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Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2017	Aug. 03, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q2
Trading Symbol	ITEK
Entity Registrant Name	Inotek Pharmaceuticals Corporation
Entity Central Index Key	0001281895
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		27,010,202

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 27,610	$ 29,798
Short-term investments	81,144	96,675
Prepaid expenses and other current assets	1,067	1,876
Total current assets	109,821	128,349
Property and equipment, net	1,076	1,130
Other assets	168	168
Total assets	111,065	129,647
Current liabilities:
Accounts payable	368	1,592
Accrued expenses and other current liabilities	2,423	4,416
Accrued interest	1,225	1,204
Total current liabilities	4,016	7,212
Other long-term liabilities	277	307
Total liabilities	53,535	56,479
Commitments and Contingencies (Note 7)
Stockholders’ equity:
Preferred Stock, $0.001 par value: 5,000,000 shares authorized and no shares issued or outstanding
Common stock, $0.01 par value: 120,000,000 shares authorized at June 30, 2017 and December 31, 2016; 27,010,202 and 26,986,318 shares issued and outstanding at June 30, 2017 and December 31, 2016, respectively	270	270
Additional paid-in capital	313,441	311,829
Accumulated deficit	(256,109)	(238,877)
Accumulated other comprehensive loss	(72)	(54)
Total stockholders’ equity	57,530	73,168
Total liabilities and stockholders’ equity	111,065	129,647
2021 Convertible Notes [Member]
Current liabilities:
2021 Convertible Notes, net of issuance costs	$ 49,242	$ 48,960

Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	27,010,202	26,986,318
Common stock, shares outstanding	27,010,202	26,986,318

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Operating expenses:
Research and development	$ (3,624)	$ (6,465)	$ (10,721)	$ (14,080)
General and administrative	(2,232)	(2,315)	(5,101)	(4,837)
Loss from operations	(5,856)	(8,780)	(15,822)	(18,917)
Interest expense	(889)		(1,765)
Interest income	183	96	355	165
Net loss	$ (6,562)	$ (8,684)	$ (17,232)	$ (18,752)
Net loss per share attributable to common stockholders—basic and diluted	$ (0.24)	$ (0.33)	$ (0.64)	$ (0.71)
Weighted-average number of shares outstanding—basic and diluted	26,994,454	26,623,280	26,990,409	26,523,337

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (6,562)	$ (8,684)	$ (17,232)	$ (18,752)
Other comprehensive income:
Net unrealized income (loss) on marketable securities		17	(18)	28
Total comprehensive loss	$ (6,562)	$ (8,667)	$ (17,250)	$ (18,724)

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net loss	$ (17,232)	$ (18,752)
Adjustments to reconcile net loss to cash used in operating activities:
Noncash interest expense	282
Noncash rent expense	(30)	(31)
Amortization of premium on marketable securities	133	112
Depreciation	124	72
Stock-based compensation	1,577	1,173
Changes in operating assets and liabilities:
Prepaid expenses and other assets	803	500
Accounts payable	(1,224)	(712)
Accrued expenses and other current liabilities	(1,972)	642
Net cash used in operating activities	(17,539)	(16,996)
Cash flows from investing activities:
Purchases of short-term investments	(27,204)	(57,414)
Proceeds from the maturities of short-term investments	42,590	28,941
Purchases of property and equipment	(70)	(236)
Net cash provided by (used in) investing activities	15,316	(28,709)
Cash flows from financing activities:
Net proceeds from issuance of common stock		4,049
Net cash provided by financing activities	35	4,182
Net change in cash and cash equivalents	(2,188)	(41,523)
Cash and cash equivalents, beginning of period	29,798	80,042
Cash and cash equivalents, end of period	27,610	38,519
Supplemental disclosure of cash flow information:
Cash paid for interest	1,462
Supplemental disclosure of noncash investing and financing activities:
Net unrealized gain (loss) on marketable securities	(18)	28
Stock Option Plans [Member]
Cash flows from financing activities:
Proceeds from issuance of common stock		88
Employee Stock Purchase Plan [Member]
Cash flows from financing activities:
Proceeds from issuance of common stock	$ 35	$ 45

Organization and Operations	6 Months Ended
Organization and Operations	Jun. 30, 2017
Accounting Policies [Abstract]
Organization and Operations	1. Organization and Operations Inotek Pharmaceuticals Corporation (the “Company”) is a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of therapies for ocular diseases, including glaucoma. The Company has been developing trabodenoson in a monotherapy and in a fixed-dose combination therapy (“FDC”) to treat glaucoma. On January 3, 2017, the Company announced that MATrX-1, its first pivotal Phase 3 trial of trabodenoson for the treatment of primary open-angle glaucoma or ocular hypertension did not meet its primary endpoint. On July 7, 2017, the Company announced its Phase 2 FDC clinical trial of trabodenoson and latanoprost for the treatment of glaucoma also did not meet its primary endpoint. The Company has voluntarily discontinued its development of trabodenoson, in view of the results of these clinical trials and engaged a financial advisor to assist in pursuing strategic alternatives. There can be no assurance a transaction will result from this process. The Company’s headquarters are located in Lexington, Massachusetts. The Company has devoted substantially all of its efforts to research and development, including clinical trials of its product candidates, primarily trabodenoson. The Company has not completed the development of any product candidates. The Company has no current source of revenue to sustain future development activities and does not expect to generate revenue until and unless the Company receives regulatory approval of and successfully commercializes its product candidates. The Company is subject to a number of risks and uncertainties similar to those of other life science companies developing new products, including, among others, the risks related to the necessity to obtain adequate additional financing, to successfully develop product candidates, to obtain regulatory approval of products candidates, to comply with government regulations, to successfully commercialize its potential products, to protect proprietary technology and to the dependence on key individuals. In April 2016, the Company filed a registration statement on Form S-3 containing two prospectuses: (i) a base prospectus which covers the offering, issuance and sale of up to $200,000 in the aggregate of an indeterminate number of shares of common stock and preferred stock, such indeterminate principal amount of debt securities and such indeterminate number of warrants and units; and (ii) a sales agreement prospectus covering the offering, issuance and sale of up to a maximum aggregate offering price of $50,000 of the Company’s common stock that may be issued and sold under an at-the-market sales agreement with Cowen and Company, LLC (the “ATM”). The $50,000 of common stock that may be issued and sold under the ATM reduces the available balance under the base prospectus by the amount issued. The Company did not sell any shares of common stock pursuant to the ATM during the three and six months ended June 30, 2017. At June 30, 2017, $45,599 was available for sale of common stock under the ATM. Additionally, in 2016 the Company issued $52,000 aggregate principal amount of 5.75% Convertible Senior Notes due 2021 pursuant to a Prospectus Supplement to its Form S-3, (the “2021 Convertible Notes”), which further reduces the balance available under the base prospectus to $98,000 as of June 30, 2017. As of June 30, 2017, the Company had an accumulated deficit of $256,109 and $108,754 of cash and cash equivalents and short-term investments. Although the Company has suspended its research and development activities, if the Company resumes the development of any product candidates, it will need to expend substantial resources for research and development, including costs associated with the clinical testing of its product candidates and will need to obtain additional financing to fund its operations and to conduct trials for its product candidates. If such products were to receive regulatory approval, the Company would need to prepare for the potential commercialization of its product candidates and fund the commercial launch and continued marketing of its products. The Company expects operating expenses may increase or decrease depending upon whether a strategic transaction is entered into, but expects aggregate operating expenses will not increase in 2017 over 2016.

Significant Accounting Policies

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Significant Accounting Policies

2. Significant Accounting Policies

Basis of Presentation—The Company’s interim financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). In the opinion of management, the Company has made all necessary adjustments, which include normal recurring adjustments necessary for a fair statement of the Company’s financial position and results of operations for the interim periods presented. Certain information and disclosures normally included in the annual financial statements prepared in accordance with GAAP have been condensed or omitted. These interim financial statements should be read in conjunction with the audited financial statements and accompanying notes for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K. The results for the three and six months ended June 30, 2017 are not necessarily indicative of the results to be expected for a full year, any other interim periods or any future year or period.

The accompanying consolidated financial statements include our accounts and those of our wholly-owned subsidiaries, Inotek Securities Corporation and Inotek Ltd. All significant intercompany balances and transactions have been eliminated in consolidation.

Segment Reporting—Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating segment.

Use of Estimates—The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from these estimates. Significant items subject to such estimates and assumptions include the valuation of stock options used for the calculation of stock-based compensation and calculation of accruals related to research and clinical development.

Comprehensive loss—Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions, and other events and circumstances from non-owner sources, and currently consists of net loss and changes in unrealized gains and losses on short-term investments. Accumulated other comprehensive loss consists entirely of unrealized gains and losses from short-term investments as of June 30, 2017 and December 31, 2016.

Cash and Cash Equivalents—Cash and cash equivalents consist of bank deposits, certificates of deposit and money market accounts. Cash equivalents are carried at cost which approximates fair value due to their short-term nature and which the Company believes do not have a material exposure to credit risk. The Company considers all highly liquid investments with maturities of three months or less from the date of purchase to be cash equivalents.

The Company maintains its cash and cash equivalent balances in the form of money market, savings or operating accounts with financial institutions that management believes are creditworthy. The Company’s cash and cash equivalent accounts, at times, may exceed federally insured limits. The Company has not experienced any losses in such accounts. The Company believes it is not exposed to any significant credit risk on cash and cash equivalents.

Short-term Investments—Short-term investments consist of investments in certificates of deposit, agency bonds and United States Treasury securities. Management determines the appropriate classification of these securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its short-term investments as available-for-sale pursuant to Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) 320, Investments—Debt and Equity Securities. Short-term investments are recorded at fair value, with unrealized gains and losses included as a component of accumulated other comprehensive loss in stockholders’ equity and a component of total comprehensive loss in the consolidated statements of comprehensive loss, until realized. Realized gains and losses are included in investment income on a specific-identification basis. There were no realized gains or losses on short-term investments for the three and six months ended June 30, 2017 and 2016. There were no unrealized gains or losses on short term investments for the three months ended June 30, 2017, and $18 of net unrealized losses on short-term investments for the six months ended June 30, 2017. There were $17 and $28 of net unrealized gains on short-term investments for the three and six months ended June 30, 2016.

The Company reviews short-term investments for other-than-temporary impairment whenever the fair value of a short-term investment is less than the amortized cost and evidence indicates that a short-term investment’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the short-term investment, or if it is more likely than not that the Company will be required to sell the short-term investment before recovery of the amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, compliance with the Company’s investment policy, the severity and the duration of the impairment and changes in value subsequent to the end of the period.

Short-term investments at June 30, 2017 consist of the following:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Current:
Certificates of deposit	$	17,039	$	—	$	—		$	17,039
Agency bonds		5,915		—		(3	)		5,912
United States Treasury securities		58,262		—		(69	)		58,193
	$	81,216	$	—	$	(72	)	$	81,144

Short-term investments at December 31, 2016 consist of the following:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Current:
Certificates of deposit	$	22,046	$	—	$	—		$	22,046
Agency bonds		5,917		—		(4	)		5,913
United States Treasury securities		68,766		1		(51	)		68,716
	$	96,729	$	1	$	(55	)	$	96,675

At June 30, 2017 and December 31, 2016, all short-term investments held by the Company had contractual maturities of less than one year. The Company evaluated its securities for other-than-temporary impairment and determined that no such impairment existed at June 30, 2017 and December 31, 2016.

Property and Equipment—Property and equipment are stated at cost. Expenditures for repairs and maintenance are charged to expense as incurred. Upon retirement or sale, the cost of the assets disposed of and the related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is reflected in the consolidated statement of operations. Depreciation and amortization is provided using the straight-line method over the estimated useful lives of the assets.

Debt Issuance Costs—Debt issuance costs consist of underwriting discounts and offering-related costs incurred by the Company in connection with the closing of the 2021 Convertible Notes and are included as a direct deduction from the carrying amount of the 2021 Convertible Notes on the Company’s consolidated balance sheets. The Company amortizes debt issuance costs to interest expense over the life of the 2021 Convertible Notes using the effective interest method. (See Note 5). Amortization of debt issuance costs was $143 and $282 in the three and six months ended June 30, 2017.

Research and Development Costs—Research and development costs are charged to expense as incurred and include, but are not limited to:

•

employee-related expenses including salaries, benefits, travel and stock-based compensation expense for research and development personnel;

•

expenses incurred under agreements with contract research organizations that conduct clinical and preclinical studies, contract manufacturing organizations and consultants;

•

costs associated with preclinical and development activities; and

•

costs associated with regulatory operations.

Costs for certain development activities, such as clinical studies, are recognized based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations, and information provided to the Company by its vendors on their actual costs incurred. Payments for these activities are based on the terms of the individual arrangements, which may differ from the patterns of costs incurred, and are reflected in the financial statements as accrued expenses, or prepaid expenses and other current assets, if the related services have not been provided.

Stock-Based Compensation—The Company measures the cost of employee services received in exchange for an award of equity instruments based on the fair value of the award on the grant date. That cost is recognized on a straight-line basis over the period during which the employee is required to provide service in exchange for the award. The fair value of options on the date of grant is calculated using the Black-Scholes option pricing model based on key assumptions such as stock price, expected volatility and expected term. The Company’s estimates of these assumptions are primarily based on the trading price of the Company’s stock, historical data, peer company data and judgment regarding future trends and factors. The fair value of restricted stock awards is based on the intrinsic value of such awards on the date of grant. Compensation cost for stock purchase rights under the employee stock purchase plan is measured and recognized on the date the Company becomes obligated to issue shares of our common stock and is based on the difference between the fair value of the Company’s common stock and the purchase price on such date.

The Company accounts for stock options issued to non-employees in accordance with the provisions of FASB ASC 505-50, Equity-Based Payments to Non-employees, which requires valuing the stock options on their grant date and measuring such stock options at their current fair value as they vest.

Fair Value Measurements—The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. FASB ASC 820, Fair Value Measurements and Disclosures (“ASC 820”), establishes a hierarchy of inputs used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability, and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below:

Level 1—Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly.

Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable.

To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The fair value of the Company’s financial instruments, including cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued expenses approximate their respective carrying values due to the short-term nature of these instruments. The Company’s assets and liabilities measured at fair value on a recurring basis include its short-term investments.

Net Loss Per Share—The Company calculates net loss per share in accordance with FASB ASC 260, Earnings per Share. Basic earnings (loss) per share (“EPS”) is calculated by dividing the net income or loss applicable to common stockholders by the weighted average number of common shares outstanding for the period, without consideration of unissued common stock equivalents. The net loss applicable to common stockholders is determined by the reported net loss for the period and deducting dividends accrued and accretion of preferred stock. Diluted EPS is calculated by adjusting the weighted average common shares outstanding for the dilutive effect of common stock options, warrants, and convertible preferred stock and accrued but unpaid convertible preferred stock dividends. In periods where a net loss is recorded, no effect is given to potentially dilutive securities, as their effect would be anti-dilutive.

The following table sets forth the computation of basic and diluted EPS attributable to the Company’s common stockholders:

	For the Three Months Ended June 30,						For the Six Months Ended June 30,
	2017			2016			2017			2016
Numerator:
Net loss applicable to common stockholders	$	(6,562	)	$	(8,684	)	$	(17,232	)	$	(18,752	)

Denominator:
Weighted average common shares outstanding - basic and diluted		26,994,454			26,623,280			26,990,409			26,523,337
Net loss per share applicable to common stockholders - basic and diluted	$	(0.24	)	$	(0.33	)	$	(0.64	)	$	(0.71	)

The following common stock equivalents were excluded from the calculation of diluted net loss per share for the periods indicated as including them would have an anti-dilutive effect:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Shares issuable upon conversion of the 2021 Convertible Notes		6,483,791		—		6,483,791		—
Warrants exerciseable for common stock		56,408		56,408		56,408		56,408
Stock options		2,586,351		2,538,320		2,586,351		2,538,320
Restricted Stock Units		1,312,500		—		1,312,500		—
Total		10,439,050		2,594,728		10,439,050		2,594,728

Subsequent Events—The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The Company has completed an evaluation of all subsequent events through the date the financial statements were issued (see Note 9).

Recent Accounting Pronouncements—In February 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842), which supersedes the current leasing guidance and upon adoption, will require lessees to recognize right-of-use assets and lease liabilities on the balance sheet for all leases with terms longer than 12 months. The new standard is effective for the Company for the annual period beginning after December 15, 2018, and can be early adopted by applying a modified retrospective approach for leases existing at, and entered into after, the beginning of the earliest comparable period presented in the financial statements. The Company is currently evaluating the impact of this accounting standard update on the Company’s consolidated financial statements.

In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which amends FASB ASC Topic 718, Compensation – Stock Compensation (“ASC 718”), and includes provisions intended to simplify various aspects related to how share-based payments are accounted for and presented in the financial statements. The new standard is effective for the Company for the annual period beginning after December 15, 2016, and for annual and interim periods thereafter, with early adoption permitted. The Company adopted this standard on January 1, 2017.

The update revises requirements in the following areas: minimum statutory withholding, accounting for income taxes, and forfeitures. Prior to adoption, the Company applied a 0% forfeiture rate to share-based compensation, resulting in no cumulative effect adjustment to the opening period. Upon adoption of ASU 2016-09, the Company’s accounting policy is to recognize forfeitures as they occur. The update also requires the Company to recognize the income tax effect of awards in the income statement when the awards vest or are settled. Finally, the update allows the Company to repurchase more of an employee’s shares than it can today for tax withholding purposes without triggering a liability. The income tax related items had no effect on the current period presentation and the Company maintains a full valuation allowance against its deferred tax assets.

Property and Equipment

6 Months Ended

Jun. 30, 2017

Property Plant And Equipment [Abstract]

Property and Equipment

3. Property and Equipment

At June 30, 2017 and December 31, 2016, the Company’s property and equipment consisted of the following:

	Useful lives	June 30, 2017			December 31, 2016
Office equipment	5 years	$	357		$	407
Computer hardware and software	3 - 7 years		96			263
Laboratory equipment	5 years		516			446
Leasehold improvements	7 years		445			445
Total			1,414			1,561
Less: accumulated depreciation			(338	)		(431	)
Property and equipment, net		$	1,076		$	1,130

During the three and six months ended June 30, 2017, the Company recognized $63 and $124 of depreciation expense, respectively, and wrote off $217 of fully depreciated net assets. During the three and six months ended June 30, 2016, the Company recognized $36 and $72 of depreciation expense, respectively.

Accrued Expenses and Other Current Liabilities

6 Months Ended

Jun. 30, 2017

Payables And Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

4. Accrued Expenses and Other Current Liabilities

At June 30, 2017 and December 31, 2016, the Company’s accrued expenses and other current liabilities consisted of the following:

	June 30, 2017		December 31, 2016
Compensation and benefits	$	1,098	$	2,171
Research and development		367		1,148
Government payable		492		478
Professional fees		208		311
Other		258		308
Total	$	2,423	$	4,416

Debt

6 Months Ended

Jun. 30, 2017

Debt Disclosure [Abstract]

Debt

5. Debt

2021 Convertible Notes

On August 5, 2016, the Company issued an aggregate of $50,000 of the 2021 Convertible Notes. On August 30, 2016, the Company issued an additional $2,000 of 2021 Convertible Notes pursuant to the exercise of the underwriters’ overallotment option. The 2021 Convertible Notes have a maturity date of August 1, 2021 (“Maturity Date”), are unsecured and accrue interest at a rate of 5.75% per annum, payable semi-annually on February 1 and August 1 of each year, beginning February 1, 2017. In connection with the issuance of the 2021 Convertible Notes, the Company incurred $3,262 of debt issuance costs which were recorded as a discount on the 2021 Convertible Notes.

Each holder of a 2021 Convertible Note (the “Holder”) has the option until the close of business on the second business day immediately preceding the Maturity Date to convert all, or any portion, of the 2021 Convertible Notes held by it at an initial conversion rate of 124.7505 shares of the Company’s common stock per $1 principal amount of 2021 Convertible Notes (the “Conversion Rate”). The Conversion Rate is subject to adjustment from time to time upon the occurrence of certain events, including the issuance of stock dividends and payment of cash dividends. In addition, in certain circumstances, the Conversion Rate will be increased in respect of a Holder’s conversion of 2021 Convertible Notes in connection with the occurrence of one or more corporate events specified in the indenture (as supplemented, the “Indenture”) governing the 2021 Convertible Notes (each such specified corporate event, a “Make-Whole Fundamental Change”) that occurs prior to the Maturity Date (a “Make-Whole Fundamental Change Conversion”) or in respect of a Holder’s voluntary conversion of 2021 Convertible Notes other than in connection with a Make-Whole Fundamental Change (a “Voluntary Conversion”). In connection with a Make-Whole Fundamental Change Conversion or a Voluntary Conversion, the Company will increase the Conversion Rate for the 2021 Convertible Notes surrendered for conversion by a number of additional shares of the Company’s common stock set forth in the Additional Shares Make-Whole Table in the Indenture, based on the applicable Stock Price (as defined in the Indenture) and Effective Date (as defined in the Indenture) for such conversion. The additional shares potentially issuable in connection with a Make-Whole Fundamental Change Conversion or a Voluntary Conversion range from 0 to 24.95 per $1 principal amount of 2021 Convertible Notes, subject to adjustment. If the Stock Price applicable to any conversion is greater than $40.00 per share, the Conversion Rate will not be increased. If the Stock Price applicable to any conversion is less than $6.68 per share, the Conversion Rate in connection with a Make-Whole Fundamental Change Conversion will not be increased but it will be increased by 24.95 shares in connection with a Voluntary Conversion. Upon conversion, Holders of the 2021 Convertible Notes will receive shares of the Company’s common stock and cash in lieu of fractional shares.

Upon the occurrence of a Fundamental Change, the occurrence of certain change of control transactions or delisting events (as defined in the Indenture), each Holder may require the Company to repurchase for cash all or any portion of the 2021 Convertible Notes held by such Holder at a repurchase price equal to 100% of the principal amount thereof, plus accrued and unpaid interest thereon.

The Company, at its option, may redeem for cash all or any portion of the 2021 Convertible Notes if the last reported sale price of a share of the Company’s common stock is equal to or greater than 200% of the conversion price for the 2021 Convertible Notes then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period (including the last trading day of such period) ending within the five trading days immediately preceding the date on which the Company provides notice of redemption, at a redemption price equal to 100% of the principal amount of the 2021 Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date.

If an Event of Default (as defined in the Indenture), other than certain events of bankruptcy, insolvency or reorganization involving the Company, occurs and is continuing, the trustee under the Indenture (the “Trustee”) or the Holders of at least 25% in principal amount of the outstanding 2021 Convertible Notes may declare 100% of the principal of and accrued and unpaid interest, if any, on all of the 2021 Convertible Notes to be due and payable immediately. Upon the occurrence of an Event of Default relating to bankruptcy, insolvency or reorganization involving the Company, 100% of the principal of and accrued and unpaid interest, if any, on all of the 2021 Convertible Notes would become due and payable automatically.

Notwithstanding the foregoing, the Indenture provides that, to the extent the Company elects, the sole remedy for an Event of Default relating to certain failures by the Company to comply with certain reporting covenants in the Indenture, will (i) for the first 90 days after the occurrence of such an Event of Default, consist exclusively of the right to receive additional interest on the 2021 Convertible Notes at a rate equal to 0.25% per annum of the principal amount of the 2021 Convertible Notes outstanding for each day during such 90-day period on which such an Event of Default is continuing and (ii) for the period from, and including, the 91st day after the occurrence of such an Event of Default to, and including, the 180th day after the occurrence of such an Event of Default, consist exclusively of the right to receive additional interest on the 2021 Convertible Notes at a rate equal to 0.50% per annum of the principal amount of the 2021 Convertible Notes outstanding for each day during such additional 90-day period on which such an Event of Default is continuing (such additional interest, “Additional Interest”). After 180 days, if such Event of Default is not cured or waived, the 2021 Convertible Notes would be subject to acceleration in accordance with the Indenture.

The 2021 Convertible Notes are considered a hybrid financial instrument consisting of a fixed interest rate “host” and various embedded features that required evaluation as potential embedded derivatives under FASB ASC 815, Derivatives and Hedging (“ASC 815”). Based on the nature of the host instrument and the embedded features, management concluded that none of the conversion, put and redemption features required bifurcation and separate accounting from the host instrument. The Company determined that the Additional Interest was an embedded derivative that contains non-credit related events of default. As a result, the Additional Interest feature required bifurcation and separate accounting under ASC 815. Based on the amount of Additional Interest that would be owed and the likelihood of occurrence, the Company estimated the fair value of the Additional Interest feature to be insignificant as of June 30, 2017 and December 31, 2016.

The issuance costs which were recorded as a discount on the debt are being amortized to interest expense over the life of the 2021 Convertible Notes using the effective interest method. As of June 30, 2017, the stated interest rate was 5.75%, and the effective interest rate was 7.3%. For the three months ended June 30, 2017, interest expense related to the 2021 Convertible Notes was $889, including $143 related to amortization of the debt discount. For the six months ended June 30, 2017, interest expense related to the 2021 Convertible Notes was $1,765, including $282 related to amortization of the debt discount.

The table below summarizes the carrying value of the 2021 Convertible Notes as of June 30, 2017:

	June 30, 2017
Gross proceeds	$	52,000
Initial value of issuance costs recorded as debt discount		(3,262	)
Amortization of debt discount		504
Carrying value	$	49,242

Equity

6 Months Ended

Jun. 30, 2017

Equity [Abstract]

Equity

6. Equity

Authorized Shares

As of June 30, 2017, the Company’s authorized capital stock consisted of 120,000,000 shares of common stock, par value $0.01 per share, and 5,000,000 shares of undesignated preferred stock, par value $0.001 per share.

Common Stock

All preferences, voting powers, relative, participating, optional, or other specific rights and privileges, limitations, or restrictions of the common stock are expressly subject to those that may be fixed with respect to any shares of preferred stock. Common stockholders are entitled to one vote per share, and to receive dividends, when and if declared by the Company’s board of directors. At June 30, 2017 and December 31, 2016, there were 27,010,202 and 26,986,318 shares of common stock outstanding, respectively.

Equity Plans

The Company maintains three equity compensation plans: the 2014 Stock Option and Incentive Plan (the “2014 Plan”), the 2004 Stock Option and Incentive Plan (the “2004 Plan”) and the 2014 Employee Stock Purchase Plan (“ESPP”).

2014 Stock Option and Incentive Plan

The 2014 Plan provides for the issuance of incentive and non-qualified stock options, restricted stock, and other equity awards, all for common stock, as determined by the board of directors to employees, officers, directors, consultants, and advisors of the Company and its subsidiaries. Pursuant to the provisions of the 2014 Plan and approval by the board of directors, on January 1, 2017 an additional 1,079,453 shares were added to the 2014 Plan representing 4% of total common shares issued and outstanding at December 31, 2016. There were 326,812 shares available for issuance under the 2014 Plan as of June 30, 2017. The 2014 Plan expires in August 2024.

In December 2016, the board granted to certain executive officers an aggregate of 470,000 RSU’s pursuant to the 2014 Plan. Each restricted stock unit represents a contingent right to receive one share of Company common stock. Vesting for these RSU’s was based equally on the achievement of two performance-based conditions, subject to continued service through such achievement dates. The intrinsic fair value of these RSU’s as of the date of grant was $3,055 and no stock-based compensation expense was recorded in 2016 as the Company determined that the vesting conditions were not probable of occurring. In January 2017, these RSU’s were modified such that instead of vesting based on the achievement of certain performance-based conditions, they will vest in equal annual installments over four years from the December 2016 date of grant, subject to continued service through such dates. This change in vesting criteria was accounted for as a modification under ASC 718 whereby the Company will recognize the $717 fair value of the grants as of the date of modification over the vesting term.

The following table summarizes stock option activity under the 2014 Plan:

	Number of Shares			Weighted Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding at December 31, 2016		2,664,832		$	6.16
Granted		315,000		$	1.80
Exercised		—
Cancelled		(401,826	)	$	6.95
Outstanding at June 30, 2017		2,578,006		$	5.50	$	31,500

Exercisable at June 30, 2017		1,279,252		$	5.57	$	—
Weighted-average years remaining on contractual life		8.27
Unrecognized compensation cost related to non-vested stock options	$	6,108

The weighted-average fair value of all stock options granted for the three and six months ended June 30, 2017 was $1.80 per share. Aggregate intrinsic value at June 30, 2017, is based on $1.90 per share, the closing price of common stock on June 30, 2017.

The following table summarizes RSU activity under the 2014 Plan:

	Number of Shares			Weighted Average Grant Date Fair Value Per Share
Outstanding at December 31, 2016		470,000		$	6.50
Granted		931,000		$	1.60
Vested		—
Cancelled		(88,500	)	$	1.70
Outstanding at June 30, 2017		1,312,500		$	1.57

The weighted average grant date fair value per share of outstanding RSU’s as of June 30, 2017 reflects the $1.53 per share fair value of the modified RSU’s as of the date of modification.

2004 Stock Option and Incentive Plan

The following table summarizes stock option activity under the 2004 Plan:

	Number of Shares			Weighted Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding at December 31, 2016		10,626		$	40.58
Exercised		—
Expired		(2,281	)	$	40.58
Cancelled		—
Outstanding at June 30, 2017		8,345		$	40.58	$	—

Exercisable at June 30, 2017		8,345		$	40.58	$	—
Weighted-average years remaining on contractual life		1.03
Unrecognized compensation cost related to non-vested stock options	$	—

The exercise prices exceed the $1.90 per share closing price of common stock on June 30, 2017, therefore there is no intrinsic value of the outstanding 2004 Plan stock options.

Employee Stock Purchase Plan

In November 2014, the Company’s board of directors adopted and the stockholders approved the 2014 Employee Stock Purchase Plan (“ESPP”). The ESPP provides that the number of shares reserved and available for issuance under the ESPP shall be cumulatively increased each January 1, beginning on January 1, 2016, by the lesser of (i) 600,000 shares of common stock or (ii) the number of shares necessary to set the number of shares of Common Stock under the Plan at 1% percent of the outstanding number of shares as of January 1 of the applicable year. However, the board of directors reserves the right to determine that there will be no increase for any year or that any increase will be for a lesser number of shares. As of January 1, 2017, 31,555 shares were added to the ESPP. As of June 30, 2017, there were 245,979 shares available for issuance under the ESPP.

On May 31, 2017, 23,884 shares of common stock were purchased pursuant to the ESPP, resulting in proceeds to the Company of $35. The Company recorded $0 and $25 of stock-based compensation expense pursuant to the ESPP during the three and six months ended June 30, 2017, respectively, and $0 and $20 of stock-based compensation expense pursuant to the ESPP during the three and six months ended June 30, 2016, respectively.

Stock-Based Compensation

Stock-based compensation expense for options, restricted stock units (“RSU’s”) and the ESPP is reflected in the consolidated statements of operations as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Research and development	$	292	$	316	$	595	$	525
General and administrative		501		370		982		648
Total	$	793	$	686	$	1,577	$	1,173

Commitments and Contingencies

6 Months Ended

Jun. 30, 2017

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

7. Commitments and Contingencies

Operating lease

In 2015, the Company entered into a lease agreement (the “Office Lease”) for its headquarters in Lexington, Massachusetts. The Company recorded $445 as leasehold improvements for costs incurred to build out the space, and is amortizing those costs to facilities expense over the term of the lease. Rent expense is recognized on a straight-line basis at the average monthly rent over the term of the lease. Deferred rent is included in other current and long-term liabilities on the Company’s consolidated balance sheets.

In 2016, the Company signed an amendment to the Office Lease, whereby it agreed to rent additional space (the “Lease Amendment”). The terms of the Lease Amendment follow the terms of the Office Lease. The lease term is 90 months and the Company has the right to extend the term for one period of five years.

The Company recorded rent expense of $84 and $169 for the three and six months ended June 30, 2017, respectively, and $62 and $124 for the three and six months ended June 30, 2016, respectively. As of June 30, 2017, the aggregate annual commitments pursuant to the Office Lease and the Lease Amendment are as follows:

Year	Amount
2017	$	202
2018		411
2019		421
2020		430
2021		439
Thereafter		520
Total	$	2,423

Securities Litigation

On January 6, 2017, a purported stockholder of the Company filed a putative class action in the U.S. District Court for the District of Massachusetts, captioned Whitehead v. Inotek Pharmaceuticals Corporation, et al., No. 1:17-cv-10025. An amended complaint was filed on July 10, 2017. The amended complaint alleges violations of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and SEC Rule 10b-5 against the Company, David Southwell, and Rudolf Baumgartner based on allegedly false and misleading statements and omissions regarding our phase 2 and phase 3 clinical trials of trabodenoson. The lawsuit seeks among other things, unspecified compensatory damages for purchasers of the Company’s common stock between July 23, 2015 and December 30, 2016, as well as interest and attorneys’ fees and costs. The Company intends to vigorously defend itself against this claim.

Indemnification Arrangements

As permitted under Delaware law, the Company’s bylaws provide that the Company will indemnify any director, officer, employee or agent of the Company or anyone serving in these capacities. The maximum potential amount of future payments the Company could be required to pay is unlimited. The Company has insurance that reduces its monetary exposure and would enable it to recover a portion of any future amounts paid. As a result, the Company believes that the estimated fair value of these indemnification commitments is minimal.

Throughout the normal course of business, the Company has agreements with vendors that provide goods and services required by the Company to run its business. In some instances, vendor agreements include language that requires the Company to indemnify the vendor from certain damages caused by the Company’s use of the vendor’s goods and/or services. The Company has insurance that would allow it to recover a portion of any future amounts that could arise from these indemnifications. As a result, the Company believes that the estimated fair value of these indemnification commitments is minimal.

Fair Value of Financial Measurements

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Fair Value of Financial Measurements

8. Fair Value of Financial Measurements

Items measured at fair value on a recurring basis are short-term investments. The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy:

	Fair Value Measurements at
	June 30, 2017
	Total		Level 1		Level 2		Level 3
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	21,581	$	21,581	$	—	$	—

Certificates of deposit	$	17,039	$	—	$	17,039	$	—
Agency bonds		5,912		—		5,912		—
United States Treasury securities		58,193		58,193		—		—
Short-term investments	$	81,144	$	58,193	$	22,951	$	—

	Fair Value Measurements at
	December 31, 2016
	Total		Level 1		Level 2		Level 3
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	20,698	$	20,698	$	—	$	—

Certificates of deposit	$	22,046	$	—	$	22,046	$	—
Agency bonds		5,913		—		5,913		—
United States Treasury securities		68,716		68,716		—		—
Short-term investments	$	96,675	$	68,716	$	27,959	$	—

Money market mutual funds

The Company classifies its money market mutual funds as Level 1 assets under the fair value hierarchy as these assets have been valued using quoted market prices in active markets without any valuation adjustment.

Short-term investments

The Company classifies its United States Treasury securities as Level 1 assets under the fair value hierarchy as these assets have been valued using quoted market prices in active markets without any valuation adjustment. The Company classifies its certificates of deposit as Level 2 assets under the fair value hierarchy, as there are no quoted market prices in active markets, and its agency bonds as Level 2 assets under the fair value hierarchy, as these assets are not always valued daily using quoted market prices in active markets.

Subsequent Event	6 Months Ended
Subsequent Event	Jun. 30, 2017
Subsequent Events [Abstract]
Subsequent Event	9. Subsequent Event On January 3, 2017, the Company announced that MATrX-1, its first pivotal Phase 3 trial of trabodenoson for the treatment of primary open-angle glaucoma or ocular hypertension did not meet its primary endpoint. On July 7, 2017, the Company announced its Phase 2 FDC clinical trial of trabodenoson and latanoprost for the treatment of glaucoma also did not meet its primary endpoint. In view of the results of these clinical trials, the Company has voluntarily discontinued its development of trabodenoson. The Company owns certain equipment to produce clinical supplies of trabodenoson. As of June 30, 2017, this equipment has a net book value of $437. The Company believes the value of this equipment has been impaired as a result of the Company’s decision to discontinue development of trabodenoson and expects to take a charge to operations for a write-down of this equipment to net realizable value in the three months ending September 30, 2017.

Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Basis of Presentation

Segment Reporting

Use of Estimates

Comprehensive loss

Cash and Cash Equivalents

Short-term Investments

Short-term investments at June 30, 2017 consist of the following:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Current:
Certificates of deposit	$	17,039	$	—	$	—		$	17,039
Agency bonds		5,915		—		(3	)		5,912
United States Treasury securities		58,262		—		(69	)		58,193
	$	81,216	$	—	$	(72	)	$	81,144

Short-term investments at December 31, 2016 consist of the following:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Current:
Certificates of deposit	$	22,046	$	—	$	—		$	22,046
Agency bonds		5,917		—		(4	)		5,913
United States Treasury securities		68,766		1		(51	)		68,716
	$	96,729	$	1	$	(55	)	$	96,675

Property and Equipment

Debt Issuance Costs

Research and Development Costs

Research and Development Costs—Research and development costs are charged to expense as incurred and include, but are not limited to:

•

employee-related expenses including salaries, benefits, travel and stock-based compensation expense for research and development personnel;

•

expenses incurred under agreements with contract research organizations that conduct clinical and preclinical studies, contract manufacturing organizations and consultants;

•

costs associated with preclinical and development activities; and

•

costs associated with regulatory operations.

Stock-Based Compensation

Fair Value Measurements

Level 1—Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly.

Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable.

Net Loss Per Share

The following table sets forth the computation of basic and diluted EPS attributable to the Company’s common stockholders:

	For the Three Months Ended June 30,						For the Six Months Ended June 30,
	2017			2016			2017			2016
Numerator:
Net loss applicable to common stockholders	$	(6,562	)	$	(8,684	)	$	(17,232	)	$	(18,752	)

Denominator:
Weighted average common shares outstanding - basic and diluted		26,994,454			26,623,280			26,990,409			26,523,337
Net loss per share applicable to common stockholders - basic and diluted	$	(0.24	)	$	(0.33	)	$	(0.64	)	$	(0.71	)

The following common stock equivalents were excluded from the calculation of diluted net loss per share for the periods indicated as including them would have an anti-dilutive effect:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Shares issuable upon conversion of the 2021 Convertible Notes		6,483,791		—		6,483,791		—
Warrants exerciseable for common stock		56,408		56,408		56,408		56,408
Stock options		2,586,351		2,538,320		2,586,351		2,538,320
Restricted Stock Units		1,312,500		—		1,312,500		—
Total		10,439,050		2,594,728		10,439,050		2,594,728

Subsequent Events

Recent Accounting Pronouncements

Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Schedule of Short-term Investment

Short-term investments at June 30, 2017 consist of the following:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Current:
Certificates of deposit	$	17,039	$	—	$	—		$	17,039
Agency bonds		5,915		—		(3	)		5,912
United States Treasury securities		58,262		—		(69	)		58,193
	$	81,216	$	—	$	(72	)	$	81,144

Short-term investments at December 31, 2016 consist of the following:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Current:
Certificates of deposit	$	22,046	$	—	$	—		$	22,046
Agency bonds		5,917		—		(4	)		5,913
United States Treasury securities		68,766		1		(51	)		68,716
	$	96,729	$	1	$	(55	)	$	96,675

Schedule of Computation of Basic and Diluted EPS

The following table sets forth the computation of basic and diluted EPS attributable to the Company’s common stockholders:

	For the Three Months Ended June 30,						For the Six Months Ended June 30,
	2017			2016			2017			2016
Numerator:
Net loss applicable to common stockholders	$	(6,562	)	$	(8,684	)	$	(17,232	)	$	(18,752	)

Denominator:
Weighted average common shares outstanding - basic and diluted		26,994,454			26,623,280			26,990,409			26,523,337
Net loss per share applicable to common stockholders - basic and diluted	$	(0.24	)	$	(0.33	)	$	(0.64	)	$	(0.71	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

The following common stock equivalents were excluded from the calculation of diluted net loss per share for the periods indicated as including them would have an anti-dilutive effect:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Shares issuable upon conversion of the 2021 Convertible Notes		6,483,791		—		6,483,791		—
Warrants exerciseable for common stock		56,408		56,408		56,408		56,408
Stock options		2,586,351		2,538,320		2,586,351		2,538,320
Restricted Stock Units		1,312,500		—		1,312,500		—
Total		10,439,050		2,594,728		10,439,050		2,594,728

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details

Property and Equipment (Tables)

6 Months Ended

Jun. 30, 2017

Property Plant And Equipment [Abstract]

Schedule of Property and Equipment

At June 30, 2017 and December 31, 2016, the Company’s property and equipment consisted of the following:

	Useful lives	June 30, 2017			December 31, 2016
Office equipment	5 years	$	357		$	407
Computer hardware and software	3 - 7 years		96			263
Laboratory equipment	5 years		516			446
Leasehold improvements	7 years		445			445
Total			1,414			1,561
Less: accumulated depreciation			(338	)		(431	)
Property and equipment, net		$	1,076		$	1,130

Accrued Expenses and Other Current Liabilities (Tables)

6 Months Ended

Jun. 30, 2017

Payables And Accruals [Abstract]

Schedule of Accrued Expenses and Other Current Liabilities

At June 30, 2017 and December 31, 2016, the Company’s accrued expenses and other current liabilities consisted of the following:

	June 30, 2017		December 31, 2016
Compensation and benefits	$	1,098	$	2,171
Research and development		367		1,148
Government payable		492		478
Professional fees		208		311
Other		258		308
Total	$	2,423	$	4,416

Debt (Tables)

6 Months Ended

Jun. 30, 2017

Debt Disclosure [Abstract]

Summary of Carrying Value of Convertible Notes

The table below summarizes the carrying value of the 2021 Convertible Notes as of June 30, 2017:

	June 30, 2017
Gross proceeds	$	52,000
Initial value of issuance costs recorded as debt discount		(3,262	)
Amortization of debt discount		504
Carrying value	$	49,242

Equity (Tables)

6 Months Ended

Jun. 30, 2017

Equity [Abstract]

Summary of Stock Option Activity

The following table summarizes stock option activity under the 2014 Plan:

	Number of Shares			Weighted Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding at December 31, 2016		2,664,832		$	6.16
Granted		315,000		$	1.80
Exercised		—
Cancelled		(401,826	)	$	6.95
Outstanding at June 30, 2017		2,578,006		$	5.50	$	31,500

Exercisable at June 30, 2017		1,279,252		$	5.57	$	—
Weighted-average years remaining on contractual life		8.27
Unrecognized compensation cost related to non-vested stock options	$	6,108

The following table summarizes stock option activity under the 2004 Plan:

	Number of Shares			Weighted Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding at December 31, 2016		10,626		$	40.58
Exercised		—
Expired		(2,281	)	$	40.58
Cancelled		—
Outstanding at June 30, 2017		8,345		$	40.58	$	—

Exercisable at June 30, 2017		8,345		$	40.58	$	—
Weighted-average years remaining on contractual life		1.03
Unrecognized compensation cost related to non-vested stock options	$	—

Summary of RSU Activity

The following table summarizes RSU activity under the 2014 Plan:

	Number of Shares			Weighted Average Grant Date Fair Value Per Share
Outstanding at December 31, 2016		470,000		$	6.50
Granted		931,000		$	1.60
Vested		—
Cancelled		(88,500	)	$	1.70
Outstanding at June 30, 2017		1,312,500		$	1.57

Schedule of Stock-Based Compensation Expense

Stock-based compensation expense for options, restricted stock units (“RSU’s”) and the ESPP is reflected in the consolidated statements of operations as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Research and development	$	292	$	316	$	595	$	525
General and administrative		501		370		982		648
Total	$	793	$	686	$	1,577	$	1,173

Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2017

Commitments And Contingencies Disclosure [Abstract]

Schedule of Aggregate Annual Commitments Pursuant to Office Lease and Lease Amendment

As of June 30, 2017, the aggregate annual commitments pursuant to the Office Lease and the Lease Amendment are as follows:

Year	Amount
2017	$	202
2018		411
2019		421
2020		430
2021		439
Thereafter		520
Total	$	2,423

Fair Value of Financial Measurements (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Fair Value of Assets and Liabilities Measured on Recurring Basis

The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy:

	Fair Value Measurements at
	June 30, 2017
	Total		Level 1		Level 2		Level 3
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	21,581	$	21,581	$	—	$	—

Certificates of deposit	$	17,039	$	—	$	17,039	$	—
Agency bonds		5,912		—		5,912		—
United States Treasury securities		58,193		58,193		—		—
Short-term investments	$	81,144	$	58,193	$	22,951	$	—

	Fair Value Measurements at
	December 31, 2016
	Total		Level 1		Level 2		Level 3
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	20,698	$	20,698	$	—	$	—

Certificates of deposit	$	22,046	$	—	$	22,046	$	—
Agency bonds		5,913		—		5,913		—
United States Treasury securities		68,716		68,716		—		—
Short-term investments	$	96,675	$	68,716	$	27,959	$	—

Organization and Operations - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Aug. 05, 2016	Apr. 30, 2016
Schedule Of Description Of Business [Line Items]
Accumulated deficit	$ (256,109,000)	$ (256,109,000)	$ (238,877,000)
Aggregate cash and cash equivalents and marketable securities	$ 108,754,000	$ 108,754,000
2021 Convertible Notes [Member] \| Senior Notes [Member]
Schedule Of Description Of Business [Line Items]
Aggregate principal amount				$ 50,000,000
Convertible senior notes, interest rate, stated percentage	5.75%	5.75%
Cowen and Company, LLC [Member]
Schedule Of Description Of Business [Line Items]
Number of shares of common stock sold	0	0
Available for sale of common stock	$ 45,599,000	$ 45,599,000
Amount of stock transactions, available balance under base prospectus	$ 98,000,000	$ 98,000,000
Cowen and Company, LLC [Member] \| 2021 Convertible Notes [Member] \| Senior Notes [Member]
Schedule Of Description Of Business [Line Items]
Aggregate principal amount			$ 52,000,000
Convertible senior notes, interest rate, stated percentage			5.75%
Maximum [Member] \| Cowen and Company, LLC [Member]
Schedule Of Description Of Business [Line Items]
Amount of stock transactions					$ 200,000,000
Amount of common stock transactions					$ 50,000,000

Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) Segment	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Summary Of Significant Accounting Policy [Line Items]
Number of operating segments \| Segment			1
Realized gains or losses on short-term investment	$ 0	$ 0	$ 0	$ 0
Unrealized gains (losses) on short-term investment	0	$ 17,000	(18,000)	$ 28,000
Other than temporary impairment evaluated	0		0		$ 0
Share based compensation forfeiture rate prior to adoption					0.00%
2021 Convertible Notes [Member] \| Senior Notes [Member]
Summary Of Significant Accounting Policy [Line Items]
Amortization of debt issuance costs	$ 143,000		$ 282,000

Significant Accounting Policies - Schedule of Short-term Investment (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Cost Basis	$ 81,216	$ 96,729
Available-for-sale securities, Unrealized Gains		1
Available-for-sale securities, Unrealized Losses	(72)	(55)
Available-for-sale securities, Fair Value	81,144	96,675
Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Cost Basis	17,039	22,046
Available-for-sale securities, Fair Value	17,039	22,046
Agency Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Cost Basis	5,915	5,917
Available-for-sale securities, Unrealized Losses	(3)	(4)
Available-for-sale securities, Fair Value	5,912	5,913
United States Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Cost Basis	58,262	68,766
Available-for-sale securities, Unrealized Gains		1
Available-for-sale securities, Unrealized Losses	(69)	(51)
Available-for-sale securities, Fair Value	$ 58,193	$ 68,716

Significant Accounting Policies - Schedule of Computation of Basic and Diluted EPS (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Numerator:
Net loss applicable to common stockholders	$ (6,562)	$ (8,684)	$ (17,232)	$ (18,752)
Denominator:
Weighted average common shares outstanding - basic and diluted	26,994,454	26,623,280	26,990,409	26,523,337
Net loss per share applicable to common stockholders - basic and diluted	$ (0.24)	$ (0.33)	$ (0.64)	$ (0.71)

Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	10,439,050	2,594,728	10,439,050	2,594,728
Shares Issuable Upon Conversion of the 2021 Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	6,483,791		6,483,791
Warrants Exerciseable for Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	56,408	56,408	56,408	56,408
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	2,586,351	2,538,320	2,586,351	2,538,320
Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	1,312,500		1,312,500

Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 1,414	$ 1,561
Less: accumulated depreciation	(338)	(431)
Property and equipment, net	$ 1,076	1,130
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Useful lives	5 years
Property and equipment, Gross	$ 357	407
Computer Hardware and Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 96	263
Computer Hardware and Software [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Useful lives	3 years
Computer Hardware and Software [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Useful lives	7 years
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Useful lives	5 years
Property and equipment, Gross	$ 516	446
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Useful lives	7 years
Property and equipment, Gross	$ 445	$ 445

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Property Plant And Equipment Net [Abstract]
Depreciation expense	$ 63	$ 36	$ 124	$ 72
Amount written off on fully depreciated net assets	$ 217		$ 217

Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Payables And Accruals [Abstract]
Compensation and benefits	$ 1,098	$ 2,171
Research and development	367	1,148
Government payable	492	478
Professional fees	208	311
Other	258	308
Total	$ 2,423	$ 4,416

Debt - 2021 Convertible Notes - Additional Information (Detail)	3 Months Ended	6 Months Ended
	Jun. 30, 2017 USD ($) $ / shares	Jun. 30, 2017 USD ($) d $ / shares	Aug. 30, 2016 USD ($)	Aug. 05, 2016 USD ($)
Debt Instrument [Line Items]
Interest expense	$ 889,000	$ 1,765,000
2021 Convertible Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument principal amount				$ 50,000,000
Debt instrument maturity date		Aug. 01, 2021
Debt instrument payment terms		Semi-annually
Convertible senior notes, interest rate, stated percentage	5.75%	5.75%
Debt instrument payment start date		Feb. 01, 2017
Debt issuance costs incurred		$ 3,262,000
Number of shares, note gets converted into		124.7505
Principal amount	$ 1,000	$ 1,000
Debt instrument redemption description		The Company, at its option, may redeem for cash all or any portion of the 2021 Convertible Notes if the last reported sale price of a share of the Company’s common stock is equal to or greater than 200% of the conversion price for the 2021 Convertible Notes then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period (including the last trading day of such period) ending within the five trading days immediately preceding the date on which the Company provides notice of redemption, at a redemption price equal to 100% of the principal amount of the 2021 Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date.
Percentage of common stock conversion price		200.00%
Number of minimum trading days \| d		20
Number of consecutive trading days \| d		30
Holdings in debt outstanding		25.00%
Number of days after default		180 days
Effective interest rate	7.30%	7.30%
Interest expense	$ 889,000	$ 1,765,000
Amortization of debt discount	$ 143,000	$ 282,000
2021 Convertible Notes [Member] \| Senior Notes [Member] \| First 90 Days [Member]
Debt Instrument [Line Items]
Effective interest rate	0.25%	0.25%
2021 Convertible Notes [Member] \| Senior Notes [Member] \| 91 to 180 Days [Member]
Debt Instrument [Line Items]
Effective interest rate	0.50%	0.50%
2021 Convertible Notes [Member] \| Senior Notes [Member] \| Over-Allotment Option [Member]
Debt Instrument [Line Items]
Debt instrument principal amount			$ 2,000,000
2021 Convertible Notes [Member] \| Fundamental Change [Member]
Debt Instrument [Line Items]
Principal amount	$ 1,000	$ 1,000
Conversion of stock, description		If the Stock Price applicable to any conversion is greater than $40.00 per share, the Conversion Rate will not be increased. If the Stock Price applicable to any conversion is less than $6.68 per share, the Conversion Rate in connection with a Make-Whole Fundamental Change Conversion will not be increased but it will be increased by 24.95 shares in connection with a Voluntary Conversion.
Debt instrument repurchase description		Upon the occurrence of a Fundamental Change, the occurrence of certain change of control transactions or delisting events (as defined in the Indenture), each Holder may require the Company to repurchase for cash all or any portion of the 2021 Convertible Notes held by such Holder at a repurchase price equal to 100% of the principal amount thereof, plus accrued and unpaid interest thereon.
Percentage of principal amount of notes to be purchased		100.00%
2021 Convertible Notes [Member] \| Fundamental Change [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Number of shares, note gets converted into		0
Debt Instrument, conversion rate \| $ / shares	$ 40.00	$ 40.00
2021 Convertible Notes [Member] \| Fundamental Change [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Number of shares, note gets converted into		24.95
Debt Instrument, conversion rate \| $ / shares	$ 6.68	$ 6.68

Debt - Summary of Carrying Value of Convertible Notes (Detail) - 2021 Convertible Notes [Member] - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Carrying value	$ 49,242	$ 48,960
Senior Notes [Member]
Debt Instrument [Line Items]
Gross proceeds	52,000
Initial value of issuance costs recorded as debt discount	(3,262)
Amortization of debt discount	504
Carrying value	$ 49,242

Equity - Additional Information (Detail)		1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
Equity - Additional Information (Detail)	May 31, 2017 USD ($) shares	Jan. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) Milestone $ / shares shares	Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) Plan $ / shares shares	Jun. 30, 2016 USD ($)	Dec. 31, 2016 $ / shares shares	Jan. 01, 2017 shares
Stockholders Equity [Line Items]
Common stock, shares authorized			120,000,000	120,000,000		120,000,000		120,000,000
Common stock, par value \| $ / shares			$ 0.01	$ 0.01		$ 0.01		$ 0.01
Preferred stock, shares authorized			5,000,000	5,000,000		5,000,000		5,000,000
Preferred stock, par value \| $ / shares			$ 0.001	$ 0.001		$ 0.001		$ 0.001
Common stock voting rights description						one vote per share
Common stock, shares outstanding			26,986,318	27,010,202		27,010,202		26,986,318
Number of equity compensation plans \| Plan						3
Stock-based compensation expense \| $				$ 793,000	$ 686,000	$ 1,577,000	$ 1,173,000
Restricted Stock Units [Member]
Stockholders Equity [Line Items]
Vesting period		4 years
2014 Stock Option and Incentive Plan [Member]
Stockholders Equity [Line Items]
Number of shares reserved for future issuance				326,812		326,812			1,079,453
Percentage of outstanding common stock increased to shares available for grant								4.00%
Weighted-average fair value of stock option granted \| $ / shares				$ 1.80		$ 1.80
Closing price of common stock \| $ / shares				$ 1.90		$ 1.90
Stock options, intrinsic value \| $				$ 31,500,000		$ 31,500,000
2014 Stock Option and Incentive Plan [Member] \| Restricted Stock Units [Member]
Stockholders Equity [Line Items]
Number of shares granted by board						931,000
Number of common stock received for contingent right			1
Stock options, terms of vesting						Vesting for these RSU’s was based equally on the achievement of two performance-based conditions, subject to continued service through such achievement dates.
Number of vesting achievement of performance-based conditions \| Milestone			2
Intrinsic fair value, date of grant \| $			$ 3,055
Stock-based compensation expense \| $			$ 0
Fair value of grants to be recognized due to change in vesting criteria \| $		$ 717,000
Weighted average grant date fair value per share as of date of modification \| $ / shares				$ 1.53		$ 1.53
2014 Stock Option and Incentive Plan [Member] \| Restricted Stock Units [Member] \| Executive Officers [Member]
Stockholders Equity [Line Items]
Number of shares granted by board			470,000
2004 Stock Option Plan [Member]
Stockholders Equity [Line Items]
Closing price of common stock \| $ / shares				$ 1.90		$ 1.90
Stock options, intrinsic value \| $				$ 0		$ 0
Employee Stock Purchase Plan [Member]
Stockholders Equity [Line Items]
Number of shares reserved for future issuance				600,000		600,000			31,555
Percentage of outstanding common stock increased to shares available for grant						1.00%
Stock-based compensation expense \| $				$ 0	$ 0	$ 25,000	20,000
Number of shares available for issuance				245,979		245,979
Stock purchased under ESPP	23,884
Gross proceeds from issuance of common stock \| $	$ 35,000					$ 35,000	$ 45,000

Equity - Summary of Stock Option Activity (Detail)	6 Months Ended
Equity - Summary of Stock Option Activity (Detail)	Jun. 30, 2017 USD ($) $ / shares shares
2014 Stock Option and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Outstanding, Beginning Balance \| shares	2,664,832
Number of Shares , Granted \| shares	315,000
Number of Shares , Cancelled \| shares	(401,826)
Number of Shares Outstanding, Ending Balance \| shares	2,578,006
Number of Shares, Exercisable \| shares	1,279,252
Weighted-average years remaining on contractual life	8 years 3 months 8 days
Unrecognized compensation cost related to non-vested stock options \| $	$ 6,108,000
Weighted Average Exercise Price Per Share, Beginning Balance \| $ / shares	$ 6.16
Weighted Average Exercise Price Per Share, Granted \| $ / shares	1.80
Weighted Average Exercise Price Per Share, Cancelled \| $ / shares	6.95
Weighted Average Exercise Price Per Share, Ending Balance \| $ / shares	5.50
Weighted Average Exercise Price Per Share, Exercisable \| $ / shares	$ 5.57
Aggregate Intrinsic Value, Outstanding Ending Balance \| $	$ 31,500,000
2004 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Outstanding, Beginning Balance \| shares	10,626
Number of Shares, Expired \| shares	(2,281)
Number of Shares Outstanding, Ending Balance \| shares	8,345
Number of Shares, Exercisable \| shares	8,345
Weighted-average years remaining on contractual life	1 year 11 days
Weighted Average Exercise Price Per Share, Beginning Balance \| $ / shares	$ 40.58
Weighted Average Exercise Price Per Share, Expired \| $ / shares	40.58
Weighted Average Exercise Price Per Share, Ending Balance \| $ / shares	40.58
Weighted Average Exercise Price Per Share, Exercisable \| $ / shares	$ 40.58
Aggregate Intrinsic Value, Outstanding Ending Balance \| $	$ 0

Equity - Summary of RSU Activity (Detail) - Restricted Stock Units [Member] - 2014 Stock Option and Incentive Plan [Member]	6 Months Ended
	Jun. 30, 2017 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding, Beginning Balance \| shares	470,000
Number of Shares, Granted \| shares	931,000
Number of Shares, Cancelled \| shares	(88,500)
Number of Shares, Outstanding, Ending Balance \| shares	1,312,500
Weighted Average Grant Date Fair Value Per Share, Beginning Balance \| $ / shares	$ 6.50
Weighted Average Grant Date Fair Value Per Share, Granted \| $ / shares	1.60
Weighted Average Grant Date Fair Value Per Share, Cancelled \| $ / shares	1.70
Weighted Average Grant Date Fair Value Per Share, Ending Balance \| $ / shares	$ 1.57

Equity - Schedule of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 793	$ 686	$ 1,577	$ 1,173
Research and Development [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	292	316	595	525
General and Administrative [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 501	$ 370	$ 982	$ 648

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Operating Leased Assets [Line Items]
Acquisition of leasehold improvements						$ 445
Lease term					90 months
Lease extension term					5 years
Lease description			The lease term is 90 months and the Company has the right to extend the term for one period of five years
Operating leases, rent expenses	$ 84	$ 62	$ 169	$ 124
Whitehead v. Inotek Pharmaceuticals Corporation [Member] \| Pending Litigation [Member]
Operating Leased Assets [Line Items]
Lawsuit filing date			January 6, 2017
Amended complaint filing date			July 10, 2017
Name of plaintiff			purported stockholder of the Company
Lawsuit action domicile			U.S. District Court for the District of Massachusetts
Name of defendant			David Southwell, and Rudolf Baumgartner
Lawsuit allegation, description			The amended complaint alleges violations of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and SEC Rule 10b-5 against the Company, David Southwell, and Rudolf Baumgartner based on allegedly false and misleading statements and omissions regarding our phase 2 and phase 3 clinical trials of trabodenoson.
Lawsuit management action, description			The lawsuit seeks among other things, unspecified compensatory damages for purchasers of the Company’s common stock between July 23, 2015 and December 30, 2016, as well as interest and attorneys’ fees and costs. The Company intends to vigorously defend itself against this claim.

Commitments and Contingencies - Schedule of Aggregate Annual Commitments Pursuant to Office Lease and Lease Amendment (Detail) $ in Thousands	Jun. 30, 2017 USD ($)
Commitments And Contingencies Disclosure [Abstract]
2017	$ 202
2018	411
2019	421
2020	430
2021	439
Thereafter	520
Total	$ 2,423

Fair Value of Financial Measurements - Fair Value of Assets and Liabilities Measured on Recurring Basis (Detail) - Fair Value Measurements, Recurring [Member] - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Money Market Mutual Funds [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Money market mutual funds (included in cash and cash equivalents)	$ 21,581	$ 20,698
Money Market Mutual Funds [Member] \| Level 1 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Money market mutual funds (included in cash and cash equivalents)	21,581	20,698
Certificates of Deposit [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	17,039	22,046
Certificates of Deposit [Member] \| Level 2 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	17,039	22,046
Agency Bonds [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	5,912	5,913
Agency Bonds [Member] \| Level 2 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	5,912	5,913
United States Treasury Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	58,193	68,716
United States Treasury Securities [Member] \| Level 1 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	58,193	68,716
Short-term Investments [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	81,144	96,675
Short-term Investments [Member] \| Level 1 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	58,193	68,716
Short-term Investments [Member] \| Level 2 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Short-term investments fair value disclosure	$ 22,951	$ 27,959

Subsequent Event - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Subsequent Event [Line Items]
Equipment, net book value	$ 1,076	$ 1,130
Trabodenoson [Member] \| Equipment [Member]
Subsequent Event [Line Items]
Equipment, net book value	$ 437