Ocera Therapeutics 10-Q 4 Aug 16 2016 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2016	Jul. 29, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	Ocera Therapeutics, Inc.
Entity Central Index Key	1,274,644
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		21,851,488

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 34,193	$ 35,921
Short-term investments, available-for-sale	1,250	7,415
Prepaid expenses and other current assets	466	686
Total current assets	35,909	44,022
Property and equipment, net	69	94
Deposits	36	26
Goodwill	595	595
Total assets	36,609	44,737
Current liabilities:
Accounts payable	1,435	701
Accrued liabilities	3,529	3,133
Notes payable - short term	1,021	0
Total current liabilities	5,985	3,834
Notes payable - long term	8,582	9,508
Other liabilities	102	1
Total liabilities	14,669	13,343
Stockholders' equity:
Preferred stock - $0.00001 par value, 5,000,000 shares authorized and no shares issued or outstanding.	0	0
Common stock - $0.00001 par value, 100,000,000 shares authorized, 21,839,519 issued and outstanding at June 30, 2016 and 20,695,160 shares issued and outstanding at December 31, 2015.	0	0
Additional paid-in capital	167,990	162,832
Accumulated other comprehensive loss	0	(5)
Accumulated deficit	(146,050)	(131,433)
Total stockholders' equity	21,940	31,394
Total liabilities and stockholders' equity	$ 36,609	$ 44,737

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Preferred stock, par value (in usd per share)	$ 0.00001	$ 0.00001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in usd per share)	$ 0.00001	$ 0.00001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	21,839,519	20,695,160
Common stock, shares, outstanding (in shares)	21,839,519	20,695,160

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Royalty revenue	$ 26	$ 43	$ 59	$ 74
Operating expenses:
Research and development	3,909	3,417	8,656	7,815
General and administrative	2,970	2,832	5,524	5,088
Amortization of intangibles	0	41	0	82
Total operating expenses	6,879	6,290	14,180	12,985
Other (expense) income:
Interest and other income	30	26	63	49
Interest and other expense	(280)	0	(559)	(10)
Other (expense) income, net	(250)	26	(496)	39
Net loss	$ (7,103)	$ (6,221)	$ (14,617)	$ (12,872)
Net loss per share:
Net loss per share, basic and diluted (in usd per share)	$ (0.33)	$ (0.31)	$ (0.69)	$ (0.65)
Weighted average number of shares used to compute net loss per share of common stock, basic and diluted (in shares)	21,552,089	19,772,345	21,248,027	19,759,923
Comprehensive loss:
Net loss	$ (7,103)	$ (6,221)	$ (14,617)	$ (12,872)
Unrealized (loss) gain on investments	(1)	(2)	5	26
Comprehensive loss	$ (7,104)	$ (6,223)	$ (14,612)	$ (12,846)

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Statement of Cash Flows [Abstract]
Net loss	$ (14,617)	$ (12,872)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	25	16
Amortization of intangibles	0	82
Stock-based compensation	2,165	1,902
Amortization of premium on marketable securities	40	253
Amortization of debt discount	95	0
Changes in operating assets and liabilities:
Prepaid expenses and other assets	210	273
Accounts payable	734	134
Accrued and other liabilities	497	64
Net cash used in operating activities	(10,851)	(10,148)
Investing activities
Purchases of marketable securities	(3,754)	(18,022)
Proceeds from maturities of marketable securities	9,884	26,000
Net cash provided by investing activities	6,130	7,978
Financing activities
Proceeds from sale of common stock, net of underwriting discounts and issuance cost	2,982	413
Proceeds from exercise of common stock options	11	0
Net cash provided by financing activities	2,993	413
Net decrease in cash and cash equivalents	(1,728)	(1,757)
Cash and cash equivalents—beginning of period	35,921	10,127
Cash and cash equivalents—end of period	34,193	8,370
Supplemental disclosures of cash flow information
Cash paid for interest	414	0
Noncash Investing and Financing Items [Abstract]
Issuance cost related to at the market equity program in accounts payable	$ 0	$ 9

The Company

The Company	6 Months Ended
	Jun. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	The Company Ocera Therapeutics, Inc. (the "Company") is a clinical-stage biopharmaceutical company focused on the development and commercialization of OCR-002 (ornithine phenylacetate). OCR-002 is an ammonia scavenger which has been granted orphan drug designation and Fast Track status by the U.S. Food and Drug Administration for the treatment of hyperammonemia and resultant hepatic encephalopathy in patients with liver cirrhosis, acute liver failure and acute-on-chronic liver disease. On July 15, 2013, Terrapin Acquisition, Inc., a Delaware corporation (“Merger Sub”), a wholly owned subsidiary of Tranzyme, Inc., a Delaware corporation (“Tranzyme”), completed its merger (the “Merger”) with and into Ocera Therapeutics, Inc., a private Delaware corporation (“Private Ocera”). Private Ocera was considered the acquiring company in the Merger for accounting purposes. In connection with the Merger, the combined company changed its name to Ocera Therapeutics, Inc. and the name of Private Ocera was changed to Ocera Subsidiary, Inc. (“Ocera Subsidiary”). The Company's business is subject to significant risks consistent with biopharmaceutical companies seeking to develop technologies and product candidates for human therapeutic use. These risks include, but are not limited to, uncertainties regarding research and development, access to capital, obtaining and enforcing patents, receiving regulatory approval and competition with other biotechnology and pharmaceutical companies. The Company has a limited operating history and the sales and income potential of the Company's business and market are unproven. As of June 30, 2016 , the Company has incurred losses since inception of $ 146.1 million . The Company anticipates that it will continue to incur net losses into the foreseeable future as it continues its efforts to develop and commercialize OCR-002 and as it expands its corporate infrastructure. Based on the Company's current operating plan, the Company believes its working capital is sufficient to fund its operations through at least the next twelve months.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company and our wholly-owned subsidiary have been prepared in accordance with United States of America generally accepted accounting principles ("U.S. GAAP") for interim financial statements and pursuant to the rules and regulations of the Securities and Exchange Commission. For interim reporting the financial statements and related notes do not include all information and footnotes required by U.S. GAAP for annual reports. Accordingly, the accompanying unaudited interim condensed consolidated financial statements were derived from audited condensed financial statements, but do not include all disclosures required by U.S. GAAP for complete financial statements. This quarterly report should be read in conjunction with the consolidated financial statements included in the Company’s annual report on Form 10-K for the year ended December 31, 2015. Unaudited Interim Financial Information The accompanying interim condensed consolidated financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented. The consolidated results of operations for any interim period are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period. Use of Estimates The preparation of financial statements in conformity with the U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. Investments in Marketable Securities All investments in marketable securities have been classified as "available-for-sale" and are carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities. Unrealized gains and losses are excluded from earnings and are reported as a component of accumulated comprehensive income. Realized gains and losses and declines in fair value judged to be other than temporary, if any, on investments in marketable securities are included in interest and other income (expense), net. The cost of securities sold is based on the specific-identification method. Interest earned on investments in marketable securities is included in interest and other income. Recent Accounting Pronouncements Occasionally, new accounting standards are issued or proposed by the Financial Accounting Standards Board (the "FASB"), or other standards-setting bodies that the Company adopts by the effective date specified within the standard. Unless otherwise discussed, standards that do not require adoption until a future date are not expected to have a material impact on the Company's condensed consolidated financial statements upon adoption. Recent Accounting Updates Not Yet Effective In February 2016, the FASB issued Accounting Standards Update, or ASU 2016-02, Leases, to increase transparency and comparability among organizations by requiring recognition of lease assets and lease liabilities on the balance sheet and disclosure of key information about leasing arrangements. The standard will become effective for interim and annual periods beginning after December 15, 2018, with early adoption permitted. The guidance is required to be adopted at the earliest period presented using a modified retrospective approach. The Company is currently evaluating the impact of the adoption of this standard on our condensed consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update, or ASU 2016-06, Derivatives and Hedging (Topic 815), Contingent Put and Call Options in Debt Instruments. This ASU clarifies the requirements for assessing whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. An entity performing the assessment under the amendments in this ASU is required to assess the embedded call (put) options solely in accordance with the four-step decision sequence. The new standard simplifies the embedded derivative analysis for debt instruments containing contingent call or put options by removing the requirement to assess whether a contingent event is related to interest rates or credit risks. This guidance should be applied on a modified retrospective basis to existing debt instruments as of the beginning of the fiscal year in which the amendments are effective, and is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The Company is currently evaluating the impact that the adoption of this standard will have on its condensed consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update, or ASU 2016-09, Improvements to Employee Share-Based Payment Accounting (Topic 718), Compensation - Stock Compensation. The new guidance simplifies several aspects of the accounting for share-based payments, including immediate recognition of all excess tax benefits and deficiencies in the income statement, changing the threshold to qualify for equity classification up to the employees' maximum statutory tax rates, allowing an entity-wide accounting policy election to either estimate the number of awards that are expected to vest or account for forfeitures as they occur, and clarifying the classification on the statement of cash flows for the excess tax benefit and employee taxes paid when an employer withholds shares for tax-withholding purposes. ASU 2016-09 is effective for annual reporting periods beginning after December 15, 2016, and interim periods within that reporting period. The Company is currently evaluating the impact that the adoption of this standard will have on its condensed consolidated financial statements. In May 2014, the FASB issued Accounting Standard Accounting Standards Update, or ASU, No. 2014-09, Revenue from Contracts with Customers. The standard’s core principle is that a reporting entity will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard will become effective for the Company beginning in the first quarter of 2018. Early adoption is permitted in 2017. Entities have the option of using either a full retrospective or a modified retrospective approach to adopt this new guidance. In March and April 2016, the FASB issued ASU, No. 2016-08 Revenue From Contracts With Customers : Principal vs. Agent Considerations and ASU 2016-10 Revenue From Contracts with Customers: Identifying Performance Obligations and Licensing to provide supplemental adoption guidance and clarification to ASU 2014-09. The Company is currently evaluating the impact of the adoption of these standards on their Condensed Consolidated Financial Statements.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Financial assets and liabilities are recorded at fair value. The carrying amounts of certain of our financial instruments, including cash and cash equivalents, prepaid expenses and other current assets, accounts payable, and accrued liabilities and deferred revenue, approximate their fair value due to their short maturities. Short-term and long-term debt are reported at their respective amortized cost on our Consolidated Balance Sheets. The remaining financial instruments are reported on our Consolidated Balance Sheets at amounts that approximate current fair values. The following tables present information about the Company’s financial assets measured at fair value on a recurring basis as of June 30, 2016 , and December 31, 2015, and indicate the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair value. As a basis for categorizing inputs, the Company uses a three-tier fair value hierarchy, which prioritizes the inputs used to measure fair value from market-based assumptions to entity specific assumptions: Level 1: Inputs which include quoted prices in active markets for identical assets or liabilities; Level 2: Inputs, other than level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and Level 3: Unobservable inputs that are supported by little or no market activity, which require the reporting entity to develop its own assumptions. None of the Company’s non-financial assets and liabilities are recorded at fair value on a non-recurring basis. No transfers between levels have occurred during the periods presented. Assets measured at fair value on a recurring basis as of June 30, 2016 are as follows (in thousands): Balance as of June 30, 2016 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Money market funds $ 34,406 $ 34,406 $ — $ — Corporate debt securities 1,250 — 1,250 — $ 35,656 $ 34,406 $ 1,250 $ — Assets measured at fair value on a recurring basis as of December 31, 2015 are as follows (in thousands): Balance as of December 31, 2015 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Money market funds $ 34,806 $ 34,806 $ — $ — Corporate debt securities 7,415 — 7,415 — $ 42,221 $ 34,806 $ 7,415 $ — The Company estimates the fair value of corporate debt securities by taking into consideration valuations obtained from third-party pricing services. The pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker quotes on the same or similar securities; issuer credit spreads; benchmark securities; prepayment or default projections based on historical data; and other observable inputs. The estimated fair value of the Company's notes payable, considering level 2 inputs, approximates their carrying value based upon the borrowing terms and conditions currently available to the Company.

Balance Sheet Components

Balance Sheet Components	6 Months Ended
	Jun. 30, 2016
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Components	Balance Sheet Components Investments in Marketable Securities The following table summarizes the Company's available for sale investments as of June 30, 2016 (in thousands): Maturity (in Years) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Short-term investments: Corporate debt securities 1 or less 1,250 — — 1,250 Total short-term investments $ 1,250 $ — $ — $ 1,250 The following table summarizes the Company's available for sale investments as of December 31, 2015 (in thousands): Maturity (in Years) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Short-term investments: Corporate debt securities 1 or less $ 7,420 $ — $ (5 ) $ 7,415 Total short-term investments $ 7,420 $ — $ (5 ) $ 7,415 At each reporting date, the Company reviews its investments for impairment to determine if unrealized losses are other-than-temporary. For debt securities, management determines whether it intends to sell the impaired securities, and if there is no intent or expected requirement to sell, management considers whether it is likely that the amortized cost will be recovered. The Company does not consider unrealized losses on its debt investment securities to be credit-related. These unrealized losses relate to changes in interest rates and market spreads subsequent to purchase. The Company has not made a decision to sell securities with unrealized losses and believes it is more likely than not that it would not be required to sell such securities before recovery of its amortized cost. There have been no other-than-temporary losses recognized in earnings in any of the periods presented. Accrued Liabilities Accrued liabilities were as follows (in thousands): June 30, December 31, 2016 2015 Clinical trials $ 2,234 $ 1,666 Compensation and related expenses 782 993 Professional services 414 319 Interest expense 69 110 Other 30 45 Total accrued liabilities $ 3,529 $ 3,133

Notes Payable

Notes Payable	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Notes Payable	Notes Payable On July 30, 2015, the Company and Ocera Subsidiary entered into a Loan and Security Agreement (the “Loan Agreement”) with Oxford Finance LLC (“Oxford”) and Silicon Valley Bank (“SVB”) (collectively, the “Lenders”). The Loan Agreement provides for up to $20.0 million in new term loans (the “Term Loan Facility”), $ 10.0 million of which was funded on July 30, 2015. The remaining $10.0 million is available for draw until December 31, 2016 at the Company’s discretion, subject to achievement of certain financial and clinical milestones. The milestones will be satisfied if the Company (a) has raised proceeds of at least $15.0 million from the sale of equity securities or upfront payments from a partnership agreement and (b) achieved positive data from its ongoing Phase 2b clinical trial of OCR-002. The annual interest rate for the initial $10.0 million funding is 8.275% , and the interest rate for the second tranche will be fixed upon drawdown at an annual rate that is greater of 8.275% or 8.085% plus the 30-day U.S. LIBOR rate. Loan payments are interest-only until February 1, 2017, followed by 30 equal monthly payments of principal and interest through the scheduled maturity date of August 1, 2019 if the second tranche is not drawn. If the second tranche is drawn, the interest-only period continues to August 1, 2017, followed by 24 equal monthly payments. In addition, a final payment equal to 3% of the aggregate amount drawn will be due at maturity or on earlier repayment. If the Company prepays all or a portion of the loans, a prepayment fee of between 1% - 3 % of the principal amount prepaid will also be due depending on the timing of the prepayment. At the initial funding, the Company received net proceeds of $9.7 million after fees and expenses. These fees and expenses are being accounted for as a debt discount and classified within notes payable on the Company’s condensed consolidated balance sheet. Legal and consulting fees are presented in the condensed consolidated balance sheet as a direct deduction from the carrying amount of the notes liability, consistent with debt discounts. Debt discounts, issuance costs and the final payment are being amortized or accreted as interest expense over the term of the loan using the effective interest method. In connection with the Loan Agreement, the Company issued the Lenders warrants to purchase an aggregate of 97,680 shares of the Company's common stock at an exercise price of $4.095 per share. The Company recorded $0.3 million for the warrants as debt discount within notes payable and an increase to additional paid-in capital on the Company’s condensed consolidated balance sheet. As of June 30, 2016, the warrants remained outstanding and exercisable. The debt discount is being amortized as interest expense over the term of the Term Loan Facility using the effective interest method. The Term Loan Facility is secured by substantially all of the assets of the Company and its subsidiaries, except that the collateral does not include any intellectual property held by the Company or its subsidiary. However, the Company has agreed not to encumber any of the intellectual property of the Company or its subsidiary. The Loan Agreement contains customary representations, warranties and covenants by the Company, and customary indemnification obligations and events of default. The Company was in compliance with all covenants set forth in the Loan Agreement as of June 30, 2016 . The Company recorded interest expense related to the Term Loan Facility of $0.3 million for the three months ended June 30, 2016 , and $0.6 million for the six months ended June 30, 2016 . The annual effective interest rate on the note payable, including the amortization of the debt discounts and accretion of the final payments, is 11.72% . Future minimum payments under the Loan Agreement as of June 30, 2016 are as follows ( in thousands): Years ending December 31: 2016 (Remaining Six Months) $ 414 2017 3,839 2018 4,442 2019 3,261 Total future minimum payments 11,956 Less amount representing interest 1,956 Notes payable, gross 10,000 Unamortized discount on notes payable (397 ) Notes payable, balance 9,603 Less current portion of notes payable 1,021 Non-current portion of notes payable $ 8,582

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2016
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity On May 15, 2015, the Company entered into a sales agreement (the “Sales Agreement”) with Cowen and Company, LLC (“Cowen”), pursuant to which the Company may issue and sell shares of its common stock having aggregate sales proceeds of up to $25.0 million from time to time through an “at the market” equity program under which Cowen acts as sales agent. During the six months ended June 30, 2016 , the Company sold an aggregate of 1,132,390 shares of common stock under the Sales Agreement, at an average price of approximately $2.77 per share, for gross proceeds of $3.1 million and net proceeds of $3.0 million after deducting commissions and other transactions costs. During the six months ended June 30, 2015, the Company sold 135,562 shares of common stock under the Sales Agreement, at an average price of approximately $3.79 per share for gross proceeds of $0.5 million and net proceeds of $0.4 million after deducting commissions and other transactions costs. As of June 30, 2016 , $18.1 million of common stock remained available to be sold under the Sales Agreement, subject to certain conditions specified therein.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Company’s stock option activity and related information for the six months ended June 30, 2016 was as follows (in thousands, except share and per share data): Weighted-avg. Shares Weighted-avg. Remaining Aggregate Available Stock Options Exercise Price Contractual Intrinsic for Grant Outstanding Per Share Life (in Years) Value Balance at December 31, 2015 1,299,301 2,429,511 $ 7.00 8.01 $ 287 Additional shares authorized 1,400,000 Stock options granted (1,537,000 ) 1,537,000 $ 2.94 Stock options canceled 220,978 (220,978 ) $ 6.98 Stock options exercised — (11,969 ) $ 0.92 Balance at June 30, 2016 1,383,279 3,733,564 $ 5.35 8.26 $ 105 At June 30, 2016: Vested and expected to vest 3,595,695 $ 5.41 8.22 $ 105 Exercisable 1,381,095 $ 7.50 7.50 $ 105 The aggregate intrinsic value of options exercised under all option plans was $25,000 for the six months ended June 30, 2016 determined as of the date of option exercise. No options were exercised during the six months ended June 30, 2015. The Company recognized stock-based compensation expense within the condensed consolidated statements of operations and comprehensive loss as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Research and development $ 171 $ 56 $ 377 $ 265 General and administrative 888 881 1,788 1,637 Total $ 1,059 $ 937 $ 2,165 $ 1,902 The above table includes stock compensation expense for consultants of $9 ,000 and $19,000 for the three and six months ended June 30, 2016, respectively. Stock compensation expense for consultants was insignificant for the three and six months ended June 30, 2015. At June 30, 2016 , there were 136,000 unvested options outstanding with performance conditions related to the achievement of certain clinical milestones. During the three and six months ended June 30, 2016 , no expense was recorded for the performance-based options as it was not yet probable that such milestones would be met. In April 2016, the Company’s board of directors approved an amendment and restatement of the Company’s Fourth Amended and Restated 2011 Stock Option and Incentive Plan (the “2011 Plan”) to, among other things, increase the maximum number of shares that may be issued under the 2011 Plan from 3,602,328 to 5,002,328 shares. The amendment and restatement of the 2011 Plan was approved by the Company’s stockholders on June 14, 2016 . As of June 30, 2016 , there was unrecognized stock compensation expense of $7.6 million related to stock options. The Company expects to recognize those costs over a weighted average period of 2.30 years. Stock-based compensation expense for stock options is estimated at the grant date based on the fair-value using the Black-Scholes option pricing model. The fair value of employee stock options is being amortized on a straight-line basis over the requisite service period of the awards. The fair value of all stock options granted was estimated using the following weighted-average assumptions: Three Months Ended Six Months Ended 2016 2015 2016 2015 Expected dividend yield — — — — Risk-free interest rates 1.25% -1.47% 1.65% - 2.08% 1.25% - 1.97% 1.52% - 2.08% Expected term in years 4.41 - 8.14 5.49 - 8.06 4.41 - 8.14 5.49 - 8.06 Expected volatility 74% - 94% 78% - 92% 74% - 94% 78% - 92% On January 6, 2016 , the Company granted certain of its executive officers non-qualified stock options to purchase 206,625 shares of the Company’s common stock that vest on a monthly basis in equal installments over 48 months following the grant date if the Company's stock price equals or exceeds $6.00 for 20 consecutive trading days on or before June 30, 2017 . The options expire ten years from the date of the grant. The weighted-average fair values of these options was determined using a Monte Carlo simulation model incorporating the following assumptions: Six Months Ended Expected dividend yield — Risk-free interest rates 1.82% - 2.05% Expected term in years 6.02 - 8.00 Expected volatility 77% - 89% Weighted-average fair value per share 1.33 - 1.42 The estimated expense for these awards is being recognized on an accelerated basis over the estimated requisite service period, with no adjustments in the future periods based upon the Company's actual common stock price. The Company recorded $29,000 and $91,000 during the three months and six months ended June 30, 2016 , respectively, of share-based compensation expense in connection with the market condition stock option awards described above.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jun. 30, 2016
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing the net loss by the weighted average number of common shares and common share equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. Potentially dilutive securities which include warrants and outstanding stock options have been excluded from the computation of diluted net loss per share as the effect of their inclusion would be considered anti-dilutive. For all periods presented, there is no difference in the number of shares used to compute basic and diluted shares outstanding due to the Company’s net loss position. The following table presents the computation of net loss per share (in thousands, except share and per share data): Three Months Ended Six Months Ended 2016 2015 2016 2015 Numerator Net loss $ (7,103 ) $ (6,221 ) $ (14,617 ) $ (12,872 ) Denominator Weighted average common shares outstanding used to compute net loss per share, basic and diluted 21,552,089 19,772,345 21,248,027 19,759,923 Net loss per share of common stock, basic and diluted Net loss per share $ (0.33 ) $ (0.31 ) $ (0.69 ) $ (0.65 ) The following weighted average outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share of common stock for the periods presented as the effect of their inclusion would have been considered anti-dilutive: Three Months Ended Six Months Ended 2016 2015 2016 2015 Common stock warrants 1,026,249 931,942 1,026,249 932,237 Common stock options 3,681,401 2,020,872 3,655,965 2,029,911 Total 4,707,650 2,952,814 4,682,214 2,962,148

Summary of Significant Accoun14

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company and our wholly-owned subsidiary have been prepared in accordance with United States of America generally accepted accounting principles ("U.S. GAAP") for interim financial statements and pursuant to the rules and regulations of the Securities and Exchange Commission. For interim reporting the financial statements and related notes do not include all information and footnotes required by U.S. GAAP for annual reports. Accordingly, the accompanying unaudited interim condensed consolidated financial statements were derived from audited condensed financial statements, but do not include all disclosures required by U.S. GAAP for complete financial statements. This quarterly report should be read in conjunction with the consolidated financial statements included in the Company’s annual report on Form 10-K for the year ended December 31, 2015.
Consolidation	Unaudited Interim Financial Information The accompanying interim condensed consolidated financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented. The consolidated results of operations for any interim period are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with the U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.
Short-term investments	Investments in Marketable Securities All investments in marketable securities have been classified as "available-for-sale" and are carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities. Unrealized gains and losses are excluded from earnings and are reported as a component of accumulated comprehensive income. Realized gains and losses and declines in fair value judged to be other than temporary, if any, on investments in marketable securities are included in interest and other income (expense), net. The cost of securities sold is based on the specific-identification method. Interest earned on investments in marketable securities is included in interest and other income
New Accounting Pronouncements	Recent Accounting Pronouncements Occasionally, new accounting standards are issued or proposed by the Financial Accounting Standards Board (the "FASB"), or other standards-setting bodies that the Company adopts by the effective date specified within the standard. Unless otherwise discussed, standards that do not require adoption until a future date are not expected to have a material impact on the Company's condensed consolidated financial statements upon adoption. Recent Accounting Updates Not Yet Effective In February 2016, the FASB issued Accounting Standards Update, or ASU 2016-02, Leases, to increase transparency and comparability among organizations by requiring recognition of lease assets and lease liabilities on the balance sheet and disclosure of key information about leasing arrangements. The standard will become effective for interim and annual periods beginning after December 15, 2018, with early adoption permitted. The guidance is required to be adopted at the earliest period presented using a modified retrospective approach. The Company is currently evaluating the impact of the adoption of this standard on our condensed consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update, or ASU 2016-06, Derivatives and Hedging (Topic 815), Contingent Put and Call Options in Debt Instruments. This ASU clarifies the requirements for assessing whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. An entity performing the assessment under the amendments in this ASU is required to assess the embedded call (put) options solely in accordance with the four-step decision sequence. The new standard simplifies the embedded derivative analysis for debt instruments containing contingent call or put options by removing the requirement to assess whether a contingent event is related to interest rates or credit risks. This guidance should be applied on a modified retrospective basis to existing debt instruments as of the beginning of the fiscal year in which the amendments are effective, and is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The Company is currently evaluating the impact that the adoption of this standard will have on its condensed consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update, or ASU 2016-09, Improvements to Employee Share-Based Payment Accounting (Topic 718), Compensation - Stock Compensation. The new guidance simplifies several aspects of the accounting for share-based payments, including immediate recognition of all excess tax benefits and deficiencies in the income statement, changing the threshold to qualify for equity classification up to the employees' maximum statutory tax rates, allowing an entity-wide accounting policy election to either estimate the number of awards that are expected to vest or account for forfeitures as they occur, and clarifying the classification on the statement of cash flows for the excess tax benefit and employee taxes paid when an employer withholds shares for tax-withholding purposes. ASU 2016-09 is effective for annual reporting periods beginning after December 15, 2016, and interim periods within that reporting period. The Company is currently evaluating the impact that the adoption of this standard will have on its condensed consolidated financial statements. In May 2014, the FASB issued Accounting Standard Accounting Standards Update, or ASU, No. 2014-09, Revenue from Contracts with Customers. The standard’s core principle is that a reporting entity will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard will become effective for the Company beginning in the first quarter of 2018. Early adoption is permitted in 2017. Entities have the option of using either a full retrospective or a modified retrospective approach to adopt this new guidance. In March and April 2016, the FASB issued ASU, No. 2016-08 Revenue From Contracts With Customers : Principal vs. Agent Considerations and ASU 2016-10 Revenue From Contracts with Customers: Identifying Performance Obligations and Licensing to provide supplemental adoption guidance and clarification to ASU 2014-09. The Company is currently evaluating the impact of the adoption of these standards on their Condensed Consolidated Financial Statements.
Earnings Per Share	Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing the net loss by the weighted average number of common shares and common share equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. Potentially dilutive securities which include warrants and outstanding stock options have been excluded from the computation of diluted net loss per share as the effect of their inclusion would be considered anti-dilutive. For all periods presented, there is no difference in the number of shares used to compute basic and diluted shares outstanding due to the Company’s net loss position.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	Assets measured at fair value on a recurring basis as of June 30, 2016 are as follows (in thousands): Balance as of June 30, 2016 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Money market funds $ 34,406 $ 34,406 $ — $ — Corporate debt securities 1,250 — 1,250 — $ 35,656 $ 34,406 $ 1,250 $ — Assets measured at fair value on a recurring basis as of December 31, 2015 are as follows (in thousands): Balance as of December 31, 2015 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Money market funds $ 34,806 $ 34,806 $ — $ — Corporate debt securities 7,415 — 7,415 — $ 42,221 $ 34,806 $ 7,415 $ —

Balance Sheet Components (Table

Balance Sheet Components (Tables)	6 Months Ended
	Jun. 30, 2016
Balance Sheet Related Disclosures [Abstract]
Available-for-sale Securities	The following table summarizes the Company's available for sale investments as of June 30, 2016 (in thousands): Maturity (in Years) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Short-term investments: Corporate debt securities 1 or less 1,250 — — 1,250 Total short-term investments $ 1,250 $ — $ — $ 1,250 The following table summarizes the Company's available for sale investments as of December 31, 2015 (in thousands): Maturity (in Years) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Short-term investments: Corporate debt securities 1 or less $ 7,420 $ — $ (5 ) $ 7,415 Total short-term investments $ 7,420 $ — $ (5 ) $ 7,415
Schedule of Accrued Liabilities	Accrued liabilities were as follows (in thousands): June 30, December 31, 2016 2015 Clinical trials $ 2,234 $ 1,666 Compensation and related expenses 782 993 Professional services 414 319 Interest expense 69 110 Other 30 45 Total accrued liabilities $ 3,529 $ 3,133

Notes Payable (Tables)

Notes Payable (Tables)	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Future minimum payments under the Loan Agreement as of June 30, 2016 are as follows ( in thousands): Years ending December 31: 2016 (Remaining Six Months) $ 414 2017 3,839 2018 4,442 2019 3,261 Total future minimum payments 11,956 Less amount representing interest 1,956 Notes payable, gross 10,000 Unamortized discount on notes payable (397 ) Notes payable, balance 9,603 Less current portion of notes payable 1,021 Non-current portion of notes payable $ 8,582

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of stock option activity	The Company’s stock option activity and related information for the six months ended June 30, 2016 was as follows (in thousands, except share and per share data): Weighted-avg. Shares Weighted-avg. Remaining Aggregate Available Stock Options Exercise Price Contractual Intrinsic for Grant Outstanding Per Share Life (in Years) Value Balance at December 31, 2015 1,299,301 2,429,511 $ 7.00 8.01 $ 287 Additional shares authorized 1,400,000 Stock options granted (1,537,000 ) 1,537,000 $ 2.94 Stock options canceled 220,978 (220,978 ) $ 6.98 Stock options exercised — (11,969 ) $ 0.92 Balance at June 30, 2016 1,383,279 3,733,564 $ 5.35 8.26 $ 105 At June 30, 2016: Vested and expected to vest 3,595,695 $ 5.41 8.22 $ 105 Exercisable 1,381,095 $ 7.50 7.50 $ 105
Stock-based compensation expense	The Company recognized stock-based compensation expense within the condensed consolidated statements of operations and comprehensive loss as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Research and development $ 171 $ 56 $ 377 $ 265 General and administrative 888 881 1,788 1,637 Total $ 1,059 $ 937 $ 2,165 $ 1,902
Stock option valuation assumptions	The weighted-average fair values of these options was determined using a Monte Carlo simulation model incorporating the following assumptions: Six Months Ended Expected dividend yield — Risk-free interest rates 1.82% - 2.05% Expected term in years 6.02 - 8.00 Expected volatility 77% - 89% Weighted-average fair value per share 1.33 - 1.42 The fair value of all stock options granted was estimated using the following weighted-average assumptions: Three Months Ended Six Months Ended 2016 2015 2016 2015 Expected dividend yield — — — — Risk-free interest rates 1.25% -1.47% 1.65% - 2.08% 1.25% - 1.97% 1.52% - 2.08% Expected term in years 4.41 - 8.14 5.49 - 8.06 4.41 - 8.14 5.49 - 8.06 Expected volatility 74% - 94% 78% - 92% 74% - 94% 78% - 92%

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	6 Months Ended
	Jun. 30, 2016
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table presents the computation of net loss per share (in thousands, except share and per share data): Three Months Ended Six Months Ended 2016 2015 2016 2015 Numerator Net loss $ (7,103 ) $ (6,221 ) $ (14,617 ) $ (12,872 ) Denominator Weighted average common shares outstanding used to compute net loss per share, basic and diluted 21,552,089 19,772,345 21,248,027 19,759,923 Net loss per share of common stock, basic and diluted Net loss per share $ (0.33 ) $ (0.31 ) $ (0.69 ) $ (0.65 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	Three Months Ended Six Months Ended 2016 2015 2016 2015 Common stock warrants 1,026,249 931,942 1,026,249 932,237 Common stock options 3,681,401 2,020,872 3,655,965 2,029,911 Total 4,707,650 2,952,814 4,682,214 2,962,148

The Company (Details)

The Company (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ (146,050)	$ (131,433)

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value) (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$ 35,656	$ 42,221
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	34,406	34,806
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,250	7,415
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	34,406	34,806
Money market funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	34,406	34,806
Money market funds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Money market funds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,250	7,415
Corporate debt securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Corporate debt securities | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,250	7,415
Corporate debt securities | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$ 0	$ 0

Balance Sheet Components (Avail

Balance Sheet Components (Available For Sale Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 1,250
Unrealized Gains	0
Unrealized Losses	0
Estimated Fair Value	1,250
Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		$ 7,420
Unrealized Gains		0
Unrealized Losses		(5)
Estimated Fair Value		7,415
Short-term Investments | Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,250	7,420
Unrealized Gains	0	0
Unrealized Losses	0	(5)
Estimated Fair Value	$ 1,250	$ 7,415

Balance Sheet Components (Accru

Balance Sheet Components (Accrued Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Balance Sheet Related Disclosures [Abstract]
Clinical trials	$ 2,234	$ 1,666
Compensation and related expenses	782	993
Professional services	414	319
Interest expense	69	110
Other	30	45
Total accrued liabilities	$ 3,529	$ 3,133

Notes Payable (Narrative) (Deta

Notes Payable (Narrative) (Details) - USD ($)	Jul. 30, 2015	Jun. 30, 2016	Jun. 30, 2016
Oxford Finance LLC and Silicon Valley Bank
Debt Instrument [Line Items]
Interest expense		$ 300,000	$ 600,000
Effective interest rate (in percentage)		11.72%	11.72%
Notes Payable | Secured Debt | Oxford Finance LLC and Silicon Valley Bank
Debt Instrument [Line Items]
Debt instrument, maximum borrowing capacity	$ 20,000,000
Notes payable, gross	10,000,000	$ 10,000,000	$ 10,000,000
Remaining borrowing capacity	10,000,000
Proceeds from sale of equity	$ 15,000,000
Stated interest rate ( in percentage)	8.275%
Periodic payment terms, balloon payment to be paid, percentage of funded borrowings (in percentage)	3.00%
Proceeds from debt, net of issuance costs	$ 9,700,000
Notes Payable | Secured Debt | Oxford Finance LLC and Silicon Valley Bank | Minimum
Debt Instrument [Line Items]
Early extinguishment of debt, prepayment fee (in percentage)	1.00%
Notes Payable | Secured Debt | Oxford Finance LLC and Silicon Valley Bank | Maximum
Debt Instrument [Line Items]
Early extinguishment of debt, prepayment fee (in percentage)	3.00%
Notes Payable | Secured Debt | Oxford Finance LLC and Silicon Valley Bank | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percentage)	8.085%
Common stock warrants
Debt Instrument [Line Items]
Warrants issued (in shares)	97,680
Exercise price of warrants (usd per share)	$ 4.095
Warrants outstanding		$ 300,000	$ 300,000

Notes Payable (Schedule of Long

Notes Payable (Schedule of Long Term Debt Instruments) (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015	Jul. 30, 2015
Debt Instrument [Line Items]
Less amount representing interest	$ 69,000	$ 110,000
Oxford Finance LLC and Silicon Valley Bank | Secured Debt | Notes Payable
Debt Instrument [Line Items]
2016 (Remaining Six Months)	414,000
2,017	3,839,000
2,018	4,442,000
2,019	3,261,000
Total future minimum payments	11,956,000
Less amount representing interest	1,956,000
Notes payable, gross	10,000,000		$ 10,000,000
Unamortized discount on notes payable	(397,000)
Notes payable, balance	9,603,000
Less current portion of notes payable	1,021,000
Non-current portion of notes payable	$ 8,582,000

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	May 15, 2015
Class of Stock [Line Items]
Net loss	$ (7,103,000)	$ (6,221,000)	$ (14,617,000)	$ (12,872,000)
Stock issued during period, shares, new issues (in shares)			1,132,390	135,562
Common stock, par value, average (usd per share)	$ 2.77	$ 3.79	$ 2.77	$ 3.79
Proceeds from issuance of common stock, net of issuance costs			$ 3,130,000	$ 500,000
Proceeds from sale of common stock, net of underwriting discounts and issuance cost			2,982,000	$ 413,000
At the Market Issuance Sales Agreement [Member] | Cowen [Member]
Class of Stock [Line Items]
Common stock remained available to be sold under the sales agreement	$ 18,100,000		$ 18,100,000		$ 25,000,000

Stock-Based Compensation (Stock

Stock-Based Compensation (Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Shares available for grant (in shares)	1,299,301
Additional shares authorized (in shares)	1,400,000
Stock options granted (in shares)	(1,537,000)
Stock options canceled (in shares)	220,978
Shares available for grant (in shares)	1,383,279	1,299,301
Stock Options Outstanding
Beginning balance, options (in shares)	2,429,511
Stock options granted (in shares)	1,537,000
Stock options canceled (in shares)	(220,978)
Stock options exercised (in shares)	(11,969)
Ending balance, options (in shares)	3,733,564	2,429,511
Stock options vested and expected to vest (in shares)	3,595,695
Stock options exercisable (in shares)	1,381,095
Weighted-average Exercise Price Per Share
Weighted-average exercise price, options outstanding (in usd per share)	$ 7
Grants in period (in usd per share)	2.94
Canceled in period (in usd per share)	6.98
Exercises in period (in usd per share)	0.92
Weighted-average exercise price, options outstanding (in usd per share)	5.35	$ 7
Weighted-average exercise price, options exercisable (in usd per share)	5.41
Weighted-average exercise price, options vested and expected to vest (in usd per share)	$ 7.50
Weighted-average remaining contractual life, options outstanding (in years)	8 years 3 months 4 days	8 years 4 days
Weighted-average remaining contractual life, options vested and expected to vest (in years)	8 years 2 months 19 days
Weighted-average remaining contractual life, options exercisable (in years)	7 years 6 months
Aggregate Intrinsic value, options outstanding	$ 105	$ 287
Aggregate Intrinsic value, options vested and expected to vest	105
Aggregate Intrinsic value, options exercisable	$ 105

Stock-Based Compensation (Sto28

Stock-Based Compensation (Stock-based compensation expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,059	$ 937	$ 2,165	$ 1,902
Research and Development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	171	56	377	265
General and Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 888	$ 881	$ 1,788	$ 1,637

Stock-Based Compensation (Valua

Stock-Based Compensation (Valuation Assumptions) (Details) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Common stock options
Fair Value Assumptions and Methodology [Abstract]
Expected dividend yield (in percentage)	0.00%	0.00%	0.00%	0.00%
Risk free interest rate (in percentage)	1.25%	1.65%	1.25%	1.52%
Risk free interest rate, maximum (in percentage)	1.47%	2.08%	1.97%	2.08%
Expected volatility, minimum (in percentage)	74.00%	78.00%	74.00%	78.00%
Expected volatility, maximum (in percentage)	94.00%	92.00%	94.00%	92.00%
Common stock options | Minimum
Fair Value Assumptions and Methodology [Abstract]
Expected life in years (in years)	4 years 4 months 28 days	5 years 5 months 27 days	4 years 4 months 28 days	5 years 5 months 27 days
Common stock options | Maximum
Fair Value Assumptions and Methodology [Abstract]
Expected life in years (in years)	8 years 1 month 21 days	8 years 22 days	8 years 1 month 21 days	8 years 22 days
Vest On Market Condition [Member] | Non Qualified Stock Option [Member]
Fair Value Assumptions and Methodology [Abstract]
Expected dividend yield (in percentage)			0.00%
Risk free interest rate (in percentage)			1.82%
Risk free interest rate, maximum (in percentage)			2.05%
Expected volatility, minimum (in percentage)			77.00%
Expected volatility, maximum (in percentage)			89.00%
Vest On Market Condition [Member] | Non Qualified Stock Option [Member] | Minimum
Fair Value Assumptions and Methodology [Abstract]
Expected life in years (in years)			6 years 7 days
Weighted average fair vale per share (in usd per share)			$ 1.33
Vest On Market Condition [Member] | Non Qualified Stock Option [Member] | Maximum
Fair Value Assumptions and Methodology [Abstract]
Expected life in years (in years)			8 years
Weighted average fair vale per share (in usd per share)			$ 1.42

Stock-Based Compensation (Addit

Stock-Based Compensation (Additional Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	Jan. 06, 2016	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Apr. 30, 2016	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised				$ 25
Stock-based compensation expense		$ 1,059	$ 937	$ 2,165	$ 1,902
Number of shares authorized (in shares)							3,602,328
Stock options granted (in shares)				1,537,000
Common stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs not yet recognized		7,600		$ 7,600
Period for recognizing costs (in years)				2 years 3 months 18 days
Consultant Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 9		$ 19
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested options granted (in shares)		136,000		136,000
Vest On Market Condition [Member] | Non Qualified Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 29		$ 91
Stock options granted (in shares)	206,625
Minimum stock price for the options to vest (in usd per share)	$ 6
Minimum stock price for the options to vest, number of consecutive trading days (in days)	20 days
Expiration period (in years)	10 years
2011 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)						5,002,328

Net Loss Per Share (Schedule of

Net Loss Per Share (Schedule of Basic and Diluted Loss Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Numerator
Net loss	$ (7,103)	$ (6,221)	$ (14,617)	$ (12,872)
Denominator
Weighted average common shares outstanding used to compute net loss per share, basic and diluted (in shares)	21,552,089	19,772,345	21,248,027	19,759,923
Net loss per share of common stock, basic and diluted
Net loss per share (in usd per share)	$ (0.33)	$ (0.31)	$ (0.69)	$ (0.65)

Net Loss Per Share (Schedule 32

Net Loss Per Share (Schedule of Antidilutive Securities Excluded From Earnings Per Share) (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	4,707,650	2,952,814	4,682,214	2,962,148
Common stock warrants | Common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	1,026,249	931,942	1,026,249	932,237
Common stock options | Common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	3,681,401	2,020,872	3,655,965	2,029,911