REVA Medical (RVALL) 10-Q 9 Aug 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Aug. 01, 2017
Document And Entity Information [Abstract]
Entity Registrant Name	REVA Medical, Inc.
Entity Central Index Key	1,496,268
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Trading Symbol	RVA
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		41,167,017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 29,147,000	$ 6,674,000
Inventory	506,000
Prepaid expenses and other current assets	505,000	472,000
Total current assets	30,158,000	7,146,000
Non-Current Assets:
Property and equipment, net	1,900,000	2,277,000
Other non-current assets	13,000	60,000
Total non-current assets	1,913,000	2,337,000
Total Assets	32,071,000	9,483,000
Current Liabilities:
Accounts payable	949,000	778,000
Accrued expenses and other current liabilities	1,430,000	2,173,000
Convertible notes payable		91,655,000
Accrued interest on convertible notes payable		4,204,000
Total current liabilities	2,379,000	98,810,000
Long-Term Liabilities:
Convertible notes payable	116,778,000
Accrued interest on convertible notes payable	5,759,000
Common stock warrant liability	6,181,000
Other long-term liabilities	250,000	266,000
Total long-term liabilities	128,968,000	266,000
Total Liabilities	131,347,000	99,076,000
Commitments and contingencies (Note 7)
Stockholders' Deficit
Common stock	4,000	4,000
Undesignated preferred stock ― $0.0001 par value; 5,000,000 shares authorized; no shares issued or outstanding
Additional paid-in capital	289,090,000	299,641,000
Accumulated deficit	(388,370,000)	(389,238,000)
Total Stockholders' Deficit	(99,276,000)	(89,593,000)
Total Liabilities and Stockholders' Deficit	32,071,000	9,483,000
Class B common stock
Stockholders' Deficit
Common stock

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	41,167,017	42,851,477
Common stock, shares outstanding	41,167,017	42,851,477
Undesignated preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Undesignated preferred stock, shares authorized	5,000,000	5,000,000
Undesignated preferred stock, shares issued	0	0
Undesignated preferred stock, shares outstanding	0	0
Class B common stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	0	0
Common stock, shares outstanding	0	0

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Operating Expense:
Research and development	$ 3,083	$ 4,665	$ 7,047	$ 9,953
Selling, general, and administrative	1,977	2,366	4,079	4,559
Loss from operations	(5,060)	(7,031)	(11,126)	(14,512)
Other Income (Expense):
Interest expense	(3,079)	(505)	(3,670)	(1,010)
Loss on issuance of convertible notes payable and warrants to purchase common stock	(520)		(520)
Gain (loss) on change in fair value of convertible notes payable and warrant liability	8,178	2,966	16,316	(29,798)
Other income (expense)	(22)	15	(79)	(33)
Other income (expense)	4,557	2,476	12,047	(30,841)
Net Income (Loss) and Comprehensive Income (Loss)	$ (503)	$ (4,555)	$ 921	$ (45,353)
Net Income (Loss) Per Common Share:
Basic	$ (0.01)	$ (0.11)	$ 0.02	$ (1.09)
Diluted	$ (0.01)	$ (0.11)	$ (0.25)	$ (1.09)
Shares Used to Compute Net Income (Loss) per Share:
Basic	41,988,220	42,569,166	42,410,841	41,520,092
Diluted	41,988,220	42,569,166	53,916,997	41,520,092

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash Flows from Operating Activities:
Net income (loss)	$ 921,000	$ (45,353,000)
Non-cash adjustments to reconcile net income (loss) to net cash used for operating activities:
Depreciation and amortization	545,000	564,000
Loss on property and equipment disposal	43,000
Stock-based compensation	1,889,000	3,070,000
Interest expense on convertible notes payable	3,670,000	1,010,000
Loss on issuance of convertible notes payable and warrants to purchase common stock	520,000
Loss (gain) on change in fair value of convertible notes payable and warrant liability	(16,316,000)	29,798,000
Changes in operating assets and liabilities:
Inventory	(506,000)
Prepaid expenses and other current assets	(33,000)	110,000
Other non-current assets	47,000
Accounts payable	122,000	(277,000)
Accrued expenses and other current liabilities	(816,000)	(238,000)
Other long-term liabilities	(16,000)	(88,000)
Net cash used for operating activities	(9,930,000)	(11,404,000)
Cash Flows from Investing Activities:
Purchases of property and equipment	(164,000)	(370,000)
Net cash used for investing activities	(164,000)	(370,000)
Cash Flows from Financing Activities:
Proceeds from issuances of common stock		11,428,000
Repurchase of common stock	(12,493,000)
Proceeds from issuances of convertible notes payable and warrants, net	45,060,000
Net cash provided by financing activities	32,567,000	11,428,000
Net increase (decrease) in cash and cash equivalents	22,473,000	(346,000)
Cash and cash equivalents at beginning of period	6,674,000	16,895,000
Cash and Cash Equivalents at End of Period	29,147,000	16,549,000
Supplemental Non-Cash Information:
Property and equipment in accounts payable at end of period	65,000	100,000
Adjustment to beginning accumulated deficit upon adoption of ASU 2016-09	$ 53,000
Warrant liability transferred to equity upon exercise		$ 28,579,000

Background and Basis of Present

Background and Basis of Presentation	6 Months Ended
	Jun. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Background and Basis of Presentation	1. Background : REVA Medical, Inc. (“REVA” or the “Company”) was incorporated in California in 1998 under the name MD3, Inc. In March 2002, we changed our name to REVA Medical, Inc. In October 2010, we reincorporated in Delaware. We established a non-operating wholly owned subsidiary, REVA Germany GmbH, in 2007. In these notes the terms “us,” “we,” or “our” refer to REVA and our consolidated subsidiary unless context dictates otherwise. We are a medical device company that is focused on developing and commercializing products for use in humans, utilizing our proprietary polymer technologies. On April 3, 2017, our first product was approved for sale under a CE Mark, which allows us to market and sell in Europe and other jurisdictions that recognize the CE Mark. The product is our Fantom Fantom In December 2010 we completed an initial public offering of our common stock in Australia and registered with the U.S. Securities and Exchange Commission (“SEC”) and, consequently, became an SEC filer. Our stock is traded in the form of CHESS Depositary Interests (“CDIs”) on the Australian Securities Exchange (“ASX”); each share of our common stock is equivalent to ten CDIs. Our trading symbol is “RVA.AX.” We may pursue a listing of our common stock on a U.S. stock exchange, within the next year, at which time we would become dual-listed. Basis of Presentation : We have prepared the accompanying consolidated financial statements in accordance with U.S. generally accepted accounting principles (“GAAP”) and the rules and regulations of the SEC for reporting of interim financial information and, therefore, certain information and footnote disclosures normally included in annual financial statements have been omitted. Accordingly, these interim financial statements should be read in conjunction with Management’s Discussion and Analysis of Financial Condition and Results of Operations contained in this report and with the audited financial statements and accompanying footnotes included in our Annual Report on Form 10-K (“Form 10-K”) for the year ended December 31, 2016. Our consolidated financial statements include the accounts of REVA and our wholly owned subsidiary. All intercompany transactions and balances, if any, have been eliminated in consolidation. These interim consolidated financial statements are unaudited; the consolidated balance sheet as of December 31, 2016 was derived from the Company’s audited financial statements included in our Form 10-K for the year ended December 31, 2016. These interim financial statements have been prepared on the same basis as our annual financial statements and, in our opinion, all adjustments, consisting only of normal recurring accruals, considered necessary for a fair statement of the results of these interim periods have been included. The results of operations for the three- and six-month periods ended June 30, 2017 are not necessarily indicative of the results to be expected for the year ending December 31, 2017 or for any other interim period. Capital Resources : We had cash and cash equivalents totaling $29,147,000 as of June 30, 2017, which we believe will be sufficient to fund our operating and capital needs through at least the third quarter of 2018. These cash resources include approximately $32,567,000 in cash proceeds received during the second quarter of 2017 upon the issuance of convertible notes and warrants, net of costs of the transaction and the repurchase of common stock from one investor to the transaction. Although we have received CE Marking of our Fantom 1. (continued) Use of Estimates : In order to prepare our financial statements in conformity with GAAP, we make estimates and assumptions that affect the reported amounts in the financial statements and accompanying notes. Our most significant estimates relate to the fair value of our convertible notes payable, the fair value of our warrant liability, our operating expense accruals, and our stock-based compensation. Actual results could differ from our estimates. Inventory : We received CE Mark regulatory approval of our Fantom scaffold on April 3, 2017, at which time we began capitalizing raw material purchases and commercial scaffold production costs to inventory. Through June 30, 2017, we had not sold any product and our inventory consisted of $178,000 in raw materials, $16,000 of work-in-process, and $312,000 of finished goods, stated at the lower of cost or net realizable value based on the first-in, first-out cost method (“FIFO”). Our policy is to record an estimated allowance against inventory for unsalable, obsolete, or impaired inventory, with a corresponding increase to costs of revenue; through June 30, 2017, no inventory was considered to be unsalable, obsolete, or impaired and, therefore, no allowance was recorded. We record the cost of product used in research and development or clinical trials as research and development expense; we do not use commercial inventory for such purposes. Convertible Notes Payable : We analyze convertible notes payable at issue date to determine balance sheet classification, issue discounts or premiums, and embedded or derivative features. If embedded or derivative features give rise to separate accounting, we make an election to account for the notes at cost or at fair value. If fair value accounting is elected, on the issue date we record the difference between the issue price and the fair value of the combined securities issued in a transaction as a gain or loss in the consolidated statement of operations. We remeasure the fair value of the notes at each reporting date and record the change in fair value as a gain (upon a decrease in fair value) or a loss (upon an increase in fair value) as a component of other income (expense) in our consolidated statement of operations. Following our analysis of their embedded and derivative features, we elected fair value accounting for all issues of our convertible notes payable as management believes the notes will be converted into common stock, rather than repaid, and the fair value method presents an estimate of the value of the underlying common stock, and, therefore a more appropriate value of these liabilities than would be provided under the cost method. Common Stock Warrants : The fair value of warrants issued for the purchase of common stock is recorded as a liability whenever warrants call for issuance of registered shares upon exercise, a condition that we may not be able to accommodate and which would then result in a net settlement of the warrants. Until the time warrants are exercised or expire, we remeasure their fair value at each reporting date and record the change in fair value as a gain or loss component of other income (expense) in our consolidated statement of operations. Revenue : Through June 30, 2017, we had not recorded any revenue. Once we begin commercial sales, we will recognize revenue when title and risk of loss transfers to a customer, which is expected to be following shipment and when the customer’s right of return or replacement expires. Research and Development Costs : We expense our research and development costs as incurred. These costs include salaries, employee benefits, laboratory supplies, consulting services, production materials and services, preclinical and clinical costs, technology license fees, laboratory equipment depreciation, facility costs, certain indirect costs, and the costs to commercially manufacture our Fantom scaffold prior to receiving the CE Mark regulatory approval. Following regulatory approval on April 3, 2017, the costs of commercial manufacturing are capitalized to inventory. Recently Adopted Accounting Pronouncements : We adopted ASU 2016-09, Stock Compensation: Improvements to Employee Share-Based Payment Accounting , effective January 1, 2017. ASU 2016-09 simplifies certain aspects of accounting for stock-based compensation, including the accounting for income taxes, the option to recognize forfeiture credits as they occur rather than as an estimate of future activity, and classifications in the statement of cash flows. Upon the adoption, we recorded a cumulative effect adjustment to our accumulated deficit of approximately $53,000, with a corresponding increase to additional paid-in capital, to reverse our forfeiture estimate for unvested awards. All forfeitures occurring after adoption are being recognized in the consolidated statement of operations in the reporting period in which they occur. We had no forfeitures during the six months ended June 30, 2017. 1. (continued) Recent Accounting Pronouncements : In May 2014, ASU 2014-09, Revenue from Contracts with Customers (Topic 606) , was issued; several subsequent pronouncements were issued to clarify and refine the guidance in ASU 2014-09. The standard outlines a single comprehensive model to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance. Revenue recognized under ASU 2014-09 will represent the consideration an entity expects to be entitled to in exchange for the transfer of goods or services to a customer; it also requires additional disclosures about the nature, amount, timing, and uncertainty of revenue and cash flows arising from customer contracts. We will be required to adopt this pronouncement in the first quarter of 2018, using either a full retrospective or modified retrospective approach. Since we are currently launching commercial operations, had no commercial sales through June 30, 2017, and do not yet have a standard approach to customer contracting, we are evaluating ASU 2014-09 and plan to determine an implementation approach once we have established at least a small base of commercial customers and contracts. In February 2016, ASU 2016-02, Leases

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	2. We measure the fair value of our financial and non-financial assets and liabilities at each reporting date in accordance with the fair value hierarchy according to GAAP, which requires that f air value measurements be classified and disclosed in one of the following three categories: Level 1 – Quoted market prices for identical assets or liabilities in active markets at the measurement date; Level 2 – Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities in active or non-active markets, or other inputs that can be corroborated by observable market data for substantially the full term of an asset or liability; and, Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of an asset or liability, including management’s best estimate of the factors that market participants would use in pricing an asset or liability at the measurement date. We carry our convertible notes payable (the “Notes”) and common stock warrant liability at fair value; these recurring financial instruments are considered to be Level 3 financial liabilities. Through June 30, 2017, we carry our other assets and liabilities at amortized cost, which we consider to be reasonable estimates of their fair values due to their short-term nature and, therefore, do not provide their fair value information in the following table. Utilizing the lowest level inputs available under the measurement hierarchy, the fair values of our measured financial instruments, consisting only of liabilities, are as follows: Level 3 (in thousands) Fair Value of Liabilities at December 31, 2016: Convertible notes payable $ 91,655 Fair Value of Liabilities at June 30, 2017: Convertible notes payable $ 116,778 Common stock warrant liability 6,181 $ 122,959 We had no Level 1 or Level 2 financial instruments through June 30, 2017. 2. (continued) The fair values of our Notes were determined utilizing a Least Squares Monte Carlo simulation model; the fair value of our warrants to purchase common stock was determined using either a Least Squares Monte Carlo simulation model or a Black-Scholes valuation model, depending on their exercise price and other features. These models require use of unobservable inputs that are determined by management, with the assistance of independent experts. These inputs represent our best estimates, but involve certain inherent uncertainties. We use the market value of the underlying stock, a life equal to the contractual life of the financial instrument, incremental borrowing rates and bond yields that correspond to instruments of similar credit worthiness and the instrument’s remaining life, an estimate of volatility based on the historical prices of our trading securities, and we make assumptions as to our abilities to test and commercialize our product(s), to obtain future financings when and if needed, to comply with the terms and conditions of our Notes, and the probability of a change in control event. A summary of the assumptions used to value these Level 3 securities is as follows: December 31, June 30, 2016 2017 Market price per share of common stock $7.88 $6.60 Risk-free interest rate 2.0% 1.9% Expected volatility of common stock 80.0% 45.0% Expected life (in years) 2.87 2.37 – 4.96 Bond yield of equivalent securities 27.0% 25.4% – 27.1% A significant change in the market price per share, expected volatility, or bond yield of equivalent securities, in isolation, would result in significantly higher or lower fair value measurements. In combination, changes in these inputs could result in a significantly higher or lower fair value measurement if the input changes were to be aligned, or could result in a minimally higher or lower fair value measurement if the input changes were of a compensating nature. We recorded a total of $2,966,000 and $8,178,000 in unrealized gains during the three-month periods, and a total of $29,798,000 in unrealized losses and $16,316,000 in unrealized gains during the six-month periods, ended June 30, 2016 and 2017, respectively, that arose from the change in fair value on our Level 3 financial liabilities. Our Level 3 fair value activity through June 30, 2017 is as follows: Level 3 (in thousands) Balance at December 31, 2016 $ 91,655 Gain from Change in Fair Value: Convertible notes payable (8,138 ) Balance at March 31, 2017 83,517 Fair Value on Issuance Dates: Convertible notes payable 40,954 Warrants to purchase common stock 6,666 Gain from Change in Fair Value: Convertible notes payable (7,693 ) Warrants to purchase common stock (485 ) Balance at June 30, 2017 $ 122,959

Convertible Notes Payable and W

Convertible Notes Payable and Warrants to Purchase Common Stock	6 Months Ended
	Jun. 30, 2017
Convertible Notes Payable [Abstract]
Convertible Notes Payable and Warrants to Purchase Common Stock	3. Convertible Notes Payable and Warrants to Purchase Common Stock In May 2017, we issued 338 convertible notes and in June 2017 we issued 133 convertible notes (collectively, the “2017 Notes”), each with a face value of $100,000, for total gross cash proceeds of $47,100,000. From these cash proceeds, we repurchased 1,732,260 shares of our common stock from one of the 2017 Note investors at $7.212 per share, for a total repurchase of $12,493,000, and incurred transaction costs of $2,115,000, leaving us with net proceeds of $32,492,000. The 2017 Notes are convertible at any time at the holders’ election; the conversion rate as of June 30, 2017 was $8.655 per share, which would result in issuing 5,441,941 shares of common stock upon conversion. The conversion rate is downward adjustable based on the issue price of securities in a future Company financing, if any, to a minimum of $7.212 per share. The 2017 Notes mature five years from issue date, if not converted or redeemed earlier. Interest accrues at the rate of 8.0 percent per annum, compounded annually, and is payable upon redemption or maturity; accrued interest is not payable or convertible upon conversion of the notes. Holders of the 2017 Notes have a right to request redemption of the notes (face value plus accrued interest) on November 4, 2019, if they have not been previously converted or redeemed, if the holders have provided at least 30 days’ written notice to elect such a redemption. On their issue dates, we evaluated the 2017 Notes and, following an analysis of the embedded and derivative features, made an irrevocable election to account for the notes at fair value. The fair value on June 30, 2017 was estimated to be $6,259,000 below the $47,100,000 face value of the 2017 Notes. A decrease of $113,000 in the fair value of the notes between their issue dates in May and June 2017 and the June 30, 2017 reporting date was recorded as a gain in our consolidated statement of operations. In addition to the $2,115,000 transaction costs, which we recorded as interest expense in our consolidated statement of operations upon the fair value accounting election, we accrued a total of $474,000 in interest expense on the 2017 Notes for the period from issue date to June 30, 2017. In November 2014, we issued 250 convertible notes (the “2014 Notes”), each with a face value of $100,000, for total gross cash proceeds of $25,000,000. The 2014 Notes are convertible at any time at the holders’ election into a total of 11,506,155 shares of common stock, which is a conversion rate of $2.17275 per share. The 2014 Notes mature on November 14, 2019, if not converted or redeemed earlier. Interest accrues at the rate of 7.54 percent per annum, compounded annually, and is payable upon redemption or maturity; accrued interest is not payable or convertible upon conversion of the 2014 Notes. Effective June 1, 2017, upon stockholder approval, the one-time option for holders to redeem the notes on June 30, 2017 and the provision for an automatic conversion of the notes were eliminated and the 2014 Notes were modified to be subordinated to the 2017 Notes. On their issue date, we evaluated the 2014 Notes and, following an analysis of the embedded and derivative features, we made an irrevocable election to account for the notes at fair value. Following the June 1, 2017 modifications, we continued to account for the 2014 Notes under the fair value method. The fair values of the 2014 Notes as of December 31, 2016 and June 30, 2017 were calculated to be $66,655,000 and $50,937,000, respectively, higher than the unpaid principal balance of the Notes of $25,000,000. The increase of $29,798,000 and the decrease of $15,718,000 in the fair value of the Notes during the six months ended June 30, 2016 and 2017, respectively, were recorded as a loss and a gain, respectively, in our consolidated statement of operations. We accrued $505,000 and $544,000 for the three-month periods, and $1,011,000 and $1,081,000 for the six-month periods, ended June 30, 2016 and 2017, respectively, in interest expense on the 2014 Notes. In connection with issuing the 2017 Notes, in May 2017 and June 2017 we issued warrants to purchase up to 2,119,500 shares of common stock. The warrants are immediately exercisable and expire five years from issue date. Through June 30, 2017, the exercisable price of the warrants was $5.00 per share; the exercise price could be adjusted upward to a maximum of $7.212 per share, based on the issue price of securities in a future Company financing, if any. The fair value of the warrants on June 30, 2017 was estimated to be $485,000 less than the fair value on issue date, which we recorded as a gain on change in fair value in our consolidated statement of operations. The aggregate fair value of the 2017 Notes and warrants on their issue dates was estimated to be $47,620,000, which was $520,000 higher than the $47,100,000 issue price; we recorded this difference as a loss on issuance in the consolidated statement of operations. The warrants we issued in November 2014 in connection with issuing the 2014 Notes were exercised in full on or before February 12, 2016. Prior to their exercise, we recorded their change in fair value in our consolidated statement of operations. The loss on change in fair value from January 1, 2016 to February 12, 2016 was $8,957,000.

Balance Sheet Details

Balance Sheet Details	6 Months Ended
	Jun. 30, 2017
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Details	4. Property and Equipment and Accrued Expenses : Components of our property and equipment and accrued expenses and other current liabilities are as follows: December 31, June 30, 2016 2017 (in thousands) Property and Equipment: Furniture, office equipment, and software $ 655 $ 655 Laboratory equipment 6,604 6,112 Leasehold improvements 2,412 2,412 9,671 9,179 Accumulated depreciation and amortization (7,394 ) (7,279 ) $ 2,277 $ 1,900 Accrued Expenses and Other Current Liabilities: Accrued salaries and other employee costs $ 1,456 $ 836 Accrued operating expenses 519 481 Accrued use taxes and other 198 113 $ 2,173 $ 1,430

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	5. We have reported tax net operating losses since our inception through June 30, 2017; therefore, no provision for income taxes has been recorded since our inception. The net operating tax loss carryforwards arising from our net losses may be available to offset future taxable income for income tax purposes; however, under Internal Revenue Code (“IRC”) Sections 382 and 383, use of the net operating tax loss carryforwards, as well as our research tax credit carryforwards, may be limited based on cumulative changes in ownership. We have established a valuation allowance against our net deferred tax assets due to the uncertainty surrounding the realization of those assets and we, therefore, have no deferred asset or liability balance for any reporting period. We periodically evaluate the recoverability of the deferred tax assets and, when it is determined that it is more-likely-than-not that the deferred tax assets are realizable, the valuation allowance will be reduced. Due to our valuation allowance, future changes in our unrecognized tax benefits will not impact our effective tax rate.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	6. The Plan : Our 2010 Equity Incentive Plan, as amended (the “Plan”), provides for grants of incentive and non-qualified stock options for purchase of our common stock at a price per share equal to the closing market price on the date of grant and for awards of restricted stock units (“RSUs”) and restricted stock, for which there is no consideration payable by the recipient. The number of shares reserved for issuance under the Plan may be increased annually by up to three percent of the outstanding stock of the Company and on January 1, 2017, an additional 1,285,544 shares were reserved for issuance under the Plan. An aggregate of 9,266,190 shares are reserved for issuance under the Plan as of June 30, 2017. One share of common stock is issued for each stock option that is exercised or each RSU that vests. All stock issuances under the Plan are made with new shares from our authorized but unissued common stock. The term of grants and awards under the Plan may not exceed ten years. 6. (continued) Employees, non-employee directors, and consultants are eligible to participate in the Plan. For purposes of determining stock-based compensation expense, we include non-employee directors with employees; we account for consultant compensation expense separately. Option activity under the Plan is as follows: Weighted Average Options Exercise Outstanding Price Balance at December 31, 2015 5,912,425 $6.46 Granted 570,100 $8.22 Cancelled (106,834 ) $10.81 Exercised (247,499 ) $4.04 Balance at December 31, 2016 6,128,192 $6.65 Granted 474,600 $7.60 Cancelled (6,980 ) $5.95 Balance at June 30, 2017 6,595,812 $6.72 Vesting periods of stock and unit awards and option grants are determined by the Company’s board of directors. The majority of options granted by the Company vest over four years, with 25 percent vesting on the one-year anniversary of the vesting commencement date and 75 percent vesting in equal monthly installments thereafter. A majority of those options are exercisable at any time but, if exercised, are subject to a lapsing right of repurchase by us at the exercise price until fully vested. During March 2015, we granted a total of 316,000 options that vest based on certain performance milestones of the Company. We estimated the vesting term for each performance objective on the date of grant, and on each reporting date thereafter, based on our internal timelines and operating projections. Our estimates of vesting ranged from approximately nine to 30 months at the grant date in March 2015; we estimated the remaining vesting term to be 12 months as of December 31, 2016 and to be nine months as of June 30, 2017. A total of 65 percent of these options had vested as of June 30, 2017; a total of 12,250 were cancelled during the year ended December 31, 2016 and none were cancelled during the six months ended June 30, 2017. During January 2013 and May 2013 we awarded 40,000 shares, and 47,500 shares, respectively, of restricted stock; 25 percent of each award vests on each annual anniversary date of the award. As of June 30, 2017 all of these awards had vested and none had been cancelled. During March 2015, we awarded 824,200 RSUs to employees. These RSUs vest based on certain performance milestones of the Company. We estimated the vesting term for each performance objective on the award date, and on each reporting date thereafter, based on our internal timelines and operating projections. Our estimates of vesting ranged from approximately 21 to 30 months at the award date in March 2015; we estimated the remaining weighted average vesting term to be 8.1 months as of December 31, 2016 and to be 10.1 months as of June 30, 2017. None of these RSUs had vested as of June 30, 2017; a total of 118,000 were cancelled during the year ended December 31, 2016 and none were cancelled during the six months ended June 30, 2017. During May 2016, we awarded 35,200 RSUs and during July 2016 we awarded 12,600 RSUs to non-employee directors; all of these RSUs vested on May 25, 2017 and none were cancelled. During March 2017, we awarded 175,550 RSUs and during May 2017 we awarded 29,250 RSUs to employees; one-third of each award vests on each annual anniversary date of the award. Through June 30, 2017, none of these RSUs had been cancelled. No tax benefits arising from stock-based compensation have been recognized in the consolidated statements of operations and comprehensive loss through June 30, 2017. 6. (continued) Grants and Awards to Employees : We account for option grants, restricted stock awards, and RSU awards to employees based on their estimated fair values on the date of grant or award, with the resulting stock-based compensation recorded over the requisite service period on a straight-line basis. For the options and RSUs that vest upon performance milestones, we estimate the probability that the performance milestones will be met and record the related stock-based compensation expense. During the three months ended March 31, 2016, we determined that two of the three performance targets for our performance-based awards continued to be probable of being achieved and, therefore, we recorded straight-line quarterly expense of $344,000 for those awards only. During the three months ended June 30, 2016, we determined that all three of the performance targets were probable of being achieved, and, therefore, recorded cumulative expense for the third performance target during the second quarter of 2016. We continued to believe all three performance targets were probable of being achieved through June 30, 2017 and recorded straight-line expense of $128,000 and $208,000 for the awards during the respective three- and six-month periods ended June 30, 2017. Stock-based compensation arising from employee options and awards under the Plan is as follows: Three Months Ended Six Months Ended June 30, June 30, 2016 2017 2016 2017 (in thousands) (in thousands) Employee Stock-Based Compensation: Research and development expense $ 800 $ 184 $ 1,164 $ 346 Selling, general, and administrative expense 1,075 793 1,866 1,543 $ 1,875 $ 977 $ 3,030 $ 1,889 The fair value of restricted stock and RSU awards is equal to the closing market price of our common stock on the date of award. The fair value of options granted was estimated on the date of grant using the following weighted-average assumptions: Six Months Ended June 30, 2016 2017 Risk-free interest rate 1.6% 2.3% Expected volatility of common stock 57.5% 66.1% Expected life in years 6.17 6.25 Dividend yield 0% 0% The assumed risk-free interest rate was based on the implied yield on a U.S. Treasury zero-coupon issue with a remaining term equal to the expected life of the option. The assumed volatility through June 30, 2016 was calculated based on the historical market prices of a selected group of publicly traded companies considered to be our peers; we used peer group data due to our limited historical trading data but adjusted the 2016 volatility upward by approximately ten percent to allow us to move toward using our trading history, which is more volatile than our peer group. Beginning in 2017, we use our historical market prices; our securities began trading on our IPO date of December 23, 2010, which provides approximately 6.5 years’ history as of June 30, 2017. For options that vest based on passage of time, the expected option life was calculated using the simplified method under the accounting standard for stock compensation and a ten-year option expiration; we use the simplified method because we do not yet have adequate option activity history to establish a reasonable expected life. For options that vest based on performance achievements, the expected life was calculated based on the requisite service periods estimated by management and a ten-year option expiration. The expected dividend yield of zero reflects that we have not paid cash dividends since inception and do not intend to pay cash dividends in the foreseeable future. The options granted to employees during the six months ended June 30, 2017 had a weighted average grant date fair value of $4.70. The aggregate intrinsic value of options exercised during the six months ended June 30, 2016 was $92,000; no options were exercised during the six months ended June 30, 2017.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2017
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. Commitments and Contingencies We have licensed certain patents and other intellectual property rights related to the composition and coating of our scaffolds and other biomaterial technologies. Terms of these licenses include provisions for royalty payments upon sales of products utilizing the technology. The amount of royalty varies depending upon type of product, use of product, stage of product, location of sale, and ultimate sales volume, and ranges from a minimum of approximately $15 per unit to a maximum of approximately $50 per unit sold, with license provisions for escalating minimum royalties that could be as high as $2,200,000 per year. Additionally, in the event we sublicense the technology and receive certain milestone payments, the licenses require that up to 40 percent of the milestone amount be paid to the licensors. Additional terms of the technology licenses include annual licensing payments of $175,000 until the underlying technology has been commercialized. Since commercial sales of our Fantom

Net Income (Loss) Per Common Sh

Net Income (Loss) Per Common Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Net Income (Loss) Per Common Share	8. Basic net income (loss) per common share is calculated by dividing the net income (loss) attributable to common stockholders by the weighted average number of common shares outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted average number of common share equivalents outstanding for the period determined using the treasury-stock method and the if-converted method, as applicable. For this calculation, common stock options and restricted stock subject to forfeiture are considered to be common stock equivalents; common stock equivalents are used in the calculation of diluted net loss per share only when their effect is dilutive. Basic net income (loss) per share reconciles to fully diluted net loss per share as follows (dollars in thousands): Three Months Ended Six Months Ended June 30, June 30, 2016 2017 2016 2017 Diluted Net Loss: Net income (loss) used for basic net income (loss) per share $ (4,555 ) $ (503 ) $ (45,353 ) $ 921 Interest expense on convertible notes payable — — — 1,081 Gain on change in fair value of convertible notes payable — — — (15,718 ) $ (4,555 ) $ (503 ) $ (45,353 ) $ (13,716 ) Weighted Average Shares Used to Compute Diluted Net Loss per Share: Shares used for basic net income (loss) per share 42,569,166 41,988,220 41,520,092 42,410,841 Common share equivalents — — — 11,506,156 42,569,166 41,988,220 41,520,092 53,916,997 8. (continued) The following weighted average shares were excluded from the computations of diluted net loss per share because including them would have been antidilutive. Three Months Ended Six Months Ended June 30, June 30, 2016 2017 2016 2017 Weighted Average Shares Excluded from EPS: Options to purchase common stock 6,414,854 6,565,952 6,300,137 6,375,868 Unvested restricted stock 37,693 7,569 40,562 10,428 Restricted stock units 931,699 923,411 957,949 850,813 Warrants to purchase common stock — 1,068,083 1,009,615 536,991 Common share equivalents of convertible notes 11,506,156 14,248,521 11,506,156 12,884,914 18,890,402 22,813,536 19,814,419 20,659,014

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	9. On July 13, 2017, we announced that two executives would retire and that ten additional employees had been terminated as the Company transitions from research and development activities to commercial operations. As a result, during the third quarter of 2017, the Company anticipates incurring $570,000 in severance expense, of which approximately $300,000 is expected to be paid by September 30, 2017 and the remainder is expected to be paid between October 1, 2017 and March 31, 2018. Additionally, upon retirement or termination date, all unvested equity grants or awards will be forfeited by these employees. The Company expects to reverse approximately $1,817,000 in stock compensation expense during the three months ended September 30, 2017 related to these unvested forfeits.

Background and Basis of Prese15

Background and Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation : We have prepared the accompanying consolidated financial statements in accordance with U.S. generally accepted accounting principles (“GAAP”) and the rules and regulations of the SEC for reporting of interim financial information and, therefore, certain information and footnote disclosures normally included in annual financial statements have been omitted. Accordingly, these interim financial statements should be read in conjunction with Management’s Discussion and Analysis of Financial Condition and Results of Operations contained in this report and with the audited financial statements and accompanying footnotes included in our Annual Report on Form 10-K (“Form 10-K”) for the year ended December 31, 2016. Our consolidated financial statements include the accounts of REVA and our wholly owned subsidiary. All intercompany transactions and balances, if any, have been eliminated in consolidation. These interim consolidated financial statements are unaudited; the consolidated balance sheet as of December 31, 2016 was derived from the Company’s audited financial statements included in our Form 10-K for the year ended December 31, 2016. These interim financial statements have been prepared on the same basis as our annual financial statements and, in our opinion, all adjustments, consisting only of normal recurring accruals, considered necessary for a fair statement of the results of these interim periods have been included. The results of operations for the three- and six-month periods ended June 30, 2017 are not necessarily indicative of the results to be expected for the year ending December 31, 2017 or for any other interim period.
Capital Resources	Capital Resources : We had cash and cash equivalents totaling $29,147,000 as of June 30, 2017, which we believe will be sufficient to fund our operating and capital needs through at least the third quarter of 2018. These cash resources include approximately $32,567,000 in cash proceeds received during the second quarter of 2017 upon the issuance of convertible notes and warrants, net of costs of the transaction and the repurchase of common stock from one investor to the transaction. Although we have received CE Marking of our Fantom
Use of Estimates	Use of Estimates : In order to prepare our financial statements in conformity with GAAP, we make estimates and assumptions that affect the reported amounts in the financial statements and accompanying notes. Our most significant estimates relate to the fair value of our convertible notes payable, the fair value of our warrant liability, our operating expense accruals, and our stock-based compensation. Actual results could differ from our estimates.
Inventory	Inventory : We received CE Mark regulatory approval of our Fantom scaffold on April 3, 2017, at which time we began capitalizing raw material purchases and commercial scaffold production costs to inventory. Through June 30, 2017, we had not sold any product and our inventory consisted of $178,000 in raw materials, $16,000 of work-in-process, and $312,000 of finished goods, stated at the lower of cost or net realizable value based on the first-in, first-out cost method (“FIFO”). Our policy is to record an estimated allowance against inventory for unsalable, obsolete, or impaired inventory, with a corresponding increase to costs of revenue; through June 30, 2017, no inventory was considered to be unsalable, obsolete, or impaired and, therefore, no allowance was recorded. We record the cost of product used in research and development or clinical trials as research and development expense; we do not use commercial inventory for such purposes.
Convertible Notes Payable	Convertible Notes Payable : We analyze convertible notes payable at issue date to determine balance sheet classification, issue discounts or premiums, and embedded or derivative features. If embedded or derivative features give rise to separate accounting, we make an election to account for the notes at cost or at fair value. If fair value accounting is elected, on the issue date we record the difference between the issue price and the fair value of the combined securities issued in a transaction as a gain or loss in the consolidated statement of operations. We remeasure the fair value of the notes at each reporting date and record the change in fair value as a gain (upon a decrease in fair value) or a loss (upon an increase in fair value) as a component of other income (expense) in our consolidated statement of operations. Following our analysis of their embedded and derivative features, we elected fair value accounting for all issues of our convertible notes payable as management believes the notes will be converted into common stock, rather than repaid, and the fair value method presents an estimate of the value of the underlying common stock, and, therefore a more appropriate value of these liabilities than would be provided under the cost method.
Common Stock Warrants	Common Stock Warrants : The fair value of warrants issued for the purchase of common stock is recorded as a liability whenever warrants call for issuance of registered shares upon exercise, a condition that we may not be able to accommodate and which would then result in a net settlement of the warrants. Until the time warrants are exercised or expire, we remeasure their fair value at each reporting date and record the change in fair value as a gain or loss component of other income (expense) in our consolidated statement of operations.
Revenue	Revenue : Through June 30, 2017, we had not recorded any revenue. Once we begin commercial sales, we will recognize revenue when title and risk of loss transfers to a customer, which is expected to be following shipment and when the customer’s right of return or replacement expires.
Research and Development Costs	Research and Development Costs : We expense our research and development costs as incurred. These costs include salaries, employee benefits, laboratory supplies, consulting services, production materials and services, preclinical and clinical costs, technology license fees, laboratory equipment depreciation, facility costs, certain indirect costs, and the costs to commercially manufacture our Fantom scaffold prior to receiving the CE Mark regulatory approval. Following regulatory approval on April 3, 2017, the costs of commercial manufacturing are capitalized to inventory.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements : We adopted ASU 2016-09, Stock Compensation: Improvements to Employee Share-Based Payment Accounting , effective January 1, 2017. ASU 2016-09 simplifies certain aspects of accounting for stock-based compensation, including the accounting for income taxes, the option to recognize forfeiture credits as they occur rather than as an estimate of future activity, and classifications in the statement of cash flows. Upon the adoption, we recorded a cumulative effect adjustment to our accumulated deficit of approximately $53,000, with a corresponding increase to additional paid-in capital, to reverse our forfeiture estimate for unvested awards. All forfeitures occurring after adoption are being recognized in the consolidated statement of operations in the reporting period in which they occur. We had no forfeitures during the six months ended June 30, 2017.
Recent Accounting Pronouncements	Recent Accounting Pronouncements : In May 2014, ASU 2014-09, Revenue from Contracts with Customers (Topic 606) , was issued; several subsequent pronouncements were issued to clarify and refine the guidance in ASU 2014-09. The standard outlines a single comprehensive model to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance. Revenue recognized under ASU 2014-09 will represent the consideration an entity expects to be entitled to in exchange for the transfer of goods or services to a customer; it also requires additional disclosures about the nature, amount, timing, and uncertainty of revenue and cash flows arising from customer contracts. We will be required to adopt this pronouncement in the first quarter of 2018, using either a full retrospective or modified retrospective approach. Since we are currently launching commercial operations, had no commercial sales through June 30, 2017, and do not yet have a standard approach to customer contracting, we are evaluating ASU 2014-09 and plan to determine an implementation approach once we have established at least a small base of commercial customers and contracts. In February 2016, ASU 2016-02, Leases

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Schedule of fair values of investments and liabilities, determined from level 3 inputs	Level 3 (in thousands) Fair Value of Liabilities at December 31, 2016: Convertible notes payable $ 91,655 Fair Value of Liabilities at June 30, 2017: Convertible notes payable $ 116,778 Common stock warrant liability 6,181 $ 122,959
Summary of assumptions used to value Level 3 securities	A summary of the assumptions used to value these Level 3 securities is as follows: December 31, June 30, 2016 2017 Market price per share of common stock $7.88 $6.60 Risk-free interest rate 2.0% 1.9% Expected volatility of common stock 80.0% 45.0% Expected life (in years) 2.87 2.37 – 4.96 Bond yield of equivalent securities 27.0% 25.4% – 27.1%
Summary of fair value of financial liabilities determined from "Level 3" inputs	Level 3 (in thousands) Balance at December 31, 2016 $ 91,655 Gain from Change in Fair Value: Convertible notes payable (8,138 ) Balance at March 31, 2017 83,517 Fair Value on Issuance Dates: Convertible notes payable 40,954 Warrants to purchase common stock 6,666 Gain from Change in Fair Value: Convertible notes payable (7,693 ) Warrants to purchase common stock (485 ) Balance at June 30, 2017 $ 122,959

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	6 Months Ended
	Jun. 30, 2017
Balance Sheet Related Disclosures [Abstract]
Schedule of Property and Equipment	Property and Equipment and Accrued Expenses : Components of our property and equipment and accrued expenses and other current liabilities are as follows: December 31, June 30, 2016 2017 (in thousands) Property and Equipment: Furniture, office equipment, and software $ 655 $ 655 Laboratory equipment 6,604 6,112 Leasehold improvements 2,412 2,412 9,671 9,179 Accumulated depreciation and amortization (7,394 ) (7,279 ) $ 2,277 $ 1,900 Accrued Expenses and Other Current Liabilities: Accrued salaries and other employee costs $ 1,456 $ 836 Accrued operating expenses 519 481 Accrued use taxes and other 198 113 $ 2,173 $ 1,430
Schedule of Accrued Expenses and Other Current Liabilities	December 31, June 30, 2016 2017 (in thousands) Property and Equipment: Furniture, office equipment, and software $ 655 $ 655 Laboratory equipment 6,604 6,112 Leasehold improvements 2,412 2,412 9,671 9,179 Accumulated depreciation and amortization (7,394 ) (7,279 ) $ 2,277 $ 1,900 Accrued Expenses and Other Current Liabilities: Accrued salaries and other employee costs $ 1,456 $ 836 Accrued operating expenses 519 481 Accrued use taxes and other 198 113 $ 2,173 $ 1,430

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2017
Schedule of the option activity under the plan	Weighted Average Options Exercise Outstanding Price Balance at December 31, 2015 5,912,425 $6.46 Granted 570,100 $8.22 Cancelled (106,834 ) $10.81 Exercised (247,499 ) $4.04 Balance at December 31, 2016 6,128,192 $6.65 Granted 474,600 $7.60 Cancelled (6,980 ) $5.95 Balance at June 30, 2017 6,595,812 $6.72
Equity awards to employees
Schedule of stock-based compensation expense	Stock-based compensation arising from employee options and awards under the Plan is as follows: Three Months Ended Six Months Ended June 30, June 30, 2016 2017 2016 2017 (in thousands) (in thousands) Employee Stock-Based Compensation: Research and development expense $ 800 $ 184 $ 1,164 $ 346 Selling, general, and administrative expense 1,075 793 1,866 1,543 $ 1,875 $ 977 $ 3,030 $ 1,889
Options Granted
Schedule of the weighted-average assumptions used to estimate fair value of options granted	The fair value of options granted was estimated on the date of grant using the following weighted-average assumptions: Six Months Ended June 30, 2016 2017 Risk-free interest rate 1.6% 2.3% Expected volatility of common stock 57.5% 66.1% Expected life in years 6.17 6.25 Dividend yield 0% 0%

Net Income (Loss) Per Common 19

Net Income (Loss) Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Schedule of basic net income (loss) per share reconciles to fully diluted net loss per share	Basic net income (loss) per share reconciles to fully diluted net loss per share as follows (dollars in thousands): Three Months Ended Six Months Ended June 30, June 30, 2016 2017 2016 2017 Diluted Net Loss: Net income (loss) used for basic net income (loss) per share $ (4,555 ) $ (503 ) $ (45,353 ) $ 921 Interest expense on convertible notes payable — — — 1,081 Gain on change in fair value of convertible notes payable — — — (15,718 ) $ (4,555 ) $ (503 ) $ (45,353 ) $ (13,716 ) Weighted Average Shares Used to Compute Diluted Net Loss per Share: Shares used for basic net income (loss) per share 42,569,166 41,988,220 41,520,092 42,410,841 Common share equivalents — — — 11,506,156 42,569,166 41,988,220 41,520,092 53,916,997
Schedule of weighted average shares excluded from the computation of diluted net loss per share	8. (continued) The following weighted average shares were excluded from the computations of diluted net loss per share because including them would have been antidilutive. Three Months Ended Six Months Ended June 30, June 30, 2016 2017 2016 2017 Weighted Average Shares Excluded from EPS: Options to purchase common stock 6,414,854 6,565,952 6,300,137 6,375,868 Unvested restricted stock 37,693 7,569 40,562 10,428 Restricted stock units 931,699 923,411 957,949 850,813 Warrants to purchase common stock — 1,068,083 1,009,615 536,991 Common share equivalents of convertible notes 11,506,156 14,248,521 11,506,156 12,884,914 18,890,402 22,813,536 19,814,419 20,659,014

Background and Basis of Prese20

Background and Basis of Presentation (Details)	3 Months Ended	6 Months Ended
	Jun. 30, 2017USD ($)	Jun. 30, 2017USD ($)itemCountryPatient	Jan. 02, 2017USD ($)	Dec. 31, 2016USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2010
Organization Consolidation And Basis Of Presentation Of Financial Statements [Line Items]
Number of patients enrolled in a clinical trial of bioresorbable stent product | item		247
Number of countries | Country		8
Number of patients data used | Patient		117
Common Stock Conversion Rate							10
Cash and cash equivalents	$ 29,147,000	$ 29,147,000		$ 6,674,000	$ 16,549,000	$ 16,895,000
Cash proceeds received upon issuance of convertible notes and warrants, net of costs	32,567,000	45,060,000
Inventory of raw materials	178,000	178,000
Inventory of work-in-process	16,000	16,000
Inventory of finished goods	312,000	312,000
Unsalable, obsolete or impaired inventory	0	0
Inventory allowance	0	0
Revenue		0
Revenue from commercial sales		0
ASU 2016-09
Organization Consolidation And Basis Of Presentation Of Financial Statements [Line Items]
Effect of accumulated deficit			$ 53,000
Effect of accumulated deficit due to forfeiture	$ 0	$ 0

Fair Value Measurements (Detail

Fair Value Measurements (Details 1) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Common stock warrant liability	$ 6,181
Level 3
Convertible notes payable	116,778	$ 91,655
Common stock warrant liability	6,181
Liabilities	$ 122,959

Fair Value Measurements (Deta22

Fair Value Measurements (Details 2) - Level 3 - $ / shares	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Weighted Average Assumptions:
Market price per share of common stock	$ 6.60	$ 7.88
Risk-free interest rate	1.90%	2.00%
Expected volatility of common stock	45.00%	80.00%
Expected life (in years)		2 years 10 months 13 days
Bond yield of equivalent securities		27.00%
Minimum
Weighted Average Assumptions:
Expected life (in years)	2 years 4 months 13 days
Bond yield of equivalent securities	25.40%
Maximum
Weighted Average Assumptions:
Expected life (in years)	4 years 11 months 15 days
Bond yield of equivalent securities	27.10%

Fair Value Measurements (Deta23

Fair Value Measurements (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Changes in unrealized gain (loss) on instruments held at the end of period, financial liabilities	$ 8,178,000	$ 2,966,000	$ 16,316,000	$ (29,798,000)
Level 3
Changes in unrealized gain (loss) on instruments held at the end of period, financial liabilities	$ 8,178,000	$ 2,966,000	$ 16,316,000	$ (29,798,000)

Fair Value Measurements (Deta24

Fair Value Measurements (Details 3) - USD ($)	2 Months Ended	3 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Fair Value on Issuance Dates:
Warrants to purchase common stock	$ 6,181,000	$ 6,181,000
2017 Notes
Gain from Change in Fair Value:
Warrants to purchase common stock	485,000
Level 3
Financial Liabilities Fair Value Disclosure
Beginning balance		83,517,000	$ 91,655,000
Fair Value on Issuance Dates:
Convertible notes payable	116,778,000	116,778,000		$ 91,655,000
Warrants to purchase common stock	6,181,000	6,181,000
Gain from Change in Fair Value:
Convertible notes payable		(7,693,000)	(8,138,000)
Warrants to purchase common stock		(485,000)
Ending balance	122,959,000	122,959,000	$ 83,517,000
Level 3 | 2017 Notes
Fair Value on Issuance Dates:
Convertible notes payable	40,954,000	40,954,000
Warrants to purchase common stock	$ 6,666,000	$ 6,666,000

Convertible Notes Payable and25

Convertible Notes Payable and Warrants to Purchase Common Stock (Details)	1 Months Ended				2 Months Ended	3 Months Ended				6 Months Ended
	Jun. 30, 2017USD ($)item$ / shares	May 31, 2017USD ($)item	Feb. 12, 2016USD ($)	Nov. 30, 2014USD ($)sharesitem$ / shares	Jun. 30, 2017USD ($)$ / sharesshares	Jun. 30, 2017USD ($)$ / shares	Mar. 31, 2017USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Jun. 30, 2017USD ($)shares$ / shares	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Gain (loss) on change in fair value of convertible notes payable and warrant liability						$ 8,178,000		$ 2,966,000		$ 16,316,000	$ (29,798,000)
Interest on convertible notes payable										3,670,000	1,010,000
Loss on issuance of convertible notes payable and warrants						$ (520,000)				$ (520,000)
2017 Notes
Change in fair value of warrants					$ 485,000
2017 Notes | Warrants to purchase common stock
Warrants issued to purchase common stock | shares					2,119,500
Warrants useful life										5 years
Warrants exercise price | $ / shares	$ 5				$ 5	$ 5				$ 5
2017 Notes | Maximum | Warrants to purchase common stock
Warrants exercise price | $ / shares	$ 7.212				$ 7.212	$ 7.212				$ 7.212
2014 Notes
Number of convertible notes payable | item				250
Debt instrument face amount or principal amount	$ 25,000,000				$ 25,000,000	$ 25,000,000				$ 25,000,000		$ 25,000,000
Cash proceeds from Notes payable and warrants				$ 25,000,000
Convertible notes payable	$ 50,937,000				$ 50,937,000	50,937,000				50,937,000		$ 66,655,000
Interest on convertible notes payable						$ 544,000		$ 505,000		$ 1,081,000	$ 1,011,000
2014 Notes | Warrants to purchase common stock
Change in fair value of warrants			$ 8,957,000
Convertible Notes Payable
Repurchase of common stock, shares | shares										1,732,260
Convertible rate into common stock | $ / shares	$ 7.212				$ 7.212	$ 7.212				$ 7.212
Repurchase of common stock, value										$ 12,493,000
Convertible Notes Payable | 2017 Notes
Number of convertible notes payable | item	133	338
Debt instrument face amount or principal amount	$ 100,000	$ 100,000			$ 100,000	$ 100,000				$ 100,000
Cash proceeds from Notes payable and warrants					$ 47,100,000
Convertible rate into common stock | $ / shares	$ 8.655				$ 8.655	$ 8.655				$ 8.655
Transaction costs										$ 2,115,000
Net cash proceeds, before transaction costs										$ 32,492,000
Number of converted shares of common stock | shares										5,441,941
Convertible maturity term										5 years
Interest rate (as a percent) accrued on notes	8.00%				8.00%	8.00%				8.00%
Redemption date of notes										Nov. 4, 2019
Number of days written notice for redemption										30 days
Convertible notes payable	$ 6,259,000				$ 6,259,000	$ 6,259,000				$ 6,259,000
Gain (loss) on change in fair value of convertible notes payable and warrant liability					(113,000)
Interest on convertible notes payable					474,000
Convertible notes payable and warrants	$ 47,620,000				47,620,000	$ 47,620,000				$ 47,620,000
Loss on issuance of convertible notes payable and warrants					$ (520,000)
Convertible Notes Payable | 2017 Notes | Minimum
Convertible rate into common stock | $ / shares	$ 7.212				$ 7.212	$ 7.212				$ 7.212
Convertible Notes Payable | 2014 Notes
Debt instrument face amount or principal amount				$ 100,000
Convertible rate into common stock | $ / shares				$ 2.17275
Number of converted shares of common stock | shares				11,506,155
Interest rate (as a percent) accrued on notes				7.54%
Gain (loss) on change in fair value of convertible notes payable and warrant liability							$ (15,718,000)		$ 29,798,000
Notes, maturity date				Nov. 14, 2019

Balance Sheet Details (Details)

Balance Sheet Details (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property and Equipment:
Property and equipment, gross	$ 9,179	$ 9,671
Accumulated depreciation and amortization	(7,279)	(7,394)
Property and equipment, net	1,900	2,277
Accrued Expenses and Other Current Liabilities:
Accrued salaries and other employee costs	836	1,456
Accrued operating expenses	481	519
Accrued use taxes and other	113	198
Accrued expenses and other current liabilities, total	1,430	2,173
Furniture, office equipment, and software
Property and Equipment:
Property and equipment, gross	655	655
Laboratory equipment
Property and Equipment:
Property and equipment, gross	6,112	6,604
Leasehold improvements
Property and Equipment:
Property and equipment, gross	$ 2,412	$ 2,412

Income Taxes (Details)

Income Taxes (Details)	6 Months Ended
	Jun. 30, 2017USD ($)
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 0
Deferred tax assets	0
Deferred tax liability	$ 0

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($)

Jan. 01, 2017

May 31, 2017

Mar. 31, 2017

Jul. 31, 2016

May 31, 2016

Mar. 31, 2015

May 31, 2013

Jan. 31, 2013

Jun. 30, 2017

Mar. 31, 2016

Jun. 30, 2017

Jun. 30, 2016

Dec. 31, 2016

Stock-Based Compensation

Options, granted (in shares)

474,600

570,100

Total cancelled (in shares)

6,980

106,834

Performance-based awards

Stock-Based Compensation

Vesting periods

9 months

12 months

Vesting percentage

65.00%

Options, granted (in shares)

316,000

Total cancelled (in shares)

0

12,250

Stock-based compensation expense

$ 128,000

$ 344,000

$ 208,000

Equity awards to employees

Stock-Based Compensation

Term of options granted under the plan

10 years

Percentage of volatility upward adjustment

10.00%

Period considered for historical market prices

6 years 6 months

Dividend yield (as a percent)

0.00%

Weighted average grant date fair value (in dollars per share)

$ 4.70

Intrinsic value of options exercised

$ 0

$ 92,000

2010 Equity Incentive Plan

Stock-Based Compensation

Number of shares added in reserve

1,285,544

Total number of shares in reserve with additional shares under the Plan

9,266,190

9,266,190

Employee share of common stock upon exercise or vesting

1

Vesting periods

4 years

Tax benefits from stock based compensation

$ 0

2010 Equity Incentive Plan | Share-based Compensation Award, Tranche One

Stock-Based Compensation

Vesting percentage

25.00%

2010 Equity Incentive Plan | Share-based Compensation Award, Tranche Two

Stock-Based Compensation

Vesting percentage

75.00%

2010 Equity Incentive Plan | Restricted stock

Stock-Based Compensation

Annual vesting percent

25.00%

25.00%

Shares of restricted stock awarded

47,500

40,000

Shares cancelled

0

2010 Equity Incentive Plan | RSUs

Stock-Based Compensation

Vesting percentage

33.33%

Shares cancelled

0

118,000

Number of shares awarded

29,250

175,550

12,600

35,200

824,200

Shares of restricted stock vested

0

Maximum | Performance-based awards

Stock-Based Compensation

Vesting periods

30 months

Maximum | 2010 Equity Incentive Plan

Stock-Based Compensation

Increment in the number of shares reserved under the Plan annually (as a percent)

3.00%

Term of options granted under the plan

10 years

Maximum | 2010 Equity Incentive Plan | RSUs

Stock-Based Compensation

Vesting periods

30 months

Minimum | Performance-based awards

Stock-Based Compensation

Vesting periods

9 months

Minimum | 2010 Equity Incentive Plan | RSUs

Stock-Based Compensation

Vesting periods

21 months

Weighted Average | 2010 Equity Incentive Plan | RSUs

Stock-Based Compensation

Vesting periods

10 months 3 days

8 months 3 days

Stock-Based Compensation (Det29

Stock-Based Compensation (Details 1) - $ / shares	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Options Outstanding
Balance at the beginning of period (in shares)	6,128,192	5,912,425
Granted (in shares)	474,600	570,100
Cancelled (in shares)	(6,980)	(106,834)
Exercised (in shares)		(247,499)
Balance at the end of period (in shares)	6,595,812	6,128,192
Weighted Average Exercise Price
Balance at the beginning of period (in dollars per share)	$ 6.65	$ 6.46
Granted (in dollars per share)	7.60	8.22
Cancelled (in dollars per share)	5.95	10.81
Exercised (in dollars per share)		4.04
Balance at the end of period (in dollars per share)	$ 6.72	$ 6.65

Stock-Based Compensation (Det30

Stock-Based Compensation (Details 2) - Equity awards to employees - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Employee Stock-Based Compensation:
Total stock-based compensation	$ 977	$ 1,875	$ 1,889	$ 3,030
Research and development expense
Employee Stock-Based Compensation:
Total stock-based compensation	184	800	346	1,164
Selling, general, and administrative expense
Employee Stock-Based Compensation:
Total stock-based compensation	$ 793	$ 1,075	$ 1,543	$ 1,866

Stock-Based Compensation (Det31

Stock-Based Compensation (Details 3) - Employee Stock Option	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Additional information related to fair values of options granted
Risk-free interest rate (as a percent)	2.30%	1.60%
Expected volatility of common stock (as a percent)	66.10%	57.50%
Expected life	6 years 3 months	6 years 2 months 1 day
Dividend yield (as a percent)	0.00%	0.00%

Commitments and Contingencies (

Commitments and Contingencies (Details)	6 Months Ended
	Jun. 30, 2017USD ($)$ / item
Commitment And Contingencies [Line Items]
Annual licensing payment	$ 175,000
Other payments of royalty agreement occur during commercialization	950,000
Contingent license fee payable only upon a change in ownership of licensee	$ 350,000
Minimum
Commitment And Contingencies [Line Items]
Royalty payment per unit (in dollar per unit) | $ / item	15
Maximum
Commitment And Contingencies [Line Items]
Royalty payment per unit (in dollar per unit) | $ / item	50
License provisions for escalating minimum royalties	$ 2,200,000
Milestone amounts paid to the licensors (as a percent)	40.00%
Annual payments to extend filing periods related to certain technology	$ 300,000
Expected annual deferred payments to extend filing periods related to certain technology	$ 250,000

Net Income (Loss) Per Common 33

Net Income (Loss) Per Common Share (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Diluted Net Loss:
Net income (loss) used for basic net income (loss) per share	$ (503)	$ (4,555)	$ 921	$ (45,353)
Interest expense on convertible notes payable			1,081
Gain on change in fair value of convertible notes payable			(15,718)
Diluted Net Loss	$ (503)	$ (4,555)	$ (13,716)	$ (45,353)
Weighted Average Shares Used to Compute Diluted Net Loss per Share:
Shares used for basic net income (loss) per share	41,988,220	42,569,166	42,410,841	41,520,092
Common share equivalents			11,506,156
Weighted Average Shares Used to Compute Diluted Net Loss Per Share	41,988,220	42,569,166	53,916,997	41,520,092

Net Income (Loss) Per Common 34

Net Income (Loss) Per Common Share (Details 1) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Weighted Average Shares Excluded from EPS:
Total weighted average shares excluded	22,813,536	18,890,402	20,659,014	19,814,419
Options to purchase common stock
Weighted Average Shares Excluded from EPS:
Total weighted average shares excluded	6,565,952	6,414,854	6,375,868	6,300,137
Unvested restricted stock
Weighted Average Shares Excluded from EPS:
Total weighted average shares excluded	7,569	37,693	10,428	40,562
Restricted stock units
Weighted Average Shares Excluded from EPS:
Total weighted average shares excluded	923,411	931,699	850,813	957,949
Warrants to purchase common stock
Weighted Average Shares Excluded from EPS:
Total weighted average shares excluded	1,068,083		536,991	1,009,615
Common share equivalents from convertible notes
Weighted Average Shares Excluded from EPS:
Total weighted average shares excluded	14,248,521	11,506,156	12,884,914	11,506,156

Subsequent Events (Details)

Subsequent Events (Details) - Transitions from Research and Development Activities to Commercial Operations	Sep. 30, 2017USD ($)	Jul. 13, 2017Position	Sep. 30, 2017USD ($)	Mar. 31, 2018USD ($)
Subsequent Event | Executive
Subsequent Event [Line Items]
Number of positions retired and terminated | Position		2
Subsequent Event | Employee
Subsequent Event [Line Items]
Number of positions retired and terminated | Position		10
Scenario, Forecast
Subsequent Event [Line Items]
Severance expense | $	$ 300,000		$ 570,000	$ 270,000
Reversal of stock compensation expense related to unvested forfeits | $			$ 1,817,000