Ignyta 10-K 14 Mar 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Feb. 29, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	RXDX
Entity Registrant Name	IGNYTA, INC.
Entity Central Index Key	1,557,421
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		32,339,081
Entity Public Float			$ 230

Balance Sheets

Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 46,383	$ 6,346
Short-term investment securities	85,420	63,201
Prepaid expenses and other current assets	4,405	1,732
Total current assets	136,208	71,279
Long-term investment securities	40,346	7,087
Property and equipment, net	18,764	6,281
Other assets	830	659
Total assets	196,148	85,306
Current liabilities:
Accounts payable	3,828	977
Accrued expenses and other liabilities	13,860	4,930
Note payable, current portion	6,889	1,400
Lease payable, current portion	181	172
Total current liabilities	24,758	7,479
Note payable, net of current portion and discount	23,241	18,830
Lease payable, net of current portion	164	344
Other long-term liabilities	12,000	2,704
Total liabilities	$ 60,163	$ 29,357
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.0001 par; 10,000,000 shares authorized; no shares issued or outstanding
Common stock, $0.0001 par; 150,000,000 shares authorized; 32,339,081 and 19,584,769 shares issued and outstanding at December 31, 2015 and 2014, respectively	$ 3	$ 2
Additional paid-in capital	284,252	111,563
Accumulated deficit	(148,021)	(55,563)
Accumulated other comprehensive loss	(249)	(53)
Total stockholders' equity	135,985	55,949
Total liabilities and stockholders' equity	$ 196,148	$ 85,306

Balance Sheets (Parenthetical)

Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 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	$ 0.0001	$ 0.0001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	32,339,081	19,584,769
Common stock, shares outstanding	32,339,081	19,584,769

Statements of Operations and Co

Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Revenue		$ 150
Operating expenses:
Research and development	$ 73,511	30,505	$ 10,171
General and administrative	17,069	9,506	3,733
Total operating expenses	90,580	40,011	13,904
Loss from operations	(90,580)	(39,861)	(13,904)
Other income (expense):
Interest expense	(2,593)	(1,362)	(205)
Other income (expense)	715	1,233	(105)
Total other income (expense)	(1,878)	(129)	(310)
Net loss	$ (92,458)	$ (39,990)	$ (14,214)
Net loss per share:
Net loss per common share - basic and diluted	$ (3.44)	$ (2.18)	$ (3.83)
Weighted-average shares	26,854	18,328	3,712
Comprehensive loss:
Net loss	$ (92,458)	$ (39,990)	$ (14,214)
Unrealized loss on available-for-sale investment securities	(196)	(53)
Comprehensive loss	$ (92,654)	$ (40,043)	$ (14,214)

Statements of Stockholders' Equ

Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Comprehensive Income/(Loss) [Member]
Beginning balance at Dec. 31, 2012	$ 4,561		$ 5,920	$ (1,359)
Beginning balance, shares at Dec. 31, 2012		653,334
Conversion of preferred stock in reverse merger	0	$ 0	0	0	$ 0
Conversion of preferred stock in reverse merger, shares		2,675,678
Restricted shares issued in merger	6		6
Restricted shares issued in merger, shares		1,583,336
Common stock offering, net	51,014	$ 1	51,013
Common stock offering, net shares		9,010,238
Exercise of stock options	3		3
Exercise of stock options, shares		12,290
Issuance of warrants to lender	48		48
Stock-based compensation	370		370
Net loss	(14,214)			(14,214)
Ending balance at Dec. 31, 2013	41,788	$ 1	57,360	(15,573)
Ending balance, shares at Dec. 31, 2013		13,934,876
Common stock offering, net	51,582	$ 1	51,581
Common stock offering, net shares		6,031,750
Exercise of stock options	7		7
Exercise of stock options, shares		18,143
Repurchase of unvested restricted stock	(1)		(1)
Repurchase of unvested restricted stock, shares		(400,000)
Reclassification of warrant from liability	125		125
Issuance of warrants to lender	208		208
Stock-based compensation	2,283		2,283
Net loss	(39,990)			(39,990)
Unrealized loss on investment securities	(53)				(53)
Ending balance at Dec. 31, 2014	55,949	$ 2	111,563	(55,563)	(53)
Ending balance, shares at Dec. 31, 2014		19,584,769
Common stock offering, net	141,589	$ 1	141,588
Common stock offering, net shares		9,944,464
Other issuances of common stock	25,296		25,296
Other issuances of common stock, shares		2,713,000
Exercise of stock options	$ 391		391
Exercise of stock options, shares	77,477	74,529
Net exercise of warrants	$ 0	$ 0	0	0	0
Net exercise of warrants, shares		22,319
Issuance of warrants to lender	69		69
Stock-based compensation	5,345		5,345
Net loss	(92,458)			(92,458)
Unrealized loss on investment securities	(196)				(196)
Ending balance at Dec. 31, 2015	$ 135,985	$ 3	$ 284,252	$ (148,021)	$ (249)
Ending balance, shares at Dec. 31, 2015		32,339,081

Statements of Cash Flows

Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net loss	$ (92,458)	$ (39,990)	$ (14,214)
Adjustments to reconcile net loss to net cash used in operating activities:
In-process research and development charge associated with asset acquisition	11,880
Issuance of common stock for technology	13,416
Stock-basedcompensation	5,345	2,283	370
Depreciation and amortization of property and equipment	2,037	528	112
Accretion and amortization of investment securities	1,358	887
Amortization of non-cash financing costs	538	368	153
Other	2		153
Change in operating assets and liabilities:
Prepaid expenses and other assets	(2,700)	(801)	(673)
Accounts payable	2,856	164	520
Accrued expenses and other liabilities	6,926	4,073	504
Net cash used in operating activities	(50,800)	(32,488)	(13,075)
Cash flows from investing activities
Purchases of investment securities	(148,111)	(89,286)
Maturities and sales of investment securities	90,662	18,058
Purchases of property and equipment	(3,522)	(3,117)	(688)
Proceeds from sale of equipment		16	10
Net cash used in investing activities	(60,971)	(74,329)	(678)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	141,589	51,582	51,014
Proceeds from issuance of notes payable	10,000	21,000	11,000
Proceeds from exercise of stock options	391	7	3
Repayments under note and capital lease obligations	(172)	(10,023)	(1,500)
Payment of deferred financing costs		(1,050)
Other		(157)	8
Net cash provided by financing activities	151,808	61,359	60,525
Net increase (decrease) in cash and cash equivalents	40,037	(45,458)	46,772
Cash and cash equivalents at beginning of period	6,346	51,804	5,032
Cash and cash equivalents at end of period	46,383	6,346	51,804
Supplemental disclosure of cash flow information:
Cash paid for interest	2,528	1,884	51
Non-cash financing activity:
Capitalized costs associated with leased building (Note 5)	11,000
Final loan fee and warrant issuance recorded as debt discount	369	838	$ 1,078
Unrealized loss on available-for-sale investment securities	$ 196	53
Leasehold improvements paid by lessor		2,342
Assets acquired under capital leases		538
Warrant reclassified to equity due to removal of anti-dilution provision		$ 125

Organization

Organization	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	1. ORGANIZATION Organization and Nature of Operations Ignyta, Inc. (“Ignyta” or the “Company”) is incorporated in the state of Delaware and was founded in 2011 (with the name “NexDx, Inc.”). The Company changed its name to “Ignyta, Inc.” on October 8, 2012. The Company is a precision oncology biotechnology company. Its goal is not just to shrinking tumors, but to eradicate residual disease – the source of cancer relapse and recurrence – in precisely defined patient populations. The Company is pursuing an integrated therapeutic (Rx) and companion diagnostic (Dx) strategy for treating cancer patients. Its Rx efforts are focused on discovering, in-licensing or acquiring, then developing and commercializing molecularly targeted therapies that, sequentially or in combination, are foundational for eradicating residual disease. Its Dx efforts aim to pair these product candidates with biomarker-based companion diagnostics that are designed to precisely identify, at the molecular level, the patients who are most likely to benefit from the therapies it develops. On October 31, 2013, the Company merged with and into IGAS Acquisition Corp., a wholly owned subsidiary of Ignyta, Inc., a Nevada corporation previously named “Infinity Oil & Gas Company” (“Parent”), formerly a “shell company” under applicable rules of the Securities and Exchange Commission (the “SEC”). The Company changed its name to Ignyta Operating, Inc. in connection with this merger, and it survived the merger as a wholly owned subsidiary of Parent. In the merger, Parent acquired the business of the Company and continued the business operations of the Company. The merger was accounted for as a reverse merger and recapitalization, with the Company as the acquirer and Parent as the acquired company for financial reporting purposes. As a result, the assets and liabilities and the operations that are reflected in the historical financial statements prior to the merger are those of the Company and are recorded at the historical cost basis of the Company, and the financial statements after completion of the merger will include the assets and liabilities of Parent and the Company, the historical operations of the Company and the operations of the combined enterprise of Parent and the Company from and after the closing date of the merger. On June 12, 2014, Parent merged with and into the Company, with the Company surviving the merger and changing its name to “Ignyta, Inc.” (the “Reincorporation Merger”). This Reincorporation Merger had no material impact on the accounting of the Company. Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business as one operating segment. Liquidity The Company had negative cash flow from operations of approximately $50.8 million during 2015 and, as of December 31, 2015, had an accumulated deficit of approximately $148.0 million. The Company is focused primarily on its development programs, and management believes such activities will result in the continued incurrence of significant research and development and other expenses related to those programs. The Company expects that it will need additional capital to further fund development of, and seek regulatory approvals for, its product candidates, and begin to commercialize any approved products. If the clinical trials for any of the Company’s products fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of its product candidates, if approved, fails to achieve market acceptance, the Company may never become profitable. Even if the Company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. The Company intends to cover its future operating expenses through cash on hand and through additional financing from existing and prospective investors. The Company cannot be sure that additional financing will be available when needed or that, if available, financing will be obtained on terms favorable to the Company or to its stockholders. As of December 31, 2015, the Company had cash, cash equivalents and available-for-sale securities totaling $172.1 million. While the Company expects that its existing cash, cash equivalents and available-for-sale securities will enable it to fund its operations and capital expenditure requirements for at least the next twelve months, having insufficient funds may require the Company to delay, reduce, limit or terminate some or all of its development programs or future commercialization efforts or grant rights to develop and market product candidates that it would otherwise prefer to develop and market on its own. Failure to obtain adequate financing could eventually adversely affect the Company’s ability to operate as a going concern. If the Company raises additional funds from the issuance of equity securities, substantial dilution to its existing stockholders would likely result. If the Company raises additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict its ability to operate its business.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles, or GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities. Significant estimates used in preparing the financial statements include those assumed in estimating expenses for the Company’s pre-clinical studies and clinical trials, computing the valuation allowance on deferred tax assets, calculating stock-based compensation expense and for determining the value of leased property during the construction period for which the Company has been deemed the accounting owner. Actual results could differ from those estimates. Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of 90 days or less when purchased to be cash equivalents. Cash equivalents primarily represent amounts invested in money market funds whose cost equals market value. Investment Securities Investment securities consist of government and government agency obligations, corporate notes and bonds and commercial paper. The Company classifies its investment securities as available-for-sale at the time of purchase. All investment securities are recorded at estimated fair value. Unrealized gains and losses for available-for-sale investment securities are included in accumulated other comprehensive income or loss, a component of stockholders’ equity. The Company evaluates its investment securities as of each balance sheet date to assess whether those with unrealized loss positions are other-than-temporarily impaired. Impairments are considered to be other-than-temporary if they are related to deterioration in credit risk or if it is likely that the Company will sell the securities before the recovery of its cost basis. Realized gains and losses and declines in value judged to be other-than-temporary are determined based on the specific identification method. No other-than-temporary impairment charges have been recognized since inception. Fair Value of Financial Instruments Financial assets and liabilities are measured at fair value, which is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The Company’s financial instruments consist of cash and cash equivalents, investment securities, prepaid expenses and other assets, accounts payable, accrued expenses, and notes payable. The valuation of assets and liabilities is subject to fair value measurements using a three tiered approach, and fair value measurement is classified and disclosed in one of the following categories: Level 1: Quoted prices in active markets for identical assets or liabilities; Level 2: Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; or Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Fair value estimates of these instruments at a specific point in time are made based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of judgment and therefore cannot be determined with precision. The Company reports its available-for-sale securities at their estimated fair values based on quoted market prices for identical or similar instruments. The book values of cash and cash equivalents, prepaid expenses and other assets, accounts payable, accrued expenses, notes payable and other liabilities are reasonable estimates of fair value because of the short-term nature of these items. Credit Risk Cash is invested in accordance with a policy approved by the Company’s board of directors which specifies the categories, allocations, and ratings of securities that the Company may consider for investment. Management does not believe that the Company’s cash, cash equivalents and available-for-sale investment securities have significant risk of default or illiquidity. This determination is based on discussions with the Company’s treasury managers and a review of the Company’s holdings. While the Company believes that its cash, cash equivalents and available-for-sale investment securities are well diversified and do not contain excessive risk, the Company cannot provide absolute assurance that its investments will not be subject to future adverse changes in market value. The Company maintains cash balances at various financial institutions. Accounts at these institutions are secured by the Federal Deposit Insurance Corporation. At times these balances exceed federally insured limits. The Company has not experienced any losses in such accounts. With respect to the Company’s cash equivalents and available-for-sale investment securities, the primary exposure to market risk is interest rate sensitivity. This means that a change in prevailing interest rates may cause the value of the investment to fluctuate. For example, if the Company purchases a security that was issued with a fixed interest rate and the prevailing interest rate later rises, the value of this investment will probably decline. Currently, the Company’s holdings are in money market funds and available-for-sale investment securities, and therefore this interest rate risk is minimal. To minimize interest rate risk going forward, the Company intends to continue to maintain its portfolio of cash, cash equivalents and available-for-sale investment securities in a variety of securities consisting of money market funds and debt securities, all with various maturities. In general, money market funds are not subject to market risk because the interest paid on such funds fluctuates with the prevailing interest rate. The Company also attempts to time the maturities of its investments to correspond with expected cash needs, allowing it to avoid realizing any potential losses from having to sell securities prior to their maturities. Property and Equipment Property and equipment are recorded at cost. Depreciation is computed using the straight-line method over the estimated useful lives of the related assets, which generally range from three to seven years, or, in the case of leasehold improvements, over the lesser of the useful life of the related asset or the lease term. The Company reviews property and equipment for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. An impairment loss would be recognized when estimated future undiscounted cash flows relating to the asset are less than its carrying amount. An impairment loss is measured as the amount by which the carrying amount of an asset exceeds its fair value. To date, the Company has not experienced any impairment losses on its property and equipment. The Company establishes assets and corresponding financing liabilities for the construction costs incurred under build-to-suit lease arrangements when it is determined that the Company takes construction risks during the construction period and is deemed the accounting owner of the property during construction. At the end of the construction period, the Company assesses whether the arrangement qualifies for sales recognition under the sale-leaseback accounting guidance in ASC 840. Clinical Trial and Pre-Clinical Study Accruals The Company makes estimates of accrued expenses as of each balance sheet date in its financial statements based on the facts and circumstances known to it at that time. Accrued expenses for pre-clinical studies and clinical trials are based on estimates of costs incurred and fees that may be associated with services provided by contract research organizations, clinical trial investigational sites, and other related vendors. Payments under certain contracts with such parties depend on factors such as successful enrollment of patients, site initiation and the completion of milestones. In accruing service fees, management estimates the time period over which services will be performed and the level of effort to be expended in each period. If possible, the Company obtains information regarding unbilled services directly from these service providers. However, the Company may be required to estimate these services based on other information available to it. If the Company underestimates or overestimates the activity or fees associated with a study or service at a given point in time, adjustments to research and development expenses may be necessary in future periods. Historically, estimated accrued liabilities have approximated actual expense incurred. Subsequent changes in estimates may result in a material change in the Company’s accruals. Income Taxes Deferred income taxes are recognized for the tax consequences in future years of differences between the tax basis of assets and liabilities and their financial reporting amounts at each year end based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. Income tax expense is the combination of the tax payable for the year and the change during the year in deferred tax assets and liabilities. The Company follows the accounting guidance on accounting for uncertainty in income taxes. The guidance prescribes a recognition threshold and measurement attribute criteria for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities based on the technical merits of the position. Research and Development Costs incurred in connection with research and development activities are expensed as incurred. Research and development expenses consist of (i) external research and development expenses incurred under arrangements with third parties, such as contract research organizations, investigational sites and consultants; (ii) employee-related expenses, including salaries, benefits, travel and stock compensation expense; (iii) the cost of acquiring, developing and manufacturing clinical study materials; (iv) facilities and other expenses, which include direct and allocated expenses for rent and maintenance of facilities and laboratory and other supplies, and (v) license fees and other expenses relating to the acquisition of rights to our development programs. The Company enters into consulting, research and other agreements with commercial firms, researchers, universities and others for the provision of goods and services. Under such agreements, the Company may pay for services on a monthly, quarterly, project or other basis. Such arrangements are generally cancellable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided to the Company by its clinical sites and vendors and other information. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. In certain circumstances, the Company is required to make advance payments to vendors for goods or services that will be received in the future for use in research and development activities. In such circumstances, the advance payments are deferred and are expensed when the activity has been performed or when the goods have been received. Stock-Based Compensation Stock-based compensation cost for equity awards to employees and members of the Company’s board of directors is measured at the grant date, based on the calculated fair value of the award using the Black-Scholes option-pricing model, and is recognized as an expense, under the straight-line method, over the requisite service period (generally the vesting period of the equity grant). Stock options issued to non-employees are accounted for at their estimated fair values determined using the Black-Scholes option-pricing model. The fair value of options granted to non-employees is re-measured as they vest, and the resulting increase in value, if any, is recognized as an expense during the period the related services are rendered. Restricted stock issued to non-employees is accounted for at its estimated fair value as it vests. Comprehensive Income Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company is required to record all components of comprehensive income (loss) in the financial statements in the period in which they are recognized. Net income (loss) and other comprehensive income (loss), including unrealized gains and losses on available-for-sale investments, are reported net of their related tax effect, to arrive at comprehensive income (loss). Net Loss per Share Basic and diluted loss per common share have been computed by dividing the losses applicable to common stock by the weighted average number of common shares outstanding. The Company’s basic and fully diluted loss per common share calculations are the same since the increased number of shares that would be included in the diluted calculation from the assumed exercise of stock equivalents would be anti-dilutive to the net loss in each of the years shown in the financial statements. The calculations of net loss per share excluded potentially dilutive securities (consisting of outstanding options, warrants, restricted stock and restricted stock units) of approximately 5.4 million and 3.1 million shares as of December 31, 2015 and 2014, respectively. Recent Accounting Pronouncements In January 2016, the FASB issued an accounting standard update, or ASU, which addresses certain aspects of recognition, measurement, presentation and disclosure of certain assets and liabilities in financial statements. This guidance will be effective in the first quarter of fiscal year 2018 and early adoption is not permitted. The Company is currently evaluating the impact that this guidance will have on its financial statements. In November 2015, the FASB issued an ASU which requires that deferred tax assets and liabilities be classified as noncurrent rather than being separated into current and noncurrent components. This new guidance will be effective in the first quarter of fiscal 2017. This guidance is not expected to have a material impact on our financial statements. In April 2015, the FASB issued an accounting standard update which requires presentation of debt issuance costs as a direct deduction from the carrying amount of a recognized debt liability on the balance sheet, consistent with the treatment of debt discounts. The update does not change the guidance on the recognition and measurement of debt issuance costs. The Company intends to adopt this guidance at the beginning of its first quarter of fiscal year 2016. At the time of adoption, the Company will reclassify debt issuance costs to a liability as a direct deduction from the carrying value of the debt, consistent with the presentation of a debt discount. The adoption of this update is not expected to have a material impact on the Company’s financial statements. In August 2014, the FASB issued an ASU that requires management to evaluate whether there are conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern, and to provide certain disclosures when it is probable that the entity will be unable to meet its obligations as they become due within one year after the date that the financial statements are issued. The Company intends to adopt this guidance at the beginning of its first quarter of fiscal year 2016. Since this guidance is primarily around certain disclosures in the financial statements, the Company anticipates no impact on its financial position or results of operations. In May 2014, the FASB issued an ASU that supersedes or replaces nearly all revenue recognition guidance. The new guidance establishes a new control-based revenue recognition model, changes the basis for deciding when revenue is recognized over time or at a point in time and will expand disclosures about revenue. Companies may use either a full retrospective or a modified retrospective approach to adopt this guidance. The Company is evaluating which transition approach to use and its impact, if any, on its financial statements. This ASU is effective for the fiscal year beginning January 1, 2019, and early adoption is not permitted. Reclassifications Certain reclassifications have been made to prior year amounts to conform to the current year presentation. These changes had no impact on the Company’s total assets or reported net loss.

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2015
Investments Schedule [Abstract]
Investment Securities	3. INVESTMENT SECURITIES The following tables summarize the available-for-sale investments held by the Company as of the dates below ( in thousands As of December 31, 2015 Amortized Cost Gross Gross Fair Available-for-sale investment securities: Commercial paper, short-term $ 7,992 $ — $ — $ 7,992 Corporate debt securities, short-term 70,505 1 (80 ) 70,426 Corporate debt securities, long-term 24,454 2 (100 ) 24,356 U.S. government and agency obligations, short-term 7,009 — (7 ) 7,002 U.S. government and agency obligations, long-term 16,055 — (65 ) 15,990 Total $ 126,015 $ 3 $ (252 ) $ 125,766 As of December 31, 2014 Amortized Cost Gross Gross Fair Available-for-sale investment securities: Commercial paper, short-term $ 3,896 $ — $ — $ 3,896 Corporate debt securities, short-term 59,343 — (38 ) 59,305 Corporate debt securities, long-term 7,102 — (15 ) 7,087 Total $ 70,341 $ — $ (53 ) $ 70,288 None of the Company’s available-for-sale investment securities held at December 31, 2015 had maturity dates of more than 24 months. The Company determines the appropriate designation of investments at the time of purchase and reevaluates such designation as of each balance sheet date. Investment securities classified as short-term investments have maturity dates of less than one year from the balance sheet date, while securities classified as long-term investments have maturity dates of greater than one year from the balance sheet date. The cost of securities sold is based on the specific identification method. Amortization of premiums, accretion of discounts, interest, dividend income, and realized gains and losses are included in investment income. None of the Company’s available-for-sale investment securities were in a material unrealized loss position at December 31, 2015. The Company reviewed its investment holdings as of December 31, 2015 and determined that its unrealized losses were not considered to be other-than-temporary based upon (i) the financial strength of the issuing institution and (ii) the fact that no securities have been in an unrealized loss position for twelve months or more. As such, the Company has not recognized any impairment in its financial statements related to its available-for-sale securities. The Company has not realized any significant gains or losses on sales of available-for-sale investment securities during any of the periods presented.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. FAIR VALUE MEASUREMENTS The Company holds available-for-sale securities that consist of highly liquid, investment grade debt securities. The Company determines the fair value of its available-for-sale securities based upon one or more valuations reported by its investment accounting and reporting service provider. The investment service provider values the securities using a hierarchical security pricing model that relies primarily on valuations provided by an industry-recognized valuation service. Such valuations may be based on trade prices in active markets for identical assets or liabilities (Level 1 inputs) or valuation models using inputs that are observable either directly or indirectly (Level 2 inputs), such as quoted prices for similar assets or liabilities, yield curves, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments or debt, and broker and dealer quotes, as well as other relevant economic measures. The fair value of cash, cash equivalents and available-for-sale investment securities were as follows ( in thousands As of December 31, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 46,383 $ — $ — $ 46,383 $ 6,346 $ — $ — $ 6,346 Short-term investments: Commercial paper — 7,992 — 7,992 — 3,896 — 3,896 Corporate debt securities — 70,426 — 70,426 — 59,305 — 59,305 U.S. government and U.S. government agency obligations 7,002 — — 7,002 — — — — Total short-term investments 7,002 78,418 — 85,420 — 63,201 — 63,201 Long-term investments: Corporate debt securities — 24,356 — 24,356 — 7,087 — 7,087 U.S. government and U.S. government agency obligations 15,990 — — 15,990 — — — — Total long-term investments 15,990 24,356 — 40,346 — 7,087 — 7,087 Total assets measured at fair value $ 69,375 $ 102,774 $ — $ 172,149 $ 6,346 $ 70,288 $ — $ 76,634

Balance Sheet Details

Balance Sheet Details	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance Sheet Details	5. BALANCE SHEET DETAILS Property and Equipment Property and equipment consisted of the following ( in thousands As of December 31, 2015 As of December 31, 2014 Manufacturing and lab equipment $ 6,941 $ 3,838 Leasehold improvements 2,349 2,327 Computer and office equipment 1,145 750 Construction in process (see below) 11,000 — Property and equipment at cost 21,435 6,915 Less accumulated depreciation and amortization (2,671 ) (634 ) Property and equipment, net $ 18,764 $ 6,281 Lab equipment includes assets with an acquisition value of $636,000 (net of accumulated depreciation of $144,000 and $17,000 in 2015 and 2014, respectively) which were acquired under leases accounted for as capital leases. Depreciation expense for this equipment totaled approximately $127,000 and $17,000 for 2015 and 2014, respectively. Accrued Expenses and Other Current Liabilities The following table summarizes major classes of accrued expenses and other current liabilities ( in thousands As of December 31, 2015 As of December 31, 2014 Contracted clinical trial services fees and related costs $ 5,766 $ 1,971 Research and development services 1,763 355 Personnel and related costs 3,844 1,828 Other liabilities 2,487 776 Total $ 13,860 $ 4,930 Other Long-Term Liabilities Other long-term liabilities consisted of the following ( in thousands As of December 31, 2015 As of December 31, 2014 Deferred rent, net of current portion $ 70 $ 2,074 Final loan fee obligation to lender (see note 6) 930 630 Leased facility financing obligation (see below) 11,000 — Total $ 12,000 $ 2,704 Construction in Process and Leased Facility Financing Obligation In October 2015, the Company entered into an agreement for the lease of 95,146 square feet of laboratory and office space on a build-to-suit Based on the terms of the lease agreement and applicable accounting rules, the Company was determined to bear substantially all of the construction-related risks during the construction period and was deemed the owner of the building for accounting purposes during the construction period. As a result, the Company’s balance sheet at December 31, 2015 includes a fixed asset (construction in process) and a corresponding leased facility financing obligation reflecting the estimated fair value of this facility at lease inception (of $10.9 million) and the accumulated build out costs incurred subsequent to the inception of the lease. The fair value measurement of the building is categorized within Level 3 of the fair value hierarchy. Upon completion of construction, the Company will occupy the buildings and finalize an assessment of the sale-leaseback criteria to determine whether it will de-recognize both the building assets and the corresponding liability.

Notes Payable

Notes Payable	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Notes Payable	6. NOTE PAYABLE The Company has incurred $31.0 million of indebtedness under its amended and restated loan and security agreement with Silicon Valley Bank (“SVB”). The Company is required to pay interest on the borrowings under this agreement at a fixed, per-annum rate of interest of 8.6% on a monthly basis through April 30, 2016. The loan principal will be repaid in 36 equal monthly payments commencing in May 2016, such that the loan will be fully paid by April 2019. The Company will also owe the lender a final payment of $930,000 at loan maturity. This final payment is presented as a debt discount which is being amortized to interest expense over the term of the loan. The Company may elect to prepay all amounts owed prior to the maturity date, provided that a prepayment fee equal to 1.0% of the amount prepaid is also paid. Future minimum principal payments under the Company’s note payable are as follows ( in thousands Year ending December 31, Minimum Payments 2016 $ 6,889 2017 10,333 2018 10,333 2019 3,445 Total $ 31,000 In connection with this agreement, the Company issued to SVB and its affiliate warrants to purchase an aggregate of 53,281 shares of its common stock. The fair value of these warrants has been recorded as a debt discount and is being amortized to interest expense over the term of the loan agreement. Under the terms of its loan agreement with SVB, the Company is bound by certain affirmative and negative covenants setting forth actions that it must and must not take during the term thereof. Upon the occurrence of an event of default, subject to cure periods for certain events of default, all amounts owed by the Company thereunder shall begin to bear interest at a rate of 11.6% and may be declared immediately due and payable by SVB. The Company has granted SVB a security interest in substantially all of its personal property, rights and assets, other than intellectual property, to secure the payment of all amounts owed to SVB under this agreement. The Company has also agreed not to encumber any of its intellectual property without SVB’s written consent.

Asset Acquisition

Asset Acquisition	12 Months Ended
	Dec. 31, 2015
Text Block [Abstract]
Asset Acquisition	7. ASSET ACQUISITION On March 17, 2015, under the terms of an asset purchase agreement with Cephalon, Inc. (“Cephalon”), an indirect wholly owned subsidiary of Teva Pharmaceutical Industries Ltd. (“Teva”), the Company acquired certain assets relating to four oncology development programs. The development programs that were purchased from Teva include: • RXDX-105, an orally available, small molecule multikinase inhibitor with potent activity against such targets as RET and BRAF that is currently in a Phase 1/1b dose escalation clinical trial; • RXDX-107, a new chemical entity comprising an alkyl ester of bendamustine encapsulated in human serum albumin (HSA) to form nanoparticles that is in a Phase 1/1b dose escalation clinical trial; • RXDX-106, a small molecule, pseudo-irreversible inhibitor of Tyro-3, Axl, Mer (TAM) and cMET that is in late preclinical development; and • RXDX-108, a small molecule inhibitor of the atypical kinase PKCiota that is in preclinical studies. The Company also acquired rights to certain next generation PKCiota inhibitors in addition to the lead compound. Under the asset purchase agreement, the Company acquired Cephalon’s right, title and interest in and to certain intellectual property, compounds, products, contracts, records, data and development supplies related to these programs (the “Purchased Assets”), and assumed certain related commitments. The Company did not acquire any marketable products, established customer or employee bases, or any established business, management, operational or resource management processes. Accordingly, the Company recorded this transaction as an asset purchase as opposed to a business combination. As consideration for the Purchased Assets, the Company issued to Cephalon 1,500,000 unregistered shares of the Company’s common stock and assumed certain other third-party royalty obligations (see Note 8). The acquired assets are in various stages of drug development, ranging from preclinical stage to Phase 1 clinical trials. As such, the development plans are still being formulated and are as yet incomplete. Effective February 2016, the Company ceased all development activities relating to its RXDX-107 and RXDX-108 programs. The Company will be conducting further preclinical studies and making continued assessments of potential and actual clinical development plans related to the RXDX-105 and RXDX-106 compounds. As the success of the Company’s commercialization of these acquired compounds remains uncertain and the assets in question have no alternative future uses, the Company recorded an in-process research and development charge of approximately $11.9 million during the first quarter of 2015 based on the value of the net assets exchanged for the Purchased Assets. Under the provisions of the asset purchase agreement, the Company paid approximately $0.9 million to Cephalon for drug development supplies, which was included in research and development expenses for the first quarter of 2015. Concurrent with the above transaction, Cephalon also entered into a subscription agreement with the Company whereby Cephalon agreed to purchase an additional 1,500,000 shares of the Company’s common stock at a price of $10.00 per share (see Note 10). In connection with the asset purchase agreement, the Company entered into a registration rights agreement with Cephalon pursuant to which the Company has agreed to register the shares of the Company’s common stock held by Cephalon. The Company has filed a registration statement with the SEC relating to such shares, and the SEC has declared the registration statement effective. The Company may be liable for liquidated damages if it fails to maintain the effectiveness of the registration statement, subject to certain exceptions. The amount of the liquidated damages per applicable thirty-day period is one percent of the aggregate purchase price of the registrable securities then held by each holder, subject to an aggregate cap of ten percent. The Company also agreed to other customary obligations regarding registration, including matters relating to indemnification, maintenance of the registration statement and payment of certain expenses.

License Agreements

License Agreements	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
License Agreements	8. LICENSE AGREEMENTS Entrectinib The Company entered into a license agreement with Nerviano Medical Sciences S.r.l. (“NMS”) on October 10, 2013, which was amended on October 25, 2013, became effective on November 6, 2013, and was amended December 12, 2014. The agreement grants the Company exclusive global rights to develop and commercialize entrectinib, as well as a second product candidate, RXDX-102. Based on clinical trial results relating to entrectinib that have been seen to date, the Company designated RXDX-102 as a back-up compound to entrectinib. Accordingly, the Company will not devote further development resources to RXDX-102. The Company’s development rights under the license agreement are exclusive for the term of the agreement with respect to entrectinib and RXDX-102 and also, as to NMS, are exclusive for a five-year period with respect to any product candidate with activity against the target proteins of entrectinib and RXDX-102, and include the right to grant sublicenses. The Company is obligated under the license agreement to use commercially reasonable efforts to develop and commercialize a product based on either or both of entrectinib and RXDX-102, at its expense. The terms of the license agreement provided for an up-front payment to NMS of $7.0 million, which was paid in November 2013 and expensed as research and development (as no future benefit was determined to exist at that time). When and if commercial sales of a product based on either or both of entrectinib or RXDX-102 begin, the Company will be obligated to pay NMS tiered royalties ranging from a mid-single digit percentage to a low double digit percentage (between 10% and 15%) of net sales, depending on the amount of net sales, with standard provisions for royalty offsets to the extent it obtains any rights from third parties to commercialize the product. The Company was also obligated under the terms of the license agreement to engage NMS to perform services valued at $1.0 million prior to December 31, 2014, which obligation had been met prior to that time. The license agreement also requires that the Company makes development and regulatory milestone payments to NMS of up to $105.0 million in the aggregate if specified clinical study initiations and regulatory approvals are achieved across multiple products or indications. Pursuant to the December 2014 amendment to the agreement, the Company paid the initial milestone payment of $10.0 million to NMS in December 2014, which was expensed as research and development (as no future benefit was determined to exist at that time). Taladegib On November 6, 2015, the Company entered into a license, development and commercialization agreement with Eli Lilly and Company (“Lilly”) under which the Company received exclusive, global rights to develop and commercialize pharmaceutical products under the licensed technology (“Licensed Products”), including Lilly’s product candidate taladegib. Taladegib is an orally bioavailable, small molecule hedgehog/smoothened antagonist that has achieved clinical proof of concept and a recommended Phase 2 dose in a Phase 1 dose escalation trial. The Company granted back to Lilly an exclusive license to develop and commercialize pharmaceutical products comprising taladegib in combination with certain other molecules (“Combination Products”). The Company also licensed the exclusive worldwide rights to the topical formulation of taladegib, which is a late preclinical development program for the potential treatment of patients with superficial and nodular basal cell carcinoma. In February 2016, the Company ceased all development activities relating to the topical taladegib program. The Company’s rights under the agreement are exclusive for the term of the agreement. Both parties’ rights under the agreement include the right to grant sublicenses. The Company is obligated under the agreement to use commercially reasonable efforts to develop and commercialize Licensed Products, at its expense. Both parties have a right to terminate the agreement if the other party enters bankruptcy, upon an uncured breach by the other party or if the other party challenges its patents relating to the licensed technology. The terms of the license agreement provided for an up-front payment to Lilly of $2.0 million, plus the issuance to Lilly in a private placement of 1,213,000 shares of the Company’s common stock. The Company recorded a charge of approximately $13.4 million during the fourth quarter of 2015 based on the value of the shares issued for the license from Lilly. The license agreement also requires that the Company makes development and sales milestone payments to Lilly of up to $38.0 million. The Company may elect to pay a portion of such amounts by issuing to Lilly shares of its common stock in a private placement, subject to certain conditions. In addition, a portion of the $30 million in gross proceeds provided to the Company by Lilly in a concurrent private placement of the Company’s common stock to Lilly (see Note 10) has been earmarked for payment of milestone obligations under the license agreement. When and if commercial sales of Licensed Products begin, the Company will be obligated to pay Lilly a mid-single digit royalty of net sales of Licensed Products. When and if commercial sales of Combination Products begin, Lilly will be obligated to pay the Company a mid-single digit royalty of net sales of Combination Products. Both parties’ royalty obligations are subject to standard provisions for royalty offsets to the extent a party is required to obtain any rights from third parties to commercialize the applicable products, or in the event of loss of exclusivity or generic competition. RXDX-103 and RXDX-104 On August 4, 2014, the Company entered into a second license agreement with NMS, which agreement was amended on August 31, 2015. The agreement grants the Company exclusive global rights to develop and commercialize RXDX-103, as well as a second development program, RXDX-104. Based on preclinical activities relating to RXDX-104, in December 2014, the Company decided to discontinue development of RXDX-104, and the Company will not devote further development resources to this program. Pursuant to the August 2015 amendment, the Company returned all rights to RXDX-104 to NMS in exchange for a right of first refusal to license rights to any RET inhibitor that NMS contemplates licensing to any third party prior to August 31, 2016. In February 2016, the Company ceased all development activities relating to the RXDX-103 program. Under the license agreement, the Company made an up-front payment to NMS of $3.5 million in August 2014, which was expensed to research and development (as no future benefit was determined to exist at that time). RXDX-105 and RXDX-106 In connection with the March 2015 asset acquisition from Cephalon, the Company assumed all rights and obligations under the collaboration agreement dated November 3, 2006, as amended April 17, 2009, between Cephalon, Inc. and Daiichi Sankyo Company, Limited (“Daiichi Sankyo”), as successor-in-interest to Ambit Biosciences Corporation. The collaboration was for the purpose of identifying and developing clinical candidates that demonstrate activity towards the two designated target kinases of the collaboration: the BRAF kinase and the Axl kinase. Under the agreement, both parties contributed certain intellectual property to the collaboration and agreed to a period of exclusivity during which neither party would engage in any research related to a collaboration target compound with any third-party. The collaboration portion of the agreement ended in November 2009, but the agreement remains in effect on a product-by-product, country-by-country basis until all royalty obligations expire. Both parties have a right to terminate the agreement if the other party enters bankruptcy or upon an uncured breach by the other party. The Company may also terminate the agreement in its discretion upon 90 days’ written notice to Daiichi Sankyo. The Company is solely responsible for worldwide clinical development and commercialization of collaboration compounds, subject to the option of Daiichi Sankyo, exercisable during certain periods following completion of the first proof-of-concept study in humans and only with the consent of the Company, to co-develop and co-promote RXDX-105. If the Company decides to discontinue development of the RXDX-105 program, it must give written notice to Daiichi Sankyo, which will have the right to assume control of that program, subject to diligence obligations and payment of the milestones and royalties to the Company that would otherwise have been paid to Daiichi Sankyo had the Company maintained responsibility for the program. The agreement requires the Company to make development, regulatory and sales milestone payments to Daiichi Sankyo of up to $44.5 million in the aggregate for RXDX-105, and up to $47.5 million in payments upon the achievement of development, regulatory and sales milestones for RXDX-106. When and if commercial sales of a product based on either of RXDX-105 or RXDX-106 begin, the Company will be obligated to pay Daiichi Sankyo tiered royalties ranging from a mid-single digit percentage to a low double digit percentage of net sales, depending on annual amounts of net sales, with standard provisions for royalty offsets to the extent it is required to obtain any rights from third parties to commercialize either RXDX-105 or RXDX-106. Royalties are payable to Daiichi Sankyo on a product-by-product, country-by-country basis beginning on the date of the first commercial sale in a country and ending on the later of 10 years after the date of such sale in that country or the expiration date of the last to expire licensed patent covering the product in that country. RXDX-108 In connection with the March 2015 asset acquisition from Cephalon, the Company assumed all rights and obligations under the license agreement dated January 20, 2014, between Teva Branded Pharmaceutical Products R&D, Inc. and Cancer Research Technology Limited (“CRT”). The agreement grants the Company exclusive global rights to develop and commercialize RXDX-108. The Company also received rights to certain other next generation PKCiota inhibitors. In February 2016, the Company notified CRT that it intended to terminate the RXDX-108 drug development program, effective immediately. The Company does not have a unilateral right to terminate the license agreement, but it has engaged CRT in discussions regarding the mutual termination of the license agreement.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. COMMITMENTS AND CONTINGENCIES Leases The Company leases office and laboratory space and certain lab equipment under operating leases that expire through 2026. Certain of the facility leases contain periodic rent increases that result in the Company recording deferred rent over the term of these leases. Rental expense under leases was $636,000, $495,000 and $208,000 for the years ended December 31, 2015, 2014 and 2013, respectively. The Company has also entered into capital lease arrangements for the purchase of certain lab equipment. The Company’s non-cancellable future minimum annual lease payments under its capital and operating leases for the years ending after December 31, 2015 are as follows (in thousands): Capital Operating Leases Leases 2016 $ 194 $ 1,541 2017 167 2,852 2018 — 4,482 2019 — 4,500 2020 — 4,635 Thereafter — 8,435 Total minimum lease payments 361 $ 26,445 Less amount representing interest (16 ) Present value of obligations under capital leases 345 Less current portion (181 ) Long-term capital lease obligations $ 164 In October 2015, the Company entered into a commercial lease agreement that provides for the Company to lease office and laboratory space in two separate buildings in San Diego, California (Note 5). The lease on this new facility has a ten-year term, which is expected to commence in the fourth quarter of 2016. The lease contains a one-time provision to terminate the lease for all or a portion of the facilities, effective as of the end of the 72 nd Clinical Trial Study Agreement Commitments The Company has entered into agreements with several contract research organizations for clinical studies to be conducted both within and outside the U.S. for its product candidates. The total contracted cost under these arrangements totaled approximately $68.9 million as of December 31, 2015, of which approximately $15.0 million has been incurred to date. These agreements run through various dates, with the longest term expected to run through 2020. These contracts can be terminated at any time with no more than 60 days’ notice, at which point the Company would be obligated to pay for costs incurred though the termination date.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	10. STOCKHOLDERS’ EQUITY Authorized Shares The Company is authorized to issue 150,000,000 shares of common stock and 10,000,000 shares of preferred stock, with the preferred stock having the rights, preferences and privileges that the Company’s board of directors may determine from time to time. Each share of the Company’s common stock is entitled to one vote, and all shares rank equally as to voting and other matters. Stock Offerings In November 2015, concurrent with its license agreement with Lilly (see Note 8), the Company issued and sold 1,500,000 shares of its common stock to Lilly for net proceeds of approximately $30.0 million (the transaction costs were negligible). The Company also entered into a registration rights agreement with Lilly pursuant to which the Company agreed to register the resale of the shares of the Company’s common stock held by Lilly. The Company may be liable for liquidated damages if it fails to timely file, obtain effectiveness or maintain the effectiveness of the registration statement. In June 2015, the Company completed a public stock offering providing for the issuance and sale to investors of an aggregate of 4,285,714 shares of its common stock for net proceeds of approximately $70.1 million (net of transaction costs of $4.9 million). In March 2015, concurrent with its asset purchase agreement with Cephalon (see Note 7), the Company issued and sold 4,158,750 shares of common stock to Cephalon and several additional investors in a registered direct offering. The net proceeds from this offering totaled approximately $41.4 million (net of transaction costs of $149,000). In March 2014, the Company completed a public stock offering providing for the issuance and sale to investors of an aggregate of 6,031,750 shares of its common stock for net proceeds of approximately $51.6 million (net of transaction costs of $3.6 million). In November 2013, the Company issued an aggregate of 9,010,238 shares of common stock to a group of accredited investors in private placements. The shares were sold for net proceeds of $51.0 million (net of transaction costs of $3.0 million). At-The-Market Issuance Sales Agreement In December 2015, the Company entered into an “at-the-market” issuance sales agreement (the “Sales Agreement”) with Cantor Fitzgerald& Co. (“Cantor”), pursuant to which the Company may issue and sell shares of its common stock from time to time, at the Company’s option, through Cantor as its sales agent. The Company is not obligated to make any sales of its common stock under the Sales Agreement, and it may terminate its agreement with Cantor at any time. Any shares sold will be sold pursuant to an effective shelf registration statement on Form S-3. Restricted Stock The Company issued restricted shares in 2013 and 2011. An aggregate of 10,628 shares associated with restricted stock arrangements were subject to future vesting as of December 31, 2015. The Company’s restricted stock arrangements allow it to repurchase any unvested shares of stock in the event the holder ceases providing services to the Company. No restricted shares were repurchased during fiscal 2015 or 2013. During 2014, the Company repurchased 400,000 restricted shares for $1,440. Common Stock Warrants Warrants to purchase an aggregate of 59,356 shares of the Company’s common stock were outstanding at December 31, 2015. These warrants have exercise prices ranging from $3.00 to $8.78 per share, and expire at various dates through September 2022. Conversion of Preferred Stock During fiscal 2013, the Company converted all of its then outstanding preferred shares into 2,675,678 shares of common stock.

Equity Awards

Equity Awards	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Awards	11. EQUITY AWARDS Equity Incentive Plans The Company issues equity awards under its 2015 Employment Inducement Incentive Award Plan (the “2015 Inducement Plan”) and its 2014 Incentive Award Plan (the “2014 Plan”). The 2015 Inducement Plan provides for the issuance of up to 2,000,000 shares, while the 2014 Plan provides for the issuance of up to 3,000,000 shares, plus one additional share for each option share granted under the Company’s 2011 Incentive Award Plan (the “2011 Plan”) that expires, is forfeited or is settled in cash subsequent to June 11, 2014. Both award plans allow for the issuance of equity awards to either employees or non-employees, however awards under the 2015 Inducement Plan may only be made to an employee who meets certain criteria (the award must be made in connection with commencement of employment and such award must be a material inducement to entering into employment). Prior to the adoption of the 2015 Inducement Plan and the 2014 Plan, the Company granted equity awards under the 2014 Employment Inducement Incentive Award Plan and the 2011 Plan. No additional equity grants may be made by the Company under either of these predecessor plans. A summary of the Company’s equity incentive plan activity and other related information is as follows: Options Weighted- Weighted- Aggregate Balance at December 31, 2014 2,991,655 $ 6.67 9.21 $ 2,482,181 Granted 2,695,991 11.63 Exercised (77,477 ) 5.66 Forfeited (359,229 ) 7.74 Balance at December 31, 2015 5,250,940 $ 9.16 8.83 $ 24,565,711 Exercisable at December 31, 2015 1,206,105 $ 6.07 8.05 $ 8,837,446 As of December 31, 2015, an aggregate of 1,674,558 shares remain available for grant under the Company’s equity incentive plans. Options granted under the Company’s equity incentive plans are exercisable at various dates and will expire no more than ten years from their date of grant. The exercise price of each option to be granted under the 2015 Inducement Plan shall be determined by the administrator of the 2015 Inducement Plan, which is the compensation committee of the Company’s board of directors, and shall not be less than 100% of the fair market value of the Company’s common stock on the date the option is granted. For holders of more than 10% of the Company’s total combined voting power of all classes of stock, incentive stock options may not be granted at less than 110% of the fair market value of the Company’s common stock on the date of grant and for a term not to exceed five years. The exercise price of each option to be granted under the 2014 Plan shall be determined by the administrator of the 2014 Plan, which is the Company’s board of directors or the compensation committee thereof, and shall not be less than 100% of the fair market value of the Company’s common stock on the date the option is granted. Fair Value of Equity Awards The Company utilizes the Black-Scholes option pricing model to value awards under its plans. Key valuation assumptions include: • Volatility – • Risk-Free Interest Rate – • Dividend Yield – • Expected Life of the Option Term – Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company assesses the forfeiture rate on an annual basis and revises the rate when deemed necessary. The weighted average assumptions used to estimate the fair value of stock option grants were as follows: Year ended December 31, 2015 2014 2013 Volatility 69 % 65 % 59 % Expected life of option 6.2 years 6.0 years 6.6 years Risk free interest rate 1.7 % 1.8 % 2.0 % Dividend yield — % — % — % The estimated weighted-average fair value of stock options granted during fiscal 2015, 2014 and 2013 was $7.25, $4.72 and $2.63 per share, respectively. Restricted Stock Units In 2015, the Company issued 90,000 restricted stock units (“RSUs”) to employees with vesting to occur on either the fourth or fifth anniversary of the grant date. All of these RSUs were outstanding and subject to future vesting as of December 31, 2015. Stock-Based Compensation The following table summarizes stock-based compensation expense for all equity awards to employees and non-employees during the periods presented ( in thousands Year ended December 31, 2015 2014 2013 Included in research and development $ 2,576 $ 896 $ 240 Included in general and administrative 2,769 1,387 130 Total $ 5,345 $ 2,283 $ 370 Unrecognized stock-based compensation expense related to unvested awards granted under the Company’s equity incentive plans totaled $23.0 million as of December 31, 2015, and is expected to be recognized over a weighted-average period of 3.2 years.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	12. INCOME TAXES The Company is subject to taxes in the United States as well as certain state tax jurisdictions. The Company is not currently under examination by any federal or state jurisdictions. The tax years from 2011 through 2015 remain open to examination by the major taxing jurisdictions to which the Company is subject. A reconciliation of the statutory federal income tax provision to the actual income tax provision is as follows ( in thousands Year ended December 31, 2015 2014 2013 Expected income tax benefit at federal statutory rate $ (31,436 ) $ (13,597 ) $ (4,832 ) State income tax benefit, net of federal benefit (5,438 ) (2,245 ) (758 ) Research credits (1,854 ) (1,118 ) (204 ) Intangible related to asset acquisition (1,247 ) — — Uncertain tax positions 1,386 — — Other 13 162 362 Change in valuation allowance 38,576 16,798 5,432 Income tax expense (benefit) $ — $ — $ — The following table summarizes the changes in the amount of the Company’s unrecognized tax benefits ( in thousands Year ended December 31, 2015 2014 2013 Beginning balance $ — $ — $ — Increase (decrease) for prior year tax positions 2,100 — — Increase (decrease) for current year tax positions — — — Total unrecognized tax benefits $ 2,100 $ — $ — Included in the balance of unrecognized tax benefits at December 31, 2015 is $2.1 million that, if recognized, would not impact our income tax benefit or effective tax rate as long as our deferred tax asset remains subject to a full valuation allowance. We do not expect any significant increases or decreases to our unrecognized tax benefits within the next 12 months. As of December 31, 2015 and 2014, a non-current deferred tax asset of approximately $62.6 million and $23.9 million, respectively, had been recognized for the temporary differences primarily related to federal and state net operating losses and research and development credits. Realization of deferred tax assets is dependent upon future earnings, if any, the timing and amount of which are uncertain. Accordingly, the deferred tax assets have been fully offset by a valuation allowance. The following summarizes the significant components of the Company’s deferred tax assets ( in thousands December 31, 2015 2014 Net operating loss carryforwards $ 35,131 $ 13,091 Tax credit carryforwards 3,224 1,361 Stock-based compensation 2,848 848 Accrued compensation 1,485 62 Intangible assets recognized for tax purposes 13,143 7,566 In process research and development charge 5,865 — Other, net 846 1,006 Total deferred tax assets 62,542 23,934 Deferred tax liabilities (depreciation) (1,060 ) (1,106 ) Valuation allowance (61,482 ) (22,828 ) Net deferred tax assets $ — $ — At December 31, 2015, the Company had unused federal and state net operating losses of approximately $92.3 million and $91.7 million, respectively. The federal and state net operating loss carryforwards will begin to expire in 2031. Approximately $1.0 million of the net operating loss carryforwards relate to excess tax deductions for stock compensation, the income tax benefit of which will be recorded as additional paid-in capital if and when realized. At December 31, 2015, the Company also had federal and state research tax credit carryforwards of approximately $1.8 million and $2.1 million, respectively. The federal carryforwards begin to expire in 2031, while the state carryforwards have no expiration. The utilization of the Company’s net operating loss and tax credit carryforwards to offset future taxable income may be subject to an annual limitation as a result of ownership changes that have occurred previously or may occur in the future. The Tax Reform Act of 1986 (the “Act”) limits a company’s ability to utilize certain net operating loss and tax credit carryforwards in the event of a cumulative change in ownership in excess of 50% as defined in the Act. These financial statements do not contain any adjustment relating to such potential limitations. The Company’s practice is to recognize interest and/or penalties related to income tax matters as income tax expense. The Company has not recognized any interest or penalties related to income taxes in any of the periods presented.

Quarterly Data (unaudited)

Quarterly Data (unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Quarterly Data (unaudited)	13. QUARTERLY DATA ( unaudited ) The following quarterly financial data, in the opinion of management, reflects all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of results for the periods presented (in thousands, except per share amounts): Year Ended December 31, 2015 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ — $ — $ — $ — Research and development expenses (1)(2) $ 20,215 $ 8,796 $ 10,432 $ 34,068 Total operating expenses $ 22,982 $ 12,651 $ 14,289 $ 40,658 Net loss $ (23,507 ) $ (13,120 ) $ (14,621 ) $ (41,210 ) Net loss per share – basic and diluted $ (1.15 ) $ (0.51 ) $ (0.49 ) $ (1.32 ) Year Ended December 31, 2014 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ — $ 150 $ — $ — Research and development expenses (3)(4) $ 2,183 $ 3,576 $ 8,622 $ 16,124 Total operating expenses $ 3,945 $ 5,615 $ 10,845 $ 19,606 Net loss $ (4,107 ) $ (5,423 ) $ (10,703 ) $ (19,757 ) Net loss per share – basic and diluted $ (0.28 ) $ (0.28 ) $ (0.55 ) $ (1.01 ) (1) First quarter 2015 results include an up-front payment of $0.9 million and a non-cash charge of approximately $11.9 million based on the value of 1,500,000 shares of common stock exchanged for the assets acquired from Teva (see Note 7). (2) Fourth quarter 2015 results include an up-front payment of $2.0 million and a non-cash charge of approximately $13.4 million based on the value of 1,213,000 shares of common stock exchanged for the rights acquired from Lilly for the Company’s taladegib product candidate (see Note 8). (3) Third quarter 2014 results include the upfront license fee of approximately $3.5 million paid to NMS for rights to the Company’s RXDX-103 and RXDX-104 product candidates (see Note 8). (4) Fourth quarter 2014 results include a milestone payment of approximately $10.0 million paid to NMS in connection with the Company’s entrectinib product candidate (see Note 8).

Subsequent Event

Subsequent Event	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Event	14. SUBSEQUENT EVENT On February 23, 2016, the Company announced that it was discontinuing future development activities relating to its RXDX-103, RXDX-107 and RXDX-108 drug development programs. These changes would not have had a significant impact on the Company’s financial position as of December 31, 2015, nor on its results of operations for the year then ended.

Organization (Policies)

Organization (Policies)	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of Operations	Organization and Nature of Operations Ignyta, Inc. (“Ignyta” or the “Company”) is incorporated in the state of Delaware and was founded in 2011 (with the name “NexDx, Inc.”). The Company changed its name to “Ignyta, Inc.” on October 8, 2012. The Company is a precision oncology biotechnology company. Its goal is not just to shrinking tumors, but to eradicate residual disease – the source of cancer relapse and recurrence – in precisely defined patient populations. The Company is pursuing an integrated therapeutic (Rx) and companion diagnostic (Dx) strategy for treating cancer patients. Its Rx efforts are focused on discovering, in-licensing or acquiring, then developing and commercializing molecularly targeted therapies that, sequentially or in combination, are foundational for eradicating residual disease. Its Dx efforts aim to pair these product candidates with biomarker-based companion diagnostics that are designed to precisely identify, at the molecular level, the patients who are most likely to benefit from the therapies it develops. On October 31, 2013, the Company merged with and into IGAS Acquisition Corp., a wholly owned subsidiary of Ignyta, Inc., a Nevada corporation previously named “Infinity Oil & Gas Company” (“Parent”), formerly a “shell company” under applicable rules of the Securities and Exchange Commission (the “SEC”). The Company changed its name to Ignyta Operating, Inc. in connection with this merger, and it survived the merger as a wholly owned subsidiary of Parent. In the merger, Parent acquired the business of the Company and continued the business operations of the Company. The merger was accounted for as a reverse merger and recapitalization, with the Company as the acquirer and Parent as the acquired company for financial reporting purposes. As a result, the assets and liabilities and the operations that are reflected in the historical financial statements prior to the merger are those of the Company and are recorded at the historical cost basis of the Company, and the financial statements after completion of the merger will include the assets and liabilities of Parent and the Company, the historical operations of the Company and the operations of the combined enterprise of Parent and the Company from and after the closing date of the merger. On June 12, 2014, Parent merged with and into the Company, with the Company surviving the merger and changing its name to “Ignyta, Inc.” (the “Reincorporation Merger”). This Reincorporation Merger had no material impact on the accounting of the Company. Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business as one operating segment.
Liquidity	Liquidity The Company had negative cash flow from operations of approximately $50.8 million during 2015 and, as of December 31, 2015, had an accumulated deficit of approximately $148.0 million. The Company is focused primarily on its development programs, and management believes such activities will result in the continued incurrence of significant research and development and other expenses related to those programs. The Company expects that it will need additional capital to further fund development of, and seek regulatory approvals for, its product candidates, and begin to commercialize any approved products. If the clinical trials for any of the Company’s products fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of its product candidates, if approved, fails to achieve market acceptance, the Company may never become profitable. Even if the Company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. The Company intends to cover its future operating expenses through cash on hand and through additional financing from existing and prospective investors. The Company cannot be sure that additional financing will be available when needed or that, if available, financing will be obtained on terms favorable to the Company or to its stockholders. As of December 31, 2015, the Company had cash, cash equivalents and available-for-sale securities totaling $172.1 million. While the Company expects that its existing cash, cash equivalents and available-for-sale securities will enable it to fund its operations and capital expenditure requirements for at least the next twelve months, having insufficient funds may require the Company to delay, reduce, limit or terminate some or all of its development programs or future commercialization efforts or grant rights to develop and market product candidates that it would otherwise prefer to develop and market on its own. Failure to obtain adequate financing could eventually adversely affect the Company’s ability to operate as a going concern. If the Company raises additional funds from the issuance of equity securities, substantial dilution to its existing stockholders would likely result. If the Company raises additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict its ability to operate its business.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles, or GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities. Significant estimates used in preparing the financial statements include those assumed in estimating expenses for the Company’s pre-clinical studies and clinical trials, computing the valuation allowance on deferred tax assets, calculating stock-based compensation expense and for determining the value of leased property during the construction period for which the Company has been deemed the accounting owner. Actual results could differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of 90 days or less when purchased to be cash equivalents. Cash equivalents primarily represent amounts invested in money market funds whose cost equals market value.
Investment Securities	Investment Securities Investment securities consist of government and government agency obligations, corporate notes and bonds and commercial paper. The Company classifies its investment securities as available-for-sale at the time of purchase. All investment securities are recorded at estimated fair value. Unrealized gains and losses for available-for-sale investment securities are included in accumulated other comprehensive income or loss, a component of stockholders’ equity. The Company evaluates its investment securities as of each balance sheet date to assess whether those with unrealized loss positions are other-than-temporarily impaired. Impairments are considered to be other-than-temporary if they are related to deterioration in credit risk or if it is likely that the Company will sell the securities before the recovery of its cost basis. Realized gains and losses and declines in value judged to be other-than-temporary are determined based on the specific identification method. No other-than-temporary impairment charges have been recognized since inception.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Financial assets and liabilities are measured at fair value, which is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The Company’s financial instruments consist of cash and cash equivalents, investment securities, prepaid expenses and other assets, accounts payable, accrued expenses, and notes payable. The valuation of assets and liabilities is subject to fair value measurements using a three tiered approach, and fair value measurement is classified and disclosed in one of the following categories: Level 1: Quoted prices in active markets for identical assets or liabilities; Level 2: Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; or Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Fair value estimates of these instruments at a specific point in time are made based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of judgment and therefore cannot be determined with precision. The Company reports its available-for-sale securities at their estimated fair values based on quoted market prices for identical or similar instruments. The book values of cash and cash equivalents, prepaid expenses and other assets, accounts payable, accrued expenses, notes payable and other liabilities are reasonable estimates of fair value because of the short-term nature of these items
Credit Risk	Credit Risk Cash is invested in accordance with a policy approved by the Company’s board of directors which specifies the categories, allocations, and ratings of securities that the Company may consider for investment. Management does not believe that the Company’s cash, cash equivalents and available-for-sale investment securities have significant risk of default or illiquidity. This determination is based on discussions with the Company’s treasury managers and a review of the Company’s holdings. While the Company believes that its cash, cash equivalents and available-for-sale investment securities are well diversified and do not contain excessive risk, the Company cannot provide absolute assurance that its investments will not be subject to future adverse changes in market value. The Company maintains cash balances at various financial institutions. Accounts at these institutions are secured by the Federal Deposit Insurance Corporation. At times these balances exceed federally insured limits. The Company has not experienced any losses in such accounts. With respect to the Company’s cash equivalents and available-for-sale investment securities, the primary exposure to market risk is interest rate sensitivity. This means that a change in prevailing interest rates may cause the value of the investment to fluctuate. For example, if the Company purchases a security that was issued with a fixed interest rate and the prevailing interest rate later rises, the value of this investment will probably decline. Currently, the Company’s holdings are in money market funds and available-for-sale investment securities, and therefore this interest rate risk is minimal. To minimize interest rate risk going forward, the Company intends to continue to maintain its portfolio of cash, cash equivalents and available-for-sale investment securities in a variety of securities consisting of money market funds and debt securities, all with various maturities. In general, money market funds are not subject to market risk because the interest paid on such funds fluctuates with the prevailing interest rate. The Company also attempts to time the maturities of its investments to correspond with expected cash needs, allowing it to avoid realizing any potential losses from having to sell securities prior to their maturities.
Property and Equipment	Property and Equipment Property and equipment are recorded at cost. Depreciation is computed using the straight-line method over the estimated useful lives of the related assets, which generally range from three to seven years, or, in the case of leasehold improvements, over the lesser of the useful life of the related asset or the lease term. The Company reviews property and equipment for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. An impairment loss would be recognized when estimated future undiscounted cash flows relating to the asset are less than its carrying amount. An impairment loss is measured as the amount by which the carrying amount of an asset exceeds its fair value. To date, the Company has not experienced any impairment losses on its property and equipment. The Company establishes assets and corresponding financing liabilities for the construction costs incurred under build-to-suit lease arrangements when it is determined that the Company takes construction risks during the construction period and is deemed the accounting owner of the property during construction. At the end of the construction period, the Company assesses whether the arrangement qualifies for sales recognition under the sale-leaseback accounting guidance in ASC 840.
Clinical Trial and Pre-Clinical Study Accruals	Clinical Trial and Pre-Clinical Study Accruals The Company makes estimates of accrued expenses as of each balance sheet date in its financial statements based on the facts and circumstances known to it at that time. Accrued expenses for pre-clinical studies and clinical trials are based on estimates of costs incurred and fees that may be associated with services provided by contract research organizations, clinical trial investigational sites, and other related vendors. Payments under certain contracts with such parties depend on factors such as successful enrollment of patients, site initiation and the completion of milestones. In accruing service fees, management estimates the time period over which services will be performed and the level of effort to be expended in each period. If possible, the Company obtains information regarding unbilled services directly from these service providers. However, the Company may be required to estimate these services based on other information available to it. If the Company underestimates or overestimates the activity or fees associated with a study or service at a given point in time, adjustments to research and development expenses may be necessary in future periods. Historically, estimated accrued liabilities have approximated actual expense incurred. Subsequent changes in estimates may result in a material change in the Company’s accruals.
Income Taxes	Income Taxes Deferred income taxes are recognized for the tax consequences in future years of differences between the tax basis of assets and liabilities and their financial reporting amounts at each year end based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. Income tax expense is the combination of the tax payable for the year and the change during the year in deferred tax assets and liabilities. The Company follows the accounting guidance on accounting for uncertainty in income taxes. The guidance prescribes a recognition threshold and measurement attribute criteria for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities based on the technical merits of the position.
Research and Development	Research and Development Costs incurred in connection with research and development activities are expensed as incurred. Research and development expenses consist of (i) external research and development expenses incurred under arrangements with third parties, such as contract research organizations, investigational sites and consultants; (ii) employee-related expenses, including salaries, benefits, travel and stock compensation expense; (iii) the cost of acquiring, developing and manufacturing clinical study materials; (iv) facilities and other expenses, which include direct and allocated expenses for rent and maintenance of facilities and laboratory and other supplies, and (v) license fees and other expenses relating to the acquisition of rights to our development programs. The Company enters into consulting, research and other agreements with commercial firms, researchers, universities and others for the provision of goods and services. Under such agreements, the Company may pay for services on a monthly, quarterly, project or other basis. Such arrangements are generally cancellable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided to the Company by its clinical sites and vendors and other information. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. In certain circumstances, the Company is required to make advance payments to vendors for goods or services that will be received in the future for use in research and development activities. In such circumstances, the advance payments are deferred and are expensed when the activity has been performed or when the goods have been received.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation cost for equity awards to employees and members of the Company’s board of directors is measured at the grant date, based on the calculated fair value of the award using the Black-Scholes option-pricing model, and is recognized as an expense, under the straight-line method, over the requisite service period (generally the vesting period of the equity grant). Stock options issued to non-employees are accounted for at their estimated fair values determined using the Black-Scholes option-pricing model. The fair value of options granted to non-employees is re-measured as they vest, and the resulting increase in value, if any, is recognized as an expense during the period the related services are rendered. Restricted stock issued to non-employees is accounted for at its estimated fair value as it vests.
Comprehensive Income	Comprehensive Income Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company is required to record all components of comprehensive income (loss) in the financial statements in the period in which they are recognized. Net income (loss) and other comprehensive income (loss), including unrealized gains and losses on available-for-sale investments, are reported net of their related tax effect, to arrive at comprehensive income (loss).
Net Loss per Share	Net Loss per Share Basic and diluted loss per common share have been computed by dividing the losses applicable to common stock by the weighted average number of common shares outstanding. The Company’s basic and fully diluted loss per common share calculations are the same since the increased number of shares that would be included in the diluted calculation from the assumed exercise of stock equivalents would be anti-dilutive to the net loss in each of the years shown in the financial statements. The calculations of net loss per share excluded potentially dilutive securities (consisting of outstanding options, warrants, restricted stock and restricted stock units) of approximately 5.4 million and 3.1 million shares as of December 31, 2015 and 2014, respectively.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In January 2016, the FASB issued an accounting standard update, or ASU, which addresses certain aspects of recognition, measurement, presentation and disclosure of certain assets and liabilities in financial statements. This guidance will be effective in the first quarter of fiscal year 2018 and early adoption is not permitted. The Company is currently evaluating the impact that this guidance will have on its financial statements. In November 2015, the FASB issued an ASU which requires that deferred tax assets and liabilities be classified as noncurrent rather than being separated into current and noncurrent components. This new guidance will be effective in the first quarter of fiscal 2017. This guidance is not expected to have a material impact on our financial statements. In April 2015, the FASB issued an accounting standard update which requires presentation of debt issuance costs as a direct deduction from the carrying amount of a recognized debt liability on the balance sheet, consistent with the treatment of debt discounts. The update does not change the guidance on the recognition and measurement of debt issuance costs. The Company intends to adopt this guidance at the beginning of its first quarter of fiscal year 2016. At the time of adoption, the Company will reclassify debt issuance costs to a liability as a direct deduction from the carrying value of the debt, consistent with the presentation of a debt discount. The adoption of this update is not expected to have a material impact on the Company’s financial statements. In August 2014, the FASB issued an ASU that requires management to evaluate whether there are conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern, and to provide certain disclosures when it is probable that the entity will be unable to meet its obligations as they become due within one year after the date that the financial statements are issued. The Company intends to adopt this guidance at the beginning of its first quarter of fiscal year 2016. Since this guidance is primarily around certain disclosures in the financial statements, the Company anticipates no impact on its financial position or results of operations. In May 2014, the FASB issued an ASU that supersedes or replaces nearly all revenue recognition guidance. The new guidance establishes a new control-based revenue recognition model, changes the basis for deciding when revenue is recognized over time or at a point in time and will expand disclosures about revenue. Companies may use either a full retrospective or a modified retrospective approach to adopt this guidance. The Company is evaluating which transition approach to use and its impact, if any, on its financial statements. This ASU is effective for the fiscal year beginning January 1, 2019, and early adoption is not permitted.
Reclassifications	Reclassifications Certain reclassifications have been made to prior year amounts to conform to the current year presentation. These changes had no impact on the Company’s total assets or reported net loss.
Fair Value Measurements	The Company holds available-for-sale securities that consist of highly liquid, investment grade debt securities. The Company determines the fair value of its available-for-sale securities based upon one or more valuations reported by its investment accounting and reporting service provider. The investment service provider values the securities using a hierarchical security pricing model that relies primarily on valuations provided by an industry-recognized valuation service. Such valuations may be based on trade prices in active markets for identical assets or liabilities (Level 1 inputs) or valuation models using inputs that are observable either directly or indirectly (Level 2 inputs), such as quoted prices for similar assets or liabilities, yield curves, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments or debt, and broker and dealer quotes, as well as other relevant economic measures. The fair value of cash, cash equivalents and available-for-sale investment securities were as follows ( in thousands As of December 31, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 46,383 $ — $ — $ 46,383 $ 6,346 $ — $ — $ 6,346 Short-term investments: Commercial paper — 7,992 — 7,992 — 3,896 — 3,896 Corporate debt securities — 70,426 — 70,426 — 59,305 — 59,305 U.S. government and U.S. government agency obligations 7,002 — — 7,002 — — — — Total short-term investments 7,002 78,418 — 85,420 — 63,201 — 63,201 Long-term investments: Corporate debt securities — 24,356 — 24,356 — 7,087 — 7,087 U.S. government and U.S. government agency obligations 15,990 — — 15,990 — — — — Total long-term investments 15,990 24,356 — 40,346 — 7,087 — 7,087 Total assets measured at fair value $ 69,375 $ 102,774 $ — $ 172,149 $ 6,346 $ 70,288 $ — $ 76,634

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2015
Investments Schedule [Abstract]
Summary of Available for Sale Investment Held by the Company	The following tables summarize the available-for-sale investments held by the Company as of the dates below ( in thousands As of December 31, 2015 Amortized Cost Gross Gross Fair Available-for-sale investment securities: Commercial paper, short-term $ 7,992 $ — $ — $ 7,992 Corporate debt securities, short-term 70,505 1 (80 ) 70,426 Corporate debt securities, long-term 24,454 2 (100 ) 24,356 U.S. government and agency obligations, short-term 7,009 — (7 ) 7,002 U.S. government and agency obligations, long-term 16,055 — (65 ) 15,990 Total $ 126,015 $ 3 $ (252 ) $ 125,766 As of December 31, 2014 Amortized Cost Gross Gross Fair Available-for-sale investment securities: Commercial paper, short-term $ 3,896 $ — $ — $ 3,896 Corporate debt securities, short-term 59,343 — (38 ) 59,305 Corporate debt securities, long-term 7,102 — (15 ) 7,087 Total $ 70,341 $ — $ (53 ) $ 70,288

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Cash, Cash Equivalents and Available-for-Sale Investment Securities	The fair value of cash, cash equivalents and available-for-sale investment securities were as follows ( in thousands As of December 31, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 46,383 $ — $ — $ 46,383 $ 6,346 $ — $ — $ 6,346 Short-term investments: Commercial paper — 7,992 — 7,992 — 3,896 — 3,896 Corporate debt securities — 70,426 — 70,426 — 59,305 — 59,305 U.S. government and U.S. government agency obligations 7,002 — — 7,002 — — — — Total short-term investments 7,002 78,418 — 85,420 — 63,201 — 63,201 Long-term investments: Corporate debt securities — 24,356 — 24,356 — 7,087 — 7,087 U.S. government and U.S. government agency obligations 15,990 — — 15,990 — — — — Total long-term investments 15,990 24,356 — 40,346 — 7,087 — 7,087 Total assets measured at fair value $ 69,375 $ 102,774 $ — $ 172,149 $ 6,346 $ 70,288 $ — $ 76,634

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Property and Equipment	Property and equipment consisted of the following ( in thousands As of December 31, 2015 As of December 31, 2014 Manufacturing and lab equipment $ 6,941 $ 3,838 Leasehold improvements 2,349 2,327 Computer and office equipment 1,145 750 Construction in process (see below) 11,000 — Property and equipment at cost 21,435 6,915 Less accumulated depreciation and amortization (2,671 ) (634 ) Property and equipment, net $ 18,764 $ 6,281
Schedule of Accrued Expenses and Other Liabilities	The following table summarizes major classes of accrued expenses and other current liabilities ( in thousands As of December 31, 2015 As of December 31, 2014 Contracted clinical trial services fees and related costs $ 5,766 $ 1,971 Research and development services 1,763 355 Personnel and related costs 3,844 1,828 Other liabilities 2,487 776 Total $ 13,860 $ 4,930
Schedule of Other Long-term Liabilities	Other long-term liabilities consisted of the following ( in thousands As of December 31, 2015 As of December 31, 2014 Deferred rent, net of current portion $ 70 $ 2,074 Final loan fee obligation to lender (see note 6) 930 630 Leased facility financing obligation (see below) 11,000 — Total $ 12,000 $ 2,704

Notes Payable (Tables)

Notes Payable (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Future Minimum Principal Payments on Notes Payable	Future minimum principal payments under the Company’s note payable are as follows ( in thousands Year ending December 31, Minimum Payments 2016 $ 6,889 2017 10,333 2018 10,333 2019 3,445 Total $ 31,000

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Non-cancellable Future Minimum Payments Under Capital and Operating Lease	The Company’s non-cancellable future minimum annual lease payments under its capital and operating leases for the years ending after December 31, 2015 are as follows (in thousands): Capital Operating Leases Leases 2016 $ 194 $ 1,541 2017 167 2,852 2018 — 4,482 2019 — 4,500 2020 — 4,635 Thereafter — 8,435 Total minimum lease payments 361 $ 26,445 Less amount representing interest (16 ) Present value of obligations under capital leases 345 Less current portion (181 ) Long-term capital lease obligations $ 164

Equity Awards (Tables)

Equity Awards (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Equity Incentive Plan Activity and Other Related Information	A summary of the Company’s equity incentive plan activity and other related information is as follows: Options Weighted- Weighted- Aggregate Balance at December 31, 2014 2,991,655 $ 6.67 9.21 $ 2,482,181 Granted 2,695,991 11.63 Exercised (77,477 ) 5.66 Forfeited (359,229 ) 7.74 Balance at December 31, 2015 5,250,940 $ 9.16 8.83 $ 24,565,711 Exercisable at December 31, 2015 1,206,105 $ 6.07 8.05 $ 8,837,446
Assumptions Used to Estimate Fair Value of Option Granted	The weighted average assumptions used to estimate the fair value of stock option grants were as follows: Year ended December 31, 2015 2014 2013 Volatility 69 % 65 % 59 % Expected life of option 6.2 years 6.0 years 6.6 years Risk free interest rate 1.7 % 1.8 % 2.0 % Dividend yield — % — % — %
Summary of Stock-Based Compensation Expense for Equity Awards to Employees and Non-Employees	The following table summarizes stock-based compensation expense for all equity awards to employees and non-employees during the periods presented ( in thousands Year ended December 31, 2015 2014 2013 Included in research and development $ 2,576 $ 896 $ 240 Included in general and administrative 2,769 1,387 130 Total $ 5,345 $ 2,283 $ 370

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Reconciliation of Statutory Federal Income Tax Provision to Actual Income Tax Provision	A reconciliation of the statutory federal income tax provision to the actual income tax provision is as follows ( in thousands Year ended December 31, 2015 2014 2013 Expected income tax benefit at federal statutory rate $ (31,436 ) $ (13,597 ) $ (4,832 ) State income tax benefit, net of federal benefit (5,438 ) (2,245 ) (758 ) Research credits (1,854 ) (1,118 ) (204 ) Intangible related to asset acquisition (1,247 ) — — Uncertain tax positions 1,386 — — Other 13 162 362 Change in valuation allowance 38,576 16,798 5,432 Income tax expense (benefit) $ — $ — $ —
Summary of Unrecognized Tax Benefits	The following table summarizes the changes in the amount of the Company’s unrecognized tax benefits ( in thousands Year ended December 31, 2015 2014 2013 Beginning balance $ — $ — $ — Increase (decrease) for prior year tax positions 2,100 — — Increase (decrease) for current year tax positions — — — Total unrecognized tax benefits $ 2,100 $ — $ —
Summary of Significant Components of Company's Deferred Tax Assets	The following summarizes the significant components of the Company’s deferred tax assets ( in thousands December 31, 2015 2014 Net operating loss carryforwards $ 35,131 $ 13,091 Tax credit carryforwards 3,224 1,361 Stock-based compensation 2,848 848 Accrued compensation 1,485 62 Intangible assets recognized for tax purposes 13,143 7,566 In process research and development charge 5,865 — Other, net 846 1,006 Total deferred tax assets 62,542 23,934 Deferred tax liabilities (depreciation) (1,060 ) (1,106 ) Valuation allowance (61,482 ) (22,828 ) Net deferred tax assets $ — $ —

Quarterly Data (unaudited) (Tab

Quarterly Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Data	The following quarterly financial data, in the opinion of management, reflects all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of results for the periods presented (in thousands, except per share amounts): Year Ended December 31, 2015 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ — $ — $ — $ — Research and development expenses (1)(2) $ 20,215 $ 8,796 $ 10,432 $ 34,068 Total operating expenses $ 22,982 $ 12,651 $ 14,289 $ 40,658 Net loss $ (23,507 ) $ (13,120 ) $ (14,621 ) $ (41,210 ) Net loss per share – basic and diluted $ (1.15 ) $ (0.51 ) $ (0.49 ) $ (1.32 ) Year Ended December 31, 2014 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ — $ 150 $ — $ — Research and development expenses (3)(4) $ 2,183 $ 3,576 $ 8,622 $ 16,124 Total operating expenses $ 3,945 $ 5,615 $ 10,845 $ 19,606 Net loss $ (4,107 ) $ (5,423 ) $ (10,703 ) $ (19,757 ) Net loss per share – basic and diluted $ (0.28 ) $ (0.28 ) $ (0.55 ) $ (1.01 ) (1) First quarter 2015 results include an up-front payment of $0.9 million and a non-cash charge of approximately $11.9 million based on the value of 1,500,000 shares of common stock exchanged for the assets acquired from Teva (see Note 7). (2) Fourth quarter 2015 results include an up-front payment of $2.0 million and a non-cash charge of approximately $13.4 million based on the value of 1,213,000 shares of common stock exchanged for the rights acquired from Lilly for the Company’s taladegib product candidate (see Note 8). (3) Third quarter 2014 results include the upfront license fee of approximately $3.5 million paid to NMS for rights to the Company’s RXDX-103 and RXDX-104 product candidates (see Note 8). (4) Fourth quarter 2014 results include a milestone payment of approximately $10.0 million paid to NMS in connection with the Company’s entrectinib product candidate (see Note 8).

Organization - Additional Infor

Organization - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)Segment	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segment | Segment	1
Net cash used in operating activities	$ (50,800)	$ (32,488)	$ (13,075)
Accumulated deficit	(148,021)	$ (55,563)
Cash, cash equivalents and available-for-sale securities total	$ 172,100

Summary of Significant Accoun31

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) shares in Millions	12 Months Ended		52 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015
Accounting Policies [Line Items]
Other-than-temporary impairment charges			$ 0
Antidilutive securities excluded from computation of earnings per share	5.4	3.1
Minimum [Member]
Accounting Policies [Line Items]
Estimated useful lives of property and equipment	3 years
Maximum [Member]
Accounting Policies [Line Items]
Estimated useful lives of property and equipment	7 years

Investment Securities - Summary

Investment Securities - Summary of Available for Sale Investment Held by the Company (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	$ 126,015	$ 70,341
Available-for-sale investment securities, Gross Unrealized Gains	3
Available-for-sale investment securities, Gross Unrealized Losses	(252)
Available-for-sale investment securities, Fair Market Value	125,766	70,288
Commercial Paper [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	7,992	3,896
Available-for-sale investment securities, Fair Market Value	7,992	3,896
Corporate Debt Securities [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	70,505	59,343
Available-for-sale investment securities, Gross Unrealized Gains	1
Available-for-sale investment securities, Gross Unrealized Losses	(80)
Available-for-sale investment securities, Fair Market Value	70,426	59,305
Corporate Debt Securities [Member] | Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	24,454	7,102
Available-for-sale investment securities, Gross Unrealized Gains	2
Available-for-sale investment securities, Gross Unrealized Losses	(100)
Available-for-sale investment securities, Fair Market Value	24,356	$ 7,087
U.S. Government and Agency Obligations [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	7,009
Available-for-sale investment securities, Gross Unrealized Losses	(7)
Available-for-sale investment securities, Fair Market Value	7,002
U.S. Government and Agency Obligations [Member] | Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	16,055
Available-for-sale investment securities, Gross Unrealized Losses	(65)
Available-for-sale investment securities, Fair Market Value	$ 15,990

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value of Cash, Cash Equivalents and Available-for-Sale Investment Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 46,383	$ 6,346
Total assets measured at fair value	172,149	76,634
Short-Term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	85,420	63,201
Short-Term Investments [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	7,992	3,896
Short-Term Investments [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	70,426	59,305
Short-Term Investments [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	7,002
Long-Term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	40,346	7,087
Long-Term Investments [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	24,356	7,087
Long-Term Investments [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	15,990
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	46,383	6,346
Total assets measured at fair value	69,375	6,346
Level 1 [Member] | Short-Term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	7,002
Level 1 [Member] | Short-Term Investments [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	7,002
Level 1 [Member] | Long-Term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	15,990
Level 1 [Member] | Long-Term Investments [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	15,990
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	102,774	70,288
Level 2 [Member] | Short-Term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	78,418	63,201
Level 2 [Member] | Short-Term Investments [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	7,992	3,896
Level 2 [Member] | Short-Term Investments [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	70,426	59,305
Level 2 [Member] | Long-Term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	24,356	7,087
Level 2 [Member] | Long-Term Investments [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 24,356	$ 7,087

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Manufacturing and lab equipment	$ 6,941	$ 3,838
Leasehold improvements	2,349	2,327
Computer and office equipment	1,145	750
Construction in process	11,000
Property and equipment at cost	21,435	6,915
Less accumulated depreciation and amortization	(2,671)	(634)
Property and equipment, net	$ 18,764	$ 6,281

Balance Sheet Details - Additio

Balance Sheet Details - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Oct. 31, 2015ft²	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Property, Plant and Equipment [Line Items]
Area of leased space | ft²	95,146
Estimated fair value of leased financing obligation		$ 11,000,000
Level 3 [Member]
Property, Plant and Equipment [Line Items]
Estimated fair value of leased financing obligation		10,900,000
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Capital leased assets gross		636,000
Capital leased assets net		144,000	$ 17,000
Depreciation		$ 127,000	$ 17,000

Balance Sheet Details - Sched36

Balance Sheet Details - Schedule of Accrued Expenses and Other Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accrued Liabilities, Current [Abstract]
Contracted clinical trial services fees and related costs	$ 5,766	$ 1,971
Research and development services	1,763	355
Personnel and related costs	3,844	1,828
Other liabilities	2,487	776
Total	$ 13,860	$ 4,930

Balance Sheet Details - Sched37

Balance Sheet Details - Schedule of Other Long-term Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Other Liabilities [Abstract]
Deferred rent, net of current portion	$ 70	$ 2,074
Final loan fee obligation to lender	930	630
Leased facility financing obligation	11,000
Total	$ 12,000	$ 2,704

Notes Payable - Additional Info

Notes Payable - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2015USD ($)shares
Debt Instrument [Line Items]
Amount of indebtedness incurred	$ 31,000
New Loan Agreement [Member] | Silicon Valley Bank [Member] | Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Amount of indebtedness incurred	$ 31,000,000
Interest on borrowings, per-annum rate	8.60%
Principal and interest payment period	36 months
New loan agreement maturity date	Apr. 30, 2019
Final loan fee recorded as debt discount	$ 930,000
Prepayment fee percentage on principal loan prepaid	1.00%
Contingency payments default interest rate	11.60%
New Loan Agreement [Member] | Common Stock Warrant [Member]
Debt Instrument [Line Items]
Warrant to purchase stock, shares | shares	53,281

Notes Payable - Future Minimum

Notes Payable - Future Minimum Principal Payments on Notes Payable (Detail)	Dec. 31, 2015USD ($)
Debt Disclosure [Abstract]
2,016	$ 6,889
2,017	10,333
2,018	10,333
2,019	3,445
Total	$ 31,000

Asset Acquisition - Additional

Asset Acquisition - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Mar. 17, 2015	Jun. 30, 2015	Mar. 31, 2015	Mar. 31, 2014	Nov. 30, 2013	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Noncash or Part Noncash Acquisitions [Line Items]
In-process research and development charge associated with asset acquisition						$ 11,900	$ 11,880
Additional shares issued in subscription agreement					9,010,238
Cephalon Inc [Member]
Noncash or Part Noncash Acquisitions [Line Items]
Additional shares issued in subscription agreement			4,158,750
Liquidated damages in percent of aggregate purchase price	1.00%
Aggregate cap in percent for liquidated damages	10.00%
Cephalon Inc [Member] | Drug Development Supplies [Member]
Noncash or Part Noncash Acquisitions [Line Items]
Payments to acquire drug development supplies						$ 900
Common Stock [Member]
Noncash or Part Noncash Acquisitions [Line Items]
Additional shares issued in subscription agreement		4,285,714		6,031,750			9,944,464	6,031,750	9,010,238
Common Stock [Member] | Cephalon Inc [Member]
Noncash or Part Noncash Acquisitions [Line Items]
Additional shares issued in subscription agreement	1,500,000
Share price	$ 10
Unregistered Common Stock [Member] | Cephalon Inc [Member]
Noncash or Part Noncash Acquisitions [Line Items]
Stock issued for purchase of asset	1,500,000					1,500,000

License Agreements - Additional

License Agreements - Additional Information (Detail) - USD ($)	Nov. 06, 2015	Aug. 04, 2014	Nov. 06, 2013	Nov. 30, 2015	Dec. 31, 2014	Nov. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2015
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License agreement term										5 years
Net proceeds from issuance of shares						$ 51,000,000
RXDX-105 and RXDX-106 [Member] | Daiichi Sankyo [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License agreement termination notice period										90 days
RXDX-108 [Member] | Daiichi Sankyo [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License expiration term										10 years
License Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Annual license payments	$ 2,000,000	$ 3,500,000	$ 7,000,000		$ 10,000,000		$ 2,000,000	$ 10,000,000	$ 3,500,000
Contingent milestone payments	38,000,000
Change in value of share issued	$ 13,400,000						13,400,000
Net proceeds from issuance of shares				$ 30,000,000
License Agreements [Member] | Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contingent milestone payments			$ 105,000,000
Royalties percentage			15.00%
License Agreements [Member] | Maximum [Member] | RXDX-105 [Member] | Daiichi Sankyo [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contingent milestone payments							44,500,000			$ 44,500,000
License Agreements [Member] | Maximum [Member] | RXDX-106 [Member] | Daiichi Sankyo [Member] | Upon Achievement of Development Regulatory and Sales Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contingent milestone payments							$ 47,500,000			47,500,000
License Agreements [Member] | Minimum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Royalties percentage			10.00%
License Agreements [Member] | Private Investment in Public Equity ( the "PIPE" Financing") [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Issuance of common stock	1,213,000						1,213,000
Net proceeds from issuance of shares										$ 30,000,000
License Agreements [Member] | Purchase Commitment [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Amount of service to be performed by NMS under the agreement			$ 1,000,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Oct. 31, 2015Building	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Loss Contingencies [Line Items]
Clinical expenses incurred to date		$ 15,000,000
Commercial Lease Agreement [Member]
Loss Contingencies [Line Items]
Number of buildings in commercial lease agreement | Building	2
Term of lease	10 years
Lease Description		The lease contains a one-time provision to terminate the lease for all or a portion of the facilities, effective as of the end of the 72nd month after the lease commencement date, subject to the payment of a termination fee defined in the lease agreement.
Research and Development Arrangement [Member]
Loss Contingencies [Line Items]
Clinical expenses total contracted cost		$ 68,900,000
Office Space [Member]
Loss Contingencies [Line Items]
Operating leases, rent expense		$ 636,000	$ 495,000	$ 208,000

Commitments and Contingencies43

Commitments and Contingencies - Non-cancellable Future Minimum Payments Under Capital and Operating Lease (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 194
2,017	167
2,018	0
2,019	0
2,020	0
Thereafter	0
Total minimum lease payments	361
Less amount representing interest	(16)
Present value of obligations under capital leases	345
Less current portion	(181)	$ (172)
Long-term capital lease obligations	164	$ 344
Present value of obligations under capital leases	345
2,016	1,541
2,017	2,852
2,018	4,482
2,019	4,500
2,020	4,635
Thereafter	8,435
Total minimum lease payments	$ 26,445

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	Mar. 17, 2015	Dec. 31, 2015	Nov. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Mar. 31, 2014	Nov. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Common stock, shares authorized		150,000,000						150,000,000	150,000,000
Preferred stock, shares authorized		10,000,000						10,000,000	10,000,000
Common Stock, voting right description								Common stock is entitled to one vote, and all shares rank equally as to voting and other matters.
Stock issued and sold							9,010,238
Net proceeds from issuance of shares							$ 51,000,000
Transaction costs							$ 3,000,000
Value of common stock repurchased									$ 1,000
Number of preferred shares converted to common stock										2,675,678
Restricted Stock [Member]
Class of Stock [Line Items]
Shares of common stock repurchased								0	400,000	0
Value of common stock repurchased									$ 1,440
Shares subject to future vesting		10,628						10,628
Common Stock Warrant [Member] | Maximum [Member]
Class of Stock [Line Items]
Warrant to purchase stock, shares		59,356						59,356
Warrant to purchase stock, exercise price per share		$ 8.78						$ 8.78
Warrants expiration date								2022-09
Common Stock Warrant [Member] | Minimum [Member]
Class of Stock [Line Items]
Warrant to purchase stock, exercise price per share		$ 3						$ 3
License Agreements [Member]
Class of Stock [Line Items]
Stock issued and sold			1,500,000
Net proceeds from issuance of shares			$ 30,000,000
Percentage of commission paid on gross proceeds of sales		3.00%
Number of shares reserved for issue under sales agreement		33,000,000						33,000,000
Cephalon Inc [Member]
Class of Stock [Line Items]
Stock issued and sold					4,158,750
Net proceeds from issuance of shares					$ 41,400,000
Transaction costs					$ 149,000
Common Stock [Member]
Class of Stock [Line Items]
Stock issued and sold				4,285,714		6,031,750		9,944,464	6,031,750	9,010,238
Net proceeds from issuance of shares				$ 70,100,000		$ 51,600,000
Transaction costs				$ 4,900,000		$ 3,600,000
Shares of common stock repurchased									400,000
Common Stock [Member] | Cephalon Inc [Member]
Class of Stock [Line Items]
Stock issued and sold	1,500,000

Equity Awards - Additional Info

Equity Awards - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jun. 11, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted during period, maximum contractual term	6 years 2 months 12 days	6 years	6 years 7 months 6 days
Estimated weighted-average fair value of stock options granted	$ 7.25	$ 4.72	$ 2.63
Unrecognized stock-based compensation expense related to unvested stock-based awards	$ 23
2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of Restricted Stock	90,000
2014 Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of restricted stock	5 years
2014 Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of restricted stock	4 years
Employee and Non-employee Stock Options [Member] | 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of equity awards				3,000,000
Employee and Non-employee Stock Options [Member] | 2011 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued for each share subject to a stock option granted	100.00%
Employee and Non-employee Stock Options [Member] | 2015 Inducement Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of equity awards				2,000,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense related to unvested stock-based awards, weighted average period of recognition	3 years 2 months 12 days
Stock Options [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expiration period from their date of grant	10 years
Stock Options [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total combined voting power	10.00%
Exercise price of option as a percentage of fair market value of common Stock on the grant date	100.00%
Stock Options [Member] | 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares that remained available for grant	1,674,558
Stock Options [Member] | Stock Option One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, term	5 years
Stock Options [Member] | Stock Option One [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of option as a percentage of fair market value of common Stock on the grant date	110.00%
Stock Options [Member] | 2014 Inducement Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional equity grants	0
Stock Options [Member] | 2015 Inducement Stock Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of option as a percentage of fair market value of common Stock on the grant date	100.00%
Non-Employee Stock Options [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted during period, maximum contractual term	10 years

Equity Awards - Summary of Equi

Equity Awards - Summary of Equity Incentive Plan Activity and Other Related Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Options Outstanding
Balance at beginning of period	2,991,655
Granted	2,695,991
Exercised	(77,477)
Forfeited	(359,229)
Balance at end of period	5,250,940	2,991,655
Exercisable at end of period	1,206,105
Weighted-Average Exercise Price
Balance at beginning of period	$ 6.67
Granted	11.63
Exercised	5.66
Forfeited	7.74
Balance at end of period	9.16	$ 6.67
Exercisable at end of period	$ 6.07
Weighted- Average Remaining Contractual Term
Balance at end of period	8 years 9 months 29 days	9 years 2 months 16 days
Exercisable at end of period	8 years 18 days
Aggregate Intrinsic Value
Balance at end of period	$ 24,565,711	$ 2,482,181
Exercisable at end of period	$ 8,837,446

Equity Awards - Assumptions Use

Equity Awards - Assumptions Used to Estimate Fair Value of Option Granted (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Volatility	69.00%	65.00%	59.00%
Expected life of option	6 years 2 months 12 days	6 years	6 years 7 months 6 days
Risk free interest rate	1.70%	1.80%	2.00%
Dividend yield	0.00%	0.00%	0.00%

Equity Awards - Summary of Stoc

Equity Awards - Summary of Stock-Based Compensation Expense for Equity Awards to Employees and Non-Employees (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense for employees and non-employees	$ 5,345	$ 2,283	$ 370
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense for employees and non-employees	2,576	896	240
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense for employees and non-employees	$ 2,769	$ 1,387	$ 130

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Statutory Federal Income Tax Provision to Actual Income Tax Provision (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Expected income tax benefit at federal statutory rate	$ (31,436)	$ (13,597)	$ (4,832)
State income tax benefit, net of federal benefit	(5,438)	(2,245)	(758)
Research credits	(1,854)	(1,118)	(204)
Intangible related to asset acquisition	(1,247)
Uncertain tax positions	1,386
Other	13	162	362
Change in valuation allowance	38,576	16,798	5,432
Income tax expense (benefit)	$ 0	$ 0	$ 0

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Tax [Line Items]
Non-current deferred tax asset	$ 62,600,000	$ 23,900,000
Unrecognized tax benefits	2,100,000	$ 0
Operating loss carryforward related to tax deductions	$ 1,000,000
Federal and state tax net operating loss carryforwards, beginning period of expiration	2,031
Operating loss and credit carryforwards limitation	Net operating loss and tax credit carryforwards in the event of a cumulative change in ownership in excess of 50% as defined in the Act.
Income tax interest or penalties recognized	$ 0
State and Local [Member]
Income Tax [Line Items]
Net operating losses	91,700,000
Tax credit carry forwards	$ 2,100,000
Federal [Member]
Income Tax [Line Items]
Net credit carryforwards, beginning period of expiration	2,031
Net operating losses	$ 92,300,000
Tax credit carry forwards	$ 1,800,000

Income Taxes - Summary of Unrec

Income Taxes - Summary of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance of unrecognized tax benefits	$ 0
Increase for prior year tax positions	2,100
Increase for current year tax positions	0	$ 0	$ 0
Ending balance of unrecognized tax benefits	$ 2,100	$ 0

Income Taxes - Summary of Signi

Income Taxes - Summary of Significant Components of Company's Defered Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Components of Deferred Tax Assets [Abstract]
Net operating loss carryforwards	$ 35,131	$ 13,091
Tax credit carryforwards	3,224	1,361
Stock-based compensation	2,848	848
Accrued compensation	1,485	62
Intangible assets recognized for tax purposes	13,143	7,566
In process research and development charge	5,865
Other, net	846	1,006
Total deferred tax assets	62,542	23,934
Deferred tax liabilities (depreciation)	(1,060)	(1,106)
Valuation allowance	(61,482)	(22,828)
Net deferred tax assets	$ 0	$ 0

Quarterly Data - Schedule of Qu

Quarterly Data - Schedule of Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Revenue							$ 150			$ 150
Research and development expenses	$ 34,068	$ 10,432	$ 8,796	$ 20,215	$ 16,124	$ 8,622	3,576	$ 2,183	$ 73,511	30,505	$ 10,171
Total operating expenses	40,658	14,289	12,651	22,982	19,606	10,845	5,615	3,945	90,580	40,011	13,904
Net loss	$ (41,210)	$ (14,621)	$ (13,120)	$ (23,507)	$ (19,757)	$ (10,703)	$ (5,423)	$ (4,107)	$ (92,458)	$ (39,990)	$ (14,214)
Net loss per share - basic and diluted	$ (1.32)	$ (0.49)	$ (0.51)	$ (1.15)	$ (1.01)	$ (0.55)	$ (0.28)	$ (0.28)	$ (3.44)	$ (2.18)	$ (3.83)

Quarterly Data - Schedule of 54

Quarterly Data - Schedule of Quarterly Financial Data (Parenthetical) (Detail) - USD ($) $ in Thousands	Nov. 06, 2015	Mar. 17, 2015	Aug. 04, 2014	Nov. 06, 2013	Dec. 31, 2014	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2015
Interim Reporting [Line Items]
In-process research and development charge associated with asset acquisition							$ 11,900			$ 11,880
License Agreements [Member]
Interim Reporting [Line Items]
Annual license payments	$ 2,000		$ 3,500	$ 7,000	$ 10,000	$ 2,000		$ 10,000	$ 3,500
Change in value of share issued	$ 13,400					$ 13,400
License Agreements [Member] | Private Investment in Public Equity ( the "PIPE" Financing") [Member]
Interim Reporting [Line Items]
Issuance of common stock	1,213,000					1,213,000
Cephalon Inc [Member] | Unregistered Common Stock [Member]
Interim Reporting [Line Items]
Stock issued for purchase of asset		1,500,000					1,500,000
Cephalon Inc [Member] | Drug Development Supplies [Member]
Interim Reporting [Line Items]
Payments to acquire drug development supplies							$ 900