Aimmune Therapeutics (AIMT) 10-Q 31 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Aug. 11, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Trading Symbol	AIMT
Entity Registrant Name	AIMMUNE THERAPEUTICS, INC.
Entity Central Index Key	1,631,650
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		42,249,431

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 58,502	$ 2,269
Prepaid expenses	2,105	106
Total current assets	60,607	2,375
Property and equipment, net	1,253	87
Restricted cash	100	40
Other assets	114	29
Total assets	62,074	2,531
Current liabilities:
Accounts payable	309	478
Accrued liabilities	2,796	1,259
Other current liabilities	222	67
Total current liabilities	3,327	1,804
Other liabilities	784	56
Total liabilities	$ 4,111	$ 1,860
Commitments and contingencies (Note 5)
Stockholders’ equity:
Convertible preferred stock
Additional paid-in capital	$ 2,464	$ 1,260
Accumulated deficit	(28,334)	(17,517)
Total stockholders’ equity	57,963	671
Total liabilities and stockholders’ equity	62,074	2,531
Series A Convertible Preferred Stock
Stockholders’ equity:
Convertible preferred stock	4,054	$ 16,928
Series B Convertible Preferred Stock
Stockholders’ equity:
Convertible preferred stock	$ 79,779

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	0
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	50,046,000	32,925,000
Common stock, shares issued	5,698,175	4,252,248
Common stock, shares outstanding	5,698,175	4,252,248
Series A Convertible Preferred Stock
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	13,263,967	13,263,967
Preferred stock, shares issued	11,003,261	13,263,967
Preferred stock, shares outstanding	11,003,261	13,263,967
Preferred stock, liquidation preference	$ 14,071	$ 16,989
Series B Convertible Preferred Stock
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	14,245,550	0
Preferred stock, shares issued	14,047,966	0
Preferred stock, shares outstanding	14,047,966	0
Preferred stock, liquidation preference	$ 80,000	$ 0
Common Stock Subject to Repurchase
Common stock, shares issued	862,673	862,673
Common stock, shares outstanding	788,873	788,873

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Operating expenses
Research and development	$ 3,131	$ 1,801	$ 5,200	$ 3,001
General and administrative	4,246	967	5,618	1,368
Total operating expenses	7,377	2,768	10,818	4,369
Loss from operations	(7,377)	(2,768)	(10,818)	(4,369)
Other income (expense), net
Interest income	1	5	1	12
Net loss and comprehensive loss	$ (7,376)	$ (2,763)	$ (10,817)	$ (4,357)
Net loss per common share, basic and diluted	$ (1.60)	$ (0.94)	$ (2.45)	$ (1.49)
Weighted average shares used in computing net loss per share, basic and diluted	4,618,633	2,926,665	4,422,995	2,926,665

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net loss	$ (10,817,000)	$ (4,357,000)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation	30,000	11,000
Stock-based compensation	989,000	31,000
Changes in operating assets and liabilities:
Prepaid expenses	(563,000)	(558,000)
Other assets	(85,000)
Accounts payable	(169,000)	278,000
Accrued liabilities	1,537,000	315,000
Other	284,000	1,000
Net cash used in operating activities	(8,794,000)	(4,279,000)
Cash flows from investing activities:
Purchase of property and equipment	(596,000)	(44,000)
Restricted cash	(60,000)	(40,000)
Net cash used in investing activities	(656,000)	(84,000)
Cash flows from financing activities:
Net proceeds from issuance of Series B convertible preferred stock, net of issuance costs	79,779,000
Repurchase of Series A convertible preferred stock	(12,874,000)
Net cash proceeds from exercise of stock options, including early exercise	245,000
Offering costs incurred in anticipation of initial public filing	(1,436,000)
Repurchases of common stock subject to early exercise	(31,000)
Net cash provided by financing activities	65,683,000
Net increase (decrease) in cash and cash equivalents	56,233,000	(4,363,000)
Cash and cash equivalents at the beginning of the period	2,269,000	11,951,000
Cash and cash equivalents at the end of the period	58,502,000	$ 7,588,000
Supplemental schedule of non-cash investing and financing activities:
Capital expenditures funded through long term lease obligation	$ 600,000

Formation and Business of the C

Formation and Business of the Company	6 Months Ended
	Jun. 30, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Formation and Business of the Company	1. Formation and Business of the Company Aimmune Therapeutics, Inc. (“Aimmune Therapeutics” or the “Company”), formerly known as Allergen Research Corporation, is a clinical-stage biopharmaceutical company advancing a new therapeutic approach, including the development of proprietary candidates, for the treatment of peanut and other food allergies. The Company is headquartered in Brisbane, California and was incorporated in the state of Delaware on June 24, 2011. In April, 2015 the Company formed a wholly-owned subsidiary in the United Kingdom. Since inception, the Company has incurred net losses and negative cash flows from operations. During the six months ended June 30, 2015, the Company incurred a net loss of $10.8 million and used $8.8 million of cash in operations. At June 30, 2015 the Company had an accumulated deficit of $28.3 million and does not expect to experience positive cash flows in the near future. The Company has financed operations to date primarily through private placements of equity securities. The Company’s ability to continue to meet its obligations and to achieve its business objectives is dependent upon, amongst other things, raising additional capital, obtaining U.S. Food and Drug Administration (“FDA”) and European Medicines Agency (“EMA”) approval and commercializing in the United States and Europe, generating sufficient revenue and its ability to continue to control expenses, if necessary, to meet its obligations as they become due for the foreseeable future. Failure to obtain FDA and EMA approval, commercialize its lead product candidate, manage discretionary expenditures or raise additional financing, as required, may adversely impact the Company’s ability to achieve its intended business objectives. Initial Public Offering On August 5, 2015, the Company’s registration statement on Form S-1 (File No. 333-205501) relating to its initial public offering (“IPO”) of common stock became effective. The IPO closed on August 11, 2015 at which time the Company issued 11,499,999 shares of its common stock at a price of $16 per share, which included 1,499,999 shares sold pursuant to the exercise of the underwriters’ option to purchase additional shares. The Company received approximately $168 million, net of underwriting discounts and commissions, and offering expenses. In addition, upon the Company’s IPO, all outstanding shares of convertible preferred stock converted by their terms into approximately 25.1 million shares of common stock. See Note 6, “Stockholders’ Equity.” Stock Split On July 30, 2015, the Company effected a 1-for-1.317 stock split of the Company’s common stock and convertible preferred stock. The par value of the authorized stock was not adjusted as a result of the stock split. In addition, the Company increased the number of authorized shares of common stock to 55,051,264 and the number of authorized shares of preferred stock to 25,051,264. All issued and outstanding common stock, convertible preferred stock, stock options and per share amounts contained in the accompanying condensed consolidated financial statements and notes to the condensed consolidated financial statements have been retroactively adjusted to give effect to the stock split for all periods presented. In conjunction with the Company’s IPO, the Company filed its amended and restated certificate of incorporation that authorizes 290,000,000 shares of common stock, $0.0001 par value per share, and 10,000,000 shares of preferred stock, $0.0001 par value per share.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Preparation The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial 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, 2014 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 condensed consolidated financial statements have been prepared on the same basis as our 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 our financial information. The results of operations for the three and six months ended June 30, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015 or for any other interim period or for any other future year. The company operates in one reportable segment. 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, 2014 included in our Registration Statement on Form S-1 filed with the SEC. Basis of Consolidation The accompanying condensed consolidated financial statements of the Company include the accounts of its wholly-owned subsidiary. All significant intercompany transactions have been eliminated. Use of Estimates The preparation of the accompanying condensed consolidated financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of costs and expenses during the reporting period. The Company bases its estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis. The Company’s actual results could differ from these estimates under different assumptions or conditions. Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash equivalents. Cash equivalents consist primarily of amounts invested in a bank high yield savings account. Concentration of Credit Risk Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents. The Company’s cash and cash equivalents are held primarily in one large financial institution in the United States. Management believes that this financial institution is financially sound, and accordingly, minimal credit risk exists with respect to this financial institution. The Company is exposed to credit risk in the event of default by the financial institution holding its cash and cash equivalents to the extent recorded on the balance sheets. Fair Value Measurement The carrying amounts of certain financial instruments, including cash and cash equivalents, restricted cash, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities. Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the respective assets. Maintenance and repairs are charged to operations as incurred. Upon sale or retirement of assets, the cost and related accumulated depreciation are removed from the balance sheet and the resulting gain or loss, if any, is reflected in operations. The useful lives of property and equipment are as follows: Furniture and office equipment 4 years Computer equipment 3 years Buildings 25 years Fixtures 10 years Impairment of Long-Lived Assets The Company evaluates its long-lived assets, including property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying value of these assets may not be recoverable. Recoverability of these assets is measured by comparison of the carrying amount of each asset to the future undiscounted cash flows expected to result from the use of the asset and its eventual disposition. If the asset is considered to be impaired, the amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired assets. The Company has not recorded impairment of any long-lived assets in the periods presented. Leases The Company entered into lease agreements for its corporate headquarters and research facility in San Mateo, California through July 2017. In March 2015, the Company entered into a new lease for its corporate headquarters and research facility in Brisbane, California. In May 2015, the Company ceased use of its San Mateo facility and moved into its new facility. These leases are classified as operating leases. Rent expense is recognized on a straight-line basis over the terms of the leases and, accordingly, the Company records the difference between cash rent payments and the recognition of rent expense as a deferred rent liability. Incentives granted under the Company’s facilities leases are deferred and recognized as adjustments to rental expense on a straight-line basis over the term of the lease. In June 2015, the Company signed a new facility lease for a manufacturing facility in Clearwater, Florida. The Company was considered the deemed owner for accounting purposes. See Note 5, “Commitments and Contingencies.” Research and Development The Company expenses research and development costs as incurred. The Company records accrued liabilities for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of pre-clinical studies and clinical trials and contract manufacturing activities. These costs are a significant component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers under the service agreements. The Company makes significant judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed, number of patients enrolled and the rate of patient enrollments may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations. Stock-based Compensation Stock-based awards issued to employees, including stock options, are measured at fair value on the grant date using the Black-Scholes option-pricing model and recognized as expense on a straight-line basis over the employee’s requisite service period (generally the vesting period). Because noncash stock compensation expense is based on awards ultimately expected to vest, it is reduced by an estimate for future forfeitures. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from estimates. There were 2,690,230 and 0 stock options granted during the six months ended June 30, 2015 and 2014, respectively. Income Taxes The Company uses the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the tax bases of reported assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The Company must then assess the likelihood that the resulting deferred tax assets will be realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. Due to the Company’s lack of earnings history, the net deferred tax assets have been fully offset by a valuation allowance. The Company has adopted Financial Accounted Standards Board Accounting Standards Codification 740, Income Taxes, regarding how uncertain tax positions should be recognized, measured, presented, and disclosed in the financial statements. As of June 30, 2015 and Comprehensive Income or Loss Comprehensive income or loss is defined as the change in equity during a period from transactions and other events, excluding changes resulting from investments from owners and distributions to owners. The Company currently has no components of Comprehensive Income or Loss other than net income, therefore no separate statement of comprehensive income is presented. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board, or FASB, issued Auditing Standards Update, or ASU, No. 2014-09, Revenue from Contracts with Customers (Topic 606) In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2015
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 and accounts payable approximated 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 provide 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 to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The accounting guidance 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 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): June 30, 2015 (unaudited) Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 58,502 $ — $ — $ 58,502 December 31, 2014 Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 2,269 $ — $ — $ 2,269

Balance Sheet Components

Balance Sheet Components	6 Months Ended
	Jun. 30, 2015
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Components	4. Balance Sheet Components Property and Equipment, Net Property and equipment, net consists of the following (in thousands): June 30, December (unaudited) Furniture and equipment $ 222 $ 58 Computer equipment 162 67 Construction in progress 937 — Property and equipment, gross 1,321 125 Less: accumulated depreciation (68 ) (38 ) Property and equipment, net $ 1,253 $ 87 Depreciation expense for the three months ended June 30, 2015 and 2014 was $19,000 and $6,000, respectively, and for the six months ended June 30, 2015 and 2014, was $30,000 and $11,000 , respectively. Accrued Liabilities Accrued liabilities consisted of the following (in thousands): June 30, 2015 December (unaudited) Compensation and benefits $ 496 $ 645 Research and development 454 542 Professional and consulting 1,846 71 Other — 1 Total $ 2,796 $ 1,259 As of June 30, 2015, approximately $1,436,000 of accrued liabilities for professional and consulting was related to the Company’s initial public offering.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2015
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	5. Commitments and Contingencies Facility Leases In July 2013, the Company entered into a 48-month lease for its corporate headquarters and research facility in San Mateo, California. In July 2014, the Company entered into a second lease that expanded the space and was for a term of 36 months beginning in July 2014 and coterminous with the first lease. Under both leases, the Company paid base rent plus the tenant’s proportionate share of estimated basic operating cost as defined in the leases. The leases required a $25,000 security deposit for the duration of the leases. Rent expense under operating leases for the three months ended June 30, 2015 and and $24,000, and $49,000, term New Facility Leases In March 2015, the Company signed a new facility lease for its corporate headquarters and research facility in Brisbane, California. The new lease, which has been classified as an operating lease, commenced on May 1, 2015 with an initial term of 51 months. The Company has the right to extend the lease term for an additional 3 years at the greater of the then current base rent or the then prevailing market rent, as defined by the Renewal Option contained in the lease. The agreement required a security deposit of $85,000. The new lease calls for future aggregate minimum noncancelable lease payments as of May 1, 2015 (the inception of the lease) as follows (in thousands): Year Ended December 31, 2015 $ 190 2016 464 2017 478 2018 492 and after 294 Total $ 1,918 The Company is responsible for operating expenses over base operating expenses as defined in the headquarters lease agreement. In June 2015, the Company signed a new facility lease for a manufacturing facility in Clearwater, Florida. The initial term is Year Ended December 31, 2015 $ 38 2016 151 2017 156 2018 160 and after 1,198 Total $ 1,703 The Company is responsible for operating expenses including real estate taxes as defined in the manufacturing facility lease agreement. Purchase Commitments The Company purchases peanut flour, the source material for AR101, from the Golden Peanut Company pursuant to a long term exclusive commercial supply agreement. Pursuant to the agreement, the Company’s purchase obligation commences with the first delivery of peanut flour for commercial use, which it currently anticipates will not occur prior to 2018. Assuming the Company starts its purchase obligation of peanut flour for commercial use in 2018, which is not assured, the aggregate purchase commitment under this agreement is $1.2 million over a term of five years. Indemnifications The Company indemnifies each of its officers and directors for certain events or occurrences, subject to certain limits, while the officer or director is or was serving at the Company’s request in such capacity, as permitted under Delaware law and in accordance with its certificate of incorporation and bylaws. The term of the indemnification period lasts as long as an officer or a director may be subject to any proceeding arising out of acts or omissions of such officer or director in such capacity. The maximum amount of potential future indemnification is unlimited; however, the Company currently holds director and officer liability insurance. This insurance allows the transfer of risk associated with the Company’s exposure and may enable it to recover a portion of any future amounts paid. The Company believes that the fair value of these indemnification obligations is minimal. Accordingly, it has not recognized any liabilities relating to these obligations for any period. Legal During the normal course of business, the Company may be a party to legal claims that may not be covered by insurance. Management does not believe that any such claims would have a material impact on the Company’s consolidated financial statements.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Shareholders' Equity	6. Stockholders’ Equity Initial Public Offering On August 11, 2015, the Company completed its IPO, in which it sold 11,499,999 shares of common stock at a price to the public of $16 per share, raising approximately $168 million in total net proceeds to the Company. Upon the consummation of the IPO, all outstanding shares of convertible preferred stock were converted into approximately 25.1 million shares of common stock. The following table sets forth the Company’s stockholder’s equity as of June 30, 2015 on a pro forma basis to give effect to the convertible preferred stock and on a pro forma as adjusted basis to give further effect to the sale of 11,499,999 shares of common stock in the IPO at the initial public offering price of $16.00 per share, after deducting the underwriting discounts and commissions and estimated offering expenses payable by the Company: As of June 30, 2015 Actual Pro Forma Pro Forma As Adjusted Stockholders’ equity: Series A convertible preferred stock, par value $0.0001 per share—13,263,967 shares authorized as of June 30, 2015; 11,003,261 shares issued and outstanding actual; no shares authorized, issued and outstanding, pro forma and pro forma as adjusted 4,054 — — Series B convertible preferred stock, par value $0.0001 per share—no and 14,245,550 shares authorized as of June 30, 2015; 14,047,966 shares issued and outstanding, actual; no shares authorized, issued and outstanding, pro forma and pro forma as adjusted 79,779 — — Preferred stock, par value $0.0001 per share, no shares authorized, issued and outstanding, actual; 10,000,000 shares authorized, no shares issued and outstanding, pro forma and pro forma as adjusted — — — Common stock, par value $0.0001 per share—50,046,000 shares authorized, 5,698,175 shares issued and outstanding, actual; 290,000,000 shares authorized, 30,749,432 shares issued and outstanding, pro forma, and 290,000,000 shares authorized, 42,249,431 shares issued and outstanding, pro forma as adjusted — 3 4 Additional paid in capital 2,464 86,294 253,913 Accumulated deficit (28,334 ) (28,334 ) (28,334 ) Total stockholders’ equity 57,963 57,963 225,583

Stock-based Awards

Stock-based Awards	6 Months Ended
	Jun. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based Awards	7. Stock-based Awards In January 2013, the Company adopted its Stock Plan (the “Plan”). Under the Plan, shares of the Company’s common stock have been reserved for the issuance of stock options and restricted stock to employees, directors, and consultants under terms and provisions established by the Board of Directors and approved by the Company’s stockholders. At June 30, 2015 and and 639,625 and th th The Plan allows employees to exercise a stock option in exchange for stock before the requisite service is provided (e.g., before the award is vested under its original terms); however, such arrangements permit the Company to subsequently repurchase such shares at the exercise price if the vesting conditions are not satisfied. Such an exercise is not substantive for accounting purposes. Therefore, the payment received by the Company for the exercise price is recognized as an early exercise liability on the balance sheets and will be transferred to common stock and additional paid-in capital as such shares vest. At June 30, 2015 and Activity under the Plan is set forth below: Options Outstanding Shares Available for Grant Number and Unvested Shares Weighted- Average Exercise Price Weighted Average Remaining Contractual Life (in years) Balance, December 31, 2014 639,625 2,566,559 $ 0.14 9.19 Additional shares authorized 3,226,650 Options granted (2,690,230 ) 2,690,230 $ 3.02 Options exercised and shares vested (1,372,129 ) $ 0.14 Options repurchased 211,793 (211,793 ) $ 0.14 Options cancelled — — Balances – June 30, 2015 1,387,838 3,672,867 $ 2.25 9.75 Options vested and expected to vest as of June 30, 2015 (unaudited) 3,328,871 $ 1.61 9.51 Options exercisable as of June 30, 2015 (unaudited) 2,810,912 $ 2.83 9.75 The aggregate intrinsic values of options outstanding, exercisable, and vested and expected to vest were calculated as the difference between the exercise price of the options and the estimated value of the Company common stock as determined by the Company’s Board of Directors as of December 31, 2014. The Plan provides for early exercise, therefore, all the Company’s outstanding stock options are exercisable. Stock Options Granted to Employees The Company did not issue any stock options during the three and six months ended June 30, 2014. Stock options granted during the three months and six months ended June 30, 2015 had a weighted-average grant-date fair value of $4.81. The fair value is being expensed over the vesting period of the options, which is either four years or two years on a straight-line basis as the services are being provided. No tax benefits were realized from options during the periods. As of June 30, 2015 and and $120,000, The fair value of employee stock options was estimated using the Black-Scholes pricing model, with the following weighted-average assumptions (unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Expected volatility 75.77 % N/A 75.77 % N/A Risk free interest rate 1.69 % N/A 1.69 % N/A Divided yield — N/A — N/A Expected term (in years) 6.00 N/A 6.00 N/A Determining Fair Value of Stock Options The fair value of each grant of stock options was determined by the Company using the methods and assumptions discussed below. The determination of each of these inputs is subjective and generally requires significant judgment. Expected volatility —The expected stock price volatility assumption was determined by examining the historical volatilities of a group of industry peers, as the Company did not have any trading history for the Company’s common stock. The Company will continue to analyze the historical stock price volatility and expected term assumptions as more historical data for the Company’s common stock becomes available. Expected term —The expected term of stock options represents the weighted average period the stock options are expected to be outstanding. The Company’s option grants are considered “plain vanilla.” Therefore, the Company has opted to use the simplified method for estimating the expected term as provided by the Securities and Exchange Commission. The simplified method calculates the expected term as the average time- to-vesting and the contractual life of the options. Expected dividend —The expected dividend assumption was based on the Company’s history and expectation that it will not declare dividend payout for the near future. Risk-free interest rate —The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected terms. Fair value of common stock —The fair value of the shares of common stock underlying the stock options has historically been the responsibility of and determined by the Company’s board of directors. Because there has been no public market for the Company’s common stock, the board of directors determined fair value of common stock at the time of grant of the option by considering a number of objective and subjective factors including independent third-party valuations of the Company’s common stock, sales of convertible preferred stock to unrelated third parties, operating and financial performance, the lack of liquidity of capital stock and general and industry specific economic outlook, amongst other factors. The fair value of the underlying common stock will be determined by the Company’s board of directors until such time as the Company’s common stock is listed on an established exchange or national market system. For grants during the three months ended June 30, 2015, the Company utilized a higher fair market value, for which the increase was attributed to an increased likelihood of a public offering during the period. Stock-based compensation expense, net of estimated forfeitures, is reflected in the statements of operations (in thousands, unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Research and development $ 88 $ 4 $ 96 $ 9 General and administrative 875 11 893 22 Total stock-based compensation expense $ 963 $ 15 $ 989 $ 31 During the three and six months ended June 30, 2015, the Company recorded approximately $562,000 of stock compensation expense related to the acceleration of certain former executives’ stock options.

Net Loss per Share

Net Loss per Share	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Net Loss per Share	8. Net Loss per Share The following table sets forth the computation of the Company’s basic and diluted net loss per share during the three months and six months periods ended June 30, 2015 and 2014 (in thousands, except share and per share data, unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Numerator: Net loss $ (7,376 ) $ (2,763 ) $ (10,817 ) $ (4,357 ) Denominator: Shares used in computing net loss per share, basic and diluted 4,618,633 2,926,665 4,422,995 2,926,665 Net loss per share basic and diluted $ (1.60 ) $ (0.94 ) $ (2.45 ) $ (1.49 ) The following common stock equivalents were excluded from the computation of diluted net loss per share for the periods presented because including them would have been antidilutive (unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Convertible preferred stock 25,051,257 13,263,967 21,713,994 13,263,967 Stock options 1,942,218 2,247,212 3,672,867 2,247,212

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2015
Subsequent Events [Abstract]
Subsequent Events	9. Subsequent Events Income Taxes In July 2015, the Company formed a wholly-owned foreign subsidiary to which the Company licensed certain intangible rights. The Company expects that 2015 recognized revenue in the U.S., if any, as a result of this transaction will be fully offset by prior year NOLs and current year expenses. For US tax purposes, the Company expects to recognize revenue from the license in future years, in the form of royalties, if any are received in such years. Stock-based Compensation In July 2015, the Company adopted a new stock plan (“the 2015 Plan”). Under the 2015 plan, shares Facility Lease Amendment In August 2015, the Company entered into an amendment for its existing corporate headquarters and research facility in Brisbane, California. Pursuant to the amendment, the Company will lease additional office space. The term for the new space is 72 months from the delivery of the premises to the Company, which is expected to occur near the end of 2015. In addition, the term of the existing office space has been extended so that it is coterminous with the new space. As of the commencement of the amendment, future aggregate minimum lease payments for the combined space are as follows (in thousands): Year ended December 31, 2015 $ 190 2016 1,010 2017 1,602 2018 1,650 and after 5,265 Total $ 9,717 The Company is responsible for operating expenses over base operating expenses as defined in the headquarters lease agreement.

Summary of Significant Accoun15

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Basis of Preparation	Basis of Preparation The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial 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, 2014 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 condensed consolidated financial statements have been prepared on the same basis as our 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 our financial information. The results of operations for the three and six months ended June 30, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015 or for any other interim period or for any other future year. The company operates in one reportable segment. 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, 2014 included in our Registration Statement on Form S-1 filed with the SEC.
Basis of Consolidation	Basis of Consolidation The accompanying condensed consolidated financial statements of the Company include the accounts of its wholly-owned subsidiary. All significant intercompany transactions have been eliminated.
Use of Estimates	Use of Estimates The preparation of the accompanying condensed consolidated financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of costs and expenses during the reporting period. The Company bases its estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis. The Company’s actual results could differ from these estimates under different assumptions or conditions.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash equivalents. Cash equivalents consist primarily of amounts invested in a bank high yield savings account.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents. The Company’s cash and cash equivalents are held primarily in one large financial institution in the United States. Management believes that this financial institution is financially sound, and accordingly, minimal credit risk exists with respect to this financial institution. The Company is exposed to credit risk in the event of default by the financial institution holding its cash and cash equivalents to the extent recorded on the balance sheets.
Fair Value Measurement	Fair Value Measurement The carrying amounts of certain financial instruments, including cash and cash equivalents, restricted cash, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities.
Property and Equipment	Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the respective assets. Maintenance and repairs are charged to operations as incurred. Upon sale or retirement of assets, the cost and related accumulated depreciation are removed from the balance sheet and the resulting gain or loss, if any, is reflected in operations. The useful lives of property and equipment are as follows: Furniture and office equipment 4 years Computer equipment 3 years Buildings 25 years Fixtures 10 years
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates its long-lived assets, including property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying value of these assets may not be recoverable. Recoverability of these assets is measured by comparison of the carrying amount of each asset to the future undiscounted cash flows expected to result from the use of the asset and its eventual disposition. If the asset is considered to be impaired, the amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired assets. The Company has not recorded impairment of any long-lived assets in the periods presented.
Leases	Leases The Company entered into lease agreements for its corporate headquarters and research facility in San Mateo, California through July 2017. In March 2015, the Company entered into a new lease for its corporate headquarters and research facility in Brisbane, California. In May 2015, the Company ceased use of its San Mateo facility and moved into its new facility. These leases are classified as operating leases. Rent expense is recognized on a straight-line basis over the terms of the leases and, accordingly, the Company records the difference between cash rent payments and the recognition of rent expense as a deferred rent liability. Incentives granted under the Company’s facilities leases are deferred and recognized as adjustments to rental expense on a straight-line basis over the term of the lease. In June 2015, the Company signed a new facility lease for a manufacturing facility in Clearwater, Florida. The Company was considered the deemed owner for accounting purposes. See Note 5, “Commitments and Contingencies.”
Research and Development	Research and Development The Company expenses research and development costs as incurred. The Company records accrued liabilities for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of pre-clinical studies and clinical trials and contract manufacturing activities. These costs are a significant component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers under the service agreements. The Company makes significant judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed, number of patients enrolled and the rate of patient enrollments may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations.
Stock-based Compensation	Stock-based Compensation Stock-based awards issued to employees, including stock options, are measured at fair value on the grant date using the Black-Scholes option-pricing model and recognized as expense on a straight-line basis over the employee’s requisite service period (generally the vesting period). Because noncash stock compensation expense is based on awards ultimately expected to vest, it is reduced by an estimate for future forfeitures. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from estimates. There were 2,690,230 and 0 stock options granted during the six months ended June 30, 2015 and 2014, respectively.
Income Taxes	Income Taxes The Company uses the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the tax bases of reported assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The Company must then assess the likelihood that the resulting deferred tax assets will be realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. Due to the Company’s lack of earnings history, the net deferred tax assets have been fully offset by a valuation allowance. The Company has adopted Financial Accounted Standards Board Accounting Standards Codification 740, Income Taxes, regarding how uncertain tax positions should be recognized, measured, presented, and disclosed in the financial statements. As of June 30, 2015 and
Comprehensive Income or Loss	Comprehensive Income or Loss Comprehensive income or loss is defined as the change in equity during a period from transactions and other events, excluding changes resulting from investments from owners and distributions to owners. The Company currently has no components of Comprehensive Income or Loss other than net income, therefore no separate statement of comprehensive income is presented.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board, or FASB, issued Auditing Standards Update, or ASU, No. 2014-09, Revenue from Contracts with Customers (Topic 606) In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.

Summary of Significant Accoun16

Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Schedule of Useful Lives of Property and Equipment	The useful lives of property and equipment are as follows: Furniture and office equipment 4 years Computer equipment 3 years Buildings 25 years Fixtures 10 years

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Summary of Financial Instruments 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): June 30, 2015 (unaudited) Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 58,502 $ — $ — $ 58,502 December 31, 2014 Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 2,269 $ — $ — $ 2,269

Balance Sheet Components (Table

Balance Sheet Components (Tables)	6 Months Ended
	Jun. 30, 2015
Balance Sheet Related Disclosures [Abstract]
Summary of Property And Equipment, Net	Property and equipment, net consists of the following (in thousands): June 30, December (unaudited) Furniture and equipment $ 222 $ 58 Computer equipment 162 67 Construction in progress 937 — Property and equipment, gross 1,321 125 Less: accumulated depreciation (68 ) (38 ) Property and equipment, net $ 1,253 $ 87
Summary of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): June 30, 2015 December (unaudited) Compensation and benefits $ 496 $ 645 Research and development 454 542 Professional and consulting 1,846 71 Other — 1 Total $ 2,796 $ 1,259

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2015
Headquarters
Schedule of Future Aggregate Minimum Lease Payments	The new lease calls for future aggregate minimum noncancelable lease payments as of May 1, 2015 (the inception of the lease) as follows (in thousands): Year Ended December 31, 2015 $ 190 2016 464 2017 478 2018 492 and after 294 Total $ 1,918
Manufacturing Facility
Schedule of Future Aggregate Minimum Lease Payments	The new lease calls for future aggregate minimum lease payments as of the commencement of the lease as follows (in thousands): Year Ended December 31, 2015 $ 38 2016 151 2017 156 2018 160 and after 1,198 Total $ 1,703

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Schedule of Company's Stockholder's Equity	The following table sets forth the Company’s stockholder’s equity as of June 30, 2015 on a pro forma basis to give effect to the convertible preferred stock and on a pro forma as adjusted basis to give further effect to the sale of 11,499,999 shares of common stock in the IPO at the initial public offering price of $16.00 per share, after deducting the underwriting discounts and commissions and estimated offering expenses payable by the Company: As of June 30, 2015 Actual Pro Forma Pro Forma As Adjusted Stockholders’ equity: Series A convertible preferred stock, par value $0.0001 per share—13,263,967 shares authorized as of June 30, 2015; 11,003,261 shares issued and outstanding actual; no shares authorized, issued and outstanding, pro forma and pro forma as adjusted 4,054 — — Series B convertible preferred stock, par value $0.0001 per share—no and 14,245,550 shares authorized as of June 30, 2015; 14,047,966 shares issued and outstanding, actual; no shares authorized, issued and outstanding, pro forma and pro forma as adjusted 79,779 — — Preferred stock, par value $0.0001 per share, no shares authorized, issued and outstanding, actual; 10,000,000 shares authorized, no shares issued and outstanding, pro forma and pro forma as adjusted — — — Common stock, par value $0.0001 per share—50,046,000 shares authorized, 5,698,175 shares issued and outstanding, actual; 290,000,000 shares authorized, 30,749,432 shares issued and outstanding, pro forma, and 290,000,000 shares authorized, 42,249,431 shares issued and outstanding, pro forma as adjusted — 3 4 Additional paid in capital 2,464 86,294 253,913 Accumulated deficit (28,334 ) (28,334 ) (28,334 ) Total stockholders’ equity 57,963 57,963 225,583

Stock-based Awards (Tables)

Stock-based Awards (Tables)	6 Months Ended
	Jun. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity	Activity under the Plan is set forth below: Options Outstanding Shares Available for Grant Number and Unvested Shares Weighted- Average Exercise Price Weighted Average Remaining Contractual Life (in years) Balance, December 31, 2014 639,625 2,566,559 $ 0.14 9.19 Additional shares authorized 3,226,650 Options granted (2,690,230 ) 2,690,230 $ 3.02 Options exercised and shares vested (1,372,129 ) $ 0.14 Options repurchased 211,793 (211,793 ) $ 0.14 Options cancelled — — Balances – June 30, 2015 1,387,838 3,672,867 $ 2.25 9.75 Options vested and expected to vest as of June 30, 2015 (unaudited) 3,328,871 $ 1.61 9.51 Options exercisable as of June 30, 2015 (unaudited) 2,810,912 $ 2.83 9.75
Schedule of Fair Value of Employee Stock Options Estimated with Weighted-Average Assumptions	The fair value of employee stock options was estimated using the Black-Scholes pricing model, with the following weighted-average assumptions (unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Expected volatility 75.77 % N/A 75.77 % N/A Risk free interest rate 1.69 % N/A 1.69 % N/A Divided yield — N/A — N/A Expected term (in years) 6.00 N/A 6.00 N/A
Summary of Stock-based Compensation Expense Net of Estimated Forfeitures	Stock-based compensation expense, net of estimated forfeitures, is reflected in the statements of operations (in thousands, unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Research and development $ 88 $ 4 $ 96 $ 9 General and administrative 875 11 893 22 Total stock-based compensation expense $ 963 $ 15 $ 989 $ 31

Net Loss per Share (Tables)

Net Loss per Share (Tables)	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Computation of Basic and Diluted Net loss Per Share	The following table sets forth the computation of the Company’s basic and diluted net loss per share during the three months and six months periods ended June 30, 2015 and 2014 (in thousands, except share and per share data, unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Numerator: Net loss $ (7,376 ) $ (2,763 ) $ (10,817 ) $ (4,357 ) Denominator: Shares used in computing net loss per share, basic and diluted 4,618,633 2,926,665 4,422,995 2,926,665 Net loss per share basic and diluted $ (1.60 ) $ (0.94 ) $ (2.45 ) $ (1.49 )
Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss per Share	The following common stock equivalents were excluded from the computation of diluted net loss per share for the periods presented because including them would have been antidilutive (unaudited): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Convertible preferred stock 25,051,257 13,263,967 21,713,994 13,263,967 Stock options 1,942,218 2,247,212 3,672,867 2,247,212

Subsequent Events (Tables)

Subsequent Events (Tables)	6 Months Ended
	Jun. 30, 2015
Corporate Headquarters and Research Facility
Schedule of Future Aggregate Minimum Lease Payments	As of the commencement of the amendment , future aggregate minimum lease payments for the combined space are as follows (in thousands): Year ended December 31, 2015 $ 190 2016 1,010 2017 1,602 2018 1,650 and after 5,265 Total $ 9,717

Formation and Business of the24

Formation and Business of the Company - Additional Information (Details) $ / shares in Units, $ in Thousands	Aug. 11, 2015USD ($)$ / sharesshares	Jul. 30, 2015shares	Jun. 30, 2015USD ($)$ / sharesshares	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)$ / sharesshares	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)$ / sharesshares
Organization And Description Of Business [Line Items]
Net loss | $			$ 7,376	$ 2,763	$ 10,817	$ 4,357
Net cash used in operating activities | $					8,794	$ 4,279
Accumulated deficit | $			$ 28,334		$ 28,334		$ 17,517
Common stock, shares authorized			50,046,000		50,046,000		32,925,000
Preferred stock, shares authorized			0		0
Common stock, par value | $ / shares			$ 0.0001		$ 0.0001		$ 0.0001
Preferred stock, par value | $ / shares			$ 0.0001		$ 0.0001
Subsequent Event
Organization And Description Of Business [Line Items]
Proceeds from initial public offering, net of underwriting discount and commissions | $	$ 168,000
Description of stock split		On July 30, 2015, the Company effected a 1-for-1.317 stock split of the Company’s common stock and convertible preferred stock.
Stock split conversion ratio		0.7593
Common stock, shares authorized		55,051,264
Preferred stock, shares authorized		25,051,264
Subsequent Event | IPO
Organization And Description Of Business [Line Items]
Common stock, shares issued	11,499,999
Common stock issued price per share | $ / shares	$ 16
Shares issued pursuant to exercise of underwriters' option	1,499,999
Outstanding shares of convertible preferred stock converted into common stock	25,100,000
Common stock, shares authorized	290,000,000
Preferred stock, shares authorized	10,000,000
Common stock, par value | $ / shares	$ 0.0001
Preferred stock, par value | $ / shares	$ 0.0001

Summary of Significant Accoun25

Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)Segmentshares	Jun. 30, 2014USD ($)shares	Dec. 31, 2014USD ($)
Accounting Policies [Abstract]
Number of reportable segments | Segment			1
Impairment of any long lived assets	$ 0	$ 0	$ 0	$ 0
Stock options granted | shares			2,690,230	0
Unrecognized tax benefits	$ 0		$ 0		$ 0

Summary of Significant Accoun26

Summary of Significant Accounting Policies - Schedule of Useful Lives of Property and Equipment (Details)	6 Months Ended
	Jun. 30, 2015
Furniture And Office Equipment
Property Plant And Equipment [Line Items]
Useful lives of property and equipment	4 years
Computer Equipment
Property Plant And Equipment [Line Items]
Useful lives of property and equipment	3 years
Buildings
Property Plant And Equipment [Line Items]
Useful lives of property and equipment	25 years
Fixtures
Property Plant And Equipment [Line Items]
Useful lives of property and equipment	10 years

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 58,502	$ 2,269
Level 1
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 58,502	$ 2,269

Balance Sheet Components - Summ

Balance Sheet Components - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,321	$ 125
Less: accumulated depreciation	(68)	(38)
Property and equipment, net	1,253	87
Furniture and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	222	58
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	162	$ 67
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 937

Balance Sheet Components - Addi

Balance Sheet Components - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Balance Sheet Components [Line Items]
Depreciation	$ 19,000	$ 6,000	$ 30,000	$ 11,000
Accrued liabilities of professional and consulting	1,846,000		1,846,000		$ 71,000
Initial Public Offering
Balance Sheet Components [Line Items]
Accrued liabilities of professional and consulting	$ 1,436,000		$ 1,436,000

Balance Sheet Components - Su30

Balance Sheet Components - Summary of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Accrued Liabilities Current [Abstract]
Compensation and benefits	$ 496	$ 645
Research and development	454	542
Professional and consulting	1,846	71
Other		1
Total	$ 2,796	$ 1,259

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	May. 01, 2015	Jun. 30, 2015	Jul. 31, 2014	Jul. 31, 2013	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	May. 31, 2015
Commitments And Contingencies [Line Items]
Long-term purchase commitment amount							$ 1,200,000
Long-term purchase commitment period							5 years
Facility Leases
Commitments And Contingencies [Line Items]
Term of lease for corporate headquarters			36 months	48 months
Security deposit				$ 25,000
Rent expense under operating leases					$ 214,000	$ 24,000	$ 255,000	$ 49,000
Accrued liabilities									$ 121,000
New Facilities Leases
Commitments And Contingencies [Line Items]
Term of lease for corporate headquarters	51 months	120 months
Security deposit	$ 85,000	$ 35,000			35,000		35,000
Lease term	3 years
Design costs related to building							90,000
Construction in progress for costs incurred by the lessor		$ 600,000			$ 600,000		$ 600,000

Commitments and Contingencies32

Commitments and Contingencies - Future Aggregate Minimum Lease Payments (Details) $ in Thousands	Jun. 30, 2015USD ($)
Headquarters
Operating Leased Assets [Line Items]
2,015	$ 190
2,016	464
2,017	478
2,018	492
and after	294
Total	1,918
Manufacturing Facility
Operating Leased Assets [Line Items]
2,015	38
2,016	151
2,017	156
2,018	160
and after	1,198
Total	$ 1,703

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - Aug. 11, 2015 - Subsequent Event - USD ($) $ / shares in Units, $ in Millions	Total
Class Of Stock [Line Items]
Net proceeds from initial public offering	$ 168
Initial Public Offering
Class Of Stock [Line Items]
Common stock, shares issued	11,499,999
Common stock issued price per share	$ 16
Outstanding shares of convertible preferred stock converted into common stock	25,100,000

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Company's Stockholder's Equity (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Stockholders’ equity:
Preferred stock
Additional paid in capital	$ 2,464	$ 1,260
Accumulated deficit	(28,334)	(17,517)
Total stockholders’ equity	$ 57,963	671
Pro Forma
Stockholders’ equity:
Preferred stock
Common stock, par value $0.0001 per share—50,046,000 and 32,925,000 shares authorized as of June 30, 2015 (unaudited) and December 31, 2014, respectively; 5,698,175 and 4,252,248 shares issued and outstanding as of June 30, 2015 (unaudited) and December 31, 2014, respectively (including 862,673 and 788,873 shares subject to repurchase, legally issued and outstanding as of June 30, 2015 (unaudited) and December 31, 2014, respectively)	$ 3
Additional paid in capital	86,294
Accumulated deficit	(28,334)
Total stockholders’ equity	$ 57,963
Pro Forma As Adjusted
Stockholders’ equity:
Preferred stock
Common stock, par value $0.0001 per share—50,046,000 and 32,925,000 shares authorized as of June 30, 2015 (unaudited) and December 31, 2014, respectively; 5,698,175 and 4,252,248 shares issued and outstanding as of June 30, 2015 (unaudited) and December 31, 2014, respectively (including 862,673 and 788,873 shares subject to repurchase, legally issued and outstanding as of June 30, 2015 (unaudited) and December 31, 2014, respectively)	$ 4
Additional paid in capital	253,913
Accumulated deficit	(28,334)
Total stockholders’ equity	225,583
Series A Convertible Preferred Stock
Stockholders’ equity:
Preferred stock	4,054	$ 16,928
Series B Convertible Preferred Stock
Stockholders’ equity:
Preferred stock	$ 79,779

Stockholders' Equity - Schedu35

Stockholders' Equity - Schedule of Company's Stockholder's Equity (Parenthetical) (Details) - $ / shares	Jun. 30, 2015	Dec. 31, 2014
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	0
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	50,046,000	32,925,000
Common stock, shares issued	5,698,175	4,252,248
Common stock, shares outstanding	5,698,175	4,252,248
Pro Forma
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	10,000,000
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Common stock, par value	$ 0.0001
Common stock, shares authorized	290,000,000
Common stock, shares issued	30,749,432
Common stock, shares outstanding	30,749,432
Pro Forma As Adjusted
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	10,000,000
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Common stock, par value	$ 0.0001
Common stock, shares authorized	290,000,000
Common stock, shares issued	42,249,431
Common stock, shares outstanding	42,249,431
Series A Convertible Preferred Stock
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	13,263,967	13,263,967
Preferred stock, shares issued	11,003,261	13,263,967
Preferred stock, shares outstanding	11,003,261	13,263,967
Series A Convertible Preferred Stock | Pro Forma
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	0
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Series A Convertible Preferred Stock | Pro Forma As Adjusted
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	0
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Series B Convertible Preferred Stock
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	14,245,550	0
Preferred stock, shares issued	14,047,966	0
Preferred stock, shares outstanding	14,047,966	0
Series B Convertible Preferred Stock | Pro Forma
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	0
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Series B Convertible Preferred Stock | Pro Forma As Adjusted
Class Of Stock [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	0
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0

Stock-based Awards - Additional

Stock-based Awards - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
	Jan. 31, 2013	Jun. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		1,387,838	1,387,838	639,625
Unvested shares outstanding		3,672,867	3,672,867	2,566,559
Former Executive
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Accelerated stock compensation expense		$ 562,000	$ 562,000
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted, weighted average grant-date fair value		$ 4.81	$ 4.81
Tax benefit realized from option			$ 0
Unrecognized employee stock-based compensation		$ 5,670,000	$ 5,670,000	$ 120,000
Expected recognized over weighted-average remaining vesting period			3 years 6 months 26 days	2 years 5 months 5 days
Maximum | Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period			4 years
Minimum | Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period			2 years
January 2013 Stock Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		1,387,838	1,387,838	639,625
Minimum percentage of voting rights of all classes of stock	10.00%
Percentage of statutory stock options	110.00%
Options expiration period	10 years
Unvested shares issued		862,673	862,673	788,873
Unvested shares outstanding		862,673	862,673	788,873
Exercise liability		$ 309,000	$ 309,000
Exercise liability current		158,000	158,000
Exercise liability non current		$ 151,000	$ 151,000
January 2013 Stock Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options expiration period	10 years
January 2013 Stock Plan | First Anniversary
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	4 years
Option vesting rights, percentage	25.00%
January 2013 Stock Plan | Thereafter
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option vesting rights, percentage	2.08%
January 2013 Stock Plan | Over Two Years
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	2 years
Option vesting rights, percentage	4.17%

Stock-based Awards - Summary of

Stock-based Awards - Summary of Stock Option Activity (Details) - $ / shares	6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Shares Available for Grant
Shares Available for Grant, Beginning Balance	639,625
Shares Available for Grant, Additional shares authorized	3,226,650
Shares Available for Grant, Options granted	(2,690,230)	0
Shares Available for Grant, Options repurchased	211,793
Shares Available for Grant, Ending Balance	1,387,838		639,625
Number of Options and Unvested Shares
Number of Options and Unvested Shares, Beginning Balance	2,566,559
Number of Options and Unvested Shares, Options granted	2,690,230	0
Number of Options and Unvested Shares, Options exercised and shares vested	(1,372,129)
Number of Options and Unvested Shares, Options repurchased	(211,793)
Number of Options and Unvested Shares, Ending Balance	3,672,867		2,566,559
Number of Options and Unvested Shares, Options vested and expected to vest as of June 30, 2015 (unaudited)	3,328,871
Number of Options and Unvested Shares, Options exercisable as of June 30, 2015 (unaudited)	2,810,912
Weighted-Average Exercise Price
Weighted-Average Exercise Price, Beginning Balance	$ 0.14
Weighted-Average Exercise Price, Options granted	3.02
Weighted-Average Exercise Price, Options exercised and shares vested	0.14
Weighted-Average Exercise Price, Options repurchased	0.14
Weighted-Average Exercise Price, Ending Balance	2.25		$ 0.14
Weighted-Average Exercise Price, Options vested and expected to vest as of June 30, 2015 (unaudited)	1.61
Weighted-Average Exercise Price, Options exercisable as of June 30, 2015 (unaudited)	$ 2.83
Weighted Average Remaining Contractual Life (in years)
Weighted Average Remaining Contractual Life (in years), Balance	9 years 9 months		9 years 2 months 9 days
Weighted Average Remaining Contractual Life, Options vested and expected to vest as of June 30, 2015 (unaudited)	9 years 6 months 4 days
Weighted Average Remaining Contractual Life, Options exercisable as of June 30, 2015 (unaudited)	9 years 9 months

Stock-based Awards - Schedule o

Stock-based Awards - Schedule of Fair Value of Employee Stock Options Estimated with Weighted-Average Assumptions (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Abstract]
Expected volatility	75.77%		75.77%
Risk free interest rate	1.69%		1.69%
Expected term (in years)	6 years		6 years

Stock-based Awards - Summary 39

Stock-based Awards - Summary of Stock-based Compensation Expense Net of Estimated Forfeitures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 963	$ 15	$ 989	$ 31
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	88	4	96	9
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 875	$ 11	$ 893	$ 22

Net Loss per Share - Computatio

Net Loss per Share - Computation of Basic and Diluted Net loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator:
Net loss	$ (7,376)	$ (2,763)	$ (10,817)	$ (4,357)
Denominator:
Shares used in computing net loss per share, basic and diluted	4,618,633	2,926,665	4,422,995	2,926,665
Net loss per common share, basic and diluted	$ (1.60)	$ (0.94)	$ (2.45)	$ (1.49)

Net Loss per Share -Schedule of

Net Loss per Share -Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss per Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	25,051,257	13,263,967	21,713,994	13,263,967
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	1,942,218	2,247,212	3,672,867	2,247,212

Subsequent Events - Additional

Subsequent Events - Additional Information (Details) - Subsequent Event - shares	1 Months Ended
	Aug. 31, 2015	Jul. 31, 2015
Corporate Headquarters and Research Facility
Subsequent Event [Line Items]
Term of lease for corporate headquarters	72 months
2015 Plan
Subsequent Event [Line Items]
Common stock initially reserved for issuance		4,681,544

Subsequent Events - Schedule of

Subsequent Events - Schedule of Future Aggregate Minimum Facility Lease Payments (Details) - Corporate Headquarters and Research Facility - Subsequent Event $ in Thousands	Aug. 31, 2015USD ($)
Operating Leased Assets [Line Items]
2,015	$ 190
2,016	1,010
2,017	1,602
2,018	1,650
and after	5,265
Total	$ 9,717