Document and Entity Information Document	3 Months Ended
Document and Entity Information Document	Mar. 31, 2015	Apr. 30, 2015
Entity Information [Line Items]
Entity Registrant Name	Bellicum Pharmaceuticals, Inc.
Entity Central Index Key	0001358403
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		26,378,474

Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 183,638	$ 191,602
Accounts receivable	94	298
Prepaid expenses and other current assets	1,279	1,322
Total current assets	185,011	193,222
Property and equipment, net of accumulated depreciation	3,164	2,427
Other assets	97	145
ASSETS	188,272	195,794
Current liabilities:
Accounts payable	1,115	1,209
Accrued expenses	1,079	2,163
Deferred revenue	0	13
Current portion of deferred rent	26	97
Current portion of deferred manufacturing costs	428	154
Total current liabilities	2,648	3,636
Long-term liabilities:
Deferred rent	263	209
Deferred Manufacturing Costs	0	313
Total long-term liabilities	263	522
TOTAL LIABILITIES	2,911	4,158
Commitments and Contingencies
Stockholders’ equity:
Common stock, $0.01 par value; 200,000,000 shares authorized at March 31, 2015 and December 31, 2014; 27,055,937 shares issued and 26,378,474 shares issued and outstanding; at March 31, 2015; 27,050,055 issued and 26,372,592 issued and outstanding at December 31, 2014	271	271
Treasury stock: 677,463 shares held at March 31, 2015 and December 31, 2014	(5,056)	(5,056)
Additional paid-in capital	310,848	309,365
Accumulated deficit	(120,702)	(112,944)
Total stockholders’ equity	185,361	191,636
LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 188,272	$ 195,794

Balance Sheets Balance Sheet Parenthetical (USD $)	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
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)	27,055,937	27,050,055
Common stock, outstanding (shares)	26,378,474	26,372,592
Treasury Stock, shares (shares)	677,463	677,463

Statements of Operations (USD $)	3 Months Ended
Statements of Operations (USD $)	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Grants	$ 107,000	$ 552,000
Total revenues	107,000	552,000
OPERATING EXPENSES	7,915,000	2,829,000
Research and development	5,718,000	2,389,000
General and administrative	2,197,000	440,000
Loss from operations	(7,808,000)	(2,277,000)
Interest income	50,000	3,000
Interest expense	0	(16,000)
Total other income (expense)	50,000	(13,000)
NET LOSS	(7,758,000)	(2,290,000)
Preferred stock dividends	0	(540,000)
Net loss attributable to common shareholders, basic and diluted	$ (7,758,000)	$ (2,830,000)
Net loss per common share attributable to common shareholders, basic and diluted	$ (0.30)	$ (1.52)
Weighted-average shares outstanding, basic and diluted	26,259,392	1,863,350

Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Net loss	$ (7,758)	$ (2,290)
Depreciation expense	196	159
Share-based compensation	1,489	76
Amortization of lease liability	(17)	(28)
Accounts receivable	204	(527)
Prepaid expenses and other current assets	91	17
Accounts payable	(94)	(106)
Accrued liabilities	(1,176)	(581)
Deferred costs	(52)	62
Other liabilities	92	0
NET CASH USED IN OPERATING ACTIVITIES	(7,025)	(3,218)
Purchases of property and equipment	(933)	(22)
CASH USED IN INVESTING ACTIVITIES	(933)	(22)
Proceeds from exercise of stock options	2	0
Proceeds from issuance of Series B preferred stock	0	7,320
Payment of issuance costs of common stock	(8)	0
Proceeds from exercise of common warrants	0	201
Payments on line of credit	0	(100)
NET CASH PROVIDED (USED) BY FINANCING ACTIVITIES	(6)	7,421
NET CHANGE IN CASH AND CASH EQUIVALENTS	(7,964)	4,181
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	183,638	15,349
Dividends accrued on preferred stock	$ 0	$ 540

Organization and Business Description (Notes)	3 Months Ended
Organization and Business Description (Notes)	Mar. 31, 2015
Organization and Business Description [Abstract]
Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]	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 cell therapy and dendritic cell vaccines. The Company has not generated any revenue from product sales to date and does not anticipate generating revenues from product sales in the foreseeable future. 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, managing the growth of the organization, obtaining additional financing necessary in order launch and commercialize its product candidates, and competing successfully with other companies in its industry.

Significant Accounting Policies (Notes)

3 Months Ended

Mar. 31, 2015

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 following 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, which include only normal recurring 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. 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, 2014 (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.

Historically, prior to the Company’s initial public offering of its common stock, or IPO, in December 2014, the fair values of the shares of common stock underlying the Company’s share-based awards were estimated on each grant date by its Board of Directors. Given the absence of a public trading market for the Company’s common stock, its Board of Directors exercised reasonable judgment and considered a number of objective and subjective factors to determine the best estimate of the fair value of its common stock, including the following:


•	its stage of development;


•	its operational and financial performance;


•	the nature of its services and its competitive position in the marketplace;


•	the value of companies that it considers peers based on a number of factors, including similarity to the Company with respect to industry and business model;


•	the likelihood of achieving a liquidity event, such as an initial public offering and the nature and history of its business;


•	issuances of preferred stock and the rights, preferences, and privileges of its preferred stock relative to those of its common stock;


•	business conditions and projections;


•	the history of the Company and progress of its research and development efforts and clinical trials; and


•	the lack of marketability of its common stock.

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 share of common stock outstanding during the period without consideration for common stock equivalents. Diluted net loss per share of common stock is the same as basic net loss per share of common stock, since the effects of potentially dilutive securities are antidilutive. The net loss per share of common stock attributable to common stockholders is computed using the two-class method required for participating securities. All series of the Company’s convertible preferred stock were considered to be participating securities as they were entitled to participate in undistributed earnings with shares of common stock. Due to the Company’s net loss, there is no impact on the earnings per share calculation in applying the two-class method since the participating securities have no legal requirement to share in any losses.

The following outstanding shares of common stock equivalents were excluded from the computations of diluted net loss per shares of common stock attributable to common stockholders for the periods presented as the effect of including such securities would be anti-dilutive.



Common Stock Equivalents:	March 31, 2015	March 31, 2014
Series A Preferred Stock Convertible Preferred Stock - as converted to common stock	—	1,496,782
Series B Preferred Stock Convertible Preferred Stock - as converted to common stock	—	4,791,740
Warrants to purchase common stock	355,392	473,031
Options to purchase common stock	3,443,011	1,584,692
	3,798,403	8,346,245

- Definition

The entire disclosure for all significant accounting policies of the reporting entity.

+ References+ Details

Fair Value of Financial Instruments (Notes)

3 Months Ended

Mar. 31, 2015

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

FAIR VALUE OF FINANCIAL INSTRUMENTS

ASC 820, Fair Value Measurement, provides a comprehensive framework for measuring the fair value of assets and liabilities, which provides for consistency in how fair value determinations are made under various existing accounting standards that permit, or in some cases require, estimates of fair market value.

Financial assets and liabilities that have recurring fair value measurements are shown below (in thousands):



	Balance at March 31, 2015		Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets:
Money market funds	$	181,636	$	181,636	$	—	$	—
Total	$	181,636	$	181,636	$	—	$	—



	Balance at December 31, 2014		Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets:
Money market funds	$	43,587	$	43,587	$	—	$	—
Total	$	43,587	$	43,587	$	—	$	—

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References+ Details

Accrued Expenses (Notes)

3 Months Ended

Mar. 31, 2015

Accrued Expenses [Abstract]

Accrued Expenses

ACCRUED EXPENSES

Accrued liabilities consist of the following (in thousands):



	March 31, 2015		December 31, 2014
Accrued payroll	$	—	$	731
Commission on exercise of warrants	—		731
Medical facility fees	559		201
Patient treatment costs	125		128
License costs	52		50
Other	343		322
Total accrued expenses	$	1,079	$	2,163

Stockholders' Equity (Notes)	3 Months Ended
Stockholders' Equity (Notes)	Mar. 31, 2015
Stockholders' Equity Attributable to Parent [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	STOCKHOLDERS' EQUITY Preferred Stock As of March 31, 2015 and December 31, 2014, the Company had 10,000,000 authorized shares of preferred stock, with none outstanding and a par value of $0.01 per share. Common Stock As of March 31, 2015 and December 31, 2014, the Company had 200,000,000 authorized shares of common stock with a par value of $0.01 per share. Exercise of Common Warrants In March 2014, the Company issued 393,523 shares of common stock for $200,700, or $0.51 per share in conjunction with the exercise of warrants expiring in March of 2014. Reverse Stock Split On December 4, 2014, the Company’s board of directors and stockholders approved an amendment to the Company’s amended and restated certificate of incorporation to effect a reverse split of shares of the Company’s common stock on a 1-for-1.7 basis (the Reverse Stock Split). The par value and the authorized shares of the common stock were not adjusted as a result of the Reverse Stock Split. All issued and outstanding common stock, options for common stock, warrants for common stock, and per share amounts contained in the financial statements have been retroactively adjusted to reflect this Reverse Stock Split for all periods presented.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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+ Details

Share-Based Compensation

3 Months Ended

Mar. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share-based Compensation

SHARE-BASED COMPENSATION

At March 31, 2015, the Company had share-based awards 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 March 31, 2015, 161,174 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 March 31, 2015, 2,425,561 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 our 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 (ESPP) provides for eligible Company employees, as defined by the ESPP, to be given an opportunity to purchase our 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 our Common Stock, pursuant to purchase rights granted to our employees. The ESPP was approved by the Board and our stockholders in December 2014 and employee payroll deductions of approximately $101,000 were withheld during the first quarter of 2015. During the three months ended March 31, 2015, no stock purchases were made under the ESPP and therefore there was no share-based compensation cost. The Company expects to record share-based compensation expense in the future to the extent that shares are purchased for less than fair market value under the ESPP.

Share-based compensation expense is included within operating expenses as follows (in thousands):



	Three Months Ended March 31,
	2015		2014
Research and development	$	599	$	66
General and administrative	890		10
Total share-based compensation	$	1,489	$	76

The Company granted options to purchase 10,293 shares of its common stock during the three months ended March 31, 2014. The fair value of the option grants during the three months ended March 31, 2015 and 2014 was estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:



	Three Months Ended March 31,
	2015		2014
Expected volatility	91.2	%	101.0	%
Expected term (in years)	6.08		6.25
Risk-free interest rate	1.6	%	2.7	%
Expected dividend yield	—	%	—	%

At March 31, 2015, there was $28.9 million of unrecognized compensation expense related to unvested stock options and stock that is expected to be recognized over a weighted-average period of 3.7 years.

During the three months ended March 31, 2015, the company received cash proceeds from the exercise of stock options of approximately $2,000. The aggregate intrinsic value of options exercised during the three months ended March 31, 2015 was $0.1 million.

The following table summarizes the stock option activity for all stock plans during the three months ended March 31, 2015:



	Options		Weighted- Average Exercise Price Per Share		(in years) Weighted- Average Contractual Life	(in thousands) Aggregate Intrinsic Value ⁽¹⁾
Outstanding at December 31, 2014	2,733,793		$	5.09	8.39	$	49,076
Granted	715,100		$	23.70
Exercised	(5,882	)	$	0.34
Canceled or forfeited	—		$	—
Outstanding at March 31, 2015	3,443,011		$	8.96	8.53	$	49,297
Exercisable at March 31, 2015	1,294,072		$	2.30	6.91	$	26,299

⁽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 March 31, 2015.

At March 31, 2015 and December 31, 2014, there were 117,647 shares of unvested common stock outstanding.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References+ Details

Grant Revenue	3 Months Ended
Grant Revenue	Mar. 31, 2015
Grant Revenue [Abstract]
Grant Revenue	GRANT REVENUE CPRIT Grant On July 27, 2011, the Company entered into a Cancer Research Grant Contract (Grant Contract) with the Cancer Prevention and Research Institute of Texas (CPRIT) under which CPRIT awarded a grant not to exceed approximately $5.7 million to be used by the Company for the execution of defined clinical development of BPX-501. In addition, CPRIT could award supplemental funding not to exceed ten percent of the total grant amount based upon the Company’s progress. The Grant Contract terminated on June 30, 2014. The terms of the Grant Contract require the Company to pay tiered royalties on revenues from sales and licenses of intellectual property facilitated by the Grant Contract. During the three months ended March 31, 2014, the Company incurred $0.5 million of expenses under the Grant Contract. As of March 31, 2015 and December 31, 2014, the Company had an outstanding grant receivable of $- million and $0.3 million respectively, for grant expenditures that were paid but had not yet been reimbursed. NIH Grant During 2014 and 2013, the Company was awarded $0.3 million and $0.4 million, respectively, under a grant from the National Institutes of Health (NIH). The awards cover the period from April 2013 through March 2015. The awards were made pursuant to the authority of 42 USC 241 42 CFR 52, and is subject to the requirements of the statute. Funds spent on the grant are reimbursed through monthly reimbursement requests. As of March 31, 2015 and 2014, funds spent under the grant were $0.1 million each. As of March 31, 2015 and December 31, 2014, the Company had a receivable of $0.1 million and $- million, respectively.

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. New Lease Agreement On May 6, 2015, the Company entered into a Lease Agreement (the Lease) with Sheridan Hills Developments L.P. (the Landlord) for the lease of three spaces of approximately 25,304 square feet (the Manufacturing Space), 705 square feet (the Interior Mechanical Space) and 808 square feet (the Exterior Mechanical Space), respectively, which the Company will use to enable in-house cell therapy manufacturing. The term of the Lease will begin on September 1, 2015 and continue for an initial term of five years, which may be renewed for five additional one-year periods. For the Manufacturing Space, the Company is required to remit base monthly rent of approximately $64,841 which will increase at an average approximate rate of 3.5% each year. For the Interior Mechanical Space, the Company is required to remit base monthly rent of approximately $1,219, which will increase at an average approximate rate of 5% each year. The monthly base rent for the Exterior Mechanical Space is approximately $471. The Company is also required to pay additional rent in the form of its pro rata share of certain specified operating expenses of the Landlord. An early termination right is available to the Company upon certain events, including the Landlord’s default on its obligations under the Lease. The newly leased spaces are located within the same building as the Company’s current headquarters in Houston, Texas. License Agreement On April 23, 2015, the Company and Academisch Ziekenhuis Leiden, also acting under the name Leiden University Medical Centre (Leiden), entered into a license agreement (the Agreement), pursuant to which Leiden granted to the Company an exclusive, worldwide license to its patent rights covering high affinity T-cell receptors targeting PRAME and POU2AF1 epitopes. The license granted under the Agreement is subject to certain restrictions and to Leiden’s retained right to use the licensed patents solely for academic research and teaching purposes, including research collaborations by Leiden with academic, non-profit research third parties; provided that Leiden provides 30 days advance written notice to the Company of such academic research collaborations. As consideration for the rights granted to the Company under the Agreement, the Company agreed to pay to Leiden an aggregate of EUR 75,000 in upfront fees within 30 days of the effective date of the Agreement. In addition, the Company agreed to pay to Leiden, beginning on the eighth anniversary of the effective date of the Agreement, annual minimum royalty payments of EUR 30,000. The Company also is required to make milestone payments to Leiden of up to an aggregate of EUR 1,025,000 for each of the first licensed product that is specific to PRAME and to POU2AF1. The Agreement additionally provides that the Company will pay to Leiden a royalty in the low single digits on net sales of products covered by the Agreement. If the Company enters into a sublicensing agreement with a third party related to a product covered by the Agreement, the Company agreed to pay Leiden a percentage ranging in the low double digits on all non-royalty income received from sublicensing revenue directly attributable to the sublicense, dependent on whether the Company is in phase 1/2, phase 2 or phase 3 at the time that the Company enters into any such sublicensing agreement. Under the Agreement, the Company and Leiden also agreed to enter into a sponsored research agreement, to be separately negotiated, pursuant to which the Company would be required to pay Leiden up to EUR 300,000over a three-year period during the term of the sponsored research agreement. The Agreement will expire upon the expiration of the last patent included in the licensed patent rights. The Agreement may be terminated earlier upon mutual written agreement between the Company and Leiden, and at any time by the Company upon six months written notice to Leiden. Leiden may terminate the Agreement in the event of a failure by the Company to pay any amounts due under the Agreement that remains uncured on the date that is 30 days after written notice of such failure. Either party may terminate the Agreement upon a material breach by the other party that remains uncured following 30 days after the date of written notice of such breach or upon certain insolvency events that remain uncured following the date that is 45 days after the date of written notice to a party of such insolvency event. The Company has evaluated all subsequent events and determined that there are no material recognized or unrecognized subsequent events requiring disclosure, other than those disclosed in this Report on Form 10-Q and as discussed in these notes to the financial statements.

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2015

Accounting Policies [Abstract]

Basis of Presentation

Use of Estimates


•	its stage of development;


•	its operational and financial performance;


•	the nature of its services and its competitive position in the marketplace;


•	the value of companies that it considers peers based on a number of factors, including similarity to the Company with respect to industry and business model;


•	the likelihood of achieving a liquidity event, such as an initial public offering and the nature and history of its business;


•	issuances of preferred stock and the rights, preferences, and privileges of its preferred stock relative to those of its common stock;


•	business conditions and projections;


•	the history of the Company and progress of its research and development efforts and clinical trials; and


•	the lack of marketability of its common stock.

Net Loss and Net Loss per Share of Common Stock Attributable to Common Stockholders

- Definition

Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.

+ References+ Details

- Definition

Disclosure of accounting policy for computing basic and diluted earnings or loss per share for each class of common stock and participating security. Addresses all significant policy factors, including any antidilutive items that have been excluded from the computation and takes into account stock dividends, splits and reverse splits that occur after the balance sheet date of the latest reporting period but before the issuance of the financial statements.

+ References+ Details

Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2015

Accounting Policies [Abstract]

Earnings Per Share, Potentially Dilutive Securities



Common Stock Equivalents:	March 31, 2015	March 31, 2014
Series A Preferred Stock Convertible Preferred Stock - as converted to common stock	—	1,496,782
Series B Preferred Stock Convertible Preferred Stock - as converted to common stock	—	4,791,740
Warrants to purchase common stock	355,392	473,031
Options to purchase common stock	3,443,011	1,584,692
	3,798,403	8,346,245

Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2015

Fair Value Disclosures [Abstract]

Fair Value, by Balance Sheet Grouping

Financial assets and liabilities that have recurring fair value measurements are shown below (in thousands):



	Balance at March 31, 2015		Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets:
Money market funds	$	181,636	$	181,636	$	—	$	—
Total	$	181,636	$	181,636	$	—	$	—



	Balance at December 31, 2014		Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets:
Money market funds	$	43,587	$	43,587	$	—	$	—
Total	$	43,587	$	43,587	$	—	$	—

- Definition

Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.

+ References+ Details

Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Allocation of Recognized Period Costs

Share-based compensation expense is included within operating expenses as follows (in thousands):



	Three Months Ended March 31,
	2015		2014
Research and development	$	599	$	66
General and administrative	890		10
Total share-based compensation	$	1,489	$	76

Valuation Assumptions

The fair value of the option grants during the three months ended March 31, 2015 and 2014 was estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:



	Three Months Ended March 31,
	2015		2014
Expected volatility	91.2	%	101.0	%
Expected term (in years)	6.08		6.25
Risk-free interest rate	1.6	%	2.7	%
Expected dividend yield	—	%	—	%

Schedule of Share-based Compensation, Stock Options, Activity

The following table summarizes the stock option activity for all stock plans during the three months ended March 31, 2015:



	Options		Weighted- Average Exercise Price Per Share		(in years) Weighted- Average Contractual Life	(in thousands) Aggregate Intrinsic Value ⁽¹⁾
Outstanding at December 31, 2014	2,733,793		$	5.09	8.39	$	49,076
Granted	715,100		$	23.70
Exercised	(5,882	)	$	0.34
Canceled or forfeited	—		$	—
Outstanding at March 31, 2015	3,443,011		$	8.96	8.53	$	49,297
Exercisable at March 31, 2015	1,294,072		$	2.30	6.91	$	26,299

Significant Accounting Policies Common Stock Equivalents (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	3,798,403	8,346,245
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	355,392	473,031
Series A Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	1,496,782
Series B Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	4,791,740
Equity Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	3,443,011	1,584,692

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References+ Details

Fair Value of Financial Instruments (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Money Market Funds, at Carrying Value	$ 181,636	$ 43,587
Assets, Fair Value Disclosure	181,636	43,587
Fair Value, Inputs, Level 1 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Money Market Funds, at Carrying Value	181,636	43,587
Assets, Fair Value Disclosure	181,636	43,587
Fair Value, Inputs, Level 2 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Money Market Funds, at Carrying Value	0	0
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Money Market Funds, at Carrying Value	0	0
Assets, Fair Value Disclosure	$ 0	$ 0

Accrued Expenses (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accrued Expenses [Abstract]
Accrued payroll	$ 0	$ 731
Commission on exercise of warrants	0	731
Medical facility fees	559	201
Patient treatment costs	125	128
License costs	52	50
Other	343	322
Total accrued expenses	$ 1,079	$ 2,163

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References+ Details

Stockholders' Equity (Details) (USD $)	0 Months Ended	1 Months Ended
Stockholders' Equity (Details) (USD $)	Dec. 04, 2014	Mar. 31, 2014	Mar. 31, 2015	Dec. 31, 2014
Stockholders' Equity Attributable to Parent [Abstract]
Preferred Stock, Shares Authorized			10,000,000	10,000,000
Preferred Stock, Shares Outstanding			0	0
Preferred Stock, Par or Stated Value Per Share			$ 0.01	$ 0.01
Common stock, authorized (shares)			200,000,000	200,000,000
Common stock, par value (usd per share)			$ 0.01	$ 0.01
Coomon stock issued in exercise of warrants, shares		393,523
Common stock issued in exercise of warrants, value		$ 200,700
Common stock issued in exercise of warrants, per share		$ 0.51
Stockholders' Equity, Reverse Stock Split	1-for-1.7 basis

Share-Based Compensation Narrative (Details) (USD $)	3 Months Ended
Share-Based Compensation Narrative (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Share-based Compensation Plans	4
Granted (shares)	715,100	10,293
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 28,900,000
Number of shares available for grant	550,000
Employee stock purchase plan cash contributions	101,000
Stock issued during period, shares, employee stock purchase plans	0
Equity instruments other than options, nonvested	117,647		117,647
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years 8 months 12 days
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options	2,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 100,000
2006 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	161,174
2011 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	2,425,561
2014 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	2,990,354

Share-Based Compensation Costs Recognized (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation	$ 1,489	$ 76
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation	599	66
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation	$ 890	$ 10

Share-Based Compensation Valuation Assumptions (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected volatility	91.20%	101.00%
Expected term (in years)	6 years 29 days	6 years 3 months
Risk-free interest rate	1.60%	2.70%
Expected dividend yield	0.00%	0.00%

Share-Based Compensation Stock Option Activity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Options
December 31, 2014 (shares)	2,733,793
Granted (shares)	715,100	10,293
Exercised (shares)	(5,882)
Canceled or forfeited (shares)	0
Outstanding at March 31, 2015 (shares)	3,443,011		2,733,793
Exercisable at March 31, 2015 (shares)	1,294,072
Weighted- Average Exercise Price Per Share
December 31, 2014 (usd per share)	$ 5.09
Granted (usd per share)	$ 23.70
Exercised (usd per share)	$ 0.00
Canceled or forfeited (usd per share)	$ 0.34
Outstanding at March 31, 2015 (usd per share)	$ 8.96		$ 5.09
Exercisable at March 31, 2015 (usd per share)	$ 2.30
Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Term, Outstanding	8 years 6 months 11 days		8 years 4 months 21 days
Weighted Average Remaining Contractual Term, Exercisable	6 years 10 months 28 days
Aggregate Intrinsic Value, Outstanding	$ 49,297		$ 49,076
Aggregate Intrinsic Value, Exercisable	$ 26,299

Grant Revenue (Details) (USD $)	3 Months Ended		0 Months Ended	3 Months Ended			3 Months Ended		12 Months Ended
Grant Revenue (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Jul. 27, 2011 Cancer Prevention and Research Institute of Texas [Member]	Mar. 31, 2014 Cancer Prevention and Research Institute of Texas [Member]	Mar. 31, 2015 Cancer Prevention and Research Institute of Texas [Member]	Dec. 31, 2014 Cancer Prevention and Research Institute of Texas [Member]	Mar. 31, 2015 National Institutes of Health Grant [Member]	Mar. 31, 2014 National Institutes of Health Grant [Member]	Dec. 31, 2014 National Institutes of Health Grant [Member]	Dec. 31, 2013 National Institutes of Health Grant [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenue from grants	$ 107,000	$ 552,000	$ 5,700,000						$ 300,000	$ 400,000
Percentage of grant			0.1
Costs and expenses				500,000			100,000	100,000
Grants receivable					$ 0	$ 300,000	$ 100,000		$ 0

Subsequent Events (Details) (Subsequent Event [Member])	0 Months Ended
Subsequent Events (Details) (Subsequent Event [Member])	Apr. 23, 2023 EUR (€)	May 06, 2015 USD ($) Location sqft
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Number of spaces in manufacturing area		3
Number of square feet of manufacturing space		25,304
Number of square feet of exterior mechanical space		705
Number of square feet of interior mechanical space		808
Operating lease, term of contract		5 years
Additional lease renewal periods		1 year
Lease monthly rent amount		$ 64,841.00
Average lease rent percentage annual increase		3.50%
Lease monthly rent amount - interior mechanical space		1,219.00
Annual lease rent percentage annual increase on interior mechanical space		5.00%
Lease monthly rent amount - exterior mechanical space		471.00
License agreement advance notice of research collaborations	30 days
License costs for rights granted under agreement	75,000
License agreement upfront fee period	30 days
Minimum annual royalty payments beginning on eighth anniversary	30,000
Milestone payments for first licensed products	1,025,000
License agreement sponsored research	€ 300,000
Term of payments under sponsored research agreement	3 years
License agreement termination notice	6 months
License agreement period of notice of failure on uncured items	30 days
License agreement termination period after written notice of failure	30 days
License agreement period after insolvency event	45 days

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments Contingencies and Guarantees [Text Block]	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.