ 25,514 (1) This excludes 146,287 subject to canceled options for the nine months ended September 30, 2018 initially granted from the legacy stock option plans. As these plans have been terminated, any options canceled are not added back to the existing option plan pool. The aggregate intrinsic value represents the difference between the exercise price of the options and the closing price of the Company’s common stock. The aggregate intrinsic value of options exercised for the three and nine months ended September 30, 2018 was $463,000 and $8.8 million, respectively. As of September 30, 2018, the total unrecognized compensation expense related to unvested options, net of estimated forfeitures, was $19.9 million, which the Company expects to recognize over an estimated weighted-average period of 2.7 years. Restricted Stock Units (RSUs) In September 2016, the Company’s board of directors authorized the issuance of Restricted Stock Units, or RSUs, under the 2015 Plan and adopted a form of Restricted Stock Unit Grant Notice and Restricted Stock Unit Award Agreement, or the RSU Agreement, which is intended to serve as a standard form agreement for RSU grants issued to employees, executive officers, directors and consultants. The following table summarizes RSU activity for the nine months ended September 30, 2018: RSUs Outstanding Number of Restricted Units Weighted- Average Grant Date Fair Share Balance—December 31, 2017 1,436,623 $ 11.47 Granted 1,089,450 6.94 Vested (262,856 ) 12.33 Canceled/forfeited (293,145 ) 11.85 Balance—September 30, 2018 1,970,072 $ 8.79 The fair value of RSUs is determined on the date of grant based on the market price of the Company’s common stock on that date. As of September 30, 2018, there was $16.3 million of unrecognized stock-based compensation expense, net of estimated forfeitures, related to RSUs to be recognized over a weighted-average period of 3.4 years. 2015 Employee Stock Purchase Plan In March 2015, the Company’s board of directors adopted and in April 2015 the Company’s stockholders approved the 2015 Employee Stock Purchase Plan, or the 2015 ESPP, which became effective upon the IPO. The 2015 ESPP is intended to qualify as an employee stock purchase plan under Section 423 of the Internal Revenue Code, or the Code, and is administered by the Company’s board of directors and the Compensation Committee of the board of directors. The number of shares of common stock initially reserved for issuance under the 2015 ESPP was 720,000 shares with an automatic annual increase to the shares issuable under the 2015 ESPP equal to the lower of (i) 1% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (ii) a lower number determined by the board of directors. There was no annual increase of shares issuable under the 2015 ESPP on January 1, 2018. The Company had 1,740,211 shares available for future issuance under the 2015 ESPP as of September 30, 2018. As of September 30, 2018, the total unrecognized compensation expense related to ESPP was $41,000, which the Company expects to recognize over an estimated weighted-average period of 0.1 years. Stock-based Compensation Expense Total stock-based compensation expense recognized was as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Research and development $ 2,230 $ 2,118 $ 7,514 $ 6,711 General and administrative 1,991 1,906 5,958 5,299 Total stock-based compensation expense $ 4,221 $ 4,024 $ 13,472 $ 12,010 In determining the fair value of the stock-based awards, the Company uses the Black-Scholes option-pricing model. The fair value of stock option awards granted to employees was estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions: Option Plan ESPP Nine Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Expected term (in years) 5.32 - 6.05 5.31 - 6.04 0.5 0.5 Volatility 70.9 - 71.7% 73.2 - 74.1% 54.5% 65.4% Risk-free interest rate 2.38 - 2.89% 1.78 - 2.25% 2.09% 1.02% Dividend yield —% —% —% —%

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes Income tax benefit for the three months ended September 30, 2018 and 2017 was approximately $385,000 and $3.9 million, respectively, and $444,000 and $10.4 million for the nine months ended September 30, 2018 and 2017, respectively. The income tax benefit recorded for the nine months ended September 30, 2018 related primarily to the carryback of net operating losses from 2017 to 2016. The income tax benefit recorded in 2017 primarily related to the current benefit of federal income taxes paid in 2016. The Company files income tax returns in the United States and the Netherlands. The federal and state income tax returns are open under the statute of limitations subject to tax examinations for the tax years ended December 31, 2014 through December 31, 2017. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the IRS or state tax authorities to the extent utilized in a future period. For the Netherlands, the tax administration can impose an additional assessment within five years from the year in which the tax debt originated. Also, on December 22, 2017, the SEC issued Staff Accounting Bulletin 118, which provides guidance on accounting for tax effects of the Tax Act. SAB 118 provides a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under ASC 740. In accordance with SAB 118, a company must reflect the income tax effects of those aspects of the Tax Act for which the accounting under ASC 740 is complete. To the extent that a company’s accounting for certain income tax effects of the Tax Act is incomplete but it is able to determine a reasonable estimate, it must record a provisional estimate to be included in the financial statements. Provisional amounts or adjustments to provisional amounts identified in the measurement period, as defined, would be included as an adjustment to tax expense or benefit from continuing operations in the period the amounts are determined. During the third quarter of 2018, the Company has completed its analysis of the Tax Act and does not have any provisional amounts subject to SAB 118. As of September 30, 2018, Aduro recorded a current income tax receivable of $17.8 million. The current income tax receivable relates to the 2017 net operating loss. Pursuant to Code Section 172(f), the Company has filed a claim to carryback losses from 2017 to 2016. The Company filed this claim in September 2018 and the claim was $346,000 higher than originally estimated, resulting in an additional tax benefit. The Company expects to receive the refund by the end of 2018.

Net Loss Per Common Share

Net Loss Per Common Share	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Net Loss Per Common Share	11. Net Loss per Common Share Since the Company was in a loss position for all periods presented, diluted net loss per common share is the same as basic net loss per common share for all periods presented as the inclusion of all potential common shares outstanding would have been anti-dilutive. Potentially dilutive securities that were not included in the diluted per common share calculations because they would be anti-dilutive were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Options to purchase common stock 9,702,402 9,589,282 9,702,402 9,589,282 Restricted stock units 1,970,072 1,186,575 1,970,072 1,186,575 Common stock warrants 63,661 66,978 63,661 66,978 Total 11,736,135 10,842,835 11,736,135 10,842,835

Basis of Presentation, Use of_2

Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP, and follow the requirements of the Securities and Exchange Commission, or the SEC, for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2017 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements. These financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair presentation of the Company’s financial information. The results of operations for the three and nine months ended September 30, 2018 are not necessarily indicative of the results to be expected for the year ending December 31, 2018 or for any other interim period or for any other future year. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto for the year ended December 31, 2017 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 filed with the SEC on March 1, 2018. The consolidated financial statements include the accounts of Aduro Biotech, Inc. and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities and reported amounts of revenue and expenses in the financial statements and accompanying notes. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, clinical trial accruals, contingent consideration, income taxes and stock-based compensation. Management bases its estimates on historical experience and on various other market-specific and relevant assumptions that management believes to be reasonable under the circumstances. Actual results could differ from these estimates.
Revenue Recognition	Revenue Recognition The Company recognizes revenue when its customers obtain control of the promised goods or services, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods or services. Collaboration and license revenue The Company’s collaboration agreements may include the transfer of intellectual property rights in the form of licenses, obligations to provide research and development services and obligations to participate on certain development committees with the collaboration party. The terms of such agreements include payment to the Company of one or more of the following: nonrefundable upfront fees, payment for research and development services, development, regulatory and commercial milestone payments, and royalties on net sales of licensed products. The Company assesses whether the promises in these agreements are considered distinct performance obligations that should be accounted for separately. Judgment is required to determine whether the license to the Company’s intellectual property is distinct from the research and development services or participation on development committees. The transaction price in each agreement is allocated to the identified performance obligations based on the standalone selling price, or SSP, of each distinct performance obligation. Judgment is required to determine SSP. In instances where SSP is not directly observable, such as when a license or service is not sold separately, SSP is determined using information that may include market conditions and other observable inputs. Due to the early stage of the Company’s licensed technology, the license of such technology is typically combined with the research and development services and committee participation as one performance obligation. Revenue associated with nonrefundable upfront license fees where the license fees and research and development services cannot be accounted for as separate performance obligations is deferred and recognized as revenue over the expected period of performance using a cost-based input methodology. The Company utilizes judgment to assess the pattern of delivery of the performance obligation. At the inception of each agreement that includes development, regulatory or commercial milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price by using the most likely amount method. If it is probable that a significant reversal of cumulative revenue would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received or the underlying activity has been completed. The transaction price is then allocated to each performance obligation in the agreement based on relative SSP. At the end of each subsequent reporting period, the Company re-evaluates the probability of achievement of each such milestone and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment.
Contract Balances	Contract Balances Upfront payments and fees are recorded as deferred revenue upon receipt or when due, and may require deferral of revenue recognition to a future period until the Company performs its obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In February 2016, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2016-02, Leases (Topic 842), which establishes a comprehensive new lease accounting model. The new standard: (a) clarifies the definition of a lease; (b) requires a dual approach to lease classification similar to current lease classifications; and (c) causes lessees to recognize leases on the balance sheet as a lease liability with a corresponding right-of-use asset for leases with a lease-term of more than twelve months. The new standard is effective for fiscal years and interim periods beginning after December 15, 2018, with early adoption permitted. A modified retrospective transition approach is required for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, including a number of optional practical expedients that entities may elect to apply. In July 2018, the FASB issued ASU No. 2018-11, Leases (Topic 842): Targeted Improvements, an update which provides another transition method, in addition to the existing modified retrospective transition method, by allowing entities to initially apply the new lease standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. In preparation for adoption of the standard, the Company engaged a third-party service provider to assist the Company with the evaluation. The Company has identified all leases and is currently reviewing the leases to determine the impact of the update on the Company’s consolidated financial statements. The Company is planning to adopt the new standard by initially applying the guidance at the adoption date, January 1, 2019, and recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption as permitted by ASU No. 2018-11. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326). The standard changes how entities will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. Financial assets measured at amortized cost will be presented at the net amount expected to be collected by using an allowance for credit losses. The standard is effective for fiscal years and interim periods beginning after December 15, 2019. Early adoption is permitted for all periods beginning after December 15, 2018. The Company has evaluated the impact of this guidance and has concluded that adoption of the standard will not have a material impact on its consolidated financial statements. In February 2018, the FASB issued ASU No. 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220). The standard update allows for a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act of 2017, or the Tax Act. Consequently, the ASU 2018-02 eliminates the stranded tax effects resulting from the Tax Act. The new standard is effective for fiscal years and interim periods beginning after December 15, 2018. Early adoption is permitted, including adoption in any interim period for reporting periods for which financial statements have not yet been issued. The new standard should be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Act is recognized. The Company has evaluated the impact of this guidance and has concluded that adoption of the standard will not have a material impact on its consolidated financial statements. In June 2018, the FASB issued ASU No. 2018-07 – Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Shared-Based Payment Accounting. The standard update expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The new standard simplifies several aspects of Topic 718 by expanding the scope of the following areas to account for nonemployee shared-based payment transactions: (1) overall measurement objective, (2) measurement date, (3) awards with performance conditions, and (4) classification reassessment of certain equity-classified awards. The new standard is effective for fiscal years and interim periods beginning after December 15, 2018. Early adoption is permitted, but no earlier than an entity’s adoption date of Topic 606. The Company has evaluated the impact of this guidance and has concluded that adoption of the standard will not have a material impact on its consolidated financial statements.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments--Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which amends the guidance in U.S. GAAP on the classification and measurement of financial instruments. In February 2018, the FASB issued ASU No. 2018-03 which provides additional clarification and implementation guidance on the previously issued ASU No. 2016-01. Changes to the current guidance primarily affect the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. In addition, the ASU clarifies guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on available-for-sale debt securities. The new standard is effective for fiscal years and interim periods beginning after December 15, 2017, and upon adoption, an entity should apply the amendments by means of a cumulative-effect adjustment to the balance sheet at the beginning of the first reporting period in which the guidance is effective. The Company adopted this ASU on January 1, 2018. The adoption of the standard did not have a material impact on its condensed consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). This ASU as well as its related amendments affect any entity that either enters into contracts with customers to transfer goods and services or enters into contracts for the transfer of nonfinancial assets. ASU 2014-09 replaced most existing revenue recognition guidance in U.S. GAAP when it became effective. The standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which it expects to be entitled in exchange for those goods or services. The Company adopted this standard on January 1, 2018 using the modified retrospective method. The Company recognized the cumulative effect of initially applying the new revenue standard as an adjustment to the opening balance of its accumulated deficit. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. As a result, the Company changed its accounting policy for revenue recognition, and the details of the significant changes and quantitative impact of the changes are disclosed below. Milestone payments – under the milestone method ASC 605-28, payments that were contingent upon the achievement of a substantive milestone were recognized entirely as revenue in the period in which the milestone was achieved. To the extent that non-substantive milestones were achieved and the Company had remaining performance obligations, milestones were deferred and recognized as revenue over the estimated remaining period of performance. If there were no remaining performance obligations, the revenue from non-substantive milestones was recognized in the period it was earned. The milestone method no longer exists under the new revenue standard. The revenue from the milestone payments must be estimated using either the expected value method or the most likely amount method. Revenue that is not probable of significant reversal of cumulative revenue is included in the transaction price. Therefore, substantive milestones that were recognized when achieved under the legacy revenue guidance will be recognized as revenue over the performance period under the new standard with a cumulative catch-up recorded for the portion associated with the performance to date. Pattern of revenue recognition – the Company recognized revenue from performance obligations delivered over time, such as licenses combined with research and development services and participation on development committees, on a straight-line basis over the period of performance under the legacy revenue guidance. The new standard allows entities to use either an input method or an output method to measure progress toward complete satisfaction of a performance obligation. For contracts in progress at the adoption date of the new standard the Company determined that the input method of measuring costs incurred to date compared to total estimated costs to be incurred under the contract most accurately depicts its performance. The change in the pattern of revenue recognition upon adoption of Topic 606 for milestone payments and performance obligations delivered over time resulted in an increase in the balance of deferred revenue and an increase in the accumulated deficit balance of $25.3 million on January 1, 2018. The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated balance sheet line items (in thousands): September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) Liabilities Deferred revenue $ 17,744 $ (2,929 ) $ 14,815 Deferred revenue – noncurrent 161,591 (24,554 ) 137,037 Stockholders’ Equity Accumulated deficit (378,212 ) 27,483 (350,729 ) The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated statement of operations line items (in thousands, except per share data): Three Months Ended September 30, 2018 Nine Months Ended September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) (in thousands) Collaboration and license revenue $ 3,063 $ 866 $ 3,929 $ 12,329 $ 2,171 $ 14,500 Total revenue 3,063 866 3,929 12,329 2,171 14,500 Loss from operations (24,905 ) 866 (24,039 ) (73,358 ) 2,171 (71,187 ) Net loss (23,146 ) 866 (22,280 ) (69,037 ) 2,171 (66,866 ) Net loss per share, basic and diluted (0.29 ) 0.01 (0.28 ) (0.88 ) 0.03 (0.85 ) The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated statement of cash flows line items (in thousands): Nine Months Ended September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) Cash flows from operating activities Net loss $ (69,037 ) $ 2,171 $ (66,866 ) Changes in operating assets and liabilities: Deferred revenue (9,246 ) (2,171 ) (11,417 ) In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 identifies how certain cash receipts and cash payments are presented and classified in the Statement of Cash Flows. The standard is effective for fiscal years and interim periods beginning after December 15, 2017. The standard should be applied retrospectively, and early adoption is permitted, including adoption in an interim period. The Company adopted this standard on January 1, 2018 and the adoption of the standard did not have a material impact on its condensed consolidated statement of cash flows. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. ASU 2016-18 requires that the statement of cash flows explain the change during the period in the total cash, cash equivalents, and restricted cash. The standard is effective for fiscal years beginning after December 15, 2017, and interim periods within those years. This standard should be applied retrospectively and early adoption is permitted, including adoption in an interim period. The Company adopted this standard on January 1, 2018 utilizing the required retrospective transition method and changed the presentation and classification of restricted cash in its condensed consolidated statement of cash flows. In May 2017, the FASB issued ASU No. 2017-09, Compensation – Stock Compensation (Topic 718): Scope of Modification Accounting. ASU 2017-09 provides clarity and reduces the complexity of applying the guidance in Topic 718, Compensation – Stock Compensation, to a change to the terms or conditions of a share-based payment award. This standard is effective for annual periods beginning after December 15, 2017. The Company adopted this ASU on January 1, 2018, and the In March 2018, the FASB issued ASU No. 2018-05, Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118, which included amendments to expand income tax accounting and disclosure guidance pursuant to SEC Staff Accounting Bulletin No. 118 (“SAB 118”) issued by the SEC in December 2017. SAB 118 provides guidance on accounting for the income tax effects of the Tax Act. The Company adopted this ASU in the first quarter of 2018. Refer to Note 10 Income Taxes for more information and disclosures related to this amended guidance.

Basis of Presentation, Use of_3

Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements (Tables) - ASU 2014-09	9 Months Ended
	Sep. 30, 2018
Summary of Impact of Adopting Topic 606 on Unaudited Condensed Consolidated Balance Sheet	The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated balance sheet line items (in thousands): September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) Liabilities Deferred revenue $ 17,744 $ (2,929 ) $ 14,815 Deferred revenue – noncurrent 161,591 (24,554 ) 137,037 Stockholders’ Equity Accumulated deficit (378,212 ) 27,483 (350,729 )
Summary of Impact of Adopting Topic 606 on Unaudited Condensed Consolidated Statement of Operations	The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated statement of operations line items (in thousands, except per share data): Three Months Ended September 30, 2018 Nine Months Ended September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) (in thousands) Collaboration and license revenue $ 3,063 $ 866 $ 3,929 $ 12,329 $ 2,171 $ 14,500 Total revenue 3,063 866 3,929 12,329 2,171 14,500 Loss from operations (24,905 ) 866 (24,039 ) (73,358 ) 2,171 (71,187 ) Net loss (23,146 ) 866 (22,280 ) (69,037 ) 2,171 (66,866 ) Net loss per share, basic and diluted (0.29 ) 0.01 (0.28 ) (0.88 ) 0.03 (0.85 )
Summary of Impact of Adopting Topic 606 on Unaudited Condensed Consolidated Statement of Cash Flows	The following table summarizes the impact of adopting Topic 606 on select unaudited condensed consolidated statement of cash flows line items (in thousands): Nine Months Ended September 30, 2018 As reported Adjustments Balances without the adoption of Topic 606 (in thousands) Cash flows from operating activities Net loss $ (69,037 ) $ 2,171 $ (66,866 ) Changes in operating assets and liabilities: Deferred revenue (9,246 ) (2,171 ) (11,417 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): September 30, 2018 Level 1 Level 2 Level 3 Total Financial Assets: Money market funds $ 28,243 $ — $ — $ 28,243 U.S. government and agency securities — 73,492 — 73,492 Corporate debt securities — 66,244 — 66,244 Commercial paper — 89,587 — 89,587 Total $ 28,243 $ 229,323 $ — $ 257,566 Financial Liabilities: Contingent consideration related to acquisition $ — $ — $ 941 $ 941 Total $ — $ — $ 941 $ 941 December 31, 2017 Level 1 Level 2 Level 3 Total Financial Assets: Money market funds $ 86,461 $ — $ — $ 86,461 U.S. government and agency securities — 108,076 — 108,076 Corporate debt securities — 58,496 — 58,496 Commercial paper — 74,011 — 74,011 Total $ 86,461 $ 240,583 $ — $ 327,044 Financial Liabilities: Contingent consideration related to acquisition $ — $ — $ 7,588 $ 7,588 Total $ — $ — $ 7,588 $ 7,588
Summary of Changes in Fair Value of Level 3 Financial Liabilities	The following table sets forth a summary of the changes in the fair value of the Company’s Level 3 financial liabilities (in thousands): Contingent Consideration Balance at December 31, 2017 $ 7,588 Net change in fair value upon remeasurement 574 Payment of contingent considerations (6,803 ) Foreign currency impact on contingent consideration (418 ) Balance at September 30, 2018 $ 941
Summary of Estimated Value of Cash, Cash Equivalents and Marketable Securities and Gross Unrealized Holding Gains and Losses	The following tables summarize the estimated value of the Company’s cash, cash equivalents and marketable securities and the gross unrealized holding gains and losses (in thousands): September 30, 2018 Amortized cost Unrealized gains Unrealized losses Estimated Fair Value Cash and cash equivalents: Cash $ 21,068 $ — $ — $ 21,068 Money market funds 28,243 — — 28,243 Commercial paper 70,840 — — 70,840 U.S. government and agency securities 600 — — 600 Total cash and cash equivalents $ 120,751 $ — $ — $ 120,751 Marketable securities: U.S. government and agency securities $ 73,138 $ — $ (246 ) $ 72,892 Corporate debt securities 66,278 1 (35 ) 66,244 Commercial paper 18,747 — — 18,747 Total marketable securities $ 158,163 $ 1 $ (281 ) $ 157,883 December 31, 2017 Amortized cost Unrealized gains Unrealized losses Estimated Fair Value Cash and cash equivalents: Cash $ 22,673 $ — $ — $ 22,673 Money market funds 86,461 — — 86,461 Commercial paper 48,480 — — 48,480 Total cash and cash equivalents $ 157,614 $ — $ — $ 157,614 Marketable securities: U.S. government and agency securities $ 108,317 $ — $ (241 ) $ 108,076 Corporate debt securities 58,551 1 (56 ) 58,496 Commercial paper 25,531 — — 25,531 Total marketable securities $ 192,399 $ 1 $ (297 ) $ 192,103
Summary of Amortized Cost and Estimated Fair Value of Available-for-Sale Marketable Securities by Contractual Maturity	The amortized cost and estimated fair value of the Company’s available-for-sale marketable securities by contractual maturity are summarized below as of September 30, 2018 (in thousands): Amortized cost Estimated Fair Mature in one year or less $ 145,279 $ 145,043 Mature after one year through two years 12,884 12,840 Total available-for-sale marketable securities $ 158,163 $ 157,883

Balance Sheet Components (Table

Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2018
Balance Sheet Related Disclosures [Abstract]
Summary of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): September 30, December 31, 2018 2017 Leasehold improvements $ 26,964 $ 27,102 Lab equipment 8,081 7,243 Computer and office equipment 2,171 2,016 Furniture 1,750 1,767 Construction in progress 1,304 54 Total property and equipment 40,270 38,182 Less: accumulated depreciation (10,464 ) (7,097 ) Property and equipment, net $ 29,806 $ 31,085
Accrued Expenses and Other Liabilities	Accrued Expenses and Other Liabilities Accrued expenses and other liabilities consisted of the following (in thousands): September 30, December 31, 2018 2017 Compensation and related benefits $ 3,782 $ 5,320 Professional and consulting services 1,864 1,586 Accrued research expense 833 1,763 Deferred rent 627 434 Accrued property and equipment 309 2,790 Other 1,186 708 Total accrued expenses and other liabilities $ 8,601 $ 12,601

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The gross carrying amount of goodwill was as follows (in thousands): Balance at December 31, 2017 $ 8,723 Foreign currency translation adjustment (274 ) Balance at September 30, 2018 $ 8,449
Schedule of Intangible Assets	The gross carrying amounts and net book value of intangible assets were as follows (in thousands): September 30, 2018 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: License agreement $ 11,474 $ 1,673 $ 9,801 Total intangible assets with finite lives 11,474 1,673 9,801 Acquired IPR&D assets 19,897 — 19,897 Total intangible assets $ 31,371 $ 1,673 $ 29,698 December 31, 2017 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: License agreement $ 11,847 $ 1,283 $ 10,564 Total intangible assets with finite lives 11,847 1,283 10,564 Acquired IPR&D assets 20,543 — 20,543 Total intangible assets $ 32,390 $ 1,283 $ 31,107
Schedule of Finite-Lived Intangible Assets Estimated Future Amortization Expense	Based on finite-lived intangible assets recorded as of September 30, 2018, the estimated future amortization expense is as follows (in thousands): Year Ending December 31, Estimated Amortization Expense 2018 (remaining three months) $ 143 2019 574 2020 574 2021 574 2022 574 2023 574

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2018
Commitments And Contingencies Disclosure [Abstract]
Schedule of Future Minimum Payments under the Leases	Future minimum payments under the leases at September 30, 2018 are as follows (in thousands): Year Ending December 31, Amounts 2018 (remaining three months) $ 1,500 2019 5,525 2020 5,676 2021 5,332 2022 5,460 Thereafter 41,406 Total $ 64,899

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity	Stock Options The following table summarizes stock option activity for the nine months ended September 30, 2018: Options Outstanding Shares Available for Grant Number of Shares Underlying Options Weighted- Average Exercise Price Aggregate Intrinsic Value (In Balance—December 31, 2017 6,117,580 9,076,018 $ 8.04 $ 32,256 Authorized 3,109,448 — RSUs granted, net of forfeitures (796,305 ) — Granted (3,038,250 ) 3,038,250 6.20 Exercised — (1,314,739 ) 1.03 Canceled 950,840 (1) (1,097,127 ) 12.51 Balance—September 30, 2018 6,343,313 9,702,402 $ 7.91 $ 25,683 Options exercisable—September 30, 2018 5,846,632 $ 7.41 $ 22,042 Options vested and expected to vest—September 30, 2018 9,511,787 $ 7.91 $ 25,514 (1) This excludes 146,287 subject to canceled options for the nine months ended September 30, 2018 initially granted from the legacy stock option plans. As these plans have been terminated, any options canceled are not added back to the existing option plan pool.
Summary of RSU Activity	The following table summarizes RSU activity for the nine months ended September 30, 2018: RSUs Outstanding Number of Restricted Units Weighted- Average Grant Date Fair Share Balance—December 31, 2017 1,436,623 $ 11.47 Granted 1,089,450 6.94 Vested (262,856 ) 12.33 Canceled/forfeited (293,145 ) 11.85 Balance—September 30, 2018 1,970,072 $ 8.79
Summary of Stock-Based Compensation	Total stock-based compensation expense recognized was as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Research and development $ 2,230 $ 2,118 $ 7,514 $ 6,711 General and administrative 1,991 1,906 5,958 5,299 Total stock-based compensation expense $ 4,221 $ 4,024 $ 13,472 $ 12,010
Schedule of Black-Scholes Option-Pricing Model	The fair value of stock option awards granted to employees was estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions: Option Plan ESPP Nine Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Expected term (in years) 5.32 - 6.05 5.31 - 6.04 0.5 0.5 Volatility 70.9 - 71.7% 73.2 - 74.1% 54.5% 65.4% Risk-free interest rate 2.38 - 2.89% 1.78 - 2.25% 2.09% 1.02% Dividend yield —% —% —% —%

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Schedule of Potentially Dilutive Securities not Included in Calculation of Diluted Per Common Share	Potentially dilutive securities that were not included in the diluted per common share calculations because they would be anti-dilutive were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Options to purchase common stock 9,702,402 9,589,282 9,702,402 9,589,282 Restricted stock units 1,970,072 1,186,575 1,970,072 1,186,575 Common stock warrants 63,661 66,978 63,661 66,978 Total 11,736,135 10,842,835 11,736,135 10,842,835

Organization and Nature of Bu_2

Organization and Nature of Business - Additional Information (Details)	9 Months Ended
	Sep. 30, 2018Segment
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Number of business segments	1

Basis of Presentation, Use of_4

Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements - Additional Information (Details) $ in Millions	Jan. 01, 2018USD ($)
ASU 2014-09
Summary Of Significant Accounting Policies [Line Items]
Increase in balance of deferred revenue and increase in accumulated deficit balance	$ 25.3

Basis of Presentation, Use of_5

Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements - Summary of Impact of Adopting Topic 606 on Unaudited Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Liabilities
Deferred revenue	$ 17,744	$ 14,923
Deferred revenue – noncurrent	161,591	148,148
Stockholders’ equity:
Accumulated deficit	(378,212)	$ (283,863)
ASU 2014-09 | Adjustments
Liabilities
Deferred revenue	(2,929)
Deferred revenue – noncurrent	(24,554)
Stockholders’ equity:
Accumulated deficit	27,483
ASU 2014-09 | Balances Without the Adoption of Topic 606
Liabilities
Deferred revenue	14,815
Deferred revenue – noncurrent	137,037
Stockholders’ equity:
Accumulated deficit	$ (350,729)

Basis of Presentation, Use of_6

Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements - Summary of Impact of Adopting Topic 606 on Unaudited Condensed Consolidated Statement of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 3,063	$ 3,794	$ 12,329	$ 13,483
Loss from operations	(24,905)	(29,263)	(73,358)	(78,376)
Net loss	$ (23,146)	$ (24,520)	$ (69,037)	$ (65,731)
Net loss per common share, basic and diluted	$ (0.29)	$ (0.33)	$ (0.88)	$ (0.92)
Collaboration and License Revenue
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 3,063	$ 3,704	$ 12,329	$ 13,352
ASU 2014-09 | Adjustments
Summary Of Significant Accounting Policies [Line Items]
Total revenue	866		2,171
Loss from operations	866		2,171
Net loss	$ 866		$ 2,171
Net loss per common share, basic and diluted	$ 0.01		$ 0.03
ASU 2014-09 | Balances Without the Adoption of Topic 606
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 3,929		$ 14,500
Loss from operations	(24,039)		(71,187)
Net loss	$ (22,280)		$ (66,866)
Net loss per common share, basic and diluted	$ (0.28)		$ (0.85)
ASU 2014-09 | Collaboration and License Revenue | Adjustments
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 866		$ 2,171
ASU 2014-09 | Collaboration and License Revenue | Balances Without the Adoption of Topic 606
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 3,929		$ 14,500

Basis of Presentation, Use of_7

Basis of Presentation, Use of Estimates and Recent Accounting Pronouncements - Summary of Impact of Adopting Topic 606 on Unaudited Condensed Consolidated Statement of Cash Flows (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows from Operating Activities
Net loss	$ (69,037)	$ (65,731)
Changes in operating assets and liabilities:
Deferred revenue	(9,246)	$ (11,218)
ASU 2014-09 | Adjustments
Cash Flows from Operating Activities
Net loss	2,171
Changes in operating assets and liabilities:
Deferred revenue	(2,171)
ASU 2014-09 | Balances Without the Adoption of Topic 606
Cash Flows from Operating Activities
Net loss	(66,866)
Changes in operating assets and liabilities:
Deferred revenue	$ (11,417)

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financial Assets:
Financial Assets, fair value	$ 257,566	$ 327,044
Financial Liabilities:
Financial Liabilities, fair value	941	7,588
Contingent Consideration Related To Acquisition
Financial Liabilities:
Financial Liabilities, fair value	941	7,588
Money Market Funds
Financial Assets:
Financial Assets, fair value	28,243	86,461
U.S. Government and Agency Securities
Financial Assets:
Financial Assets, fair value	73,492	108,076
Corporate Debt Securities
Financial Assets:
Financial Assets, fair value	66,244	58,496
Commercial Paper
Financial Assets:
Financial Assets, fair value	89,587	74,011
Level 1
Financial Assets:
Financial Assets, fair value	28,243	86,461
Level 1 | Money Market Funds
Financial Assets:
Financial Assets, fair value	28,243	86,461
Level 2
Financial Assets:
Financial Assets, fair value	229,323	240,583
Level 2 | U.S. Government and Agency Securities
Financial Assets:
Financial Assets, fair value	73,492	108,076
Level 2 | Corporate Debt Securities
Financial Assets:
Financial Assets, fair value	66,244	58,496
Level 2 | Commercial Paper
Financial Assets:
Financial Assets, fair value	89,587	74,011
Level 3
Financial Liabilities:
Financial Liabilities, fair value	941	7,588
Level 3 | Contingent Consideration Related To Acquisition
Financial Liabilities:
Financial Liabilities, fair value	$ 941	$ 7,588

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets transferred from level 1 to level 2	$ 0	$ 0	$ 0
Fair value assets transferred from level 2 to level 1	0	0	0
Fair value liabilities transferred from level 1 to level 2	0	0	0
Fair value liabilities transferred from level 2 to level 1	0	0	0
Fair value assets transferred into level 3		0	0
Fair value assets transferred out of level 3		0	0
Fair value liabilities transferred into level 3		0	0
Fair value liabilities transferred out of level 3		0	0
Fair Value, Measurements, Nonrecurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Financial assets measured at fair value on a nonrecurring basis	0	0	0
Financial liabilities measured at fair value on a nonrecurring basis	0	$ 0	$ 0
BioNovion Holding B.V.
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Payment of contingent consideration	$ 6,800,000

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Changes in Fair Value of Level 3 Financial Liabilities (Details) - Contingent Consideration $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Beginning balance	$ 7,588
Net change in fair value upon remeasurement	574
Payment of contingent considerations	(6,803)
Foreign currency impact on contingent consideration	(418)
Ending balance	$ 941

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Estimated Value of Cash, Cash Equivalents and Marketable Securities and Gross Unrealized Holding Gains and Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, Amortized cost	$ 120,751	$ 157,614	$ 159,040
Cash and cash equivalents, Estimated Fair Value	120,751	157,614
Marketable securities, Amortized cost	158,163	192,399
Marketable securities, Unrealized gains	1	1
Marketable securities, Unrealized losses	(281)	(297)
Marketable securities, Estimated Fair Value	157,883	192,103
Cash
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, Amortized cost	21,068	22,673
Cash and cash equivalents, Estimated Fair Value	21,068	22,673
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, Amortized cost	28,243	86,461
Cash and cash equivalents, Estimated Fair Value	28,243	86,461
Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, Amortized cost	70,840	48,480
Cash and cash equivalents, Estimated Fair Value	70,840	48,480
U.S. Government and Agency Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, Amortized cost	600
Cash and cash equivalents, Estimated Fair Value	600
Marketable securities, Amortized cost	73,138	108,317
Marketable securities, Unrealized losses	(246)	(241)
Marketable securities, Estimated Fair Value	72,892	108,076
Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, Amortized cost	66,278	58,551
Marketable securities, Unrealized gains	1	1
Marketable securities, Unrealized losses	(35)	(56)
Marketable securities, Estimated Fair Value	66,244	58,496
Commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, Amortized cost	18,747	25,531
Marketable securities, Estimated Fair Value	$ 18,747	$ 25,531

Fair Value Measurements - Sum_3

Fair Value Measurements - Summary of Amortized Cost and Estimated Fair Value of Available-for-Sale Marketable Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Mature in one year or less, Amortized cost	$ 145,279
Mature after one year through two years, Amortized cost	12,884
Marketable securities, Amortized cost	158,163	$ 192,399
Mature in one year or less, Estimated Fair Value	145,043
Mature after one year through two years, Estimated Fair Value	12,840
Total available-for-sale marketable securities, Estimated Fair Value	$ 157,883	$ 192,103

Balance Sheet Components - Summ

Balance Sheet Components - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 40,270	$ 38,182
Less: accumulated depreciation	(10,464)	(7,097)
Property and equipment, net	29,806	31,085
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	26,964	27,102
Lab Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	8,081	7,243
Computer and Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,171	2,016
Furniture
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,750	1,767
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,304	$ 54

Balance Sheet Components - Addi

Balance Sheet Components - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Balance Sheet Related Disclosures [Abstract]
Depreciation	$ 1,100,000	$ 888,000	$ 3,300,000	$ 2,500,000

Balance Sheet Components - Su_2

Balance Sheet Components - Summary of Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Compensation and related benefits	$ 3,782	$ 5,320
Professional and consulting services	1,864	1,586
Accrued research expense	833	1,763
Deferred rent	627	434
Accrued property and equipment	309	2,790
Other	1,186	708
Total accrued expenses and other liabilities	$ 8,601	$ 12,601

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at December 31, 2017	$ 8,723
Foreign currency translation adjustment	(274)
Balance at September 30, 2018	$ 8,449

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Finite Lived Intangible Assets, Gross Carrying Amount	$ 11,474	$ 11,847
Finite Lived Intangible Assets, Accumulated Amortization	1,673	1,283
Finite Lived Intangible Assets, Net Book Value	9,801	10,564
Intangible Assets, Gross Carrying Amount	31,371	32,390
Intangible assets, Net Book Value	29,698	31,107
License agreement
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Finite Lived Intangible Assets, Gross Carrying Amount	11,474	11,847
Finite Lived Intangible Assets, Accumulated Amortization	1,673	1,283
Finite Lived Intangible Assets, Net Book Value	9,801	10,564
Acquired IPR&D assets
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets, Gross Carrying Amount	$ 19,897	$ 20,543

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Goodwill And Intangible Assets [Line Items]
Amortization of intangible assets	$ 144	$ 145	$ 443	$ 413
Novartis
Goodwill And Intangible Assets [Line Items]
Intangible assets, amortization period			20 years

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Schedule of Finite-Lived Intangible Assets Estimated Future Amortization Expense (Details) $ in Thousands	Sep. 30, 2018USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
2018 (remaining three months)	$ 143
2,019	574
2,020	574
2,021	574
2,022	574
2,023	$ 574

Collaboration Agreements - Addi

Collaboration Agreements - Additional Information (Details) - USD ($)

Sep. 25, 2018

Apr. 30, 2015

Sep. 30, 2018

Mar. 31, 2018

Sep. 30, 2017

Jun. 30, 2016

Sep. 30, 2018

Sep. 30, 2017

Dec. 31, 2017

Dec. 31, 2015

Oct. 31, 2015

Oct. 31, 2015

Sep. 30, 2018

Novartis Agreement

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Payments received under collaboration agreement

$ 200,000,000

$ 35,000,000

$ 1,300,000

Novartis share of joint development costs

38.00%

Period after first commercial sale of product on which Novartis' royalty obligation run on a country to country basis

12 years

Transaction price allocated to combined performance obligation

$ 236,300,000

Revenue recognized

$ 3,000,000

$ 3,700,000

9,100,000

$ 11,200,000

Deferred revenue

179,300,000

$ 179,300,000

179,300,000

Novartis Agreement | United States

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Collaborative arrangement profit share percentage

50.00%

Novartis Agreement | European Countries and Japan

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Collaborative arrangement profit share percentage

45.00%

Novartis Agreement | United States, Specified European Countries and /or Japan

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Collaborative Agreement, Obligations

With respect to the United States, specified European countries and/or Japan, the Company may elect for such region to either reduce by 50% or to eliminate in full the Company’s development and commercialization cost sharing obligation. If the Company elects to reduce its cost sharing percentage by 50% in any such region, then its profit share in such region will also be reduced by 50%. If the Company elects to eliminate its development cost sharing obligation, then such region will be removed from the profit share, and instead Novartis will owe the Company royalties on any net sales of product for such region, as described above.

Reduction percentage of development cost share

50.00%

Reduction percentage of profit share

50.00%

Novartis Agreement | Novartis

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Novartis share of joint development costs

62.00%

Collaborative arrangement profit share percentage

50.00%

Novartis Agreement | Maximum

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Development milestones amount eligible to receive

$ 215,000,000

Regulatory approval milestones amount eligible to receive

250,000,000

Janssen ADU-214 Agreement

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Payments received under collaboration agreement

$ 30,000,000

License agreement, termination effective date

Dec. 24, 2018

Revenue recognized for milestones

$ 21,000,000

Janssen ADU-741 and Janssen GVAX Prostate Agreement

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Payments received under collaboration agreement

$ 12,500,000

License agreement, termination effective date

Dec. 24, 2018

Revenue recognized for milestones

$ 10,000,000

Merck License Agreement

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Payments received under collaboration agreement

$ 3,000,000

$ 2,000,000

Remaining performance obligations

$ 0

0

$ 0

$ 0

Merck License Agreement | Maximum | Product Candidate

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Milestone amount eligible to receive for products or product candidates

307,000,000

Merck License Agreement | Maximum | Product

Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]

Milestone amount eligible to receive for products or product candidates

$ 135,000,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2018USD ($)ft²	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)ft²LeaseTerm	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2015ft²
Operating Leased Assets [Line Items]
Total square footage of leased property | ft²	25,000		25,000
Lease expiration date			Dec. 31, 2018
Security deposit | $	$ 468,000		$ 468,000		$ 468,000
Rent expense | $	1,400,000	$ 1,200,000	4,300,000	$ 4,100,000
Bank Of America Merrill Lynch
Operating Leased Assets [Line Items]
Letter of credit outstanding | $	$ 468,000		$ 468,000
Office/Laboratory Lease
Operating Leased Assets [Line Items]
Total square footage of leased property | ft²						110,853
Operating lease initial term	13 years 6 months		13 years 6 months
Lease expiration date			Dec. 31, 2029
Number of additional renewal terms | LeaseTerm			2
Additional operating lease term	5 years		5 years
Office/Laboratory Lease | Sublease
Operating Leased Assets [Line Items]
Total square footage of leased property | ft²	30,100		30,100
Lease expiration date			Dec. 31, 2020
Research and Development Facility | Netherlands
Operating Leased Assets [Line Items]
Operating leases term of expiration			2020-12

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Future Minimum Payments under the Leases (Details) $ in Thousands	Sep. 30, 2018USD ($)
Commitments And Contingencies Disclosure [Abstract]
2018 (remaining three months)	$ 1,500
2,019	5,525
2,020	5,676
2,021	5,332
2,022	5,460
Thereafter	41,406
Total	$ 64,899

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended	9 Months Ended		14 Months Ended
	Aug. 31, 2017	May 31, 2016	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2017
Stockholders' Equity [Line Items]
Net proceeds from issuance of common stock, after deducting commissions and expenses payable					$ 77,156,000
At-the-Market Offering | 2017 Sales Agreement | Cowen and Company, LLC
Stockholders' Equity [Line Items]
Commission on sales of common stock, percentage	3.00%
Issuance of common stock (in shares)			0	0
Aggregate offering available for issuance of common stock				$ 81,500,000
At-the-Market Offering | 2017 Sales Agreement | Cowen and Company, LLC | Maximum
Stockholders' Equity [Line Items]
Aggregate offering price from offer and sale of common stock	$ 100,000,000
At-the-Market Offering | 2016 Sales Agreement | Cowen and Company, LLC
Stockholders' Equity [Line Items]
Commission on sales of common stock, percentage		3.00%
Issuance of common stock (in shares)		8,350,018
Net proceeds from issuance of common stock, after deducting commissions and expenses payable						$ 97,300,000
Amounts remaining for future sales		$ 0

Equity Incentive Plans - Additi

Equity Incentive Plans - Additional Information (Details) - USD ($)	Jan. 01, 2018	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017	Apr. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issuable increased during the period			3,109,448
Number of shares available for future grant		6,343,313	6,343,313	6,117,580
Number of options outstanding		9,702,402	9,702,402	9,076,018
Aggregate intrinsic value of options exercised		$ 463,000	$ 8,800,000
Unrecognized compensation expense		19,900,000	$ 19,900,000
Weighted-average period of unrecognized compensation expense			2 years 8 months 12 days
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period of unrecognized compensation expense			3 years 4 months 24 days
Unrecognized stock-based compensation expense related to RSUs		$ 16,300,000	$ 16,300,000
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price to fair market value common stock on grant date			100.00%
Stock option expiration period			10 years
2015 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for issuance					6,134,292
Percentage of shares issued on common stock outstanding			4.00%
Common Stock Issuance Description			shares issuable under the 2015 Plan equal to the lower of (i) 4% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (ii) a lower number determined by the board of directors.
Shares issuable increased during the period	3,109,448
Number of shares available for future grant		6,343,313	6,343,313
2009 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options outstanding		3,562,435	3,562,435
2015 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for issuance					720,000
Percentage of shares issued on common stock outstanding			1.00%
Common Stock Issuance Description			shares issuable under the 2015 ESPP equal to the lower of (i) 1% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (ii) a lower number determined by the board of directors.
Shares issuable increased during the period	0
Number of shares available for future grant		1,740,211	1,740,211
Unrecognized compensation expense		$ 41,000	$ 41,000
Weighted-average period of unrecognized compensation expense			1 month 6 days
More Than 10% Voting Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option expiration period			5 years
More Than 10% Voting Shares | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price to fair market value common stock on grant date			110.00%

Equity Incentive Plans - Summar

Equity Incentive Plans - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options Outstanding, Shares Available for Grant, Beginning balance	6,117,580
Options Outstanding, Shares Available for Grant, Authorized	3,109,448
Options Outstanding, Shares Available for Grant, RSUs granted, net of forfeitures	(796,305)
Options Outstanding, Shares Available for Grant, Granted	(3,038,250)
Options Outstanding, Shares Available for Grant, Canceled	950,840
Options Outstanding, Shares Available for Grant, Ending balance	6,343,313
Options Outstanding, Number of Shares Underlying Options, Beginning balance	9,076,018
Options Outstanding, Number of Shares Underlying Options, Granted	3,038,250
Options Outstanding, Number of Shares Underlying Options, Exercised	(1,314,739)
Options Outstanding, Number of Shares Underlying Options, Canceled	(1,097,127)
Options Outstanding, Number of Shares Underlying Options, Ending balance	9,702,402
Options Outstanding, Number of Shares Underlying Options, Options exercisable	5,846,632
Options Outstanding, Number of Shares Underlying Options, Options vested and expected to vest	9,511,787
Options Outstanding, Weighted-Average Exercise Price, Beginning balance	$ 8.04
Options Outstanding, Weighted-Average Exercise Price, Granted	6.20
Options Outstanding, Weighted-Average Exercise Price, Exercised	1.03
Options Outstanding, Weighted-Average Exercise Price, Canceled	12.51
Options Outstanding, Weighted-Average Exercise Price, Ending balance	7.91
Options Outstanding, Weighted-Average Exercise Price, Options exercisable	7.41
Options Outstanding, Weighted-Average Exercise Price, Options vested and expected to vest	$ 7.91
Options Outstanding, Aggregate Intrinsic Value, Balance	$ 25,683	$ 32,256
Options Outstanding, Aggregate Intrinsic Value, Options exercisable-June 30, 2018	22,042
Options Outstanding, Aggregate Intrinsic Value, Options vested and expected to vest-June 30, 2018	$ 25,514

Equity Incentive Plans - Summ_2

Equity Incentive Plans - Summary of Stock Option Activity (Parenthetical) (Details)	9 Months Ended
	Sep. 30, 2018shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of subject to canceled options excluded	146,287

Equity Incentive Plans - Summ_3

Equity Incentive Plans - Summary of RSU Activity (Details) - Restricted Stock Units (RSUs)	9 Months Ended
	Sep. 30, 2018$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Restricted Stock Units, Beginning balance | shares	1,436,623
Number of Restricted Stock Units, Granted | shares	1,089,450
Number of Restricted Stock Units, Vested | shares	(262,856)
Number of Restricted Stock Units, Canceled/forfeited | shares	(293,145)
Number of Restricted Stock Units, Ending balance | shares	1,970,072
Weighted-Average Grant Date Fair Value Per Share, Beginning balance | $ / shares	$ 11.47
Weighted-Average Grant Date Fair Value Per Share, Granted | $ / shares	6.94
Weighted-Average Grant Date Fair Value Per Share, Vested | $ / shares	12.33
Weighted-Average Grant Date Fair Value Per Share, Canceled/forfeited | $ / shares	11.85
Weighted-Average Grant Date Fair Value Per Share, Ending balance | $ / shares	$ 8.79

Equity Incentive Plans - Summ_4

Equity Incentive Plans - Summary of Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 4,221	$ 4,024	$ 13,472	$ 12,010
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	2,230	2,118	7,514	6,711
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1,991	$ 1,906	$ 5,958	$ 5,299

Equity Incentive Plans - Schedu

Equity Incentive Plans - Schedule of Black-Scholes Option-Pricing Model (Details)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 months	6 months
Volatility	54.50%	65.40%
Risk-free interest rate	2.09%	1.02%
Minimum | Option Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 years 3 months 25 days	5 years 3 months 21 days
Volatility	70.90%	73.20%
Risk-free interest rate	2.38%	1.78%
Maximum | Option Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 18 days	6 years 14 days
Volatility	71.70%	74.10%
Risk-free interest rate	2.89%	2.25%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Contingency [Line Items]
Income tax benefit	$ 385,000	$ 3,874,000	$ 444,000	$ 10,414,000
Current income tax receivable	$ 17,800,000		17,800,000
Amount of claim filed to carryback losses			$ 346,000
State | Earliest Tax Year
Income Tax Contingency [Line Items]
Open tax year			Dec. 31, 2014
State | Latest Tax Year
Income Tax Contingency [Line Items]
Open tax year			Dec. 31, 2017
U.S. Federal Tax Authority | Earliest Tax Year
Income Tax Contingency [Line Items]
Open tax year			Dec. 31, 2014
U.S. Federal Tax Authority | Latest Tax Year
Income Tax Contingency [Line Items]
Open tax year			Dec. 31, 2017
California Tax Authority
Income Tax Contingency [Line Items]
Tax assessment additional period			5 years

Net Loss per Common Share - Sch

Net Loss per Common Share - Schedule of Potentially Dilutive Securities not Included in Calculation of Diluted Per Common Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per common share	11,736,135	10,842,835	11,736,135	10,842,835
Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per common share	9,702,402	9,589,282	9,702,402	9,589,282
Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per common share	1,970,072	1,186,575	1,970,072	1,186,575
Common Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per common share	63,661	66,978	63,661	66,978