Bellicum Pharmaceuticals (BLCM) 10-Q 9 Nov 16 2016 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	9 Months Ended
	Sep. 30, 2016	Oct. 28, 2016
Entity Information [Line Items]
Entity Registrant Name	Bellicum Pharmaceuticals, Inc.
Entity Central Index Key	1,358,403
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		27,105,698

Balance Sheets

Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 48,694	$ 70,241
Investment securities, available for sale - short-term	56,613	23,820
Accounts receivable, interest and other receivables	305	440
Prepaid expenses and other current assets	1,975	2,389
Total current assets	107,587	96,890
Investment securities, available for sale - long-term	23,791	56,304
Property and equipment, net	11,064	6,882
Other assets	262	330
TOTAL ASSETS	142,704	160,406
Current liabilities:
Accounts payable	1,618	2,106
Accrued expenses and other current liabilities	6,796	5,080
Current portion of capital lease obligation	19	13
Current portion of deferred rent	246	246
Total current liabilities	8,679	7,445
Commitments and contingencies: (Note: 10)
Long-term liabilities:
Long-term debt	20,076	0
Capital lease obligation	136	118
Deferred rent and other liabilities	726	826
TOTAL LIABILITIES	29,617	8,389
Stockholders’ equity:
Preferred stock: $0.01 par value; 10,000,000 shares authorized: no shares issued and outstanding	0	0
Common stock, $0.01 par value; 200,000,000 shares authorized at September 30, 2016 and December 31, 2015, 27,774,415 shares issued and 27,096,952 shares outstanding at September 30, 2016; 27,609,344 shares issued and 26,931,881 shares outstanding at December 31, 2015	278	276
Treasury stock: 677,463 shares held at September 30, 2016 and December 31, 2015	(5,056)	(5,056)
Additional paid-in capital	328,582	318,591
Accumulated other comprehensive income (loss)	78	(302)
Accumulated deficit	(210,795)	(161,492)
Total stockholders’ equity	113,087	152,017
Total liabilities and stockholders’ equity	$ 142,704	$ 160,406

Balance Sheets (Parenthetical)

Balance Sheets (Parenthetical) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Preferred Stock, Value, Issued	$ 0.01	$ 0.01
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 (usd per share)	$ 0.01	$ 0.01
Common stock, authorized (shares)	200,000,000	200,000,000
Common stock, issued (shares)	27,774,415	27,609,344
Common stock, outstanding (shares)	27,096,952	26,931,881
Treasury Stock, shares (shares)	677,463	677,463

Statements of Operations and Co

Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Grants	$ 114	$ 57	$ 307	$ 248
Total revenues	114	57	307	248
Operating Expenses [Abstract]
Research and development	13,290	9,792	36,459	23,522
General and administrative	4,252	3,882	12,715	8,856
Total operating expenses	17,542	13,674	49,174	32,378
Loss from operations	(17,428)	(13,617)	(48,867)	(32,130)
OTHER INCOME (EXPENSE):
Interest income	224	211	687	432
Interest expense	(515)	0	(1,123)	0
Loss on disposition of fixed assets			20	2
Other Expenses	0	(2)	0	(2)
Total other income (expense)	(291)	209	(436)	430
NET LOSS	$ (17,719)	$ (13,408)	$ (49,303)	$ (31,700)
Net loss per common share attributable to common shareholders, basic and diluted	$ (0.66)	$ (0.51)	$ (1.83)	$ (1.21)
Weighted-average shares outstanding, basic and diluted	26,966,630	26,376,456	26,919,984	26,301,914
Unrealized gain (loss) on investment securities	$ (18)	$ 0	$ 380	$ (204)
Comprehensive loss	$ (17,737)	$ (13,408)	$ (48,923)	$ (31,904)

Statements of Cash Flows

Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net loss	$ (49,303)	$ (31,700)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation	9,243	5,938
Depreciation expense	1,619	769
Amortization of premium on investment securities, net	449	377
Amortization of lease liability	(100)	(54)
Amortization of deferred financing costs	275	0
Loss on disposition of investment securities	0	14
Loss on disposition of fixed assets	20	2
Changes in operating assets and liabilities:
Receivables	135	(90)
Prepaid expenses and other assets	482	(681)
Accounts payable	(488)	325
Accrued liabilities and other	1,716	1,510
NET CASH USED IN OPERATING ACTIVITIES	(35,952)	(23,590)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of investment securities	(26,116)	(79,100)
Proceeds from sale of investment securities	25,767	7,743
Purchases of property and equipment	(5,787)	(4,597)
CASH USED IN INVESTING ACTIVITIES	(6,136)	(75,954)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from notes payable	20,000	0
Payment of debt issuance costs	(199)	0
Proceeds from exercise of stock options	562	0
Proceeds from issuance of common stock - ESPP	188	442
Payment of issuance costs on common stock	0	(8)
Payment on capital lease obligation	(10)	(5)
NET CASH PROVIDED BY FINANCING ACTIVITIES	20,541	429
NET CHANGE IN CASH AND CASH EQUIVALENTS	(21,547)	(99,115)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	70,241	191,602
CASH AND CASH EQUIVALENTS AT END OF PERIOD	48,694	92,487
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid	710	0
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Accrued issuance costs for long-term debt	1,390	0
Purchases of property and equipment in accounts payables and accrued liabilities	1,066	0
Capital lease obligation incurred for property and equipment	$ 34	$ 65

Organization and Business Descr

Organization and Business Description	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Business Description	ORGANIZATION AND BUSINESS DESCRIPTION Bellicum Pharmaceuticals, Inc., the Company or Bellicum, was incorporated in Delaware in July 2004 and is based in Houston, Texas. The Company is a clinical stage biopharmaceutical company focused on discovering and developing novel cellular immunotherapies for various forms of cancer, including both hematological cancers and solid tumors, as well as orphan inherited blood disorders. The Company is devoting substantially all of its present efforts to developing next-generation product candidates in some of the most important areas of cellular immunotherapy, including, hematopoietic stem cell transplantation, CAR T and TCR cell therapy. The Company has not generated any revenue from product sales to date and if the Company does not successfully commercialize any of the Company's product candidates, the Company will not be able to generate product revenue or achieve profitability. As of September 30, 2016, the Company had an accumulated deficit of $210.8 million . The Company is subject to risks common to companies in the biotechnology industry and the future success of the Company is dependent on its ability to successfully complete the development of, and obtain regulatory approval for, its product candidates, manage the growth of the organization, obtain additional financing necessary in order to develop, launch and commercialize its product candidates, and compete successfully with other companies in its industry.

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Significant Accounting Policies	SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying interim financial statements are unaudited. These unaudited interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and follow the requirements of the U.S. Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been omitted. In management’s opinion, the unaudited interim financial statements have been prepared on the same basis as the audited financial statements and include all adjustments necessary for the fair presentation of the Company’s financial position and its results of operations and its cash flows for the periods presented. All such adjustments are normal and recurring in nature. These statements do not include all disclosures required by GAAP and should be read in conjunction with the Company’s Annual Report on Form 10-K filed for the fiscal year ended December 31, 2015 (the Annual Report). A copy of the Annual Report is available on the SEC’s website, www.sec.gov , under the Company’s ticker symbol “BLCM” or on Bellicum’s website, www.bellicum.com . The results for the interim periods are not necessarily indicative of the results expected for the full fiscal year or any other interim period. Any reference in these footnotes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB). Use of Estimates The preparation of the financial statements in accordance with GAAP requires management to make certain estimates and judgments that affect the reported amounts of assets, liabilities, and expenses. Actual results could differ from those estimates. Net Loss and Net Loss per Share of Common Stock Attributable to Common Stockholders Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period without consideration for common stock equivalents. The following outstanding shares of common stock equivalents were excluded from the computations of diluted net loss per share of common stock attributable to common stockholders for the periods presented, as the effect of including such securities would be anti-dilutive. As of September 30, 2016 2015 Common Stock Equivalents: Number of shares Warrants to purchase common stock — 355,392 Unvested shares of restricted stock 88,236 117,647 Options to purchase common stock 4,501,561 3,547,949 4,589,797 4,020,988 Investment Securities Consistent with its investment policy, the Company invests its cash allocated to fund its short-term liquidity requirements with prominent financial institutions in bank depository accounts and institutional money market funds and the Company invests the remainder of its cash in corporate debt securities and municipal bonds rated at least A quality or equivalent, U.S. Treasury notes and bonds and U.S. and state government agency-backed securities. The Company determines the appropriate classification of investment securities at the time of purchase and reevaluates its classification as of each balance sheet date. All investment securities owned during the nine months ended September 30, were classified as available-for-sale. The cost of securities sold is based on the specific identification method. Investment securities are recorded as of each balance sheet date at fair value, with unrealized gains and, to the extent deemed temporary, unrealized losses included in stockholders’ equity. Interest and dividend income on investment securities, accretion of discounts and amortization of premiums and realized gains and losses are included in interest income in the Statements of Operations and Comprehensive Income (Loss). An investment security is considered to be impaired when a decline in fair value below its cost basis is determined to be other than temporary. The Company evaluates whether a decline in fair value of an investment security is below its cost basis and is other than temporary using available evidence. In the event that the cost basis of the investment security exceeds its fair value, the Company evaluates, among other factors, the amount and duration of the period that the fair value is less than the cost basis, the financial health of and business outlook for the issuer, including industry and sector performance, and operational and financing cash flow factors, overall market conditions and trends, the Company’s intent to sell the investment security and whether it is more likely than not that the Company would be required to sell the investment security before its anticipated recovery. If a decline in fair value is determined to be other than temporary, the Company records an impairment charge in the statement of comprehensive income (loss) and establishes a new cost basis in the investment. Property and Equipment Property and equipment consists of office furniture, laboratory equipment, computer equipment and software, equipment held under capital leases, and leasehold improvements. Property and equipment is depreciated using the straight-line method over the estimated useful lives of the respective assets. Office furniture 5 years Laboratory equipment 5 years Computer equipment and software 3 to 5 years Equipment under capital lease 5 years Leasehold improvements Shorter of asset’s useful life or remaining term of lease Rent The Company recognizes rent expense for leases with increasing annual rents on a straight-line basis over the term of the lease. The amount of rent expense in excess of cash payments is classified as accrued rent. Any lease incentives received are deferred and amortized over the term of the lease. Debt Issuance Costs Costs related to debt issuance are presented in the balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts. Application of New Accounting Standards Effective January 1, 2016, the Company adopted the accounting guidance in ASU No. 2015-03, “Simplifying the Presentation of Debt Issuance Costs,” which requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. See Note 5 to the unaudited financial statements included herein. New Accounting Requirements and Disclosures In February 2016, the FASB issued ASU No. 2016-02, “Leases,” which requires companies that lease assets to recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments, in its balance sheet. The pronouncement will also require additional disclosures about the amount, timing and uncertainty of cash flows arising from leases. This pronouncement is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018, and early adoption is permitted. The Company is currently evaluating the impact of adopting this standard on the Company’s financial statements. In March 2016, the FASB issued ASU No. 2016-09, “Compensation-Stock Compensation,” which simplifies accounting for share-based compensation arrangements, primarily as it relates to accounting for the income tax effects of share-based compensation. Under the pronouncement, an entity can make an entity-wide accounting policy decision to either estimate the number of awards that are expected to vest (current GAAP) or account for forfeitures as they occur. The pronouncement is effective for annual periods beginning after December 31, 2016, with earlier adoption permitted. The Company does not believe the adoption of this standard will have a material impact on the Company's financial statements. In June 2016, the FASB issued ASU 2016-13, “ Measurement of Credit Losses on Financial Instruments, ” which replaces the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to estimate credit losses. The new standard is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years with early adoption permitted in fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company does not believe the adoption of this standard will have a material impact on the Company's financial statements. In August 2016, the FASB issued ASU 2016-15, “ Classification of Certain Cash Receipts and Cash Payments, ” which provides guidance on the classification of certain cash receipts and payments in the statement of cash flows. The pronouncement is effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods. Earlier application is permitted in any interim or annual period. The Company does not believe the adoption of this standard will have a material impact on the Company's financial statements.

Fair Value Measurements and Inv

Fair Value Measurements and Investment Securities	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	FAI R VALU E MEASUREMENTS AND INVESTMENT SECURITIES Fair Value Measurement The Company follows ASC, Topic 820, Fair Value Measurements and Disclosures , or ASC 820, for application to financial assets. ASC 820 defines fair value, provides a consistent framework for measuring fair value under GAAP and requires fair value financial statement disclosures. ASC 820 applies only to the measurement and disclosure of financial assets that are required or permitted to be measured and reported at fair value under other ASC topics (except for standards that relate to share-based payments such as ASC Topic 718, Compensation – Stock Compensation ). The valuation techniques required by ASC 820 may be based on either observable or unobservable inputs. Observable inputs reflect readily obtainable data from independent sources, and unobservable inputs reflect the Company’s market assumptions. These inputs are classified into the following hierarchy: Level 1 Inputs – quoted prices (unadjusted) in active markets for identical assets that the reporting entity has the ability to access at the measurement date; Level 2 Inputs – inputs other than quoted prices included within Level 1 that are observable for the asset, either directly or indirectly; and Level 3 Inputs – unobservable inputs for the assets. The following tables present the Company’s investment securities (including, if applicable, those classified on the Company’s balance sheet as cash equivalents) that are measured at fair value on a recurring basis as of September 30, 2016 and December 31, 2015 , respectively: Fair Value Measurements at Reporting Date Balance at Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) (in thousands) Cash Equivalents: Money market funds $ 40,440 $ 40,440 $ — $ — Total Cash Equivalents $ 40,440 $ 40,440 $ — $ — Investment Securities: U.S. government agency-backed securities $ 30,781 $ — $ 30,781 $ — Corporate debt securities 46,624 — 46,624 — Municipal bonds 2,999 — 2,999 — Total Investment Securities $ 80,404 $ — $ 80,404 $ — Fair Value Measurements at Reporting Date Balance at Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) (in thousands) Cash Equivalents: Money market funds $ 52,714 $ 52,714 $ — $ — U.S. government agency-backed securities 9,500 — 9,500 — Total Cash Equivalents $ 62,214 $ 52,714 $ 9,500 $ — Investment Securities: U.S. government agency-backed securities $ 22,388 $ — $ 22,388 $ — Corporate debt securities 51,547 — 51,547 — Municipal bonds 6,189 — 6,189 — Total Investment Securities $ 80,124 $ — $ 80,124 $ — Corporate debt securities and municipal bonds are valued based on various observable inputs such as benchmark yields, reported trades, broker/dealer quotes, benchmark securities and bids. Investment securities, all classified as available-for-sale, consisted of the following as of September 30, 2016 : Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Aggregate Estimated Fair Value (in thousands) Investment Securities: U.S. government agency-backed securities $ 30,755 $ 27 $ (1 ) $ 30,781 Corporate debt securities 46,572 81 (29 ) 46,624 Municipal bonds 2,999 1 (1 ) 2,999 Total Investment Securities $ 80,326 $ 109 $ (31 ) $ 80,404 The Company's investment securities as of September 30, 2016 , will reach maturity between October 2016 and January 2019 , with a weighted-average maturity date in July 2017 . Management believes that the carrying value of the debt facility approximates its fair value, as the Company's debt facility bears interest at a rate that approximates prevailing market rates for instruments with similar characteristics. The fair value of the Company's debt facility is determined under Level 2 in the fair value hierarchy.

Accrued Expenses And Other Curr

Accrued Expenses And Other Current Liabilities	9 Months Ended
	Sep. 30, 2016
Accrued Expenses [Abstract]
Accrued Expenses And Other Current Liabilities	ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES Accrued expenses and other liabilities consist of the following: September 30, 2016 December 31, 2015 (in thousands) Accrued manufacturing costs $ 1,965 $ 2,412 Accrued payroll 1,338 1,332 Accrued property and equipment purchases 1,034 139 Accrued patient treatment costs 628 333 Accrued preclinical study costs 521 — Accrued medical facility fees 159 282 Accrued other 1,151 582 Total accrued expenses and other current liabilities $ 6,796 $ 5,080

Debt

Debt	9 Months Ended
	Sep. 30, 2016
Debt [Abstract]
Debt	DEBT Term Loan On March 10, 2016, (the Closing Date), the Company, entered into a Loan and Security Agreement (the Loan Agreement) with Hercules Capital, Inc. (Hercules), as agent and a lender, Hercules Technology II, L.P., as a lender and Hercules Technology III, L.P., as a lender, under which the Company borrowed $15.0 million on the Closing Date. On September 15, 2016, the Company, borrowed an additional $5.0 million under the Loan Agreement. Subject to the terms and conditions of the Loan Agreement, including approval by Hercules’ investment committee and the Company’s achievement of specified milestones in the Loan Agreement (the Milestones), the Company may borrow an additional $10.0 million through March 15, 2017. The Company intends to use the proceeds received under the Loan Agreement for funding the build-out of our manufacturing facilities and general corporate purposes. The interest rate will be calculated at a rate equal to the greater of either (i) 9.35% plus the prime rate as reported in The Wall Street Journal minus 3.50% , and (ii) 9.35% . Payments under the Loan Agreement are interest only for 18 months from the Closing Date, extendable to 24 months upon the Company achieving the Milestones. The interest only period will be followed by equal monthly payments of principal and interest amortized over a 30 months schedule through the maturity date of March 1, 2020 (the “Loan Maturity Date”); provided that if the Milestones are achieved, the Company will make equal monthly payments of principal and interest amortized over a 24 months schedule through the Loan Maturity Date. The remaining principal balance will be due and payable on the Loan Maturity Date. In addition, upon the Loan Maturity date or such earlier date specified in the Loan Agreement, a final payment equal to $1,390,000 (the Final Facility Charge), plus, subject to and contingent on the funding of the additional $10.0 million loan advance, an additional facility charge of $695,000 . The Company’s obligations under the Loan Agreement are secured by a security interest in substantially all of its assets, other than its intellectual property. If the Company prepays the loan, including interest, prior to December 31, 2016, there will be no prepayment penalty. If the Company prepays the loan, including interest, after January 1, 2017 but prior to the date that is 24 months following the Closing Date, it will pay Hercules a prepayment charge based on a prepayment fee equal to 2.00% of the amount prepaid; if the prepayment occurs thereafter, it will pay Hercules a prepayment charge based on a prepayment fee equal to 1.00% of the amount prepaid. The prepayment charge is also applicable upon the occurrence of a change of control of the Company. In addition to a prepayment charge, if any, the Company will pay Hercules the Final Facility Charge. The Loan Agreement includes customary affirmative and restrictive covenants, but does not include any financial maintenance covenants, and also includes standard events of default, including payment defaults. Upon the occurrence of an event of default, a default interest rate of an additional 5% may be applied to the outstanding loan balance and Hercules may declare all outstanding obligations immediately due and payable and take such other actions as set forth in the Loan Agreement. The Company paid expenses related to the Loan Agreement of $199,000 , which, alo ng with the Final Facility Charge of $1,390,000 , have been recorded as deferred financing costs, which offset long-term debt on the Company's balance sheet. Deferred financing costs of $1,589,000 will be amortized over the term of the loan, and will be included in interest expense. During the three and nine months ended September 30, 2016 , interest expense included $125,000 and $275,000 , respectively, of amortized deferred financing costs.

Leases

Leases	9 Months Ended
	Sep. 30, 2016
Leases [Abstract]
Leases	LEASES Leases On July 11, 2016, the Company entered into a First Amendment to Lease Agreement (the “Lease Amendment”) with Life Science Plaza Investment Group, LP, as successor-in-interest to Sheridan Hills Developments, L.P. (the “Original Landlord”) to amend the Lease Agreement, dated May 6, 2015, between the Company and the Original Landlord (the “Lease”). Pursuant to the Lease Amendment, the initial term of the Lease was extended to August 31, 2026 and the Company leased an aggregate of 3,328 additional square feet (the “Expansion Space”). For the Expansion Space, the Company is required to remit base monthly rent of approximately $5,800 , which will increase at an average approximate rate of 5% per year. On September 26, 2016, the Company entered into a Second Amendment to Lease Agreement (the “Second Amendment”) with Life Science Plaza Investment Group, LP. Pursuant to the Second Amendment, the Company leased an aggregate of 212 additional square feet of interior mechanical space on the 5th floor of the building, or the “Expansion Space”. For the Expansion Space, the Company is required to remit base monthly rent of approximately $385 , which will increase at an average approximate rate of 5% per year to August 31, 2026. Both lease amendments were evaluated for accounting treatment under ASC 840 - Leases , and determined to be operating leases.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation	SHARE-BASED COMPENSATION At September 30, 2016 , the Company had share-based awards outstanding under four share-based compensation plans as follows: The 2006 Stock Option Plan (the 2006 Plan) provided for the issuance of non-qualified stock options to employees, including officers, non-employee directors and consultants to the Company. As of September 30, 2016, 146,210 shares of common stock were reserved for issuance pursuant to outstanding options previously granted under the 2006 Plan to purchase common stock of the Company. The 2006 Plan was terminated by the Board in October 2014. The 2011 Stock Option Plan (the 2011 Plan) provided for the issuance of incentive and non-qualified stock options to employees, including officers, non-employee directors and consultants to the Company. As of September 30, 2016, 2,090,845 shares of common stock were reserved for issuance pursuant to outstanding options previously granted under the 2011 Plan to purchase common stock of the Company. The 2011 Plan terminated upon the effectiveness of the 2014 Plan described below. The 2014 Equity Incentive Plan (the 2014 Plan) became effective in December 2014, upon the closing of the Company's initial public offering. The 2014 Plan provides for the issuance of equity awards, including incentive and non-qualified stock options and restricted stock awards to employees, including officers, non-employee directors and consultants to the Company or its affiliates. The 2014 Plan also provides for the grant of performance cash awards and performance-based stock awards. The aggregate number of shares of common stock that are authorized for issuance under the 2014 Plan is 2,990,354 shares, plus any shares subject to outstanding options that were granted under the 2011 Plan or 2006 Plan that are forfeited, terminated, expired or are otherwise not issued. The 2014 Employee Stock Purchase Plan (the ESPP) provides for eligible Company employees, as defined by the ESPP, to be given an opportunity to purchase the Company's common stock at a discount, through payroll deductions, with stock purchases being made upon defined purchase dates. The ESPP authorizes the issuance of up to 550,000 shares of common stock, pursuant to purchase rights granted to the employees. No shares were purchased during the quarter ended September 30, 2016 or 2015. A summary of activity within the ESPP follows: Nine months ended September 30, 2016 2015 (amounts in thousands) Deductions from employees $ 290 $ 296 Share-based compensation expense recognized $ 208 $ 166 Remaining share-based compensation expense $ 58 $ 300 Proceeds received by the Company for ESPP $ 188 $ 159 Number of shares purchased by employees under ESPP 17,115 9,829 The Company granted options to purchase 46,000 and 1,086,457 shares of its common stock during the three and nine months ended September 30, 2016 , respectively. The fair value of the option grants during the nine months ended September 30, 2016 and 2015 was estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions: Black-Scholes option pricing weighted-average assumptions: Nine months ended September 30, 2016 2015 Expected volatility 71.9 % 87.3 % Expected term (in years) 6.08 6.08 Risk-free interest rate 1.78 % 1.70 % Expected dividend yield — % — % At September 30, 2016 , there was $29.3 million of unrecognized compensation expense related to unvested stock options and stock that is expected to be recognized over a weighted-average period of 2.6 years. During the three and nine months ended September 30, 2016 , the Company received cash proceeds from the exercise of stock options of approximately $0.3 million and $0.6 million , respectively. The aggregate intrinsic value of options exercised during the three and nine months ended September 30, 2016 was $0.8 million and $1.9 million , respectively. Share-based compensation for the three and nine months ended September 30, 2016 and 2015 are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 (in thousands) General and administrative $ 1,640 $ 1,336 $ 5,063 $ 3,412 Research and development 1,421 966 4,180 2,526 Total $ 3,061 $ 2,302 $ 9,243 $ 5,938 The following table summarizes the stock option activity for all stock plans during the nine months ended September 30: Options Weighted- (in years) Weighted- (in thousands) Aggregate Intrinsic Value (1) Outstanding at December 31, 2015 3,628,973 $ 10.32 8.03 $ 39,021 Granted 1,086,457 $ 17.40 Exercised (147,956 ) $ 3.79 Canceled or forfeited (65,913 ) $ 12.34 Outstanding at September 30, 2016 4,501,561 $ 12.22 7.79 $ 37,844 Exercisable at September 30, 2016 2,157,935 $ 7.62 6.71 $ 27,779 (1) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for the options that were in the money at September 30, 2016. At September 30, 2016 and December 31, 2015 , there were 88,236 shares of unvested common stock outstanding.

Grant Revenue

Grant Revenue	9 Months Ended
	Sep. 30, 2016
Grant Revenue [Abstract]
Grant Revenue	GRANT REVENUE NIH Grants During both 2015 and 2016, the Company was awarded $0.3 million under grants from the National Institutes of Health (NIH). The awards cover the period from April 2015 through March 2017. The awards were made pursuant to the authority of 42 USC 241 42 CFR 52, and are subject to the requirements of the statute. Funds spent under the grants are reimbursed through monthly reimbursement requests. Funds spent under the grants were approximately $0.1 million and $0.3 million during the three and nine months ended September 30, 2016 , respectively. As of September 30, 2016 and December 31, 2015, the Company had a receivable of $8,200 and $57,000 , respectively, pursuant to the grants.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Litigation The Company, from time to time, may be involved in litigation relating to claims arising out of its ordinary course of business. Management believes that there are no material claims or actions pending or threatened against the Company.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2016
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Collaboration Agreement - OPBG In October 2016, the Company and Ospedale Pediatrico Bambino Gesú (“OPBG”), entered into a collaboration agreement pursuant to which the Company and OPBG agreed to collaborate on research projects and early stage clinical trials for the design and development of various T cell immunotherapies. As consideration for OPBG’s performance of the research under the agreement and grant of certain licenses to the Company, the Company agreed to fund an aggregate of up to $4.4 million in project costs payable to OPBG or certain third party service providers, as applicable, over the term of the research, estimated to be four years. With respect to any inventions arising from the research, OPBG agreed to grant the Company an exclusive license to any such inventions, the terms of which will be set forth in a separate agreement. In addition, OPBG granted the Company paid-up, worldwide co-exclusive licenses for non-commercial development of OPBG’s CD19 and GD2 CAR-T technologies, as well as paid-up, worldwide exclusive licenses to commercialize its CD19 and GD2 CAR-T technologies, each to be governed by a separate agreement.

Significant Accounting Polici16

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying interim financial statements are unaudited. These unaudited interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and follow the requirements of the U.S. Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been omitted. In management’s opinion, the unaudited interim financial statements have been prepared on the same basis as the audited financial statements and include all adjustments necessary for the fair presentation of the Company’s financial position and its results of operations and its cash flows for the periods presented. All such adjustments are normal and recurring in nature. These statements do not include all disclosures required by GAAP and should be read in conjunction with the Company’s Annual Report on Form 10-K filed for the fiscal year ended December 31, 2015 (the Annual Report). A copy of the Annual Report is available on the SEC’s website, www.sec.gov , under the Company’s ticker symbol “BLCM” or on Bellicum’s website, www.bellicum.com . The results for the interim periods are not necessarily indicative of the results expected for the full fiscal year or any other interim period. Any reference in these footnotes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB).
Use of Estimates	Use of Estimates The preparation of the financial statements in accordance with GAAP requires management to make certain estimates and judgments that affect the reported amounts of assets, liabilities, and expenses. Actual results could differ from those estimates.
Net Loss and Net Loss per Share of Common Stock Attributable to Common Stockholders	Net Loss and Net Loss per Share of Common Stock Attributable to Common Stockholders Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period without consideration for common stock equivalents.
Investment Securities	Investment Securities Consistent with its investment policy, the Company invests its cash allocated to fund its short-term liquidity requirements with prominent financial institutions in bank depository accounts and institutional money market funds and the Company invests the remainder of its cash in corporate debt securities and municipal bonds rated at least A quality or equivalent, U.S. Treasury notes and bonds and U.S. and state government agency-backed securities. The Company determines the appropriate classification of investment securities at the time of purchase and reevaluates its classification as of each balance sheet date. All investment securities owned during the nine months ended September 30, were classified as available-for-sale. The cost of securities sold is based on the specific identification method. Investment securities are recorded as of each balance sheet date at fair value, with unrealized gains and, to the extent deemed temporary, unrealized losses included in stockholders’ equity. Interest and dividend income on investment securities, accretion of discounts and amortization of premiums and realized gains and losses are included in interest income in the Statements of Operations and Comprehensive Income (Loss). An investment security is considered to be impaired when a decline in fair value below its cost basis is determined to be other than temporary. The Company evaluates whether a decline in fair value of an investment security is below its cost basis and is other than temporary using available evidence. In the event that the cost basis of the investment security exceeds its fair value, the Company evaluates, among other factors, the amount and duration of the period that the fair value is less than the cost basis, the financial health of and business outlook for the issuer, including industry and sector performance, and operational and financing cash flow factors, overall market conditions and trends, the Company’s intent to sell the investment security and whether it is more likely than not that the Company would be required to sell the investment security before its anticipated recovery. If a decline in fair value is determined to be other than temporary, the Company records an impairment charge in the statement of comprehensive income (loss) and establishes a new cost basis in the investment.
Property and Equipment	Property and Equipment Property and equipment consists of office furniture, laboratory equipment, computer equipment and software, equipment held under capital leases, and leasehold improvements. Property and equipment is depreciated using the straight-line method over the estimated useful lives of the respective assets.
Build-to-Suit Lease Accounting	Rent The Company recognizes rent expense for leases with increasing annual rents on a straight-line basis over the term of the lease. The amount of rent expense in excess of cash payments is classified as accrued rent. Any lease incentives received are deferred and amortized over the term of the lease.
Debt Issuance Costs	Debt Issuance Costs Costs related to debt issuance are presented in the balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts.
New Accounting Requirements and Disclosures	Application of New Accounting Standards Effective January 1, 2016, the Company adopted the accounting guidance in ASU No. 2015-03, “Simplifying the Presentation of Debt Issuance Costs,” which requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. See Note 5 to the unaudited financial statements included herein. New Accounting Requirements and Disclosures In February 2016, the FASB issued ASU No. 2016-02, “Leases,” which requires companies that lease assets to recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments, in its balance sheet. The pronouncement will also require additional disclosures about the amount, timing and uncertainty of cash flows arising from leases. This pronouncement is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018, and early adoption is permitted. The Company is currently evaluating the impact of adopting this standard on the Company’s financial statements. In March 2016, the FASB issued ASU No. 2016-09, “Compensation-Stock Compensation,” which simplifies accounting for share-based compensation arrangements, primarily as it relates to accounting for the income tax effects of share-based compensation. Under the pronouncement, an entity can make an entity-wide accounting policy decision to either estimate the number of awards that are expected to vest (current GAAP) or account for forfeitures as they occur. The pronouncement is effective for annual periods beginning after December 31, 2016, with earlier adoption permitted. The Company does not believe the adoption of this standard will have a material impact on the Company's financial statements. In June 2016, the FASB issued ASU 2016-13, “ Measurement of Credit Losses on Financial Instruments, ” which replaces the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to estimate credit losses. The new standard is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years with early adoption permitted in fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company does not believe the adoption of this standard will have a material impact on the Company's financial statements. In August 2016, the FASB issued ASU 2016-15, “ Classification of Certain Cash Receipts and Cash Payments, ” which provides guidance on the classification of certain cash receipts and payments in the statement of cash flows. The pronouncement is effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods. Earlier application is permitted in any interim or annual period. The Company does not believe the adoption of this standard will have a material impact on the Company's financial statements.

Significant Accounting Polici17

Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Earnings Per Share, Potentially Dilutive Securities	The following outstanding shares of common stock equivalents were excluded from the computations of diluted net loss per share of common stock attributable to common stockholders for the periods presented, as the effect of including such securities would be anti-dilutive. As of September 30, 2016 2015 Common Stock Equivalents: Number of shares Warrants to purchase common stock — 355,392 Unvested shares of restricted stock 88,236 117,647 Options to purchase common stock 4,501,561 3,547,949 4,589,797 4,020,988
Property and Equipment	Office furniture 5 years Laboratory equipment 5 years Computer equipment and software 3 to 5 years Equipment under capital lease 5 years Leasehold improvements Shorter of asset’s useful life or remaining term of lease

Fair Value Measurements and I18

Fair Value Measurements and Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring Basis	The following tables present the Company’s investment securities (including, if applicable, those classified on the Company’s balance sheet as cash equivalents) that are measured at fair value on a recurring basis as of September 30, 2016 and December 31, 2015 , respectively: Fair Value Measurements at Reporting Date Balance at Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) (in thousands) Cash Equivalents: Money market funds $ 40,440 $ 40,440 $ — $ — Total Cash Equivalents $ 40,440 $ 40,440 $ — $ — Investment Securities: U.S. government agency-backed securities $ 30,781 $ — $ 30,781 $ — Corporate debt securities 46,624 — 46,624 — Municipal bonds 2,999 — 2,999 — Total Investment Securities $ 80,404 $ — $ 80,404 $ — Fair Value Measurements at Reporting Date Balance at Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) (in thousands) Cash Equivalents: Money market funds $ 52,714 $ 52,714 $ — $ — U.S. government agency-backed securities 9,500 — 9,500 — Total Cash Equivalents $ 62,214 $ 52,714 $ 9,500 $ — Investment Securities: U.S. government agency-backed securities $ 22,388 $ — $ 22,388 $ — Corporate debt securities 51,547 — 51,547 — Municipal bonds 6,189 — 6,189 — Total Investment Securities $ 80,124 $ — $ 80,124 $ —
Available-for-sale Securities	Investment securities, all classified as available-for-sale, consisted of the following as of September 30, 2016 : Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Aggregate Estimated Fair Value (in thousands) Investment Securities: U.S. government agency-backed securities $ 30,755 $ 27 $ (1 ) $ 30,781 Corporate debt securities 46,572 81 (29 ) 46,624 Municipal bonds 2,999 1 (1 ) 2,999 Total Investment Securities $ 80,326 $ 109 $ (31 ) $ 80,404

Accrued Expenses And Other Cu19

Accrued Expenses And Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2016
Accrued Expenses [Abstract]
Schedule of Accrued Liabilities	Accrued expenses and other liabilities consist of the following: September 30, 2016 December 31, 2015 (in thousands) Accrued manufacturing costs $ 1,965 $ 2,412 Accrued payroll 1,338 1,332 Accrued property and equipment purchases 1,034 139 Accrued patient treatment costs 628 333 Accrued preclinical study costs 521 — Accrued medical facility fees 159 282 Accrued other 1,151 582 Total accrued expenses and other current liabilities $ 6,796 $ 5,080

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity [Table Text Block]	A summary of activity within the ESPP follows: Nine months ended September 30, 2016 2015 (amounts in thousands) Deductions from employees $ 290 $ 296 Share-based compensation expense recognized $ 208 $ 166 Remaining share-based compensation expense $ 58 $ 300 Proceeds received by the Company for ESPP $ 188 $ 159 Number of shares purchased by employees under ESPP 17,115 9,829
Valuation Assumptions	The fair value of the option grants during the nine months ended September 30, 2016 and 2015 was estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions: Black-Scholes option pricing weighted-average assumptions: Nine months ended September 30, 2016 2015 Expected volatility 71.9 % 87.3 % Expected term (in years) 6.08 6.08 Risk-free interest rate 1.78 % 1.70 % Expected dividend yield — % — %
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]	Share-based compensation for the three and nine months ended September 30, 2016 and 2015 are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 (in thousands) General and administrative $ 1,640 $ 1,336 $ 5,063 $ 3,412 Research and development 1,421 966 4,180 2,526 Total $ 3,061 $ 2,302 $ 9,243 $ 5,938
Schedule of Share-based Compensation, Stock Options, Activity	The following table summarizes the stock option activity for all stock plans during the nine months ended September 30: Options Weighted- (in years) Weighted- (in thousands) Aggregate Intrinsic Value (1) Outstanding at December 31, 2015 3,628,973 $ 10.32 8.03 $ 39,021 Granted 1,086,457 $ 17.40 Exercised (147,956 ) $ 3.79 Canceled or forfeited (65,913 ) $ 12.34 Outstanding at September 30, 2016 4,501,561 $ 12.22 7.79 $ 37,844 Exercisable at September 30, 2016 2,157,935 $ 7.62 6.71 $ 27,779 (1) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for the options that were in the money at September 30, 2016.

Organization and Business Des21

Organization and Business Description (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ (210,795)	$ (161,492)

Significant Accounting Polici22

Significant Accounting Policies - Common Stock Equivalents (Details) - shares	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	4,589,797	4,020,988
Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	88,236	117,647
Equity Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	4,501,561	3,547,949
Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	355,392

Significant Accounting Polici23

Significant Accounting Policies - Property and Equipment (Details)	9 Months Ended
	Sep. 30, 2016
Office furniture
Property, Plant and Equipment [Line Items]
Property and Equipment, useful life	5 years
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, useful life	5 years
Equipment under capital lease
Property, Plant and Equipment [Line Items]
Property and Equipment, useful life	5 years
Computer equipment | Minimum
Property, Plant and Equipment [Line Items]
Property and Equipment, useful life	3 years
Computer equipment | Maximum
Property, Plant and Equipment [Line Items]
Property and Equipment, useful life	5 years
Software | Minimum
Property, Plant and Equipment [Line Items]
Property and Equipment, useful life	3 years
Software | Maximum
Property, Plant and Equipment [Line Items]
Property and Equipment, useful life	5 years

Fair Value Measurements and I24

Fair Value Measurements and Investment Securities (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	$ 80,404,000
Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	40,440,000	$ 62,214,000
Total Investment Securities	80,404,000	80,124,000
Fair Value, Measurements, Recurring | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	30,781,000
Fair Value, Measurements, Recurring | Corporate debt securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	46,624,000
Fair Value, Measurements, Recurring | Municipal bonds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	2,999,000
Fair Value, Measurements, Recurring | Money market funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	40,440,000	52,714,000
Fair Value, Measurements, Recurring | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents		9,500,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	40,440,000	52,714,000
Total Investment Securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Corporate debt securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Municipal bonds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Money market funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	40,440,000	52,714,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	0	9,500,000
Total Investment Securities	80,404,000	80,124,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	30,781,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Corporate debt securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	46,624,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Municipal bonds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	2,999,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Money market funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents		9,500,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	0	0
Total Investment Securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Corporate debt securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Municipal bonds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Money market funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Cash Equivalents		0
U.S. government agency-backed securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	30,781,000
U.S. government agency-backed securities | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		22,388,000
U.S. government agency-backed securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		0
U.S. government agency-backed securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		22,388,000
U.S. government agency-backed securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		0
Corporate debt securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	46,624,000
Corporate debt securities | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		51,547,000
Corporate debt securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		0
Corporate debt securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		51,547,000
Corporate debt securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		0
Municipal bonds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities	$ 2,999,000
Municipal bonds | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		6,189,000
Municipal bonds | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		0
Municipal bonds | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		6,189,000
Municipal bonds | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Investment Securities		$ 0

Fair Value Measurements and I25

Fair Value Measurements and Investment Securities - Fair Value (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 80,326,000
Gross Unrealized Gains	109,000
Gross Unrealized Losses	(31,000)
Aggregate Estimated Fair Value	80,404,000
U.S. government agency-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	30,755,000
Gross Unrealized Gains	27,000
Gross Unrealized Losses	(1,000)
Aggregate Estimated Fair Value	30,781,000
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	46,572,000
Gross Unrealized Gains	81,000
Gross Unrealized Losses	(29,000)
Aggregate Estimated Fair Value	46,624,000
Municipal bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,999,000
Gross Unrealized Gains	1,000
Gross Unrealized Losses	(1,000)
Aggregate Estimated Fair Value	2,999,000
Fair Value, Measurements, Recurring
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value	80,404,000	$ 80,124,000
Total Cash Equivalents	40,440,000	62,214,000
Fair Value, Measurements, Recurring | U.S. government agency-backed securities
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value		22,388,000
Fair Value, Measurements, Recurring | Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value		51,547,000
Fair Value, Measurements, Recurring | Municipal bonds
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value		6,189,000
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value	0	0
Total Cash Equivalents	$ 40,440,000	52,714,000
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | U.S. government agency-backed securities
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value		0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value		0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Municipal bonds
Schedule of Available-for-sale Securities [Line Items]
Aggregate Estimated Fair Value		$ 0

Accrued Expenses And Other Cu26

Accrued Expenses And Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accrued Expenses [Abstract]
Accrued manufacturing costs	$ 1,965	$ 2,412
Accrued payroll	1,338	1,332
Accrued property and equipment purchases	1,034	139
Accrued patient treatment costs	628	333
Accrued preclinical study costs	521	0
Accrued medical facility fees	159	282
Accrued other	1,151	582
Total accrued expenses and other current liabilities	$ 6,796	$ 5,080

Debt (Details)

Debt (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 15, 2016	Mar. 10, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
Long-term debt	$ 20,076,000	$ 20,076,000		$ 5,000,000	$ 15,000,000	$ 0
Contingent additional borrowing capacity	$ 10,000,000	$ 10,000,000			$ 10,000,000
Percentage bearing fixed interest, percentage rate	9.35%	9.35%
Payment terms, interest only payments, period 1		18 months
Payment terms, interest only payments, period 2		24 months
Payment terms, principal and interest payments, period 1		30 months
Payment terms, principal and interest payments, period 2		24 months
Periodic payment, final payment amount	$ 1,390,000	$ 1,390,000
Periodic payment, final payment amount, additional amount, scenario 2	$ 695,000	$ 695,000
Period threshold for prepayment penalty percentage evaluation		24 months
Early repayment fee, percentage of prepaid amount, period 1	2.00%	2.00%
Early repayment fee, percentage of prepaid amount, period 2	1.00%	1.00%
Debt default, additional interest rate on outstanding balance	5.00%	5.00%
Payments of debt issuance costs		$ 199,000	$ 0
Deferred finance costs, noncurrent, net	$ 1,390,000	1,390,000
Deferred finance costs, gross	1,589,000	1,589,000
Amortization of financing costs and discounts	$ 125,000	$ 275,000
Prime Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate		3.50%

Leases (Details)

Leases (Details)	Sep. 26, 2016USD ($)ft²	Jul. 11, 2016USD ($)ft²
First Amendment to Lease Agreement
Operating Leased Assets [Line Items]
Area of real estate property | ft²		3,328
Rent expense | $		$ 5,800
Increase in rent, percent		5.00%
Second Amendment to Lease Agreement
Operating Leased Assets [Line Items]
Area of real estate property | ft²	212
Rent expense | $	$ 385
Increase in rent, percent	5.00%

Share-Based Compensation - Narr

Share-Based Compensation - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016USD ($)shares	Sep. 30, 2015shares	Sep. 30, 2016USD ($)planshares	Sep. 30, 2015shares	Dec. 31, 2015shares	Dec. 31, 2014shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-based compensation plans | plan			4
Granted (shares)	46,000		1,086,457
Compensation cost not yet recognized | $	$ 29.3		$ 29.3
Period for recognition			2 years 7 months
Cash received from exercise of stock options | $	0.3		$ 0.6
Intrinsic value of options, exercises in period | $	$ 0.8		$ 1.9
Equity instruments other than options, nonvested	88,236		88,236		88,236
2006 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	146,210		146,210
2011 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	2,090,845		2,090,845
2014 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	2,990,354		2,990,354
2014 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant						550,000
Stock issued during period, shares, employee stock purchase plans	0	0	17,115	9,829

Share-Based Compensation - Empl

Share-Based Compensation - Employee Stock Purchase Plan (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation			$ 9,243	$ 5,938
2014 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deductions from employees			290	296
Share-based compensation expense recognized			208	166
Share-based compensation			58	300
Proceeds received by the Company for ESPP			$ 188	$ 159
Number of shares purchased by employees under ESPP	0	0	17,115	9,829

Share-Based Compensation - Valu

Share-Based Compensation - Valuation Assumptions (Details)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected volatility	71.90%	87.30%
Expected term (in years)	6 years 29 days	6 years 29 days
Risk-free interest rate	1.78%	1.70%
Expected dividend yield	0.00%	0.00%

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of Compensation Cost for Share-Based Payment Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 3,061	$ 2,302	$ 9,243	$ 5,938
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	1,640	1,336	5,063	3,412
Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 1,421	$ 966	$ 4,180	$ 2,526

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2016	Dec. 31, 2015
Options
December 31, 2015 (shares)		3,628,973
Granted (shares)	46,000	1,086,457
Exercised (shares)		(147,956)
Canceled or forfeited (shares)		(65,913)
Outstanding at September 30, 2016 (shares)	4,501,561	4,501,561	3,628,973
Exercisable at September 30, 2016 (shares)	2,157,935	2,157,935
Weighted- Average Exercise Price Per Share
December 31, 2015 (usd per share)		$ 10.32
Granted (usd per share)		17.40
Exercised (usd per share)		3.79
Canceled or forfeited (usd per share)		12.34
Outstanding at September 30, 2016 (usd per share)	$ 12.22	12.22	$ 10.32
Exercisable at September 30, 2016 (usd per share)	$ 7.62	$ 7.62
Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Term, Outstanding		7 years 9 months 14 days	8 years 12 days
Weighted Average Remaining Contractual Term, Exercisable		6 years 8 months 16 days
Aggregate Intrinsic Value, Outstanding	$ 37,844	$ 37,844	$ 39,021
Aggregate Intrinsic Value, Exercisable	$ 27,779	$ 27,779

Grant Revenue (Details)

Grant Revenue (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenue from grants	$ 114,000	$ 57,000	$ 307,000	$ 248,000
National Institutes of Health Grant
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenue from grants			300,000
Costs and expenses	100,000		300,000
Grants receivable	$ 8,200		$ 8,200		$ 57,000

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event $ in Millions	1 Months Ended
	Oct. 31, 2016USD ($)
Subsequent Event [Line Items]
Long-term purchase commitment, amount	$ 4.4
Research and Development Arrangement [Member]
Subsequent Event [Line Items]
Research term (in years)	4 years