View Filing Data

Years Ended December 31,

Intrinsic value of options exercised

$16.7 million

$8.5 million

$1.6 million

Fair value of awards vested

$9.6 million

$7.5 million

$3.0 million

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2015	Feb. 23, 2016	Jun. 30, 2015
Entity Information [Line Items]
Entity Registrant Name	NEWLINK GENETICS CORP
Entity Central Index Key	0001126234
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		28,858,536
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 929,606,561

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 195,620	$ 190,404
Certificates of deposit	2,180	12,393
Prepaid expenses and other current assets	4,954	8,333
State research and development credit receivable	0	13
Income tax receivable	0	8,763
Other receivables	5,388	3,716
Total current assets	208,142	223,622
Leasehold improvements and equipment:
Leasehold improvements	7,427	6,022
Computer equipment	2,582	1,399
Lab equipment	5,832	4,110
Contract manufacturing organization equipment	1,075	1,023
Total leasehold improvements and equipment	16,916	12,554
Less accumulated depreciation and amortization	(6,516)	(4,955)
Leasehold improvements and equipment, net	10,400	7,599
Total assets	218,542	231,221
Current liabilities:
Accounts payable	3,661	2,412
Accrued expenses	8,761	9,367
Income taxes payable	859	0
Current portion of unearned revenue	892	12,966
Current portion of deferred rent	96	84
Current portion of obligations under capital leases	13	35
Current portion of notes payable	558	157
Total current liabilities	14,840	25,021
Long term liabilities:
Royalty obligation payable to Iowa Economic Development Authority	6,000	6,000
Notes payable and obligations under capital leases	368	941
Unearned revenue	407	1,085
Deferred rent	1,153	1,238
Total long-term liabilities	7,928	9,264
Total liabilities	22,768	34,285
Stockholders' Equity
Blank check preferred stock, $0.01 par value: Authorized shares — 5,000,000 at December 31, 2015 and 2014; issued and outstanding shares — 0 at December 31, 2015 and 2014	0	0
Common stock, $0.01 par value: Authorized shares — 75,000,000 at December 31, 2015 and 2014; issued 28,838,176 and 27,991,242 at December 31, 2015 and 2014 and outstanding 28,814,142 and 27,980,849 at December 31, 2015 and December 31, 2014	288	280
Additional paid-in capital	276,610	236,838
Treasury stock, at cost: 24,034 and 10,393 shares at December 31, 2015 and 2014	(771)	(222)
Accumulated deficit	(80,353)	(39,960)
Total stockholders' equity	195,774	196,936
Total liabilities and stockholders' equity	$ 218,542	$ 231,221

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Stockholders' Equity:
Blank check preferred stock, par value	$ 0.01	$ 0.01
Blank check preferred stock, authorized shares	5,000,000	5,000,000
Blank check preferred stock, issued shares	0	0
Blank check preferred stock, outstanding shares	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	75,000,000	75,000,000
Common stock, issued shares	28,838,176	27,991,242
Common Stock
Stockholders' Equity:
Common stock, outstanding shares	28,814,142	27,980,849

Consolidated Statements of Operations - USD ($)	12 Months Ended
Consolidated Statements of Operations - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Grant revenue	$ 32,358,000	$ 6,642,000	$ 1,093,000
Licensing and collaboration revenue	36,143,000	165,950,000	0
Total operating revenues	68,501,000	172,592,000	1,093,000
Operating expenses:
Research and development	71,414,000	35,691,000	22,713,000
General and administrative	30,689,000	19,328,000	9,521,000
Total operating expenses	102,103,000	55,019,000	32,234,000
(Loss) income from operations	(33,602,000)	117,573,000	(31,141,000)
Other income and expense:
Miscellaneous (expense) income	(14,000)	0	112,000
Interest income	78,000	86,000	12,000
Interest expense	(105,000)	(26,000)	(33,000)
Other (expense) income, net	(41,000)	60,000	91,000
Net (loss) income before taxes	(33,643,000)	117,633,000	(31,050,000)
Income tax expense	(6,738,000)	(21,616,000)	(130,000)
Net (loss) income	$ (40,381,000)	$ 96,017,000	$ (31,180,000)
Basic (loss) earnings per share	$ (1.41)	$ 3.45	$ (1.23)
Diluted (loss) earnings per share	$ (1.41)	$ 3.09	$ (1.23)
Basic average shares outstanding	28,586,585	27,838,873	25,275,179
Diluted average shares outstanding	28,586,585	31,025,099	25,275,179

Consolidated Statements of Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Deficit Accumulated During the Development Stage [Member]	Retained Earnings
Balance at Dec. 31, 2012	$ 17,927	$ 210	$ 122,514	$ 0		$ (104,797)
Balance (shares) at Dec. 31, 2012		20,985,192
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	4,365		4,365
Exercise of stock options and restricted stock awards	442	$ 1	441
Exercise of stock options and restricted stock awards (shares)		107,541
Sale of shares under stock purchase plan	416	$ 1	415
Sale of shares under stock purchase plan (shares)		63,669
Stock issued	48,916	$ 46	48,870
Stock issued (shares)		4,600,000
Stock issued under ATM	17,441	$ 8	17,433
Stock issued under ATM (shares)		816,621
Net income (loss)	(31,180)					(31,180)
Balance at Dec. 31, 2013	58,327	$ 266	194,038	0		(135,977)
Balance (shares) at Dec. 31, 2013		26,573,023
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	8,613		8,613
Exercise of stock options and restricted stock awards	1,861	$ 4	1,857
Exercise of stock options and restricted stock awards (shares)		375,834
Sale of shares under stock purchase plan	466		466
Sale of shares under stock purchase plan (shares)		25,168
Stock issued under ATM	27,572	$ 10	27,562
Stock issued under ATM (shares)		1,017,217
Stock Repurchased During Period	(222)			(222)
Stock Repurchased During Period (shares)		(10,393)
Tax benefit from employee stock plan awards	4,302		4,302
Net income (loss)	96,017					96,017
Balance at Dec. 31, 2014	196,936	$ 280	236,838	(222)		(39,960)
Balance (shares) at Dec. 31, 2014		27,980,849
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	15,940		15,940
Exercise of stock options and restricted stock awards	3,355	$ 5	3,350
Exercise of stock options and restricted stock awards (shares)		477,284
Sale of shares under stock purchase plan	851		851
Sale of shares under stock purchase plan (shares)		40,248
Stock issued under ATM	13,534	$ 3	13,531
Stock issued under ATM (shares)		329,402
Stock Repurchased During Period	$ (561)			(561)
Stock Repurchased During Period (shares)		(14,183)
Treasury Stock, Shares, Retired	542
Stock Issued During Period, Value, Treasury Stock Reissued	$ 0			12	$ (12)
Tax benefit from employee stock plan awards	6,100		6,100
Net income (loss)	(40,381)					(40,381)
Balance at Dec. 31, 2015	$ 195,774	$ 288	$ 276,610	$ (771)		$ (80,353)
Balance (shares) at Dec. 31, 2015		28,814,142

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net (loss) income	$ (40,381)	$ 96,017	$ (31,180)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Share-based compensation	15,940	8,613	4,365
Depreciation and amortization	1,592	1,097	891
Loss on sale of fixed assets	0	0	2
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	3,379	(7,561)	134
State research and development credit receivable	13	316	213
Other receivables	(1,672)	(2,388)	(1,132)
Accounts payable and accrued expenses	245	7,898	843
Income taxes (receivable) payable	9,622	(8,892)	130
Unearned revenue	(12,752)	14,051	0
Deferred rent	(73)	(83)	(84)
Net cash (used in) provided by operating activities	(24,087)	109,068	(25,818)
Cash Flows From Investing Activities
Purchase of certificates of deposit	0	(17,377)	(249)
Maturity of certificates of deposit	10,213	5,233	1,494
Purchase of equipment	(3,995)	(1,700)	(1,386)
Net cash provided by (used in) investing activities	6,218	(13,844)	(141)
Cash Flows From Financing Activities
Issuance of common stock, net of offering costs	13,534	27,572	66,357
Issuance of common stock under share-based compensation plans	4,206	2,327	858
Excess tax benefits from share-based compensation awards	6,100	4,302	0
Repurchase of common stock	(561)	(222)	0
Proceeds from notes payable	0	97	0
Principal payments on notes payable	(158)	(154)	(149)
Payments under capital lease obligations	(36)	(33)	(66)
Net cash provided by financing activities	23,085	33,889	67,000
Net increase in cash and cash equivalents	5,216	129,113	41,041
Cash and cash equivalents at beginning of year	190,404	61,291	20,250
Cash and cash equivalents at end of year	195,620	190,404	61,291
Supplemental disclosure of cash flows information:
Cash paid for interest	105	26	34
Cash paid for taxes	4,814	26,443	0
Proceeds from icome tax refunds	13,796	0	0
Noncash financing and investing activities:
Purchased leasehold improvements and equipment in accounts payable and accrued expenses	398	409	0
Assets acquired under capital lease	$ 0	$ 0	$ 54

Description of Business Activities Level 1 (Notes)	12 Months Ended
Description of Business Activities Level 1 (Notes)	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business Activities	Description of Business Activities NewLink Genetics Corporation, or NewLink, was incorporated as a Delaware corporation on June 4, 1999 and initiated operations in April of 2000. In 2005, NewLink created a partially owned subsidiary, BioProtection Systems Corporation, or BPS. NewLink contributed certain licensing agreements and other intangible assets for BPS to create vaccines against potential biological terror threats. On January 7, 2011, NewLink acquired all of the minority interest in BPS, by merging a newly-formed subsidiary of NewLink with BPS, with BPS as the surviving corporation resulting in NewLink owning all the outstanding capital stock of BPS. In 2013, NewLink created a wholly owned subsidiary, NewLink International, or NI. NewLink plans to conduct all or a portion of its operations outside of the United States through NI. During 2014, NewLink created another wholly-owned subsidiary, NewLink Global, or NG, which was subsequently merged into NewLink during 2014. NewLink and its subsidiaries, or the Company, are devoting substantially all of their efforts toward research and development. The Company has incurred significant losses in all years since being incorporated, except for the year ended December 31, 2014, and has never generated revenue from commercial sales of its drugs. The accompanying financial statements as of and for the year ended December 31, 2015 have been prepared assuming the Company will continue as a going concern. The Company successfully raised net proceeds of $37.6 million from its IPO, completed a follow-on offering of its common stock raising net proceeds of $49.0 million, raised an additional $58.7 million in net proceeds from the ATM Offering prior to March 31, 2015. In connection with two license and collaboration agreements the Company entered into during 2014, the Company received a nonrefundable upfront cash payment of $150.0 million from Genentech Inc., a member of the Roche Group, or Genentech, in 2014, and a nonrefundable upfront cash payment of $30.0 million from Merck, Sharpe and Dohme Corp., or Merck, in 2014, as well as an additional milestone payment of $20.0 million from Merck in February 2015. The Company's cash and cash equivalents after these agreements and offerings are expected to be adequate to satisfy the Company's liquidity requirements into 2017, although not through commercialization and launch of revenue producing products. If available liquidity becomes insufficient to meet the Company’s operating obligations as they come due, the Company's plans include pursuing alternative funding arrangements and/or reducing expenditures as necessary to meet the Company’s cash requirements. However, there is no assurance that, if required, the Company will be able to raise additional capital or reduce discretionary spending to provide the required liquidity. Failure by the Company to successfully execute its plans or otherwise address its liquidity needs may have a material adverse effect on its business and financial position, and may materially affect the Company’s ability to continue as a going concern.

Significant Accounting Policies	12 Months Ended
Significant Accounting Policies	Dec. 31, 2015
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies (a) Use of Estimates The preparation of consolidated financial statements in conformity with U.S. generally accepted accounting principles, or U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. (b) Principles of Consolidation The consolidated financial statements include the financial statements of NewLink and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. (c) Immaterial Error Correction During the third quarter of 2015, we identified an immaterial error in the Company's 2014 income tax provision expense. Included in the consolidated balance sheet as of December 31, 2014 and the consolidated statement of operations and statement of cash flows for the year ending December 31, 2014 is an immaterial error correction related to the provision for income taxes. The income tax receivable as of December 31, 2014 has been decreased by $6.8 million and the income tax expense has been increased by $6.8 million. Due to this error, the Company’s net income and stockholders’ equity were both correspondingly overstated for the year ending December 31, 2014 by $6.8 million. The impact to basic and diluted earnings per share was a decrease of $0.25 and $0.22, respectively, for the year ending December 31, 2014. There was no impact to the net cash provided by operating activities in the consolidated statement of cash flows for the year ending December 31, 2014. The immaterial error correction also resulted in an increase in the Company's deferred tax asset and a corresponding increase to the valuation allowance as there is a full valuation allowance against net deferred tax assets due to the uncertainty of future recoverability. Management concluded that correcting the error would be immaterial to the fourth quarter results for 2014 and had no effect on the trend of financial results. Management also evaluated the impact of this error on our assessment of the effectiveness of internal control over financial reporting and concluded that our evaluation of controls as of December 31, 2014 remains effective. (d) Cash and Cash Equivalents For the purposes of the consolidated statements of cash flows, the Company considers all highly liquid debt instruments with an original maturity of three months or less to be cash equivalents. Cash and cash equivalents of $195.6 million and $190.4 million at December 31, 2015 and 2014, respectively, consist of checking accounts, money market accounts and treasury bills. (e) Certificates of Deposit Certificates of deposit have original maturities of greater than three months. Certificates of deposit are classified as held-to-maturity with due dates through 2016 and are presented at amortized cost, which approximates fair value. (f) Leasehold Improvements and Equipment, and Deferred Rent Leasehold improvements and equipment are capitalized as the Company believes they have alternative future uses and are stated at cost. Equipment under capital leases is stated at the present value of minimum lease payments. Depreciation on all leasehold improvements and equipment is calculated on the straight-line method over the shorter of the lease term or estimated useful life of the asset. Computer equipment has useful lives of three to five years, lab equipment has a useful life of five years and contract manufacturing organization equipment has a useful life of five years. Deferred rent reflects improvement allowances from the Company's lessors deferred to be recognized as part of lease expense over the remaining term of the lease, which is recognized on a straight-line basis. Total deferred rents were $1.2 million and $1.3 million as of December 31, 2015 and 2014, respectively. (g) Impairment of Long-Lived Assets Long-lived assets are reviewed for impairment whenever changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset group to future net undiscounted cash flows expected to be generated by the asset group, primarily relating to proceeds for selling the assets. If such assets are considered to be impaired, the impairment to be recognized is measured at the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell. (h) Revenue Recognition The Company recognizes revenue for the performance of services or the shipment of products when each of the following four criteria is met: (1) persuasive evidence of an arrangement exists; (2) products are delivered or as services are rendered; (3) the sales price is fixed or determinable; and (4) collectability is reasonably assured. The Company follows ASC 605-25, Revenue Recognition - Multiple-Element Arrangements and ASC 808, Collaborative Arrangements , if applicable, to determine the recognition of revenue under our license and collaborative research, development and commercialization agreements. The terms of these agreements generally contain multiple elements, or deliverables, which may include (1) licenses to our intellectual property, (2) materials and technology, (3) clinical supply, and/or (4) participation on joint research or joint steering committees. The payments we may receive under these arrangements typically include one or more of the following: non-refundable, up-front license fees; funding of research and/or development efforts; amounts due upon the achievement of specified milestones; and/or royalties on future product sales. ASC 605-25 provides guidance relating to the separability of deliverables included in an arrangement into different units of accounting and the allocation of arrangement consideration to the units of accounting. The evaluation of multiple-element arrangements requires management to make judgments about (1) the identification of deliverables, (2) whether such deliverables are separable from the other aspects of the contractual relationship, (3) the estimated selling price of each deliverable, and (4) the expected period of performance for each deliverable. To determine the units of accounting under a multiple-element arrangement, management evaluates certain separation criteria, including whether the deliverables have stand-alone value, based on the relevant facts and circumstances for each arrangement. Management then estimates the selling price for each unit of accounting and allocates the arrangement consideration to each unit utilizing the relative selling price method. The allocated consideration for each unit of accounting is recognized over the related obligation period in accordance with the applicable revenue recognition criteria. If there are deliverables in an arrangement that are not separable from other aspects of the contractual relationship, they are treated as a combined unit of accounting, with the allocated revenue for the combined unit recognized in a manner consistent with the revenue recognition applicable to the final deliverable in the combined unit. Payments received prior to satisfying the relevant revenue recognition criteria are recorded as unearned revenue in the accompanying balance sheets and recognized as revenue when the related revenue recognition criteria are met. The Company typically receives non-refundable, up-front payments when licensing our intellectual property, which often occurs in conjunction with a research and development agreement. If management believes that the license to our intellectual property has stand-alone value, the Company generally recognizes revenue attributed to the license upon delivery provided that there are no future performance requirements for use of the license. When management believes that the license to our intellectual property does not have stand-alone value, the Company would recognize revenue attributed to the license on a straight-line basis over the contractual or estimated performance period. When the performance period is not specifically identifiable from the agreement, the Company would estimate the performance period based upon provisions contained within the agreement, such as the duration of the research or development term. For payments payable on achievement of milestones that do not meet all of the conditions to be considered substantive, the Company recognizes a portion of the payment as revenue when the specific milestone is achieved, and the contingency is removed. Other contingent event-based payments for which payment is either contingent solely upon the passage of time or the result of collaborator's performance are recognized when earned. The Company receives payments from government entities under its grants and contracts with the National Institute of Health, the Department of Defense, and the United States Department of Health and Human Services. These agreements provide the Company cost reimbursement plus a percentage for certain types of expenditures in return for research and development activities over a contractually defined period. Grant revenues are recognized in the period during which the related costs are incurred, provided that the conditions under which the costs submitted or to be submitted for reimbursement have been met and the Company has only perfunctory obligations outstanding. During the years ended December 31, 2015, 2014, and 2013, the Company has earned $32.4 million, $6.6 million, and $1.1 million in grant revenue, respectively. We had $4.1 million and $3.7 million of receivables from the government contracts recorded in other receivables and $3.6 million and $7.5 million of unbilled expenses relating to the government contracts recorded in prepaid expenses and other assets on the balance sheet for the years ended December 31, 2015 and 2014, respectively. (i) Expenses Accrued Under Contractual Arrangements with Third Parties; Accrued Clinical Expenses The Company estimates its accrued expenses through a process of reviewing open contracts and purchase orders, communicating with personnel to identify services that have been performed and estimating the level of service performed and the associated cost incurred for the service that may not be invoiced from the provider. The estimates of accrued expenses as of each balance sheet date are based on facts and circumstances known at that time. Such estimates are periodically confirmed with the service providers to verify accuracy. The Company bases its expenses related to clinical trials on estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and contract research organizations that conduct and manage clinical trials on behalf of the Company. Invoicing from third-party contractors for services performed can lag several months. The Company accrues the costs of services rendered in connection with third-party contractor activities based on its estimate of management fees, site management and monitoring costs and data management costs as contracted. Differences between actual clinical trial costs and estimated clinical trial costs are adjusted for in the period in which they become known through operations. (j) Research and Development Research and development costs are expensed as incurred. Certain research and development expenses are refundable from the state of Iowa without regard to income. State research and development credits of $450,000 and $748,000 at December 31, 2015 and 2014, respectively, are reflected as a reduction in income taxes on the accompanying consolidated statements of operations. State research and development credits of $329,000 at December 31, 2013, are reflected as a reduction of research and development expenses on the accompanying consolidated statements of operations. (k) Patents The Company generally applies for patent protection on processes and products. Patent application costs are expensed as incurred as a component of general and administrative expense, as recoverability of such expenditures is uncertain. (l) Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operating results in the period that includes the enactment date. Management assesses the realizability of deferred tax assets and records a valuation allowance if it is more likely than not that all or a portion of the deferred tax assets will not be realized. Income tax expense was 20.0% of loss before income taxes in 2015. A valuation allowance of $20.7 million as of December 31, 2015 offsets our net deferred tax assets. The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. As of December 31, 2015 and 2014, the Company has not recognized any uncertain tax positions. (m) Share-Based Compensation The Company is required to estimate the grant-date fair value of stock options, stock awards and restricted stock issued to employees and recognize this cost over the period these awards vest. The Company estimates the fair value of each award granted using the Black-Scholes option pricing model. The Black-Scholes model requires the input of assumptions, including the expected stock price volatility, the calculation of expected term and the fair value of the underlying common stock on the date of grant, among other inputs. Generally, the Company has issued employee awards that vest over time. For these awards, the Company records compensation cost on a straight-line basis over the vesting period. The Company issues awards, which typically vest 20% to 25% on the first anniversary date of issuance with the remaining options vesting ratably over the next 36 to 48 months, as determined by the Board of Directors at the time of grant. The Company calculates the fair value of the award on the grant date, which is the date the award is authorized by the Board of Directors or Chief Executive Officer and the employee has an understanding of the terms of the award. The Company has issued awards to nonemployee consultants and advisers. All grants to nonemployees are valued using the same fair value method that we use for grants to employees. The compensation cost on these awards is measured each period until vesting, and is recognized through the earlier of the vesting of the award or completion of services by the nonemployee. Following is a description of the inputs for the Black-Scholes model: Exercise Price The Company’s stock options granted prior to the IPO were granted with an exercise price as determined by the NewLink Board of Directors in good faith with the assistance of a third-party appraisal report and an evaluation of milestones achieved. Subsequent to the IPO, the Company uses the quoted market price as listed on the public exchange on the date of grant. If Incentive Stock Options are granted to a 10% stockholder in the Company, the exercise price shall not be less than 110% of the common stock’s fair market value on the date of grant. Expected Term (in Years) The expected term of a stock option is the period of time for which the option is expected to be outstanding. The Company uses historical exercise and option expiration data to estimate the expected term for the Black-Scholes grant-date valuation. Risk-Free Interest Rate The Company uses the average yield on current U.S. Treasury instruments with terms that approximate the expected term of the stock options being valued. Expected Dividend Yield The expected dividend yield for all of the Company’s stock option grants is 0%, as the Company has not declared a cash dividend since inception and has no plans to declare a dividend. Expected Volatility The Company estimates future expected volatility for each stock option valuation utilizing volatility rates of similar publicly traded companies considered to be in the same peer group. Prior to 2015, the Company used a combination of its own data and peer group data to compute our volatility. Beginning in 2015, the Company began to use its historical stock price volatility. The volatility is calculated over a period of time commensurate with the expected term for the options granted. Forfeitures The share-based compensation expense has been reduced for estimated forfeitures. The estimated forfeiture rate is based on historical experience of the Company’s option plan, which the Company expects to continue at the current level, and any adjustments in the forfeiture rate in the future will result in a cumulative adjustment in the period that this estimate is changed. Ultimately, the total compensation expense recognized for any given stock-based award over its vesting period will only be for those shares that actually vest. (n) Segments The Company operates in one segment. The Company conducts research and development activities based from facilities located in Ames, Iowa. NewLink and BPS have corporate headquarters in Ames, Iowa and Austin, Texas. The Company conducts preclinical and clinical research in the biopharmaceutical industry. The chief operating decision maker uses cash flow as the primary measure to manage the business and management does not segment its business for internal reporting or decision-making. (o) Financial Instruments and Concentrations of Credit Risk The fair values of cash and cash equivalents, certificates of deposit, receivables and accounts payable, which are recorded at cost, approximate fair value based on the short-term nature of these financial instruments. The fair value of notes payable and capital lease obligations was $941,000 and $1.1 million as of December 31, 2015 and 2014, respectively, and was determined using Level 2 inputs. The Company is unable to estimate the fair value of the royalty obligation based on future product sales as the timing of payments, if any, is uncertain. Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, and certificates of deposit. Cash and cash equivalents are held by financial institutions and are federally insured up to certain limits. At times, the Company’s cash and cash equivalents balance exceeds the federally insured limits. To limit the credit risk, the Company invests its excess cash primarily in high quality securities such as money market funds. (p) Earnings per share (EPS) The Company computes basic EPS attributable to the Company's common stockholders by dividing net income (loss) attributable to the Company by our weighted-average common shares outstanding, during the period. Diluted EPS reflects the potential dilution beyond shares for basic EPS that could occur if securities or other contracts to issue common stock were exercised, converted into common stock, or resulted in the issuance of common stock that would have shared in our earnings. The Company computes basic and diluted EPS using net income (loss) attributable to the Company's common stockholders, and its actual weighted-average shares. (q) Concentration of Revenue Prior to 2014, the Company's revenue was primarily obtained from government research grants. Genentech and Merck accounted for 21.5% and 31.3%, respectively, of the $68.5 million of revenue for the year ended December 31, 2015. Genentech, a member of the Roche Group and Merck Sharpe and Dohme Corp., or Merck, accounted for 78.9% and 17.2%, respectively, of the $172.6 million of revenue earned for the year ended December 31, 2014, with the remainder obtained from government grants. (r) Recent Accounting Pronouncements In November 2015, the Financial Accounting Standards Board, or FASB, issued FASB Accounting Standards Update (ASU) No. 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes. The amendments in this update require that deferred tax liabilities and assets be classified as noncurrent in a classified statement of financial position. This ASU is effective for financial statements issued for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Earlier application is permitted as of the beginning of an interim or annual reporting period. The Company early adopted this ASU on a prospective basis in the fourth quarter of fiscal 2015. Prior periods were not retrospectively adjusted. As of December 31, 2015 and 2014, all deferred taxes were fully offset by a valuation allowance, therefore adoption of this guidance did not have an impact on the presentation of our consolidated financial statements. On May 28, 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2018; however, early adoption at January 1, 2017, is permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected a transition method, nor has it determined the effect of the standard on its ongoing financial reporting.

Leases

12 Months Ended

Dec. 31, 2015

Leases [Abstract]

Leases

(a) Capital Leases

The following is an analysis of the leased property under capital leases by major class (in thousands):



	Asset balances at December 31,
Class of property	2015			2014
Lab equipment	$	489		$	489
Leasehold improvements	27			27
Computer equipment	54			54
Total property under capital leases	570			570
Less accumulated depreciation and amortization	(472		)	(384		)
Capital leased assets, net	$	98		$	186

The depreciation and amortization reflected above has been recorded in both research and development and general administrative expense in the consolidated statements of operations.

The following is a schedule by years of the future minimum lease payments under capital leases together with the present value of the net minimum lease payments as of December 31, 2015 (in thousands):



Year ending December 31:
2016	$	13
2017	—
Total minimum lease payments	13
Less amount representing interest	(1		)
Present value of net minimum lease payments	$	12

(b) Operating Leases

The Company has certain facility leases with terms ranging between one and five years. Lease expense is recognized on a straight-line basis. Rental expense for operating leases during the years ended December 31, 2015, 2014 and 2013, was $1.7 million, $1.2 million, and $766,000 respectively, including those with terms less than one year, and has been included in both research and development and general and administration in the consolidated statements of operations.

Future minimum lease payments under the noncancelable operating leases (with initial or remaining lease terms in excess of one year) as of December 31, 2015 are as follows (in thousands):



Year ending December 31:
2016	$	1,417
2017	991
2018	509
2019	452
2020	38
Thereafter	—
Total	$	3,407

Long-Term Debt Conversion to Royalty Obligation	12 Months Ended
Long-Term Debt Conversion to Royalty Obligation	Dec. 31, 2015
Long-Term Debt Conversion to Royalty Obligation [Abstract]
Long-Term Debt Conversion to Royalty Obligation	Long-Term Debt and Conversion to Royalty Obligation March 2005 Iowa Department of Economic Development Loan In March 2005, the Company entered into a $6.0 million forgivable loan agreement with the Iowa Department of Economic Development, or the IDED. Under the agreement, in the absence of default, there were no principal or interest payments due until the completion date for the project. The balance outstanding under the loan agreement was $6.0 million as of December 31, 2011. This loan was converted into a royalty obligation under the terms of a settlement agreement entered into on March 26, 2012, or the IEDA Agreement, with the Iowa Economic Development Authority (the IEDA), as successor in interest to the IDED. March 2012 IEDA Royalty Obligation Under the terms of the IEDA Agreement the Company agreed to pay a 0.5% royalty on future product sales up to a cap of $6.8 million in exchange for IDED’s release of the Company's job creation and project expenditure obligations and their release of the security interest in substantially all of the Company's assets. As no payments are expected in the next 12 months, the entire accrued royalty obligation of $6.0 million is considered long-term as of December 31, 2015. 2009 and 2012 Iowa State University Research Park Notes In 2009, the Company executed a promissory note in favor of Iowa State University Research Park, or ISURP, in an original principal amount of $800,000, which is due in monthly installments through March, 2018. The note represents amounts owed by the Company to ISURP for certain improvements that were made to facilities the Company leases from ISURP. The principal and interest owed under the note is amortized over an eight-year period. Interest is payable monthly under this promissory note, initially at a rate of 3.0% per annum and increasing to 5.0% per annum after five years from the date the improvements were completed. ISURP may accelerate all amounts owed under the note upon an event of default, including the Company’s uncured material breach of the terms of the note or the lease or upon early termination of the lease. In the event of a default under the note, amounts owed under the note will bear interest at 8.0% per annum. The balance outstanding under the 2009 note was $246,000 and $348,000 at December 31, 2015 and December 31, 2014, respectively. In 2012, the Company executed a promissory note in favor of ISURP in an original principal amount of $456,000, which is due in monthly installments through September 2020. The note represents amounts owed by the Company to ISURP for certain additional improvements that were made to facilities the Company leases from ISURP. The principal and interest owed under the note is amortized over an eight-year period. Interest is payable monthly under this promissory note, initially at a rate of 3.0% per annum and increasing to 5.0% per annum after five years from the date the improvements were completed. ISURP may accelerate all amounts owed under the note upon an event of default, including the Company’s uncured material breach of the terms of the note or the lease or upon early termination of the lease. In the event of a default under the note, amounts owed under the note will bear interest at 8.0% per annum. The balance outstanding under the 2012 note was $284,000 and $339,000 at December 31, 2015 and December 31, 2014, respectively. March 2010 City of Ames Forgivable Loan In March 2010, the Company entered into a $400,000 forgivable loan agreement with the City of Ames, Iowa and the Ames Chamber of Commerce, jointly, as lenders. The project provides the Company with financial assistance to construct new facilities within the Ames city limits. In the absence of a default, there are no principal or interest payments due until March 10, 2016. The project calls for the Company to create or retain at least 150 full-time positions located in Ames, Iowa. The agreement also required the Company to enter into a five-year building lease with the option for extension for an additional five years of not less than 20,000 square feet within the corporate limits of the City of Ames by March 10, 2015, which requirement the Company met by the March 10, 2105 deadline. If, as of March 10, 2016, the Company has fulfilled the terms of the loan agreement, the loan will be forgiven. If on March 10, 2016, the Company has failed to create or retain at least 150 full-time jobs in Ames, Iowa, the Company will be required to repay approximately $3,100 per job not created or retained following such date. As of December 31, 2015, $397,000 of the total $400,000 forgivable loan was advanced to the Company. As of December 31, 2015, the Company had created 150 full-time jobs in Ames, Iowa. In the event of default, including failure to repay any amounts under the loan when due, the Company will be required to repay the note, including 6.5% interest per annum, beginning at the date of default.

License and Research Collaboration Agreements	12 Months Ended
License and Research Collaboration Agreements	Dec. 31, 2015
Revenue Recognition [Abstract]
License and Research Collaboration Agreements	License and Research Collaboration Agreements Genentech, a Member of the Roche Group In October 2014, the Company entered into a worldwide exclusive collaboration and license agreements with Genentech for the development and commercialization of GDC-0919, one of NewLink's clinical stage IDO pathway inhibitors. The parties also entered into a research collaboration for the discovery of next generation IDO/TDO compounds to be developed and commercialized under this agreement. Under the terms of the agreement, the Company received a nonrefundable upfront cash payment of $150.0 million from Genentech and is eligible to receive additional payments of over $1.0 billion upon achieving certain GDC-0919 and Next Generation Product Development regulatory development, international patent acceptance, country marketing approval, and sales-based milestones. The Company is also eligible to receive escalating double-digit royalty payments on potential commercial sales of multiple products by Genentech. The Company is obligated to deliver multiple non-contingent deliverables related to the GDC-0919 upfront cash payment. These deliverables include the GDC-0919 development and commercialization license, research license, program materials and technology, clinical supply of GDC-0919 product, manufacturing technology, participation in a joint research committee, or JRC, and providing an alliance manager. The GDC-0919 development and commercialization license and research license are separate deliverables, but without the ability to develop GDC-0919, the ability to perform research on the compound would not benefit Genentech. Therefore, the Company believes that the value of the development and commercialization license cannot be separated from the research license value and the two are valued together. The other deliverables qualify as separate units of accounting. The respective standalone value from each of these deliverables has been determined by applying the best estimated selling price method and the revenue was allocated based on the relative selling price method with revenue recognition timing to be determined either by delivery or the provision of service. The estimated selling price determination required the use of significant estimates. To determine the stand-alone value of the license, we considered the negotiation discussions that led to the final terms of the agreement. The Company utilized historical cost plus an estimated gross margin to estimate the selling price for program materials and technology, manufacturing technology, clinical supply, participation in a JRC, and participation of an alliance manager. The program materials and technology, clinical supply of GDC-0919, participation in a JRC and participation of an alliance manager are expected to be delivered throughout the duration of the agreement. The license and manufacturing technology was delivered shortly after the effective date of the agreement. The Company recognized revenue under this agreement of $14.7 million for the year ended December 31, 2015. This amount includes the recognition of $9.4 million for program materials and technology transfer, $2.5 million for the clinical supply of GDC-0919 product, $151,000 for participation in the JRC, and $502,000 for providing an alliance manager to the collaboration. Additionally, $2.1 million was recognized for amounts received as reimbursement for the Company's employees working on the project. Revenues of $1.2 million remain deferred as of December 31, 2015 for deliverables identified within the collaboration and license agreement that have not yet been completed in their entirety. The Company recognized revenue under this agreement of $136.2 million for the year ended December 31, 2014 associated with license and manufacturing technology transfer deliverables, which were completed in their entirety. In accordance with the Company’s continuing performance obligation, $13.8 million of the initial $150.0 million upfront payment was deferred as of December 31, 2014. Per the agreement, the up-front payment provides no general right of return for any non-contingent deliverable and no portion of any revenue recognized is refundable. The Company will apply the contingency-adjusted performance model to recognize revenue related to potential future milestones under the agreement, therefore, revenue will only be recognized upon the achievement of a milestone. The Company is eligible to receive from Genentech tiered royalty payments based on product sales, with royalty rates varying based on the territory of the sales, the product, the licenses incorporated in the development, and the opt-in by the Company during development. Royalties will be accounted for as contingent revenue and will be recognized as earned in accordance with contract terms, when Genentech results are reported, the amount can be reasonably estimated, and collectability is reasonably assured. Merck Sharpe & Dohme Corp. In November 2014, the Company entered into a licensing and collaboration agreement with Merck to develop, manufacture and commercialize rVSV-ZEBOV, an Ebola vaccine the Company licensed from the Public Health Agency of Canada, or PHAC. Under the terms of the agreement, the Company granted Merck an exclusive, royalty-bearing license to the rVSV-ZEBOV and related technology. NewLink received a $30.0 million non-refundable, upfront payment in December 2014, and was also eligible for a one-time $20.0 million non-refundable milestone payment upon the initiation of the pivotal clinical trial using the current rVSV-ZEBOV vaccine product as one arm of the trial. In February 2015, this milestone was achieved and the Company received the milestone payment. In addition, NewLink can receive escalating royalties on potential commercial sales by Merck of the current product candidate ranging from single-digit to double-digits on the rVSV-ZEBOV license agreement product sales and escalating royalties on potential commercial sales by Merck of products other than current products within the Company’s patent rights ranging from low to high single-digit, on increasing levels of annual net sales worldwide. Merck will lead the development of rVSV-ZEBOV and any other rVSV-based viral hemorrhagic fever, or VHF, vaccine product candidates in order to create a marketable product safe for human use. The Company is obligated to deliver multiple non-contingent deliverables related to the rVSV-ZEBOV upfront cash payment. These deliverables include the license, information and know-how, technology transfer, participation in a joint steering committee, or JSC, and providing a project leader. These deliverables qualify as separate units of accounting. The respective standalone value from each of these deliverables has been determined by applying the best estimated selling price method and the revenue allocated based on the relative selling price method with revenue recognition timing to be determined either by delivery or the provision of service. The determination of the best estimated selling price required the use of significant estimates. To determine the stand alone value of the license, the Company considered the negotiation discussions that led to the final terms of the agreement. The Company used historical cost plus an estimated gross margin to estimate the selling price for information and know-how, technology transfer, participation in the JSC, and providing a project leader. The technology transfer, participation in the JSC and providing a project leader are expected to be delivered throughout the duration of the agreement. The license and information and know-how was delivered shortly after the effective date of the agreement. The Company recognized revenue under this agreement of $21.4 million for the year ended December 31, 2015. This amount includes the recognition of the $20.0 million milestone payment from Merck after notification from Merck that the milestone event specified in the license and collaboration agreement between the two companies relating to the further development of the rVSV-EBOV vaccine product candidate had been achieved. The milestone pertains to the initiation of a key clinical trial for the vaccine. The Company recognized $170,000 in revenue relating to the other deliverables and $1.2 million for the reimbursement of costs associated with the Ebola clinical trials not reimbursed under its government contracts. Revenue of $53,800 remains deferred as of December 31, 2015 and will be recognized in future years as delivery occurs. The Company recognized revenue under this agreement of $29.6 million for the year ended December 31, 2014 associated with license and information and know-how, which were completed in their entirety, and also recognized an additional $170,000 associated with the remaining deliverables. In accordance with the Company’s continuing performance obligations, $232,000 of the $30.0 million upfront payment was deferred as of December 31, 2014. Per the agreement, the up-front payment provides no general right of return for any non-contingent deliverable and no portion of any revenue recognized is refundable. The Company is eligible to receive from Merck tiered royalty payments based on product sales, with royalty rates varying based on Merck sales of the current rVSV-ZEBOV vaccine product and Merck sales of other products included within the Company’s patent rights. Royalties will be recognized as earned in accordance with contract terms, when Merck results are reported, the amount can be reasonably estimated, and collectability is reasonably assured.

Common Stock	12 Months Ended
Common Stock	Dec. 31, 2015
Common Stock [Abstract]
Common Stock	Common Stock The holders of common stock are entitled to one vote per share on all matters to be voted upon by the Company stockholders. Subject to preferences applicable to outstanding preferred stock, the holders of common stock are entitled to receive ratably such dividends, if any, as may be declared from time to time by the Company's Board of Directors. In the event of liquidation, dissolution, or winding up of the Company, the holders of common stock are entitled to share ratably in all assets remaining after payment of liabilities subject to prior distribution rights of the preferred stock.

Preferred Stock	12 Months Ended
Preferred Stock	Dec. 31, 2015
Preferred Stock [Abstract]
Preferred Stock	Preferred Stock As of December 31, 2015 and 2014, the Company had no outstanding preferred stock. The Company's Board of Directors has the authority to issue up to 5,000,000 shares of preferred stock in one or more series and to fix the voting power and such designations, preferences, and rights of such series, subject to approval of outstanding preferred series shareholders.

Common Stock Equity Incentive Plans

12 Months Ended

Dec. 31, 2015

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

Common Stock Equity Incentive Plan

Common Stock Equity Incentive Plans

In April 2000, the stockholders approved NewLink’s 2000 Equity Incentive Plan. as amended, or the 2000 Plan, and in July 2009, the stockholders approved NewLink’s 2009 Equity Incentive Plan, as amended, or the 2009 Plan. Following the approval of the 2009 Plan, all options outstanding under the 2000 Plan were effectively included under the 2009 Plan. Under the provisions of the 2009 Plan, NewLink may grant the following types of common stock awards:


•	Incentive Stock Options


•	Nonstatutory Stock Options


•	Restricted Stock Awards


•	Stock Appreciation Rights

Awards under the 2009 Plan, as amended, may be made to officers, employees, members of the NewLink Board of Directors, advisors, and consultants to NewLink. As of December 31, 2015 there were 7,919,109 shares of common stock authorized for the 2009 Plan and 774,499 shares remained available for issuance. As of December 31, 2014 there were 6,799,854 shares of common stock authorized for the 2009 Plan and 654,935 shares remained available for issuance.

On January 7, 2011, stockholders authorized an increase of 714,286 shares of common stock available for issuance under the 2009 Plan. On January 1, 2013, an additional 838,375 shares of common stock were added to the shares reserved for future issuance under the 2009 Plan. On January 1, 2014, an additional 1,066,340 shares of common stock were added to the shares reserved for future issuance under the 2009 Plan. On January 1, 2015 an additional 1,119,255 shares of common stock were added to the shares reserved for future issuance under the 2009 Plan. Subsequent to year end, on January 1, 2016, an additional 1,152,565 shares of common stock were added to the shares reserved for future issuance under the 2009 plan. The shares added to the reserve on January 1, 2013, January 1, 2014, January 1, 2015, and January 1, 2016 were added pursuant to an “evergreen provision”, in accordance with which, on January 1 of each year, from 2012 to (and including) 2019, a number of shares of common stock in an amount equal to 4% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or such lesser amount of shares (or no shares) approved by the Company's Board of Directors, was added or will be added to the shares reserved under the 2009 Plan.

Under the terms of the Company's 2010 Non-Employee Directors’ Stock Option Plan, as amended, or the Directors’ Plan, which became effective on November 10, 2011, 238,095 shares of common stock were reserved for future issuance. On May 9, 2013, an additional 161,905 shares of common stock were added to the reserve. As of December 31, 2015, 106,640 shares remained available for issuance under the Directors' Plan.

Under the terms of the Company's 2010 Employee Stock Purchase Plan, as amended, or the 2010 Purchase Plan, which became effective on November 10, 2011, 214,285 shares of common stock were reserved for future issuance. On May 9, 2013, an additional 185,715 shares of common stock were added to the reserve. As of December 31, 2015, 231,392 shares remained available for issuance under the plan. During the years ended December 31, 2015 and 2014, 40,248 and 25,168 shares of common stock, respectively, were purchased under the terms of the 2010 Purchase Plan.

Share-based Compensation

Share-based employee compensation expense for the years ended December 31, 2015, 2014 and 2013, was $15.9 million, $8.6 million, and $4.4 million, respectively, and is allocated between research and development and general and administrative expenses within the consolidated statements of operations. As of December 31, 2015, the total compensation cost related to unvested option awards not yet recognized was $35.8 million and the weighted average period over which it is expected to be recognized was 3 years. The total income tax benefit recognized in the consolidated statements of operations for stock-based compensation arrangements was $7.8 million, $3.7 million and $0 for the years ended December 31, 2015, 2014 and 2013, respectively.

Stock Options

The Company's Board of Directors determines the vesting period for each stock option award. Stock options awarded to date under the 2009 Plan vest monthly or vest 20% or 25% on the first anniversary date of issuance with the remaining options vesting ratably over the next 36 to 48 months, though some options have effective vesting periods that begin prior to the date of grant. In such cases, compensation expense was recognized for the vested portion of the award upon grant. The stock options may include provisions for early exercise of options. If any shares acquired are unvested, they are subject to repurchase at the Company’s discretion until they become vested.

The following table summarizes the stock option activity for the year ended December 31, 2015:



	Number of options		Weighted average exercise price		Weighted average remaining contractual term (years)
Outstanding at beginning of period	5,098,311		$	9.46
Options granted	1,019,445		42.57
Options exercised	(422,767	)	7.94
Options forfeited	(48,403	)	36.70
Options expired	(106	)	14.19
Outstanding at end of period	5,646,480		$	15.11	6.0
Options exercisable at end of period	4,039,770		$	8.04	4.9

Based on the December 31, 2015 price of $36.39 per share, the intrinsic value of stock options outstanding at December 31, 2015, was $126.2 million, of which $115.0 million and $11.2 million related to stock options that were vested and unvested, respectively, at that date.

The following table summarizes options that were granted during the years ended December 31, 2015, 2014 and 2013, and the range of assumptions used to estimate the fair value of those stock options using a Black-Scholes valuation model:



	Years Ended December 31,
	2015	2014	2013
Number of options granted	1,019,445	974,555	860,250
Risk-free interest rate	1.51%-2.00%	1.73%-2.24%	.89%-2.14%
Expected dividend yield	—	—	—
Expected volatility	62.5%-67.3%	57.4%-68.3%	61.4%-67.3%
Expected term (in years)	5.9-7.0	6.0-7.0	4.8-7.0
Weighted average grant-date fair value per share	$26.36	$14.80	$7.50

The following table summarizes the intrinsic value of options exercised and the fair value of awards vested during the years ended December 31, 2015, 2014 and 2013:

The fair value of options vested for the year ended December 31, 2015, includes the accelerated vesting as a result of an employee's departure from the Company of $2.8 million. The fair value of options vested for the year ended December 31, 2014, includes $1.7 million in share-based compensation resulting from the vesting in full of one employee's options upon the employee's termination that occurred during 2014.

Restricted Stock

Restricted stock is common stock that is subject to restrictions, including risks of forfeiture, determined by the plan committee of the Board of Directors in its sole discretion, for so long as such common stock remains subject to any such restrictions. A holder of restricted stock has all rights of a stockholder with respect to such stock, including the right to vote and to receive dividends thereon, except as otherwise provided in the award agreement relating to such award. Restricted stock awards are equity classified within the consolidated balance sheets. The fair value of each restricted stock grant is estimated on the date of grant using the closing price of the Company's Common Stock on The NASDAQ Global Market on the date of grant.

During the year ended December 31, 2015 and 2014, there were 137,780 and 204,209 shares of restricted stock granted, respectively. These restricted stock grants had a weighted average fair value (per share) at date of grant of $43.27 at December 31, 2015. At December 31, 2015 and 2014 there were 228,972 and 153,509 shares of unvested restricted stock outstanding, respectively. Compensation expense is determined for the issuance of restricted stock by amortizing on a straight-line basis over the requisite service period, or the vesting period, the aggregate fair value of the restricted stock awarded based on the closing price of the Company's common stock on the date of grant.

A summary of the Company's unvested restricted stock at December 31, 2015 and changes during the year ended December 31, 2015 is as follows:



	Restricted Stock		Weighted Average Grant Date Fair Value
Unvested at beginning of period	153,509		$	23.63
Granted	137,780		43.27
Vested	(54,517	)	22.94
Forfeited/cancelled	(7,800	)	43.65
Unvested restricted stock at end of period	228,972		$	34.94

As of December 31, 2015, the total remaining unrecognized compensation cost related to issuances of restricted stock was approximately $6.1 million and is expected to be recognized over a weighted-average period of 2.8 years. The grant date fair value of awards granted during the year ended December 31, 2015 was $6.0 million. The fair value of awards vested during the year ended December 31, 2015 was $2.3 million.

The Company does not have a formal policy regarding the source of shares issued upon exercise of stock options or issuance of restricted stock. NewLink expects shares issued to be issued from treasury shares or new shares.

On January 4, 2016, the Company approved grants of restricted stock unit awards to certain of the named executive officers for extraordinary performance in 2015. These are recognized as 2016 grants.

Income Taxes

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Income Taxes

Income tax expense consists of (in thousands):



	Current		Deferred		Total
Year Ended December 31, 2015:
U.S. federal	$	5,522	$	—	$	5,522
State and local	1,216		—		1,216
	$	6,738	$	—	$	6,738

Year Ended December 31, 2014:
U.S. federal	$	14,592	$	—	$	14,592
State and local	7,024		—		7,024
	$	21,616	$	—	$	21,616

Year Ended December 31, 2013:
U.S. federal	$	130	$	—	$	130
State and local	—		—		—
	$	130	$	—	$	130

The tax effects of temporary differences that give rise to significant portions of deferred tax assets and the deferred tax liability at December 31, 2015 and 2014 are presented below (in thousands):



	Year Ended December 31,
	2015			2014
Deferred tax assets:
Net operating loss carryforwards	$	654		$	1,042
Federal research and development tax credits	10,928			6,550
Share-based compensation	8,327			5,191
Deferred rent	519			550
Minimum tax credits	143			143
Accrued compensation	363			1,041
Unearned revenue	540			—
Accrued expenses	—			62
Leasehold improvements and equipment	26			—
Gross deferred tax assets	21,500			14,579
Less valuation allowance	(20,691		)	(14,552		)
Net deferred tax assets	809			27
Deferred tax liability:
Leasehold improvements and equipment	(809		)	(27		)
Total net deferred tax assets	$	—		$	—

The valuation allowance for deferred tax assets as of December 31, 2015 and 2014 was $20.7 million and $14.6 million, respectively. The net change in the total valuation allowance for the years ended December 31, 2015 and 2014 was an increase of $6.1 million and a decrease of $10.6 million, respectively. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected taxable income, and tax planning strategies in making this assessment. Valuation allowances have been established for the entire amount of the net deferred tax assets as of December 31, 2015 and 2014, due to the uncertainty of future recoverability.

Federal operating loss carryforwards as of December 31, 2015 of approximately $1.4 million and federal research credit carryforwards of approximately $10.9 million expire at various dates from 2026 through 2035. Sections 382 and 383 of the Internal Revenue Code limit a corporation’s ability to utilize its net operating loss carryforwards and certain other tax attributes (including research credits) to offset any future taxable income or tax if the corporation experiences a cumulative ownership change of more than 50% over any rolling three year period. State net operating loss carryforwards (and certain other tax attributes) may be similarly limited. An ownership change can therefore result in significantly greater tax liabilities than a corporation would incur in the absence of such a change and any increased liabilities could adversely affect the corporation’s business, results of operations, financial condition and cash flow.

Based on analysis from its inception through December 31, 2014, NewLink experienced Section 382 ownership changes in September 2001 and March 2003 and BPS experienced Section 382 ownership changes in January 2006 and January 2011 and the reported deferred tax assets reflect these expected limitations. These ownership changes limited NewLink's ability to utilize federal net operating loss carryforwards (and certain other tax attributes) that accrued prior to the respective ownership changes of NewLink and our subsidiary. Additional ownership changes may occur in the future as a result of events over which the Company will have little or no control, including purchases and sales of the Company’s equity by our 5% stockholders, the emergence of new 5% stockholders, additional equity offerings or redemptions of the Company’s stock or certain changes in the ownership of any of the Company’s 5% stockholders.

Income tax expense was $6.7 million, $21.6 million, and $130,000 for the years ended December 31, 2015, 2014 and 2013.

A reconciliation of income taxes at the statutory federal income tax rate to net income tax expense (benefit) included in the accompanying statements of operations is set forth in the following table:



	Year ended December 31,
	2015		2014		2013
U.S. federal income tax expense/(benefit) at the statutory rate	(35.0	)%	35.0	%	(35.0	)%
Available research and experimentation tax credits	(2.3	)	(7.0	)	—
State income taxes, net of federal taxes	(0.5	)	4.7		—
Loss in foreign subsidiary	43.6		8.4		—
Valuation allowance	13.7		(21.6	)	38.3
Other	0.5		(1.1	)	(2.9	)
Total	20.0	%	18.4	%	0.4	%

The loss in foreign subsidiary reconciling item in the above table is the tax effect of intercompany research and development expenses which are not deductible on the Company's consolidated federal income tax return.

Earnings Per Share (EPS)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Net Loss per Common Share

Earning Per Share (EPS)

The following table presents the calculations of earnings (loss) per share:



	Years Ended December 31,
	2015			2014		2013
Historical net income (loss) per share
Numerator
Net (loss) income attributable to common stockholders	$	(40,381	)	$	96,017	$	(31,180	)

Denominator
Basic weighted-average shares outstanding	28,586,585			27,838,873		25,275,179
Dilutive effect of stock option and restricted stock shares	—			3,186,226		—
Diluted weighted-average shares outstanding	28,586,585			31,025,099		25,275,179

Basic earnings (loss) per share	$	(1.41	)	$	3.45	$	(1.23	)
Diluted earnings (loss) per share	$	(1.41	)	$	3.09	$	(1.23	)

For December 31, 2015, potentially dilutive stock options to purchase 1,091,492 shares of common stock had exercise prices that were greater than the average market price were excluded from our calculation of diluted net income per share because to do so would be anti-dilutive. For December 31, 2014, and 2013, respectively, potentially dilutive common stock options of 5,098,311, and 4,486,564 were not included in the calculation of diluted net loss per common share because to do so would be anti-dilutive.

Licensing and Collaboration Agreements

12 Months Ended

Dec. 31, 2015

Licensing Agreements [Abstract]

Licensing Agreements

The Company is a party to a number of licensing agreements with respect to certain of the technologies that underlie its intellectual property. These agreements typically provide that the Company has exclusive rights to the use and sublicensing of the technologies in question for the duration of the intellectual property patent protection in question, subject to the Company meeting its financial and other contractual obligations under the agreements. The Company recognizes expense under its licensing agreements in the period the obligation is incurred. These agreements typically provide for a license fee based on a percent of sales and annual minimum royalties. For additional information regarding how the Company records payments under these agreements, see Note 2(j) above. The Company has incurred expense of approximately $2.0 million, $3.1 million, and $88,000, under all of the in-licensing agreements for the years ended December 31, 2015, 2014, and 2013, respectively, which is recorded as a component of general and administrative expenses.

Under certain license agreements the Company is obligated to make potential milestone payments as listed in the following table. In addition to the milestone payments, each license is paid as a low single-digit percentage of net sales of the licensed product, subject to annual minimum royalties. These obligations are contingent upon achieving the applicable milestone event, the timing of which cannot presently be determined. The milestone payments and royalty payments are in place through at least the expiration of certain of the Company's patents, which is currently 2029 and beyond.



Licensor		Aggregate potential milestone payments
Lankenau Institute for Medical Research under the IDO-1 Agreement		$1.36 million per licensed product

Lankenau Institute for Medical Research under the LIMR IDO-2 Agreement		$1.52 million per licensed product, subject to reductions if milestones also qualify under the IDO-1 Agreement

Lankenau Institute for Medical Research under the 2009 LIMR Agreement		$610,000 per licensed product, subject to reductions if milestones also qualify under the IDO-1 Agreement or LIMR IDO-2 Agreement

Augusta University Research Institute		$2.8 million per licensed product

Public Health Agency of Canada		C$205,000 per licensed product

The Ohio State University		$2.75 million for first licensed product

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2015
Employee Benefit Plans [Abstract]
Employee Benefit Plans	Employee Benefit Plans The Company sponsors a 401(k) plan, which includes a defined contribution feature. The Company's defined contribution was $361,000, $303,000, $198,000 for the years ended December 31, 2015, 2014 and 2013, respectively. The Company made discretionary contributions to the plan of $319,000, $299,000, and $144,000 for the years ended December 31, 2015, 2014 and 2013, respectively. The Company has approved employment agreements for certain executives, dated October 29, 2010, as amended January 4, 2016, that provide for the payment of 6 to 24 months of base salary, bonus, and group health insurance premiums plus accrued obligations upon termination of the executive in certain circumstances. The agreements include provisions to accelerate the vesting of stock options subject to certain events including those related to a change in control. The Company entered into the January 2016 amendments to the foregoing agreements, upon recommendation by the Compensation Committee of the Board of Directors, to align the terms of certain termination benefits with termination terms for executive officers at similarly situated companies to the Company.

Quarterly Financial Information (Unaudited)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information (Unaudited) [Abstract]

Quarterly Financial Information

Quarterly Financial Information (Unaudited)



	First			Second			Third			Fourth
	(In thousands, except per share data)

Year Ended December 31, 2015
Grant and licensing revenue	$	39,195		$	7,445		$	14,209		$	7,652
Income (loss) from operations	12,848			(15,942		)	(15,683		)	(14,825		)
Net income (loss)	11,190			(14,091		)	(15,906		)	(21,574		)
Basic earnings (loss) per share	0.40			$	(0.49	)	$	(0.55	)	$	(0.75	)
Diluted earnings (loss) per share	$	0.35		$	(0.49	)	$	(0.55	)	$	(0.75	)

Year Ended December 31, 2014
Grant and licensing revenue	$	334		$	212		$	2,801		$	169,245
Income (loss) from operations	(9,304		)	(9,127		)	(13,026		)	149,030
Net income (loss) (1)	(9,236		)	(9,163		)	(5,598		)	120,014
Basic earnings (loss) per share (1) (2)	(0.33		)	(0.33		)	(0.20		)	4.29
Diluted earnings (loss) per share (1) (2)	$	(0.33	)	$	(0.33	)	$	(0.20	)	$	3.83


(1)	During the third quarter of 2015, the Company corrected an immaterial error in the Company's 2014 income tax provision expense resulting in an increase to the Company's income tax expense and a decrease in net income of $6.8 million and a reduction of basic and diluted earnings per share for the three-month period ended December 31, 2014 of $0.25 and $0.22.

(2)

The Company identified an error relating to the basic and diluted loss per share amounts reported in Quarterly Financial Information Note to the Annual Report on Form 10-K for the year ended December 31, 2014 of $0.33 and $0.66 for the three-month periods ended June 30, 2014 and September 30, 2014, respectively. Management evaluated the impact of the error on the previously reported consolidated financial statements and notes and concluded the impact was not material. The Company has revised the per share amounts reported above to correctly report the quarter-to-date basic and diluted loss per share for these periods.

Significant Accounting Policies (Policies)	12 Months Ended
Significant Accounting Policies (Policies)	Dec. 31, 2015
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. generally accepted accounting principles, or U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the financial statements of NewLink and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.
Immaterial Error Correction	Immaterial Error Correction During the third quarter of 2015, we identified an immaterial error in the Company's 2014 income tax provision expense. Included in the consolidated balance sheet as of December 31, 2014 and the consolidated statement of operations and statement of cash flows for the year ending December 31, 2014 is an immaterial error correction related to the provision for income taxes. The income tax receivable as of December 31, 2014 has been decreased by $6.8 million and the income tax expense has been increased by $6.8 million. Due to this error, the Company’s net income and stockholders’ equity were both correspondingly overstated for the year ending December 31, 2014 by $6.8 million. The impact to basic and diluted earnings per share was a decrease of $0.25 and $0.22, respectively, for the year ending December 31, 2014. There was no impact to the net cash provided by operating activities in the consolidated statement of cash flows for the year ending December 31, 2014. The immaterial error correction also resulted in an increase in the Company's deferred tax asset and a corresponding increase to the valuation allowance as there is a full valuation allowance against net deferred tax assets due to the uncertainty of future recoverability. Management concluded that correcting the error would be immaterial to the fourth quarter results for 2014 and had no effect on the trend of financial results. Management also evaluated the impact of this error on our assessment of the effectiveness of internal control over financial reporting and concluded that our evaluation of controls as of December 31, 2014 remains effective.
Cash and Cash Equivalents	Cash and Cash Equivalents For the purposes of the consolidated statements of cash flows, the Company considers all highly liquid debt instruments with an original maturity of three months or less to be cash equivalents. Cash and cash equivalents of $195.6 million and $190.4 million at December 31, 2015 and 2014, respectively, consist of checking accounts, money market accounts and treasury bills.
Certificates of Deposit	Certificates of Deposit Certificates of deposit have original maturities of greater than three months. Certificates of deposit are classified as held-to-maturity with due dates through 2016 and are presented at amortized cost, which approximates fair value.
Leasehold Improvements and Equipment, and Deferred Rent	Leasehold Improvements and Equipment, and Deferred Rent Leasehold improvements and equipment are capitalized as the Company believes they have alternative future uses and are stated at cost. Equipment under capital leases is stated at the present value of minimum lease payments. Depreciation on all leasehold improvements and equipment is calculated on the straight-line method over the shorter of the lease term or estimated useful life of the asset. Computer equipment has useful lives of three to five years, lab equipment has a useful life of five years and contract manufacturing organization equipment has a useful life of five years. Deferred rent reflects improvement allowances from the Company's lessors deferred to be recognized as part of lease expense over the remaining term of the lease, which is recognized on a straight-line basis. Total deferred rents were $1.2 million and $1.3 million as of December 31, 2015 and 2014, respectively.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets Long-lived assets are reviewed for impairment whenever changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset group to future net undiscounted cash flows expected to be generated by the asset group, primarily relating to proceeds for selling the assets. If such assets are considered to be impaired, the impairment to be recognized is measured at the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell.
Revenue Recognition	Revenue Recognition The Company recognizes revenue for the performance of services or the shipment of products when each of the following four criteria is met: (1) persuasive evidence of an arrangement exists; (2) products are delivered or as services are rendered; (3) the sales price is fixed or determinable; and (4) collectability is reasonably assured. The Company follows ASC 605-25, Revenue Recognition - Multiple-Element Arrangements and ASC 808, Collaborative Arrangements , if applicable, to determine the recognition of revenue under our license and collaborative research, development and commercialization agreements. The terms of these agreements generally contain multiple elements, or deliverables, which may include (1) licenses to our intellectual property, (2) materials and technology, (3) clinical supply, and/or (4) participation on joint research or joint steering committees. The payments we may receive under these arrangements typically include one or more of the following: non-refundable, up-front license fees; funding of research and/or development efforts; amounts due upon the achievement of specified milestones; and/or royalties on future product sales. ASC 605-25 provides guidance relating to the separability of deliverables included in an arrangement into different units of accounting and the allocation of arrangement consideration to the units of accounting. The evaluation of multiple-element arrangements requires management to make judgments about (1) the identification of deliverables, (2) whether such deliverables are separable from the other aspects of the contractual relationship, (3) the estimated selling price of each deliverable, and (4) the expected period of performance for each deliverable. To determine the units of accounting under a multiple-element arrangement, management evaluates certain separation criteria, including whether the deliverables have stand-alone value, based on the relevant facts and circumstances for each arrangement. Management then estimates the selling price for each unit of accounting and allocates the arrangement consideration to each unit utilizing the relative selling price method. The allocated consideration for each unit of accounting is recognized over the related obligation period in accordance with the applicable revenue recognition criteria. If there are deliverables in an arrangement that are not separable from other aspects of the contractual relationship, they are treated as a combined unit of accounting, with the allocated revenue for the combined unit recognized in a manner consistent with the revenue recognition applicable to the final deliverable in the combined unit. Payments received prior to satisfying the relevant revenue recognition criteria are recorded as unearned revenue in the accompanying balance sheets and recognized as revenue when the related revenue recognition criteria are met. The Company typically receives non-refundable, up-front payments when licensing our intellectual property, which often occurs in conjunction with a research and development agreement. If management believes that the license to our intellectual property has stand-alone value, the Company generally recognizes revenue attributed to the license upon delivery provided that there are no future performance requirements for use of the license. When management believes that the license to our intellectual property does not have stand-alone value, the Company would recognize revenue attributed to the license on a straight-line basis over the contractual or estimated performance period. When the performance period is not specifically identifiable from the agreement, the Company would estimate the performance period based upon provisions contained within the agreement, such as the duration of the research or development term. For payments payable on achievement of milestones that do not meet all of the conditions to be considered substantive, the Company recognizes a portion of the payment as revenue when the specific milestone is achieved, and the contingency is removed. Other contingent event-based payments for which payment is either contingent solely upon the passage of time or the result of collaborator's performance are recognized when earned. The Company receives payments from government entities under its grants and contracts with the National Institute of Health, the Department of Defense, and the United States Department of Health and Human Services. These agreements provide the Company cost reimbursement plus a percentage for certain types of expenditures in return for research and development activities over a contractually defined period. Grant revenues are recognized in the period during which the related costs are incurred, provided that the conditions under which the costs submitted or to be submitted for reimbursement have been met and the Company has only perfunctory obligations outstanding. During the years ended December 31, 2015, 2014, and 2013, the Company has earned $32.4 million, $6.6 million, and $1.1 million in grant revenue, respectively. We had $4.1 million and $3.7 million of receivables from the government contracts recorded in other receivables and $3.6 million and $7.5 million of unbilled expenses relating to the government contracts recorded in prepaid expenses and other assets on the balance sheet for the years ended December 31, 2015 and 2014, respectively.
Expenses Accrued Under Contractual Arrangements with Third Parties; Accrued Clinical Expenses	Expenses Accrued Under Contractual Arrangements with Third Parties; Accrued Clinical Expenses The Company estimates its accrued expenses through a process of reviewing open contracts and purchase orders, communicating with personnel to identify services that have been performed and estimating the level of service performed and the associated cost incurred for the service that may not be invoiced from the provider. The estimates of accrued expenses as of each balance sheet date are based on facts and circumstances known at that time. Such estimates are periodically confirmed with the service providers to verify accuracy. The Company bases its expenses related to clinical trials on estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and contract research organizations that conduct and manage clinical trials on behalf of the Company. Invoicing from third-party contractors for services performed can lag several months. The Company accrues the costs of services rendered in connection with third-party contractor activities based on its estimate of management fees, site management and monitoring costs and data management costs as contracted. Differences between actual clinical trial costs and estimated clinical trial costs are adjusted for in the period in which they become known through operations.
Research and Development	Research and Development Research and development costs are expensed as incurred. Certain research and development expenses are refundable from the state of Iowa without regard to income. State research and development credits of $450,000 and $748,000 at December 31, 2015 and 2014, respectively, are reflected as a reduction in income taxes on the accompanying consolidated statements of operations. State research and development credits of $329,000 at December 31, 2013, are reflected as a reduction of research and development expenses on the accompanying consolidated statements of operations.
Patents	Patents The Company generally applies for patent protection on processes and products. Patent application costs are expensed as incurred as a component of general and administrative expense, as recoverability of such expenditures is uncertain.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operating results in the period that includes the enactment date. Management assesses the realizability of deferred tax assets and records a valuation allowance if it is more likely than not that all or a portion of the deferred tax assets will not be realized. Income tax expense was 20.0% of loss before income taxes in 2015. A valuation allowance of $20.7 million as of December 31, 2015 offsets our net deferred tax assets. The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. As of December 31, 2015 and 2014, the Company has not recognized any uncertain tax positions.
Share-Based Compensation	Share-Based Compensation The Company is required to estimate the grant-date fair value of stock options, stock awards and restricted stock issued to employees and recognize this cost over the period these awards vest. The Company estimates the fair value of each award granted using the Black-Scholes option pricing model. The Black-Scholes model requires the input of assumptions, including the expected stock price volatility, the calculation of expected term and the fair value of the underlying common stock on the date of grant, among other inputs. Generally, the Company has issued employee awards that vest over time. For these awards, the Company records compensation cost on a straight-line basis over the vesting period. The Company issues awards, which typically vest 20% to 25% on the first anniversary date of issuance with the remaining options vesting ratably over the next 36 to 48 months, as determined by the Board of Directors at the time of grant. The Company calculates the fair value of the award on the grant date, which is the date the award is authorized by the Board of Directors or Chief Executive Officer and the employee has an understanding of the terms of the award. The Company has issued awards to nonemployee consultants and advisers. All grants to nonemployees are valued using the same fair value method that we use for grants to employees. The compensation cost on these awards is measured each period until vesting, and is recognized through the earlier of the vesting of the award or completion of services by the nonemployee. Following is a description of the inputs for the Black-Scholes model: Exercise Price The Company’s stock options granted prior to the IPO were granted with an exercise price as determined by the NewLink Board of Directors in good faith with the assistance of a third-party appraisal report and an evaluation of milestones achieved. Subsequent to the IPO, the Company uses the quoted market price as listed on the public exchange on the date of grant. If Incentive Stock Options are granted to a 10% stockholder in the Company, the exercise price shall not be less than 110% of the common stock’s fair market value on the date of grant. Expected Term (in Years) The expected term of a stock option is the period of time for which the option is expected to be outstanding. The Company uses historical exercise and option expiration data to estimate the expected term for the Black-Scholes grant-date valuation. Risk-Free Interest Rate The Company uses the average yield on current U.S. Treasury instruments with terms that approximate the expected term of the stock options being valued. Expected Dividend Yield The expected dividend yield for all of the Company’s stock option grants is 0%, as the Company has not declared a cash dividend since inception and has no plans to declare a dividend. Expected Volatility The Company estimates future expected volatility for each stock option valuation utilizing volatility rates of similar publicly traded companies considered to be in the same peer group. Prior to 2015, the Company used a combination of its own data and peer group data to compute our volatility. Beginning in 2015, the Company began to use its historical stock price volatility. The volatility is calculated over a period of time commensurate with the expected term for the options granted. Forfeitures The share-based compensation expense has been reduced for estimated forfeitures. The estimated forfeiture rate is based on historical experience of the Company’s option plan, which the Company expects to continue at the current level, and any adjustments in the forfeiture rate in the future will result in a cumulative adjustment in the period that this estimate is changed. Ultimately, the total compensation expense recognized for any given stock-based award over its vesting period will only be for those shares that actually vest.
Segments	Segments The Company operates in one segment. The Company conducts research and development activities based from facilities located in Ames, Iowa. NewLink and BPS have corporate headquarters in Ames, Iowa and Austin, Texas. The Company conducts preclinical and clinical research in the biopharmaceutical industry. The chief operating decision maker uses cash flow as the primary measure to manage the business and management does not segment its business for internal reporting or decision-making.
Financial Instruments	Financial Instruments and Concentrations of Credit Risk The fair values of cash and cash equivalents, certificates of deposit, receivables and accounts payable, which are recorded at cost, approximate fair value based on the short-term nature of these financial instruments. The fair value of notes payable and capital lease obligations was $941,000 and $1.1 million as of December 31, 2015 and 2014, respectively, and was determined using Level 2 inputs. The Company is unable to estimate the fair value of the royalty obligation based on future product sales as the timing of payments, if any, is uncertain.
Concentration of Revenue	Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, and certificates of deposit. Cash and cash equivalents are held by financial institutions and are federally insured up to certain limits. At times, the Company’s cash and cash equivalents balance exceeds the federally insured limits. To limit the credit risk, the Company invests its excess cash primarily in high quality securities such as money market funds.
Earnings Per Share	Earnings per share (EPS) The Company computes basic EPS attributable to the Company's common stockholders by dividing net income (loss) attributable to the Company by our weighted-average common shares outstanding, during the period. Diluted EPS reflects the potential dilution beyond shares for basic EPS that could occur if securities or other contracts to issue common stock were exercised, converted into common stock, or resulted in the issuance of common stock that would have shared in our earnings. The Company computes basic and diluted EPS using net income (loss) attributable to the Company's common stockholders, and its actual weighted-average shares.
Concentration of Revenue	Concentration of Revenue Prior to 2014, the Company's revenue was primarily obtained from government research grants. Genentech and Merck accounted for 21.5% and 31.3%, respectively, of the $68.5 million of revenue for the year ended December 31, 2015. Genentech, a member of the Roche Group and Merck Sharpe and Dohme Corp., or Merck, accounted for 78.9% and 17.2%, respectively, of the $172.6 million of revenue earned for the year ended December 31, 2014, with the remainder obtained from government grants.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In November 2015, the Financial Accounting Standards Board, or FASB, issued FASB Accounting Standards Update (ASU) No. 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes. The amendments in this update require that deferred tax liabilities and assets be classified as noncurrent in a classified statement of financial position. This ASU is effective for financial statements issued for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Earlier application is permitted as of the beginning of an interim or annual reporting period. The Company early adopted this ASU on a prospective basis in the fourth quarter of fiscal 2015. Prior periods were not retrospectively adjusted. As of December 31, 2015 and 2014, all deferred taxes were fully offset by a valuation allowance, therefore adoption of this guidance did not have an impact on the presentation of our consolidated financial statements. On May 28, 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2018; however, early adoption at January 1, 2017, is permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected a transition method, nor has it determined the effect of the standard on its ongoing financial reporting.

Leases (Tables)

12 Months Ended

Dec. 31, 2015

Leases [Abstract]

Capital Leased Assets

The following is an analysis of the leased property under capital leases by major class (in thousands):



	Asset balances at December 31,
Class of property	2015			2014
Lab equipment	$	489		$	489
Leasehold improvements	27			27
Computer equipment	54			54
Total property under capital leases	570			570
Less accumulated depreciation and amortization	(472		)	(384		)
Capital leased assets, net	$	98		$	186

Minimum Lease Payments for Capital Leases



Year ending December 31:
2016	$	13
2017	—
Total minimum lease payments	13
Less amount representing interest	(1		)
Present value of net minimum lease payments	$	12

Minimum Rental Payments for Operating Leases

Future minimum lease payments under the noncancelable operating leases (with initial or remaining lease terms in excess of one year) as of December 31, 2015 are as follows (in thousands):



Year ending December 31:
2016	$	1,417
2017	991
2018	509
2019	452
2020	38
Thereafter	—
Total	$	3,407

Common Stock Equity Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2015

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

Stock Option Activity

The following table summarizes the stock option activity for the year ended December 31, 2015:



	Number of options		Weighted average exercise price		Weighted average remaining contractual term (years)
Outstanding at beginning of period	5,098,311		$	9.46
Options granted	1,019,445		42.57
Options exercised	(422,767	)	7.94
Options forfeited	(48,403	)	36.70
Options expired	(106	)	14.19
Outstanding at end of period	5,646,480		$	15.11	6.0
Options exercisable at end of period	4,039,770		$	8.04	4.9

Assumptions Used in Black-Scholes Pricing Model for New Grants



	Years Ended December 31,
	2015	2014	2013
Number of options granted	1,019,445	974,555	860,250
Risk-free interest rate	1.51%-2.00%	1.73%-2.24%	.89%-2.14%
Expected dividend yield	—	—	—
Expected volatility	62.5%-67.3%	57.4%-68.3%	61.4%-67.3%
Expected term (in years)	5.9-7.0	6.0-7.0	4.8-7.0
Weighted average grant-date fair value per share	$26.36	$14.80	$7.50

Other share-based compensation activity

The following table summarizes the intrinsic value of options exercised and the fair value of awards vested during the years ended December 31, 2015, 2014 and 2013:

Restricted Stock Activity

A summary of the Company's unvested restricted stock at December 31, 2015 and changes during the year ended December 31, 2015 is as follows:



	Restricted Stock		Weighted Average Grant Date Fair Value
Unvested at beginning of period	153,509		$	23.63
Granted	137,780		43.27
Vested	(54,517	)	22.94
Forfeited/cancelled	(7,800	)	43.65
Unvested restricted stock at end of period	228,972		$	34.94

Income Taxes Income Tax Expense (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Income tax expense

Income tax expense consists of (in thousands):



	Current		Deferred		Total
Year Ended December 31, 2015:
U.S. federal	$	5,522	$	—	$	5,522
State and local	1,216		—		1,216
	$	6,738	$	—	$	6,738

Year Ended December 31, 2014:
U.S. federal	$	14,592	$	—	$	14,592
State and local	7,024		—		7,024
	$	21,616	$	—	$	21,616

Year Ended December 31, 2013:
U.S. federal	$	130	$	—	$	130
State and local	—		—		—
	$	130	$	—	$	130

Income Taxes Deferred Tax Assets (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Valuation Allowance

The tax effects of temporary differences that give rise to significant portions of deferred tax assets and the deferred tax liability at December 31, 2015 and 2014 are presented below (in thousands):



	Year Ended December 31,
	2015			2014
Deferred tax assets:
Net operating loss carryforwards	$	654		$	1,042
Federal research and development tax credits	10,928			6,550
Share-based compensation	8,327			5,191
Deferred rent	519			550
Minimum tax credits	143			143
Accrued compensation	363			1,041
Unearned revenue	540			—
Accrued expenses	—			62
Leasehold improvements and equipment	26			—
Gross deferred tax assets	21,500			14,579
Less valuation allowance	(20,691		)	(14,552		)
Net deferred tax assets	809			27
Deferred tax liability:
Leasehold improvements and equipment	(809		)	(27		)
Total net deferred tax assets	$	—		$	—

Income Taxes Income Tax Rate Reconciliation (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Income Tax Rate Reconciliation



	Year ended December 31,
	2015		2014		2013
U.S. federal income tax expense/(benefit) at the statutory rate	(35.0	)%	35.0	%	(35.0	)%
Available research and experimentation tax credits	(2.3	)	(7.0	)	—
State income taxes, net of federal taxes	(0.5	)	4.7		—
Loss in foreign subsidiary	43.6		8.4		—
Valuation allowance	13.7		(21.6	)	38.3
Other	0.5		(1.1	)	(2.9	)
Total	20.0	%	18.4	%	0.4	%

Net Loss per Common Share (Tables)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Basic and Diluted Net Loss per Common Share

The following table presents the calculations of earnings (loss) per share:



	Years Ended December 31,
	2015			2014		2013
Historical net income (loss) per share
Numerator
Net (loss) income attributable to common stockholders	$	(40,381	)	$	96,017	$	(31,180	)

Denominator
Basic weighted-average shares outstanding	28,586,585			27,838,873		25,275,179
Dilutive effect of stock option and restricted stock shares	—			3,186,226		—
Diluted weighted-average shares outstanding	28,586,585			31,025,099		25,275,179

Basic earnings (loss) per share	$	(1.41	)	$	3.45	$	(1.23	)
Diluted earnings (loss) per share	$	(1.41	)	$	3.09	$	(1.23	)

Licensing and Collaboration Agreements (Tables)

12 Months Ended

Dec. 31, 2015

Licensing Agreements [Abstract]

Licensing Agreements



Licensor		Aggregate potential milestone payments
Lankenau Institute for Medical Research under the IDO-1 Agreement		$1.36 million per licensed product

Lankenau Institute for Medical Research under the LIMR IDO-2 Agreement		$1.52 million per licensed product, subject to reductions if milestones also qualify under the IDO-1 Agreement

Lankenau Institute for Medical Research under the 2009 LIMR Agreement		$610,000 per licensed product, subject to reductions if milestones also qualify under the IDO-1 Agreement or LIMR IDO-2 Agreement

Augusta University Research Institute		$2.8 million per licensed product

Public Health Agency of Canada		C$205,000 per licensed product

The Ohio State University		$2.75 million for first licensed product

Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information (Unaudited) [Abstract]

Quarterly Financial Information (Unaudited)



	First			Second			Third			Fourth
	(In thousands, except per share data)

Year Ended December 31, 2015
Grant and licensing revenue	$	39,195		$	7,445		$	14,209		$	7,652
Income (loss) from operations	12,848			(15,942		)	(15,683		)	(14,825		)
Net income (loss)	11,190			(14,091		)	(15,906		)	(21,574		)
Basic earnings (loss) per share	0.40			$	(0.49	)	$	(0.55	)	$	(0.75	)
Diluted earnings (loss) per share	$	0.35		$	(0.49	)	$	(0.55	)	$	(0.75	)

Year Ended December 31, 2014
Grant and licensing revenue	$	334		$	212		$	2,801		$	169,245
Income (loss) from operations	(9,304		)	(9,127		)	(13,026		)	149,030
Net income (loss) (1)	(9,236		)	(9,163		)	(5,598		)	120,014
Basic earnings (loss) per share (1) (2)	(0.33		)	(0.33		)	(0.20		)	4.29
Diluted earnings (loss) per share (1) (2)	$	(0.33	)	$	(0.33	)	$	(0.20	)	$	3.83


(1)	During the third quarter of 2015, the Company corrected an immaterial error in the Company's 2014 income tax provision expense resulting in an increase to the Company's income tax expense and a decrease in net income of $6.8 million and a reduction of basic and diluted earnings per share for the three-month period ended December 31, 2014 of $0.25 and $0.22.

(2)

Description of Business Activities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Feb. 04, 2013	Nov. 16, 2011
Summary of Financings
Genentech Upfront Payments	$ 150.0
Merck Upfront Payments	30.0
Merck One-Time Milestones	20.0
Initial Public Offering
Summary of Financings
FInancing proceeds			$ 37.6
Follow-on Offering
Summary of Financings
FInancing proceeds		$ 49.0
ATM Offering
Summary of Financings
FInancing proceeds	$ 58.7

Significant Accounting Policies (Details) - USD ($)	3 Months Ended								12 Months Ended
Significant Accounting Policies (Details) - USD ($)	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment									$ 6,800,000
Impact of Immaterial Error Correction on Earnings Per Share, Basic										$ 0.25
Impact of Immaterial Error Correction on Earnings Per Share, Diluted										$ 0.22
Financial Instruments
Fair value and carrying value of notes payable and capital lease obligations	$ 941,000				$ 1,100,000				941,000	$ 1,100,000
Cash and Cash Equivalents
Cash and cash equivalents	195,620,000				190,404,000				195,620,000	190,404,000
Leasehold Improvements and Equipment
Deferred rents	1,200,000				1,300,000				1,200,000	1,300,000
Revenue Recognition
Net (loss) income	(21,574,000)	$ (15,906,000)	$ (14,091,000)	$ 11,190,000	120,014,000	$ (5,598,000)	$ (9,163,000)	$ (9,236,000)	(40,381,000)	96,017,000	$ (31,180,000)
Grant revenue									32,358,000	6,642,000	1,093,000
Accrued Fees and Other Revenue Receivable	4,100,000				3,700,000				4,100,000	3,700,000
Unbilled Contracts Receivable	3,600,000				7,500,000				3,600,000	7,500,000
Licensing Agreements
Total operating revenues	7,652,000	$ 14,209,000	$ 7,445,000	$ 39,195,000	169,245,000	$ 2,801,000	$ 212,000	$ 334,000	68,501,000	172,592,000	1,093,000
Research and Development
Iowa refundable research credit									$ 450,000	$ 748,000	$ 329,000
Stock Option Valuation
ISO Stockholder Ownership Threshold									10.00%
Greater Than 10% Stockholder ISO Exercise Price Threshold									110.00%
Expected Dividend Yield									0.00%
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Percent									20.00%	18.40%	0.40%
Deferred Tax Assets, Valuation Allowance	$ 20,691,000				$ 14,552,000				$ 20,691,000	$ 14,552,000
Customer Concentration Risk [Member] \| Genentech [Member]
Licensing Agreements
Concentration Risk, Percentage									21.50%	78.90%
Customer Concentration Risk [Member] \| Merck [Member]
Licensing Agreements
Concentration Risk, Percentage									31.30%	17.20%

Leases (Details) - USD ($)	12 Months Ended
Leases (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Capital Leases, Lessee Balance Sheet [Abstract]
Lab equipment	$ 489,000	$ 489,000
Leasehold improvements	27,000	27,000
Computer equipment	54,000	54,000
Total property under capital leases	570,000	570,000
Less accumulated depreciation and amortization	(472,000)	(384,000)
Capital leased assets, net	98,000	186,000
Capital Leases, Future Minimum Payments, Net Minimum Payments, Rolling Maturity [Abstract]
Capital Leases, Due in 2015	13,000
Capital Leases, Due in 2016	0
Capital Leases, Minimum Payments Due	13,000
Capital Leases, Interest Included in Payments	1,000
Capital Leases, Minimum Payments, Present Value	12,000
Operating Leases, Rent Expense, Net	1,700,000	$ 1,200,000	$ 766,000
Operating Leases, Future Minimum Payments Receivable [Abstract]
Operating Leases, Due in 2015	1,417,000
Operating Leases, Due in 2016	991,000
Operating Leases, Due in 2017	509,000
Operating Leases, Due in 2018	452,000
Operating Leases, Due in 2019	38,000
Operating Leases, Due Thereafter	0
Operating Leases, Future Minimum Payments Due	$ 3,407,000

Long-Term Debt Conversion to Royalty Obligation (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Iowa Department of Economic Development Loan 2005 \| Amount
Debt Instrument
Original Balance		$ 6,000,000
Outstanding Balance			$ 6,000,000
Iowa Economic Development Authority Royalty Obligation 2012 \| Amount
Debt Instrument
Outstanding Balance	$ 6,000,000
Revised Royalty Maximum Amount	$ 6,800,000
Iowa Economic Development Authority Royalty Obligation 2012 \| Percent
Debt Instrument
Revised Royalty Rate	0.50%
Iowa State University Research Park Loan 2009 \| Amount
Debt Instrument
Original Balance	$ 800,000
Outstanding Balance	$ 246,000	348,000
Iowa State University Research Park Loan 2009 \| Percent
Debt Instrument
Interest rate initial	3.00%
Interest rate after five years	5.00%
Interest rate in default	8.00%
Iowa State University Research Park Loan 2012 \| Amount
Debt Instrument
Original Balance		456,000
Outstanding Balance	$ 284,000	$ 339,000
Iowa State University Research Park Loan 2012 \| Percent
Debt Instrument
Interest rate initial		3.00%
Interest rate after five years	5.00%
Interest rate in default	8.00%
City of Ames Forgivable Loan 2010 \| Amount
Debt Instrument
Original Available Balance	$ 400,000
Jobs by March 10, 2015	150
Lease square feet	20,000
Repayment per job	$ 3,100
Outstanding Balance Forgivable Loan	$ 397,000
City of Ames Forgivable Loan 2010 \| Percent
Debt Instrument
Interest rate in default	6.50%

License and Research Collaboration Agreements (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Deferred Revenue Arrangement [Line Items]
Genentech Upfront Payments	$ 150,000,000
Genentech Potential Milestones	1,000,000,000
Genentech Revenue Allocated to License and Manufacturing Technology Transfer Revenue Recognition	14,700,000	$ 136,200,000
Genentech Program Materials and Technology Transfer Revenue Recognition	9,400,000
Genentech Clinical Supply of GDC-0919 Product Revenue Recognition	2,500,000
Genentech Participation in JRC Revenue Recognition	151,000
Genentech Alliance Manager Revenue Recognition	502,000
Genentech Reimbursement NewLink Employees Revenue Recognition	2,100,000
Merck Upfront Payments	30,000,000
Merck One-Time Milestones	20,000,000
Merck Revenue Allocated to License	21,400,000	$ 29,600,000
Merck Revenue Allocated to Other Deliverables	170,000
Merck Reimbursement Ebola Costs Revenue Recognition	1,200,000
Merck [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue	232,000
Merck Deferred Revenue for Deliverables	53,800
Genentech [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue	13,800,000
Genentech Deferred Revenue for Deliverables	$ 1,200,000

Preferred Stock Preferred Stock Authorized (Details) - shares	Dec. 31, 2015	Dec. 31, 2014
Preferred Stock Authorized [Abstract]
Blank check preferred stock, authorized shares	5,000,000	5,000,000

Common Stock Equity Incentive Plans (Details)	12 Months Ended
Common Stock Equity Incentive Plans (Details)	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares	Dec. 31, 2012 shares	Dec. 31, 2011 shares
Common Stock Equity Incentive Plan
Increase in Number of Shares Authorized	1,152,565
Total Compensation Cost Related to Non-vested Option Awards \| $	$ 35,800,000
Weighted Average Vesting Period for Non-vested Option Awards, In Years	3
Share-based Compensation Expense \| $	$ 15,900,000	$ 8,600,000	$ 4,400,000
Income Tax Benefit from Compensation Expense \| $	7,800,000	3,700,000	0
Intrinsic Value of Options Exercised \| $	16,700,000	8,500,000	1,600,000
Fair Value of Options Vested \| $	9,600,000	7,500,000	$ 3,000,000
Fair Value of Awards Vested - Accelerated Compensation Cost \| $	$ 2,800,000	$ 1,700,000
Intrinsic Value Price per Share Base \| $ / shares	$ 36.39
Intrinsic Value Outstanding \| $	$ 126,200,000
Intrinsic Value Vested \| $	115,000,000
Intrinsic Value Unvested \| $	$ 11,200,000
Assumptions Used in Black Scholes Pricing Model for New Grants
Risk Free Interest Rate, Minimum	1.51%	1.73%	0.89%
Risk Free Interest Rate, Maximum	2.00%	2.24%	2.14%
Dividend Rate	0.00%	0.00%	0.00%
Volatility Rate, Minimum	62.50%	57.40%	61.40%
Volatility Rate, Maximum	67.30%	68.30%	67.30%
Weighted average grant-date fair value per share \| $ / shares	$ 26.36	$ 0	$ 0
Stock Option Activity
Outstanding at beginning of period	5,098,311
Outstanding at beginning of period, weighted average exercise price \| $ / shares	$ 9.46
Grants	1,019,445	974,555	860,250
Grants, weighted average exercise price \| $ / shares	$ 42.57
Exercises	(422,767)
Exercises, weighted average exercise price \| $ / shares	$ 7.94
Forfeitures	(48,403)
Forfeitures, weighted average exercise price \| $ / shares	$ 36.70
Expirations	(106)
Expirations, weighted average exercise price \| $ / shares	$ 14.19
Outstanding at end of period	5,646,480	5,098,311
Outstanding at end of period, weighted average exercise price \| $ / shares	$ 15.11	$ 9.46
Outstanding at end of period, weighted average remaining contractual term, in years	6.0
Exercisable	4,039,770
Exercisable, weighted average exercise price \| $ / shares	$ 8.04
Exercisable, weighted average remaining contractual term, in years	4.9
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested at beginning of period	153,509
Granted	137,780	204,209
Vested	(54,517)
Forfeited/cancelled	(7,800)
Unvested restricted stock at end of period	228,972	153,509
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Grants, weighted average grant date fair value \| $ / shares	$ 43.27
Vested, weighted average grant date fair value \| $ / shares	22.94
Forfeited/cancelled, weighted average grant date fair value \| $ / shares	43.65
End of period, weighted average grant date fair value \| $ / shares	$ 34.94
Total Compensation Cost Related to Non-vested Restricted Stock Awards \| $	$ 6,100,000
Weighted Average Vesting Period for Non-vested Restricted Stock Awards, In Years	2.8
Grant Date Fair Value of Restricted Stock Awards Granted \| $	$ 6,000,000
Fair Value of Restricted Stock Awards Vested \| $	$ 2,300,000
Minimum
Assumptions Used in Black Scholes Pricing Model for New Grants
Expected Term	5 years 10 months 24 days	6 years	4 years 9 months 18 days
Maximum
Assumptions Used in Black Scholes Pricing Model for New Grants
Expected Term	7 years	7 years	7 years
2009 Equity Incentive Plan
Common Stock Equity Incentive Plan
Number of Shares Authorized	7,919,109	6,799,854
Number of Shares Available for Grant	774,499	654,935
Increase in Number of Shares Authorized		1,119,255	1,066,340	838,375	714,286
Evergreen Increase Percentage	4.00%
2009 Equity Incentive Plan \| Minimum
Common Stock Equity Incentive Plan
First Year Vesting Percentage	20.00%
Remaining Vesting Period in Months	36
2009 Equity Incentive Plan \| Maximum
Common Stock Equity Incentive Plan
First Year Vesting Percentage	25.00%
Remaining Vesting Period in Months	48
2010 Employee Stock Purchase Plan
Common Stock Equity Incentive Plan
Number of Shares Authorized		214,285
Number of Shares Available for Grant	231,392
Increase in Number of Shares Authorized	185,715
Shares Issued	40,248	25,168
2010 Non-Employee Directors' Stock Option Plan
Common Stock Equity Incentive Plan
Number of Shares Authorized		238,095
Number of Shares Available for Grant	106,640
Increase in Number of Shares Authorized	161,905

Income Taxes Income Tax Expense (Details) - USD ($)	12 Months Ended
Income Taxes Income Tax Expense (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Current U.S. federal income tax expense	$ 5,522,000	$ 14,592,000	$ 130,000
Deferred U.S. federal income tax expense	0	0	0
Federal income tax expense	5,522,000	14,592,000	130,000
Current state and local income tax expense	1,216,000	7,024,000	0
Deferred state and local income tax expense	0	0	0
State and local income tax expense	1,216,000	7,024,000	0
Current income tax expense	6,738,000	21,616,000	130,000
Deferred income tax expense	0	0	0
Income tax expense	$ 6,738,000	$ 21,616,000	$ 130,000

Income Taxes Deferred Tax (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 654	$ 1,042
Federal research and development tax credits	10,928	6,550
Share-based compensation	8,327	5,191
Deferred rent	519	550
Minimum tax credits	143	143
Accrued compensation	363	1,041
Unearned revenue	540	0
Accrued expenses	0	62
Leasehold improvements and equipment	26	0
Gross deferred tax assets	21,500	14,579
Less valuation allowance	20,691	14,552
Net deferred tax assets	809	27
Leasehold improvements and equipment	(809)	(27)
Total net deferred tax assets	$ 0	$ 0

Income Taxes Other Tax Disclosures (Details) - USD ($)	12 Months Ended
Income Taxes Other Tax Disclosures (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Deferred Tax Valuation Allowance	$ (20,691,000)	$ (14,552,000)
Change in Deferred Tax Valuation Allowance	6,100,000	(10,600,000)
Federal Operating Loss Carryforwards	1,400,000
Federal Research Credit Carryforward	10,900,000
Income tax expense	$ 6,738,000	$ 21,616,000	$ 130,000

Income Taxes Income Tax Rate Reconciliation (Details)	12 Months Ended
Income Taxes Income Tax Rate Reconciliation (Details)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
U.S. federal income tax expense/(benefit) at the statutory rate	(35.00%)	35.00%	(35.00%)
Available research and experimentation tax credits	(2.30%)	(7.00%)	0.00%
State income taxes, net of federal taxes	(0.50%)	4.70%	0.00%
Loss in foreign subsidiary	43.60%	8.40%	0.00%
Valuation allowance	13.70%	(21.60%)	38.30%
Other	0.50%	(1.10%)	(2.90%)
Total	20.00%	18.40%	0.40%

Net Loss per Common Share (Net Loss Per Share Computation) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Net (loss) income attributable to common stockholders	$ (21,574)	$ (15,906)	$ (14,091)	$ 11,190	$ 120,014	$ (5,598)	$ (9,163)	$ (9,236)	$ (40,381)	$ 96,017	$ (31,180)
Basic weighted-average shares outstanding									28,586,585	27,838,873	25,275,179
Dilutive effect of stock option and restricted stock shares									0	3,186,226	0
Diluted weighted-average shares outstanding									28,586,585	31,025,099	25,275,179
Basic (loss) earnings per share	$ (0.75)	$ (0.55)	$ (0.49)	$ 0.40	$ 4.29	$ (0.20)	$ (0.33)	$ (0.33)	$ (1.41)	$ 3.45	$ (1.23)
Diluted earnings (loss) per share	$ (0.75)	$ (0.55)	$ (0.49)	$ 0.35	$ 3.83	$ (0.20)	$ (0.33)	$ (0.33)	$ (1.41)	$ 3.09	$ (1.23)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Net Loss per Common Share (Antidilutive Securities) (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share
Potentially dilutive securities excluded from computation of diluted net loss per share	1,091,492	5,098,311	4,486,564

Licensing and Collaboration Agreements (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2015 CAD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Licensing Agreements
Licensing Payments Under All In-Licensing Agreements	$ 2,000,000		$ 3,100,000	$ 88,000
Drexel University
Licensing Agreements
Potential Milestone Payment per Licensed Product	1,000,000
Lankenau Institute for Medical Research IDO-1
Licensing Agreements
Potential Milestone Payment per Licensed Product	1,360,000
Lankenau Institute for Medical Research IDO-2
Licensing Agreements
Potential Milestone Payment per Licensed Product	1,520,000
Lankenau Institute for Medical Research 2009 Agreement
Licensing Agreements
Potential Milestone Payment per Licensed Product	610,000
Georgia Regents Research Institute
Licensing Agreements
Potential Milestone Payment per Licensed Product	2,800,000
Public Health Agency of Canada
Licensing Agreements
Potential Milestone Payment per Licensed Product		$ 205
Ohio State University
Licensing Agreements
Potential Milestone Payment per Licensed Product	$ 2,750,000

Employee Benefit Plans (Details)	12 Months Ended
Employee Benefit Plans (Details)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Maximum
Base Salary Continutation Upon Termintation
Duration of Payment, Months	24
Minimum
Base Salary Continutation Upon Termintation
Duration of Payment, Months	6
Defined Contribution
Defined Contribution Pension Plan
Defined Contribution Plan	$ 361,000	$ 303,000	$ 198,000
Discretionary Contribution
Defined Contribution Pension Plan
Defined Contribution Plan	$ 319,000	$ 299,000	$ 144,000

Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment									$ 6,800
Impact of Immaterial Error Correction on Earnings Per Share, Basic										$ 0.25
Impact of Immaterial Error Correction on Earnings Per Share, Diluted										$ 0.22
Grant and licensing revenue	$ 7,652	$ 14,209	$ 7,445	$ 39,195	$ 169,245	$ 2,801	$ 212	$ 334	68,501	$ 172,592	$ 1,093
Income (Loss) from Continuing Operations Attributable to Parent	(14,825)	(15,683)	(15,942)	12,848	149,030	(13,026)	(9,127)	(9,304)	(33,602)	117,573	(31,141)
Net (loss) income	$ (21,574)	$ (15,906)	$ (14,091)	$ 11,190	$ 120,014	$ (5,598)	$ (9,163)	$ (9,236)	$ (40,381)	$ 96,017	$ (31,180)
Basic (loss) earnings per share	$ (0.75)	$ (0.55)	$ (0.49)	$ 0.40	$ 4.29	$ (0.20)	$ (0.33)	$ (0.33)	$ (1.41)	$ 3.45	$ (1.23)
Diluted (loss) earnings per share	$ (0.75)	$ (0.55)	$ (0.49)	$ 0.35	$ 3.83	(0.20)	(0.33)	$ (0.33)	$ (1.41)	$ 3.09	$ (1.23)
EPS Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Earnings Per Share, Basic and Diluted						$ 0.66	$ 0