InVivo Therapeutics (NVIVQ) 10-K 11 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Mar. 05, 2015	Jun. 30, 2014
Document and Entity Information
Entity Registrant Name	INVIVO THERAPEUTICS HOLDINGS CORP.
Entity Central Index Key	1292519
Document Type	10-K
Document Period End Date	31-Dec-14
Amendment Flag	FALSE
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$97,155,701
Entity Common Stock, Shares Outstanding		102,410,850
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$13,459	$13,980
Restricted cash	422	602
Prepaid expenses and other current assets	1,072	20
Total current assets	14,953	14,602
Property and equipment, net	1,605	2,337
Other assets	135	157
Total assets	16,693	17,096
Current liabilities:
Accounts payable	569	899
Loan payable-current portion	320
Note payable-current portion	18	74
Capital lease payable		3
Derivative warrant liability	7,224	0
Accrued expenses	1,044	1,292
Total current liabilities	9,175	2,268
Loan payable-less current portion	1,600	1,920
Note payable-less current portion		18
Total liabilities	10,775	4,206
Commitments and contingencies
Stockholders' equity:
Common stock, $0.00001 par value, authorized 200,000,000 shares; issued and outstanding 93,812,000 and 78,773,736 shares at December 31, 2014 and 2013, respectively	1	1
Additional paid-in capital	106,172	94,798
Accumulated deficit	-100,255	-81,909
Total stockholders' equity	5,918	12,890
Total liabilities and stockholders' equity	$16,693	$17,096

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Consolidated Balance Sheets
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, authorized	200,000,000	200,000,000
Common stock, issued	93,812,000	78,773,736
Common stock, outstanding	93,812,000	78,773,736

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating expenses:
Research and development	$10,273	$10,533	$6,376
General and administrative	7,566	8,472	6,403
Total operating expenses	17,839	19,005	12,779
Operating lossl	-17,839	-19,005	-12,779
Other income (expense):
Interest income	5	15	35
Interest expense	-136	-130	-72
Modification of warrants		-765
Derivatives gain (loss)	-376	-18,871	17,480
Other income (expense), net	-507	-19,751	17,443
Net income (loss)	($18,346)	($38,756)	$4,664
Net income (loss) per share, basic (in dollars per share)	($0.21)	($0.52)	$0.07
Net income (loss) per share, diluted (in dollars per share)	($0.21)	($0.52)	$0.06
Weighted average number of common shares outstanding, basic (in shares)	88,323,044	73,991,686	63,226,899
Weighted average number of common shares outstanding, diluted (in shares)	88,323,044	73,991,686	71,919,419

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Stockholders' Equity (Deficit) (USD $)	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Total
In Thousands, except Share data
Beginning Balance at Dec. 31, 2011	$1	$16,657	($47,817)	($31,159)
Beginning Balance, (in shares) at Dec. 31, 2011	53,760,471
Share-based compensation expense		1,233		1,233
Issuance of common stock in public offering		18,155		18,155
Issuance of stock (in shares)	9,523,810
Issuance of stock for services		25		25
Issuance of stock for services (in shares)	15,000
Issuance of common stock upon exercise of warrants		1,129		1,129
Issuance of stock upon exercise of warrants (in shares)	1,779,716
Issuance of common stock upon exercise of stock options		111		111
Issuance of stock upon exercise of stock options (in shares)	755,020
Issuance of stock to 401(k) plan (in dollars)		91		91
Issuance of stock to 401(k) plan (in shares)	47,105
Fair value of warrants issued for services		32		32
Fair value of derivative warrant liability reclassified to additional paid-in capital		3,409		3,409
Net income (loss)			4,664	4,664
Ending Balance at Dec. 31, 2012	1	40,842	-43,153	-2,310
Ending Balance, (in shares) at Dec. 31, 2012	65,881,122
Share-based compensation expense		3,136		3,136
Issuance of common stock upon exercise of warrants		15,952		15,952
Issuance of stock upon exercise of warrants (in shares)	12,224,846
Issuance of common stock upon exercise of stock options		455		455
Issuance of stock upon exercise of stock options (in shares)	588,884
Issuance of stock to 401(k) plan (in dollars)		192		192
Issuance of stock to 401(k) plan (in shares)	78,884
Fair value of derivative warrant liability reclassified to additional paid-in capital		33,456		33,456
Incremental fair value from warrant modification		765		765
Net income (loss)			-38,756	-38,756
Ending Balance at Dec. 31, 2013	1	94,798	-81,909	12,890
Ending Balance, (in shares) at Dec. 31, 2013	78,773,736
Share-based compensation expense		2,730		2,730
Issuance of common stock in public offering		7,770		7,770
Issuance of stock (in shares)	14,001,250
Issuance of stock for services		477		477
Issuance of stock for services (in shares)	298,505
Issuance of common stock upon exercise of warrants		12		12
Issuance of stock upon exercise of warrants (in shares)	39,900
Issuance of common stock upon exercise of stock options		212		212
Issuance of stock upon exercise of stock options (in shares)	531,598
Issuance of stock to 401(k) plan (in dollars)		173		173
Issuance of stock to 401(k) plan (in shares)	167,011
Net income (loss)			-18,346	-18,346
Ending Balance at Dec. 31, 2014	$1	$106,172	($100,255)	$5,918
Ending Balance, (in shares) at Dec. 31, 2014	93,812,000

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net income (loss)	($18,346)	($38,756)	$4,664
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization expense	752	740	367
Non-cash derivative (gain) losses	376	18,871	-17,480
Non-cash interest expense			22
Non-cash loss from modification of warrants		765
Common stock issued to 401(k) plan	173	192	92
Common stock issued for services	477		25
Share-based compensation expense	2,730	3,136	1,233
Changes in operating assets and liabilities:
Restricted cash	180		-54
Prepaid expenses	-363	124	-61
Insurance receivable	-689
Other assets	4	5
Accounts payable	-330	-254	585
Accrued expenses	-248	271	403
Net cash used in operating activities	-15,284	-14,906	-10,204
Cash flows from investing activities:
Non-cash disposals of property and equipment	45
Purchases of property and equipment	-47	-749	-2,141
Net cash used in investing activities	-2	-749	-2,141
Cash flows from financing activities:
Proceeds from exercise of stock options	212	456	111
Proceeds from exercise of warrants, net	12	15,952	1,129
Proceeds from issuance of note payable		150
Repayment of note payable	-56	-57
Principal payments on capital lease obligation	-21	-33	-33
Proceeds from loans payable		342	1,747
Repayment of loans payable			-303
Proceeds from issuance of common stock and warrants	14,618		18,155
Net cash provided by financing activities	14,765	16,810	20,806
Increase (Decrease) in cash and cash equivalents	-521	1,155	8,461
Cash and cash equivalents at beginning of period	13,980	12,825	4,364
Cash and cash equivalents at end of period	13,459	13,980	12,825
Supplemental disclosure of cash flow information and non-cash transactions:
Cash paid for interest	132	125	50
Fair value of warrants issued in connection with underwriting agreement	6,848
Fair value of warrants issued in connection with loan agreement			32
Reclassification of derivative warrant liability to additional paid-in capital		$33,456	$3,409

NATURE_OF_OPERATIONS

NATURE OF OPERATIONS	12 Months Ended
	Dec. 31, 2014
NATURE OF OPERATIONS
NATURE OF OPERATIONS
	1. NATURE OF OPERATIONS
	Business
	InVivo Therapeutics Corporation ("InVivo") is a pioneering biomaterials and biotechnology company with a focus on the treatment of spinal cord injuries. Its proprietary technologies incorporate intellectual property that is licensed under an exclusive, world-wide license from Boston Children's Hospital and the Massachusetts Institute of Technology, as well as intellectual property that has been developed internally in collaboration with its advisors and partners.
	Since its inception, InVivo has devoted substantially all of its efforts to business planning, research and development, recruiting management and technical staff, acquiring operating assets and raising capital.

SIGNIFICANT_ACCOUNTING_POLICIE

SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2014
SIGNIFICANT ACCOUNTING POLICIES
SIGNIFICANT ACCOUNTING POLICIES
	2. SIGNIFICANT ACCOUNTING POLICIES
	A summary of the significant accounting policies followed by the Company in the preparation of the financial statements is as follows:
	Use of estimates
	The process of preparing financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of assets and liabilities at the date of financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates and changes in estimates may occur.
	Basis of presentation and principles of consolidation
	The consolidated financial statements include the accounts of InVivo Therapeutics Holdings Corp. and its wholly-owned subsidiary, InVivo Therapeutics Corporation. All significant intercompany balances and transactions have been eliminated in consolidation.
	Cash and cash equivalents
	The Company considers only those investments that are highly liquid, readily convertible to cash, and that mature within three months from date of purchase to be cash equivalents. Marketable investments are those with original maturities in excess of three months.
	At December 31, 2014 and 2013, cash equivalents were comprised of money market funds. The Company had no marketable investments at December 31, 2014 and 2013.
	Cash and cash equivalents consist of the following:
		December 31,
		2014		2013
	Cash on deposit	$	269	$	219
	Money market fund		13,190		13,761
	Total cash and cash equivalents	$	13,459	$	13,980
	Restricted cash
	At December 31, 2014 and 2013, the restricted cash of $422 and $602, respectively, represents a $111 and $291, respectively, security deposit related to the Company's credit card account, and, for each year, a $311 standby letter of credit in favor of a landlord (see Note 17).
	Financial instruments
	The carrying amounts reported in the Company's consolidated balance sheet for cash and cash equivalents and accounts payable approximate fair value based on the short-term nature of these instruments. The carrying value of note and loans payable approximates their fair value due to the market terms.
	Property and equipment
	Property and equipment are carried at cost. Depreciation and amortization expense is provided over the estimated useful lives of the assets using the straight-line method. A summary of the estimated useful lives is as follows:
	Classification	Estimated Useful Life
	Computer hardware	5 years
	Software	3 years
	Office furniture and equipment	5 years
	Research and lab equipment	5 years
	Leasehold improvements	Remaining life of lease
	Depreciation and amortization expense for the years ended December 31, 2014, 2013, and 2012 was $752, $740 and $367, respectively. Maintenance and repairs are charged to expense as incurred, while any additions or improvements are capitalized. During 2014, the Company had disposals of $47.
	Research and development expenses
	Costs incurred for research and development are expensed as incurred.
	Concentrations of credit risk
	The Company may from time to time have cash in banks in excess of FDIC insurance limits.
	Segment information
	Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision making group, in making decisions regarding resource allocation and assessing performance. To date, the Company has viewed its operations and manages its business as principally one operating segment, which is developing and commercializing biopolymer scaffolding devices for the treatment of spinal cord injuries. As of December 31, 2014 and 2013, all of the Company's assets were located in the United States.
	Income taxes
	For federal and state income taxes, deferred tax assets and liabilities are recognized based upon temporary differences between the financial statement and the tax basis of assets and liabilities. Deferred income taxes are based upon prescribed rates and enacted laws applicable to periods in which differences are expected to reverse. A valuation allowance is recorded when it is more likely than not that some portion or all of the deferred tax assets will not be realized. Accordingly, the Company provides a valuation allowance, if necessary, to reduce deferred tax assets to amounts that are realizable. Tax positions taken or expected to be taken in the course of preparing the Company's tax returns are required to be evaluated to determine whether the tax positions are "more-likely-than-not" of being sustained by the applicable tax authority.
	Tax positions not deemed to meet a more-likely-than-not threshold would be recorded as a tax expense in the current year. There were no uncertain tax positions that require accrual or disclosure to the financial statements as of December 31, 2014 or 2013. Tax years subsequent to 2010 remain open to examination by U.S. federal and state tax authorities.
	Impairment of long-lived assets
	The Company continually monitors events and changes in circumstances that could indicate that carrying amounts of long-lived assets may not be recoverable. An impairment loss is recognized when expected cash flows are less than an asset's carrying value. Accordingly, when indicators of impairment are present, the Company evaluates the carrying value of such assets in relation to the operating performance and future undiscounted cash flows of the underlying assets. The Company's policy is to record an impairment loss when it is determined that the carrying value of the asset may not be recoverable. No impairment charges were recorded for the years ended December 31, 2014, 2013 and 2012.
	Share-based payments
	The Company recognizes compensation costs resulting from the issuance of stock-based awards to employees, non-employees and directors as an expense in the Company's statement of operations over the service period based on a measurement of fair value for each stock-based award. The fair value of each option grant is estimated as of the date of grant using the Black-Scholes option-pricing model. The fair value is amortized as compensation cost on a straight-line basis over the requisite service period of the awards, which is generally the vesting period.
	Derivative instruments
	The Company generally does not use derivative instruments to hedge exposures to cash-flow or market risks; however, certain warrants to purchase Common Stock that do not meet the requirements for classification as equity are classified as liabilities. In such instances, net-cash settlement is assumed for financial reporting purposes, even when the terms of the underlying contracts do not provide for a net-cash settlement. Such financial instruments are initially recorded at fair value with subsequent changes in fair value charged (credited) to operations in each reporting period. If these instruments subsequently meet the requirements for classification as equity, the Company reclassifies the fair value to equity.
	Net income (loss) per common share
	Basic net income (loss) per share of Common Stock has been computed by dividing net income (loss) by the weighted average number of shares outstanding during the period. Diluted net income per share of Common Stock has been computed by dividing net income by the weighted average number of shares outstanding plus the dilutive effect, if any, of outstanding stock options, warrants and convertible securities. Diluted net loss per share of Common Stock has been computed by dividing the net loss for the period by the weighted average number of shares of Common Stock outstanding during such period. In a net loss period, options, warrants and convertible securities are anti-dilutive and therefore excluded from diluted loss per share calculations.
	Recent accounting pronouncements
	In June 2014, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update ("ASU") 2014-10, "Development Stage Entities", Topic 915. The objective of the ASU is to improve financial reporting by reducing the cost and complexity associated with the incremental reporting requirements for development stage entities. The ASU removes Topic 915, Development Stage Entities in its entirety from FASB Accounting Standards Codification ("ASC"). The ASU removes all incremental financial reporting requirements from U.S. GAAP for development stage entities, including the inception-to-date information and certain other disclosures. It also eliminates the guidance in ASC 810 on how to assess whether a development stage entity has sufficient equity at risk in the evaluation of whether the development stage entity is a variable interest entity. Additionally, the ASU clarifies that all entities, including entities that have not begun operations, should provide the risk and uncertainty disclosures required in ASC 275. The Company has elected to early adopt as permitted by ASU 2014-10 and, therefore, has omitted inception-to-date information and certain other disclosures.

PROPERTY_AND_EQUIPMENT

PROPERTY AND EQUIPMENT	12 Months Ended
	Dec. 31, 2014
PROPERTY AND EQUIPMENT
PROPERTY AND EQUIPMENT
	3. PROPERTY AND EQUIPMENT
	Property and equipment, net consisted of the following:
		2014			2013
	Computer software and hardware	$	562		$	560
	Research and lab equipment		1,873			1,881
	Leasehold improvements		390			381
	Office Equipment		790			791
	Less accumulated depreciation and amortization		(2,010	)		(1,276	)
	Property and equipment, net	$	1,605		$	2,337

INTANGIBLE_ASSETS

INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2014
INTANGIBLE ASSETS
INTANGIBLE ASSETS
	4. INTANGIBLE ASSETS
	Intangible assets, included in "other assets," consisted of patent licensing fees paid to license intellectual property (see Note 16). The Company is amortizing the license fee as a research and development expense over the 15-year term of the license.
		2014			2013
	Patent licensing fee	$	200		$	200
	Accumulated amortization		(86	)		(69	)
		$	114		$	131
	For each of the years ended December 31, 2014, 2013, and 2012, the amortization expense was $18. Amortization expense in each of the next five years is also expected to be $18 per year.

ACCRUED_EXPENSES

ACCRUED EXPENSES	12 Months Ended
	Dec. 31, 2014
ACCRUED EXPENSES
ACCRUED EXPENSES
	5. ACCRUED EXPENSES
	Accrued expenses consisted of the following:
		December 31,
		2014		2013
	Accrued bonus	$	—	$	566
	Accrued payroll		49		101
	Deferred rent payable		505		553
	Accrued vacation		72		23
	Accrued legal		360		—
	Other accrued expenses		58		49
		$	1,044	$	1,292

NOTE_PAYABLE

NOTE PAYABLE	12 Months Ended
	Dec. 31, 2014
NOTE PAYABLE.
NOTE PAYABLE
	6. NOTE PAYABLE
	In May 2013, the Company entered into a contract for the purchase of an enterprise resource planning ("ERP") system for $150. The total cost for the ERP system, including interest, is $159, with an implicit interest rate of approximately 6%.
	Pursuant to the terms of this non-cancelable purchase agreement in effect at December 31, 2014, the future minimum principal payments are as follows:
	Year Ended December 31,
	2015		18
	Total	$	18
	In the third quarter of 2013, the Company decided to abandon the implementation of the ERP system. As such, the ERP system cost of $150 was fully expensed in 2013. The Company reserves the right to implement the ERP system at a future date.

FAIR_VALUES_OF_ASSETS_AND_LIAB

FAIR VALUES OF ASSETS AND LIABILITIES	12 Months Ended
	Dec. 31, 2014
FAIR VALUES OF ASSETS AND LIABILITIES
FAIR VALUES OF ASSETS AND LIABILITIES
	7. FAIR VALUES OF ASSETS AND LIABILITIES
	The Company groups its assets and liabilities generally measured at fair value in three levels, based on the markets in which the assets and liabilities are traded and the reliability of the assumptions used to determine fair value.
	Level 1—Valuation is based on quoted prices in active markets for identical assets or liabilities. Level 1 assets and liabilities generally include debt and equity securities that are traded in an active exchange market. Valuations are obtained from readily available pricing sources for market transactions involving identical assets or liabilities.
	Level 2—Valuation is based on observable inputs other than Level 1 prices, 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.
	Level 3—Valuation is based on unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation.
	The Company uses valuation methods and assumptions that consider among other factors the fair value of the underlying stock, risk-free interest rate, volatility, expected life and dividend rates in estimating fair value for the warrants considered to be derivative instruments.
	Assets and liabilities measured at fair value on a recurring basis are summarized below:
		At December 31, 2014
		Level 1		Level 2		Level 3		Fair Value
	Liabilities:
	Derivative warrant liability	$	—	$	7,224	$	—	$	7,224
	There were no assets or liabilities measured at fair value on a recurring basis at December 31, 2013, and there were no assets or liabilities measured at fair value on a non-recurring basis at December 31, 2014 and 2013.

CAPITAL_LEASE_PAYABLE

CAPITAL LEASE PAYABLE	12 Months Ended
	Dec. 31, 2014
CAPITAL LEASE PAYABLE
CAPITAL LEASE PAYABLE
	8. CAPITAL LEASE PAYABLE
	In February 2011, the Company entered into a capital lease agreement under which the Company leased certain laboratory equipment. Capital lease obligation consisted of the following:
		December 31,
		2014		2013
	Capital lease payable	$	—	$	3
	Less: current portion		—		(3	)
		$	—	$	—
	The total value of the laboratory equipment acquired under this capital lease agreement was $124 including a down payment of $31. The capital lease is payable in monthly installments of $3 payable over thirty-six months and the final payment was made in January 2014. For the years ended December 31, 2014 and 2013, interest expense recorded on the capital lease was $0 and $1, respectively. For each of the years ended December 31, 2014, 2013 and 2012, depreciation expense on the assets under capital lease was $25. The net book value at December 31, 2014 and 2013 amounted to $27 and $52, respectively.

LOAN_PAYABLE

LOAN PAYABLE	12 Months Ended
	Dec. 31, 2014
LOAN PAYABLE
LOAN PAYABLE
	9. LOAN PAYABLE
	In October 2012, the Company entered into a loan agreement with the Massachusetts Development Finance Agency ("MassDev"). The loan agreement provided the Company with a $2,000 line of credit from the Commonwealth of Massachusetts's Emerging Technology fund, with $200 to be used for working capital purposes and the remainder to be used for the purchase of capital equipment. The annual interest rate is fixed at 6.5% with interest-only payments for the first thirty months, commencing on November 1, 2012, and then equal interest and principal payments over the next fifty-four months, with the final maturity of the loan on October 5, 2019. Based on the $1,920 balance outstanding as of December 31, 2014, equal monthly principal payments of $36 will be due commencing on May 1, 2015. Therefore, for the years ending December 31, 2015, 2016, 2017, 2018, and 2019, principal payments of $320, $427, $426, $427, and $320, respectively, will be due. In September 2012, the Company was assessed commitment fees totaling $15, which was charged to the Company as interest expense. In October 2012, as part of the commitment fee, the Company issued MassDev a warrant for the purchase of 36,145 shares of its Common Stock. The warrant has a seven-year term and is exercisable at $1.66 per share. The fair value of the warrant was determined to be $32 and was recorded as a deferred financing cost, and is being amortized to interest expense over a seven-year period commencing in October 2012. Amortization of the deferred financing cost for the years ended December 31, 2014 and 2013 was $5, and was included in interest expense in the Company's consolidated statements of operations. The equipment line of credit is secured by substantially all the assets of the Company, excluding intellectual property. During 2013, the Company drew on the line and received proceeds of $342, for capital equipment. Interest expense related to this loan was $127 for the year ended December 31, 2014 and $120 for the year ended December 31, 2013.
	In June 2011, the Company entered into a loan agreement with a bank for a $1,000 line of credit used for the purchase of certain capital equipment. The annual interest rate was the greater of 6.75% or 3.50% above the prime rate as set forth in the agreement. Borrowings were repayable in equal monthly installments over a thirty-six month period. The Company was assessed commitment fees totaling $10 and issued the bank a warrant for the purchase of 16,071 shares of Common Stock. The warrant has a seven-year term and is exercisable at $1.40 per share. The fair value of the warrant was determined to be $10, and was recorded as a deferred financing cost that was being amortized to interest expense over the life of the loan. Under the terms of the MassDev loan disclosed above, in October 2012, the Company repaid the outstanding balance of $134 due to the bank and wrote off the remaining deferred financing costs. Amortization of deferred financing costs on this loan for the year ended December 31, 2012 was $6, and was included in interest expense. Interest expense related to the loan payable to the bank was $16 for the year ended December 31, 2012.
	At December 31, loans payable consisted of the following:
		December 31,
		2014		2013
	Equipment Loan	$	1,920	$	1,920
	Less: current portion		320		—
		$	1,600	$	1,920

INCOME_TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2014
INCOME TAXES
INCOME TAXES
	10. INCOME TAXES
	No provision or benefit for federal or state income taxes has been recorded, as the Company has incurred a net loss for all of the periods presented, and the Company has provided a full valuation allowance against its deferred tax assets.
	At December 31, 2014, the Company had U.S. federal and Massachusetts net operating loss carryforwards of $58,293 and $50,568, respectively, of which federal carryforwards will expire in varying amounts beginning in 2026. Massachusetts net operating losses began to expire in 2011. Utilization of net operating losses may be subject to substantial annual limitations due to the "change in ownership" provisions of the Internal Revenue Code, and similar state provisions. The annual limitations may result in the expiration of net operating losses before utilization. The Company also had research and development tax credit carryforwards at December 31, 2014 of $867 which will begin to expire in 2021 unless previously utilized.
	Significant components of the Company's net deferred tax asset are as follows:
		December 31,
		2014			2013
	Net operating loss carryforward	$	22,490		$	16,032
	Research and development credit carryforward		801			625
	Stock-based compensation		2,265			2,411
	Depreciation and amortization		(124	)		(149	)
	Accrued expenses		226			449
	Charitable contributions		112			112
	Subtotal		25,770			19,480
	Valuation allowance		(25,770	)		(19,480	)
	Net deferred taxes	$	—		$	—
	The Company has maintained a full valuation allowance against its deferred tax assets in all periods presented. A valuation allowance is required to be recorded when it is more likely than not that some portion or all of the net deferred tax assets will not be realized. Since the Company cannot be assured of generating taxable income and thereby realizing the net deferred tax assets, a full valuation allowance has been provided. In the years ended December 31, 2014 and 2013, the valuation allowance increased by $6,290 and $7,738, respectively.
	The Company has no uncertain tax positions at December 31, 2014 and 2013 that would affect its effective tax rate. The Company does not anticipate a significant change in the amount of uncertain tax positions over the next twelve months. Since the Company is in a loss carryforward position, the Company is generally subject to U.S. federal and state income tax examinations by tax authorities for all years for which a loss carryforward is available.
	Income tax benefits computed using the federal statutory income tax rate differs from the Company's effective tax rate primarily due to the following:
		December 31,
		2014			2013			2012
	Statutory rate		(34.0	)%		(34.0	)%		34.0	%
	State taxes, net of benefit		(4.8	)%		(2.6	)%		(14.2	)%
	Permanent differences:
	Derivative losses		0.7	%		17.1	%		(127.4	)%
	Other		2.6	%		0.0	%		(1.9	)%
	R&D tax credit		(1.0	)%		(0.4	)%		7.0	%
	True up, past year		2.2	%		0.0	%		0.0	%
	Increase in valuation reserve		34.3	%		19.9	%		102.5	%
	Effective tax rate		0.0	%		0.0	%		0.0	%

COMMON_STOCK

COMMON STOCK	12 Months Ended
	Dec. 31, 2014
COMMON STOCK.
COMMON STOCK
	11. COMMON STOCK
	The Company has authorized 200,000,000 shares of Common Stock, $0.00001 par value per share, of which 93,812,000, shares were issued and outstanding as of December 31, 2014 and 78,773,736 shares were issued and outstanding as of December 31, 2013.
	During the year ended December 31, 2014, the Company issued an aggregate of 531,598 shares of Common Stock upon the exercise of stock options and received cash proceeds of $212.
	During the year ended December 31, 2014, the Company issued an aggregate of 39,900 shares of Common Stock upon the exercise of warrants, including warrants to purchase 62,620 shares of Common Stock exercised through cashless exercise provisions resulting in the issuance of 27,610 shares of common stock and warrants to purchase 12,290 shares of Common Stock exercised for cash, providing cash proceeds of $12.
	During the year ended December 31, 2014, the Company issued an aggregate of 167,011 shares of Common Stock with a fair value of $173 to the Company's 401(k) plan as a matching contribution.
	In January 2014, the Company issued 108,848 and 22,374 shares of Common Stock to Michael J. Astrue, the Company's then-Interim Chief Executive Officer, and Gregory D. Perry, the Company's then-Interim Chief Financial Officer, respectively, in lieu of executive cash bonuses. Such shares had an aggregate fair value of approximately $282.
	In December 2014, the Company issued 167,283 shares of Common Stock to certain employees of the Company in lieu of cash bonuses. Such shares had an aggregate fair value of approximately $195.
	During the year ended December 31, 2014, the Company closed an underwritten public offering of an aggregate of 14,001,250 shares of common stock and warrants to purchase up to an aggregate of 7,000,625 shares of common stock, at a price to the public of $1.15 per share of common stock and $0.00001 per warrant. The net proceeds to the Company, after deducting underwriting discounts and offering expenses, were approximately $14,600. The warrants have a per share price of $1.4375, or 125% of the public offering of the common stock, and expire on May 9, 2019.
	During the year ended December 31, 2013, the Company issued an aggregate of 588,884 shares of Common Stock upon the exercise of stock options and received cash proceeds of $456.
	During the year ended December 31, 2013, the Company issued an aggregate of 12,224,846 shares of Common Stock upon the exercise of warrants, including warrants to purchase 627,036 shares of Common Stock exercised through cashless exercise provisions and warrants to purchase 11,813,334 shares of Common Stock exercised for cash, providing cash proceeds of $15,952.
	During the year ended December 31, 2012, the Company issued 15,000 unregistered shares of Common Stock with a fair value of $25 to an investor relations firm in exchange for services provided.
	During the year ended December 31, 2012, the Company issued an aggregate of 755,020 shares of Common Stock upon the exercise of stock options and received cash proceeds of $111.
	During the year ended December 31, 2012, the Company issued an aggregate of 1,779,716 shares of Common Stock upon the exercise of warrants, including warrants to purchase 1,865,670 shares of Common Stock exercised through cashless exercise provisions and warrants to purchase 852,946 shares of Common Stock exercised for cash, providing cash proceeds of $1,129.
	During the year ended December 31, 2012, the Company completed a public offering of Common Stock and issued 9,523,810 shares of its Common Stock at a purchase price of $2.10 per share. The offering raised gross proceeds of approximately $20,000, and the Company received net proceeds of $18,155, after deducting underwriter discounts and offering expenses.
	Common Stock Reserves
	As of December 31, 2014, the Company had the following reserves established for the future issuance of Common Stock as follows:
	Reserves for the exercise of warrants	10,208,849
	Reserves for the exercise of stock options	12,361,445
	Total Reserves	22,570,294

DERIVATIVE_INSTRUMENTS

DERIVATIVE INSTRUMENTS	12 Months Ended
	Dec. 31, 2014
DERIVATIVE INSTRUMENTS
DERIVATIVE INSTRUMENTS
	12. DERIVATIVE INSTRUMENTS
	Certain warrants issued to investors and the placement agent warrants in the fourth quarter of 2010 had provisions that included anti-dilution protection and, under certain conditions, granted the right to the holder to require the Company to repurchase the warrant. Accordingly through March 2013, these warrants were accounted for as derivative liabilities. In the quarter ended March 31, 2013, $476 was reclassified from Derivative warrant liability to Additional paid-in capital related to warrants exercised. In May 2013 outstanding investor warrants totaling 11,726,343 warrants, were exercised and the fair value of $25,241was reclassified from Derivative warrant liability to Additional paid-in capital.
	On May 17, 2013, the Company completed its offer to exchange certain of its outstanding warrants to purchase shares of the Company's common stock (the "Eligible Warrants") for new warrants (the "New Warrants") with the same terms except (i) the expiration date of the New Warrants was extended two years and (ii) weighted average anti-dilution provisions were removed from the New Warrants (the "Offer"). The Eligible Warrants consisted of (i) warrants to purchase common stock dated October 26, 2010, issued in connection with the closing of a merger (the "Merger Warrants") and (ii) warrants to purchase common stock issued to the placement agent as compensation for services in connection with each closing of a private placement which occurred on October 26, 2010, November 10, 2010 and December 3, 2010 (the "Placement Agent Warrants"). In connection with the Offer, Merger Warrants to purchase 255,000 shares of the Company's common stock and Placement Agent Warrants to purchase 3,064,091 shares of the Company's common stock were tendered and accepted for exchange for New Warrants to purchase an aggregate of 3,319,091 shares of the Company's common stock. Due to the modification of the terms, the Eligible Warrants were revalued prior to modification and immediately after modification as of May 17, 2013. This resulted in a non-cash charge of $765 which was recorded in Other expense as Loss from modification of warrants. Since the New Warrants are not accounted for as derivative liabilities, the fair value of these warrants after modification of $7,738 was reclassified from Derivative warrant liability to Additional paid-in capital.
	The warrants issued in connection with the May 2014 public offering to purchase 7,000,625 shares of the Common Stock (see Note 11) have anti-dilution protection provisions and, under certain conditions, grant the right to the holder to require the Company to re-price the warrant. Accordingly these warrants are accounted for as derivative liabilities. The Company used the Black-Scholes option pricing model and assumptions that consider, among other factors, the fair value of the underlying stock, risk-free interest rate, volatility, expected life and dividend rates in estimating fair value for the warrants considered to be derivative instruments. Changes in fair value of the derivative financial instruments are recognized in the Company's consolidated statement of operations as a derivative gain or loss. The warrant derivative gains (losses) are non-cash income (expenses); and for the 12 months ended December 31, 2014, 2013 and 2012, a gain (loss) of $(376) and $(18,871) and $17,480, respectively, were included in other income (expense) in the Company's consolidated statement of operations.
	The Company uses the Black-Scholes option pricing model and assumptions that consider among other factors the fair value of the underlying stock, risk -free interest rate, volatility, expected life and dividend rates in estimating fair value for the warrants considered to be derivative instruments. The fair value of these derivative instruments at December 31, 2014 and 2013 was $7,224 and $0, respectively, and was included as a derivative warrant liability, a current liability. Changes in fair value of the derivative financial instruments are recognized currently in the statement of operations as a derivative gain or loss.
	The assumptions used principally in determining the fair value of warrants were as follows:
		Year Ended December 31,
		2014		2013			2012
	Risk free interest rate	1.47%			N/A		0.32 - 0.35%
	Expected dividend yield	0%			N/A		0%
	Contractual term	4.4 years			N/A		2.7 - 2.9 years
	Expected volatility	119%			N/A		73%
	The primary underlying risk exposure pertaining to the warrants is the change in fair value of the underlying Common Stock for each reporting period.
	The table below presents the changes in derivative warrant liability during the years ended December 31, 2014, 2013, and 2012:
		Year Ended December 31,
		2014			2013			2012
	Balance at beginning of year	$	—		$	14,585		$	35,473
	Issuance of warrants		6,848			—			—
	Increase (decrease) in the fair value of the warrants		376			18,871			(17,480	)
	Fair value of derivative warrant liability reclassified to additional paid in capital		—			(33,456	)		(3,408	)
	Balance at end of year	$	7,224		$	—		$	14,585

STOCK_OPTIONS

STOCK OPTIONS	12 Months Ended
	Dec. 31, 2014
STOCK OPTIONS.
STOCK OPTIONS
	13. STOCK OPTIONS
	In 2007, the Company adopted the 2007 Employee, Director and Consultant Stock Plan (the "2007 Plan"). Pursuant to the 2007 Plan, the Company's Board of Directors (or committees and/or executive officers delegated by the Board of Directors) may grant incentive and nonqualified stock options to the Company's employees, officers, directors, consultants and advisors. As of December 31, 2014, an aggregate of 1,692,309 shares of Common Stock were outstanding under the 2007 Plan and no shares were available for future grants under the 2007 Plan.
	On October 26, 2010, the Company's Board of Directors adopted, and the Company's shareholders subsequently approved, the 2010 Equity Incentive Plan (as subsequently amended, the "2010 Plan"). The 2010 Plan provides for grants of incentive stock options to employees, and nonqualified stock options and restricted Common Stock to employees, consultants and non-employee directors of the Company. As of December 31, 2014, the number of shares authorized for issuance under the 2010 Plan, as amended, was 11,000,000 shares. As of December 31, 2014, an aggregate of 8,753,353 shares of Common Stock were outstanding under the 2010 Plan and 1,748,500 shares were available for future grants under the 2010 Plan.
	Options issued under the 2007 Plan and the 2010 Plan (collectively, the "Plans") are exercisable for up to 10 years from the date of issuance.
	Share-based compensation
	For stock options issued and outstanding for the years ended December 31, 2014, 2013 and 2012, the Company recorded non-cash, stock-based compensation expense of $2,730, $3,136 and $1,233, respectively, net of forfeitures.
	The fair value of each option award is estimated on the date of grant using the Black-Scholes option pricing model that uses the assumptions noted in the following table. Due to its limited operating history and limited number of sales of its Common Stock, the Company estimated its volatility in consideration of a number of factors including the volatility of comparable public companies. The Company uses historical data, as well as subsequent events occurring prior to the issuance of the financial statements, to estimate option exercises and employee terminations within the valuation model. The expected term of options granted under the Plans, all of which qualify as "plain vanilla," is based on the average of the contractual term (10 years) and the vesting period (generally, 48 months). For non-employee options, the expected term is the contractual term. The risk-free rate is based on the yield of a U.S. Treasury security with a term consistent with the option.
	The assumptions used principally in determining the fair value of options granted were as follows:
		December 31,
		2014		2013		2012
	Risk-free interest rate	1.62 - 2.06%		0.77 - 2.52%		0.62 - 1.23%
	Expected dividend yield	0%		0%		0%
	Expected term (employee grants)	6.03 years		6.25 years		6.25 years
	Expected volatility	124%		102%		75%
	A summary of option activity as of December 31, 2014 and changes for the year then ended are presented below:
	Options	Shares			Weighted		Weighted		Aggregate
					Average		Average		Intrinsic
					Exercise		Remaining		Value
					Price		Contractual
							Term in Years
	Outstanding at December 31, 2013		8,055,522		$	1.55
	Granted		4,711,250		$	1.75
	Forfeited		(1,770,948	)	$	1.86
	Exercised		(550,162	)	$	0.42
	Outstanding at December 31, 2014		10,445,662		$	1.65		7.61	$	2,569
	Vested at December 31, 2014		3,960,662		$	1.28		5.16	$	1,986
	The weighted average grant-date fair value of options granted during years ended December 31, 2014, 2013 and 2012 was $1.54, $2.04, and $1.28 per share, respectively. The total fair value of options that vested in years ended December 31, 2014, 2013, and 2012 was $2,329, $1,985 and $1,186, respectively. As of December 31, 2014, there was $5,750 of total unrecognized compensation expense, related to non-vested share-based option compensation arrangements. The unrecognized compensation expense is estimated to be recognized over a period of 2.91 years at December 31, 2014.

WARRANTS

WARRANTS	12 Months Ended
	Dec. 31, 2014
WARRANTS.
WARRANTS
	14. WARRANTS
	The following table presents information about warrants to purchase Common Stock issued and outstanding at December 31, 2014:
	Year Issued	Classification	Number of		Exercise		Date of Expiration
			Warrants		Price
	2010	Equity		1,494,603	$	1.40	10/26/2017 - 12/3/2017
	2010	Equity		1,318,268	$	1.00	9/26/2015 - 12/3/2015
	2011	Equity		16,071	$	1.40	6/17/18
	2011	Equity		343,137	$	3.06	12/21/16
	2012	Equity		36,145	$	1.66	10/5/19
	2014	Liability		7,000,625	$	1.44	5/9/19
	Total			10,208,849
	Weighted average exercise price				$	1.43
	Weighted average life in years						3.81

EMPLOYEE_BENEFIT_PLAN

EMPLOYEE BENEFIT PLAN	12 Months Ended
	Dec. 31, 2014
EMPLOYEE BENEFIT PLAN
EMPLOYEE BENEFIT PLAN
	15. EMPLOYEE BENEFIT PLAN
	In November 2006, the Company adopted a 401(k) plan (the "Plan") covering all employees. Employees must be 21 years of age in order to participate in the Plan. Under the Plan, the Company has the option to make matching contributions. For the years ended December 31, 2014, 2013 and 2012, the Company made matching contributions in the form of shares of Common Stock. For the years ended December 31, 2014, 2013, and 2012, the Company issued 167,011, 78,884, and 47,105 shares of Common Stock, respectively, with related fair values of $173, $192, and $92, respectively, were recorded as expense in the statement of operations.

INTELLECTUAL_PROPERTY_LICENSE

INTELLECTUAL PROPERTY LICENSE	12 Months Ended
	Dec. 31, 2014
INTELLECTUAL PROPERTY LICENSE
INTELLECTUAL PROPERTY LICENSE
	16. INTELLECTUAL PROPERTY LICENSE
	In July 2007, the Company entered into a world-wide exclusive license (the "BCH License") for patents co-owned by BCH and MIT initially covering the use of biopolymers to treat spinal cord injuries, and to promote the survival and proliferation of human stem cells in the spinal cord. During 2011, the BCH License was amended, and the Company obtained additional rights for use in the field of peripheral nerve injuries. The BCH License, as amended, has a 15-year term, or as long as the life of the last expiring patent right, whichever is longer, unless terminated earlier by the licensor, under certain conditions as defined in the related license agreement. In connection with the BCH License, the Company paid an initial $75 licensing fee and is required to pay certain annual maintenance fees, milestone payments and royalties. During 2011, the Company paid $75 to expand the license and, at December 31, 2011, accrued $50 for a milestone payment. License fees and milestone payments are capitalized and total $200 at December 31, 2014 (see Note 4). Maintenance and royalty costs are expensed as incurred.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2014
COMMITMENTS AND CONTINGENCIES
COMMITMENTS AND CONTINGENCIES
	17. COMMITMENTS AND CONTINGENCIES
	Leases
	On November 30, 2011 and as amended on September 17, 2012, the Company entered into a commercial lease for 26,150 square feet of office, laboratory and manufacturing space in Cambridge, Massachusetts (as amended, the "Cambridge Lease"). The term of the Cambridge Lease is six years and three months, with one five-year extension option. The terms of the Cambridge Lease require a standby letter of credit in the amount of $311 (see Note 2).
	The Cambridge Lease contains rent holidays and rent escalation clauses. The Company recognizes rent expense on a straight-line basis over the term of the Cambridge Lease and records the difference between the amount charged to expense and the rent paid as a deferred rent liability. As of December 31, 2014, the amount of deferred rent liability is $505 and is included in accrued expenses.
	It is the Company's policy to assess whether improvements made to the space rented under operating leases should be accounted for as "lessor" or "lessee" assets. In connection with the Cambridge Lease, the Company paid for lessor assets and was not reimbursed through construction allowances. Such costs are recorded as leasehold improvements, which are amortized to rent expense over the term of the Cambridge Lease. As of December 31, 2014, such leasehold improvements totaled $390 and are $249, net of accumulated depreciation.
	Pursuant to the terms of the non-cancelable lease agreements in effect at December 31, 2014, the future minimum rent commitments are as follows:
	Year Ended December 31,
	2015	$	1,243
	2016		1,269
	2017		1,295
	2018		1,049
	Total	$	4,856
	Total rent expense for the years ended December 31, 2014, 2013, and 2012, including month-to-month leases, was $1,148, $1,125 and $758, respectively.
	On September 4, 2013, the Company entered into a legal settlement agreement for $286, in connection with the Cambridge Lease. The settlement has been included in the deferred rent liability and the benefit will be amortized over the remainder of the term of the Cambridge Lease.
	Litigation
	Lawsuit with Former Employee
	In November 2013, we filed a lawsuit against Francis Reynolds, our former Chairman, Chief Executive Officer and Chief Financial Officer, in Middlesex Superior Court, Middlesex County, Massachusetts (InVivo Therapeutics Holdings Corp. v. Reynolds, Civil Action No. 13-5004). The complaint alleges breaches of fiduciary duties, breach of contract, conversion, misappropriation of corporate assets, unjust enrichment, corporate waste, and seeks monetary damages and an accounting. The lawsuit involves approximately $500 worth of personal and/or exorbitant expenses that we allege Mr. Reynolds inappropriately caused us to pay while he was serving as our Chief Executive Officer, Chief Financial Officer, President and Chairman of our Board of Directors. On December 6, 2013, Mr. Reynolds answered the complaint, and filed counterclaims against us and our Board of Directors. The counterclaims allege two counts of breach of contract, two counts of breach of the covenant of good faith and fair-dealing, and tortious interference with a contract, and seek monetary damages and a declaratory judgment. The counterclaims involve Mr. Reynolds's allegations that we and the Board interfered with the performance of his duties under the terms of his employment agreement, and that Mr. Reynolds was entitled to additional shares upon the exercise of certain stock options. On January 9, 2014, we, along with the directors named in the counterclaims, filed our answer. The parties are currently conducting pre-trial discovery. No judgments or rulings are pending at this stage.
	Shareholder Matters and Investigations
	On July 31, 2014, a putative securities class action lawsuit was filed in the United States District Court for the District of Massachusetts, naming the Company and Mr. Reynolds, as defendants (the "Securities Class Action"). The lawsuit alleges violations of the Securities Exchange Act of 1934 in connection with allegedly false and misleading statements related to the timing and completion of the clinical study of the Company's Neuro-Spinal Scaffold. The plaintiff seeks class certification for purchasers of the Company's common stock during the period from April 5, 2013 through August 26, 2013 and unspecified damages. On December 12, 2014, the Company moved to dismiss this lawsuit, and a hearing on that motion is scheduled for March 11, 2015. The Company intends to vigorously defend the lawsuit.
	On January 23, 2015, Shawn Luger, a purported shareholder of the Company, sent the Company a letter demanding that the Board of Directors take action to remedy purported breaches of fiduciary duties allegedly related to the claimed false and misleading statements that are the subject of the Securities Class Action (the "Shareholder Demand"). The Board of Directors is currently considering this demand.
	In addition to the Securities Class Action and the Shareholder Demand, the Company has received investigation subpoenas from the Boston Regional Office of the Securities and Exchange Commission and the Massachusetts Securities Division of the Secretary of the Commonwealth of Massachusetts requesting corporate documents also concerning, among other topics, the allegations raised Securities Class Action and the Shareholder Demand. The Company is currently cooperating with these investigations.

INSURANCE_CLAIM

INSURANCE CLAIM	12 Months Ended
	Dec. 31, 2014
INSURANCE CLAIM
INSURANCE CLAIM	18. INSURANCE CLAIM
	During the year ended December 31, 2014, the Company settled an insurance claim of $621 for business interruption that covered the disruption of the Company's operations at its facility in Cambridge, Massachusetts caused by water damage that occurred in September 2014. The insurance settlement reimburses the Company for costs incurred as a result of the disruption and is included as reduction of research and development expense in the consolidated statement of operations for the year ended December 31, 2014. The settlement receivable is included in other current asset in the 2014 financial statements.
	During the year ended December 31, 2013, the Company received insurance proceeds of approximately $1,100 from the settlement of a business interruption claim that covered the disruption of the Company's operations at its facility in Cambridge, Massachusetts caused by water damage that occurred in November 2012. The insurance settlement reimbursed the Company for costs incurred as a result of the disruption is included as reduction of research and development expense in the consolidated statement of operations for the year ended December 31, 2013.

SUBSEQUENT_EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	Dec. 31, 2014
SUBSEQUENT EVENTS
SUBSEQUENT EVENTS	19. SUBSEQUENT EVENTS
	In January 2015, the Company closed a registered direct offering of an aggregate of 8 million shares of common stock, resulting in net proceeds of approximately $11,000.

SIGNIFICANT_ACCOUNTING_POLICIE1

SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2014
SIGNIFICANT ACCOUNTING POLICIES
Use of estimates
	Use of estimates
	The process of preparing financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of assets and liabilities at the date of financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates and changes in estimates may occur.
Principles of consolidation
	Basis of presentation and principles of consolidation
	The consolidated financial statements include the accounts of InVivo Therapeutics Holdings Corp. and its wholly-owned subsidiary, InVivo Therapeutics Corporation. All significant intercompany balances and transactions have been eliminated in consolidation.
Cash and cash equivalents
	Cash and cash equivalents
	The Company considers only those investments that are highly liquid, readily convertible to cash, and that mature within three months from date of purchase to be cash equivalents. Marketable investments are those with original maturities in excess of three months.
	At December 31, 2014 and 2013, cash equivalents were comprised of money market funds. The Company had no marketable investments at December 31, 2014 and 2013.
	Cash and cash equivalents consist of the following:
		December 31,
		2014		2013
	Cash on deposit	$	269	$	219
	Money market fund		13,190		13,761
	Total cash and cash equivalents	$	13,459	$	13,980
Restricted cash	Restricted cash
	At December 31, 2014 and 2013, the restricted cash of $422 and $602, respectively, represents a $111 and $291, respectively, security deposit related to the Company's credit card account, and, for each year, a $311 standby letter of credit in favor of a landlord (see Note 17).
Financial instruments
	Financial instruments
	The carrying amounts reported in the Company's consolidated balance sheet for cash and cash equivalents and accounts payable approximate fair value based on the short-term nature of these instruments. The carrying value of note and loans payable approximates their fair value due to the market terms.
Property and equipment
	Property and equipment
	Property and equipment are carried at cost. Depreciation and amortization expense is provided over the estimated useful lives of the assets using the straight-line method. A summary of the estimated useful lives is as follows:
	Classification	Estimated Useful Life
	Computer hardware	5 years
	Software	3 years
	Office furniture and equipment	5 years
	Research and lab equipment	5 years
	Leasehold improvements	Remaining life of lease
	Depreciation and amortization expense for the years ended December 31, 2014, 2013, and 2012 was $752, $740 and $367, respectively. Maintenance and repairs are charged to expense as incurred, while any additions or improvements are capitalized. During 2014, the Company had disposals of $47.
Research and development expenses
	Research and development expenses
	Costs incurred for research and development are expensed as incurred.
Concentrations of credit risk
	Concentrations of credit risk
	The Company may from time to time have cash in banks in excess of FDIC insurance limits.
Segment information
	Segment information
	Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision making group, in making decisions regarding resource allocation and assessing performance. To date, the Company has viewed its operations and manages its business as principally one operating segment, which is developing and commercializing biopolymer scaffolding devices for the treatment of spinal cord injuries. As of December 31, 2014 and 2013, all of the Company's assets were located in the United States.
Income taxes
	Income taxes
	For federal and state income taxes, deferred tax assets and liabilities are recognized based upon temporary differences between the financial statement and the tax basis of assets and liabilities. Deferred income taxes are based upon prescribed rates and enacted laws applicable to periods in which differences are expected to reverse. A valuation allowance is recorded when it is more likely than not that some portion or all of the deferred tax assets will not be realized. Accordingly, the Company provides a valuation allowance, if necessary, to reduce deferred tax assets to amounts that are realizable. Tax positions taken or expected to be taken in the course of preparing the Company's tax returns are required to be evaluated to determine whether the tax positions are "more-likely-than-not" of being sustained by the applicable tax authority.
	Tax positions not deemed to meet a more-likely-than-not threshold would be recorded as a tax expense in the current year. There were no uncertain tax positions that require accrual or disclosure to the financial statements as of December 31, 2014 or 2013. Tax years subsequent to 2010 remain open to examination by U.S. federal and state tax authorities.
Impairment of long-lived assets
	Impairment of long-lived assets
	The Company continually monitors events and changes in circumstances that could indicate that carrying amounts of long-lived assets may not be recoverable. An impairment loss is recognized when expected cash flows are less than an asset's carrying value. Accordingly, when indicators of impairment are present, the Company evaluates the carrying value of such assets in relation to the operating performance and future undiscounted cash flows of the underlying assets. The Company's policy is to record an impairment loss when it is determined that the carrying value of the asset may not be recoverable. No impairment charges were recorded for the years ended December 31, 2014, 2013 and 2012.
Share-based payments
	Share-based payments
	The Company recognizes compensation costs resulting from the issuance of stock-based awards to employees, non-employees and directors as an expense in the Company's statement of operations over the service period based on a measurement of fair value for each stock-based award. The fair value of each option grant is estimated as of the date of grant using the Black-Scholes option-pricing model. The fair value is amortized as compensation cost on a straight-line basis over the requisite service period of the awards, which is generally the vesting period.
Derivative instruments
	Derivative instruments
	The Company generally does not use derivative instruments to hedge exposures to cash-flow or market risks; however, certain warrants to purchase Common Stock that do not meet the requirements for classification as equity are classified as liabilities. In such instances, net-cash settlement is assumed for financial reporting purposes, even when the terms of the underlying contracts do not provide for a net-cash settlement. Such financial instruments are initially recorded at fair value with subsequent changes in fair value charged (credited) to operations in each reporting period. If these instruments subsequently meet the requirements for classification as equity, the Company reclassifies the fair value to equity.
Net income (loss) per common share
	Net income (loss) per common share
	Basic net income (loss) per share of Common Stock has been computed by dividing net income (loss) by the weighted average number of shares outstanding during the period. Diluted net income per share of Common Stock has been computed by dividing net income by the weighted average number of shares outstanding plus the dilutive effect, if any, of outstanding stock options, warrants and convertible securities. Diluted net loss per share of Common Stock has been computed by dividing the net loss for the period by the weighted average number of shares of Common Stock outstanding during such period. In a net loss period, options, warrants and convertible securities are anti-dilutive and therefore excluded from diluted loss per share calculations.
Recent accounting pronouncements
	Recent accounting pronouncements
	In June 2014, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update ("ASU") 2014-10, "Development Stage Entities", Topic 915. The objective of the ASU is to improve financial reporting by reducing the cost and complexity associated with the incremental reporting requirements for development stage entities. The ASU removes Topic 915, Development Stage Entities in its entirety from FASB Accounting Standards Codification ("ASC"). The ASU removes all incremental financial reporting requirements from U.S. GAAP for development stage entities, including the inception-to-date information and certain other disclosures. It also eliminates the guidance in ASC 810 on how to assess whether a development stage entity has sufficient equity at risk in the evaluation of whether the development stage entity is a variable interest entity. Additionally, the ASU clarifies that all entities, including entities that have not begun operations, should provide the risk and uncertainty disclosures required in ASC 275. The Company has elected to early adopt as permitted by ASU 2014-10 and, therefore, has omitted inception-to-date information and certain other disclosures.

SIGNIFICANT_ACCOUNTING_POLICIE2

SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2014
SIGNIFICANT ACCOUNTING POLICIES
Schedule of cash and cash equivalents
		December 31,
		2014		2013
	Cash on deposit	$	269	$	219
	Money market fund		13,190		13,761
	Total cash and cash equivalents	$	13,459	$	13,980
Summary of estimated useful lives
	Classification	Estimated Useful Life
	Computer hardware	5 years
	Software	3 years
	Office furniture and equipment	5 years
	Research and lab equipment	5 years
	Leasehold improvements	Remaining life of lease

PROPERTY_AND_EQUIPMENT_Tables

PROPERTY AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2014
PROPERTY AND EQUIPMENT
Schedule of property and equipment, net
		2014			2013
	Computer software and hardware	$	562		$	560
	Research and lab equipment		1,873			1,881
	Leasehold improvements		390			381
	Office Equipment		790			791
	Less accumulated depreciation and amortization		(2,010	)		(1,276	)
	Property and equipment, net	$	1,605		$	2,337

INTANGIBLE_ASSETS_Tables

INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2014
INTANGIBLE ASSETS
Summary of intangible assets
		2014			2013
	Patent licensing fee	$	200		$	200
	Accumulated amortization		(86	)		(69	)
		$	114		$	131

ACCRUED_EXPENSES_Tables

ACCRUED EXPENSES (Tables)	12 Months Ended
	Dec. 31, 2014
ACCRUED EXPENSES
Summary of accrued expenses
		December 31,
		2014		2013
	Accrued bonus	$	—	$	566
	Accrued payroll		49		101
	Deferred rent payable		505		553
	Accrued vacation		72		23
	Accrued legal		360		—
	Other accrued expenses		58		49
		$	1,044	$	1,292

NOTE_PAYABLE_Tables

NOTE PAYABLE (Tables)	12 Months Ended
	Dec. 31, 2014
NOTE PAYABLE.
Schedule of future minimum principal payments
	Year Ended December 31,
	2015		18
	Total	$	18

FAIR_VALUES_OF_ASSETS_AND_LIAB1

FAIR VALUES OF ASSETS AND LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2014
FAIR VALUES OF ASSETS AND LIABILITIES
Summary of assets and liabilities measured at fair value on a recurring basis
		At December 31, 2014
		Level 1		Level 2		Level 3		Fair Value
	Liabilities:
	Derivative warrant liability	$	—	$	7,224	$	—	$	7,224

CAPITAL_LEASE_PAYABLE_Tables

CAPITAL LEASE PAYABLE (Tables)	12 Months Ended
	Dec. 31, 2014
CAPITAL LEASE PAYABLE
Schedule of capital lease obligation
		December 31,
		2014		2013
	Capital lease payable	$	—	$	3
	Less: current portion		—		(3	)
		$	—	$	—

LOAN_PAYABLE_Tables

LOAN PAYABLE (Tables)	12 Months Ended
	Dec. 31, 2014
LOAN PAYABLE
Summary of loans payable
		December 31,
		2014		2013
	Equipment Loan	$	1,920	$	1,920
	Less: current portion		320		—
		$	1,600	$	1,920

INCOME_TAXES_Tables

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2014
INCOME TAXES
Schedule of significant components of net deferred tax asset
		December 31,
		2014			2013
	Net operating loss carryforward	$	22,490		$	16,032
	Research and development credit carryforward		801			625
	Stock-based compensation		2,265			2,411
	Depreciation and amortization		(124	)		(149	)
	Accrued expenses		226			449
	Charitable contributions		112			112
	Subtotal		25,770			19,480
	Valuation allowance		(25,770	)		(19,480	)
	Net deferred taxes	$	—		$	—
Schedule of income tax benefits computed using the federal statutory income tax rate differs from effective tax rate
		December 31,
		2014			2013			2012
	Statutory rate		(34.0	)%		(34.0	)%		34.0	%
	State taxes, net of benefit		(4.8	)%		(2.6	)%		(14.2	)%
	Permanent differences:
	Derivative losses		0.7	%		17.1	%		(127.4	)%
	Other		2.6	%		0.0	%		(1.9	)%
	R&D tax credit		(1.0	)%		(0.4	)%		7.0	%
	True up, past year		2.2	%		0.0	%		0.0	%
	Increase in valuation reserve		34.3	%		19.9	%		102.5	%
	Effective tax rate		0.0	%		0.0	%		0.0	%

COMMON_STOCK_Tables

COMMON STOCK (Tables)	12 Months Ended
	Dec. 31, 2014
COMMON STOCK.
Schedule of reserves established for future issuance of Common Stock
	Reserves for the exercise of warrants	10,208,849
	Reserves for the exercise of stock options	12,361,445
	Total Reserves	22,570,294

DERIVATIVE_INSTRUMENTS_Tables

DERIVATIVE INSTRUMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
DERIVATIVE INSTRUMENTS
Assumptions used in determining fair value of warrants
		Year Ended December 31,
		2014		2013			2012
	Risk free interest rate	1.47%			N/A		0.32 - 0.35%
	Expected dividend yield	0%			N/A		0%
	Contractual term	4.4 years			N/A		2.7 - 2.9 years
	Expected volatility	119%			N/A		73%
Changes in derivative warrant liability
		Year Ended December 31,
		2014			2013			2012
	Balance at beginning of year	$	—		$	14,585		$	35,473
	Issuance of warrants		6,848			—			—
	Increase (decrease) in the fair value of the warrants		376			18,871			(17,480	)
	Fair value of derivative warrant liability reclassified to additional paid in capital		—			(33,456	)		(3,408	)
	Balance at end of year	$	7,224		$	—		$	14,585

STOCK_OPTIONS_Tables

STOCK OPTIONS (Tables)	12 Months Ended
	Dec. 31, 2014
STOCK OPTIONS.
Schedule of assumptions used principally in determining the fair value of options granted
		December 31,
		2014		2013		2012
	Risk-free interest rate	1.62 - 2.06%		0.77 - 2.52%		0.62 - 1.23%
	Expected dividend yield	0%		0%		0%
	Expected term (employee grants)	6.03 years		6.25 years		6.25 years
	Expected volatility	124%		102%		75%
Summary of option activity
	Options	Shares			Weighted		Weighted		Aggregate
					Average		Average		Intrinsic
					Exercise		Remaining		Value
					Price		Contractual
							Term in Years
	Outstanding at December 31, 2013		8,055,522		$	1.55
	Granted		4,711,250		$	1.75
	Forfeited		(1,770,948	)	$	1.86
	Exercised		(550,162	)	$	0.42
	Outstanding at December 31, 2014		10,445,662		$	1.65		7.61	$	2,569
	Vested at December 31, 2014		3,960,662		$	1.28		5.16	$	1,986

WARRANTS_Tables

WARRANTS (Tables)	12 Months Ended
	Dec. 31, 2014
WARRANTS.
Schedule of information about warrants to purchase common stock issued and outstanding
	Year Issued	Classification	Number of		Exercise		Date of Expiration
			Warrants		Price
	2010	Equity		1,494,603	$	1.40	10/26/2017 - 12/3/2017
	2010	Equity		1,318,268	$	1.00	9/26/2015 - 12/3/2015
	2011	Equity		16,071	$	1.40	6/17/18
	2011	Equity		343,137	$	3.06	12/21/16
	2012	Equity		36,145	$	1.66	10/5/19
	2014	Liability		7,000,625	$	1.44	5/9/19
	Total			10,208,849
	Weighted average exercise price				$	1.43
	Weighted average life in years						3.81

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2014
COMMITMENTS AND CONTINGENCIES
Future minimum rent commitments
	Year Ended December 31,
	2015	$	1,243
	2016		1,269
	2017		1,295
	2018		1,049
	Total	$	4,856

SIGNIFICANT_ACCOUNTING_POLICIE3

SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Cash and cash equivalents
Cash and cash equivalents	$13,459	$13,980	$12,825	$4,364
Investments
Marketable investments, amount	0	0
Cash on deposit
Cash and cash equivalents
Cash and cash equivalents	269	219
Money market fund
Cash and cash equivalents
Cash and cash equivalents	$13,190	$13,761

SIGNIFICANT_ACCOUNTING_POLICIE4

SIGNIFICANT ACCOUNTING POLICIES (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Restricted cash
Restricted cash	$422	$602
Security deposit related to credit card account
Restricted cash
Restricted cash	111	291
Standby letter of credit in favor of a landlord
Restricted cash
Restricted cash	$311	$311

SIGNIFICANT_ACCOUNTING_POLICIE5

SIGNIFICANT ACCOUNTING POLICIES (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Depreciation
Depreciation expense	$752	$740	$367
Disposals	$47
Computer hardware
Property and equipment
Estimated Useful Life	5 years
Software
Property and equipment
Estimated Useful Life	3 years
Office Equipment
Property and equipment
Estimated Useful Life	5 years
Research and lab equipment
Property and equipment
Estimated Useful Life	5 years

SIGNIFICANT_ACCOUNTING_POLICIE6

SIGNIFICANT ACCOUNTING POLICIES (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	segment
SIGNIFICANT ACCOUNTING POLICIES
Number of Operating Segments	1
Uncertain tax positions amount	$0	$0
Impairment charges on long-lived assets	$0	$0	$0

PROPERTY_AND_EQUIPMENT_Details

PROPERTY AND EQUIPMENT (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property and equipment
Less accumulated depreciation and amortization	($2,010)	($1,276)
Property and equipment,net	1,605	2,337
Computer software and hardware
Property and equipment
Gross property and equipment	562	560
Research and lab equipment
Property and equipment
Gross property and equipment	1,873	1,881
Leasehold improvements
Property and equipment
Gross property and equipment	390	381
Office Equipment
Property and equipment
Gross property and equipment	$790	$791

INTANGIBLE_ASSETS_Details

INTANGIBLE ASSETS (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amortization
Amortization expense	$18	$18	$18
Future amortization
Expected amortization expense in next year	18
Expected amortization expense in second year	18
Expected amortization expense in third year	18
Expected amortization expense in fourth year	18
Expected amortization expense in fifth year	18
Patent licensing fee
Intangible assets
Useful life	15 years
Intangible assets - gross	200	200
Accumulated amortization	-86	-69
Total	$114	$131

ACCRUED_EXPENSES_Details

ACCRUED EXPENSES (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
ACCRUED EXPENSES
Accrued bonus		$566
Accrued payroll	49	101
Deferred rent payable	505	553
Accrued vacation	72	23
Accrued legal	360
Other accrued expenses	58	49
Total accrued expenses	$1,044	$1,292

NOTE_PAYABLE_Details

NOTE PAYABLE (Details) (USD $)	1 Months Ended
In Thousands, unless otherwise specified	31-May-13	Dec. 31, 2014	Dec. 31, 2013
Future minimum principal payments
2014		$18	$74
Note Payable
Note payable
Cost of purchase of ERP system	150
Total cost for ERP system including interest	159
Implicit interest rate	6.00%
Future minimum principal payments
2015		18
Total		$18

FAIR_VALUES_OF_ASSETS_AND_LIAB2

FAIR VALUES OF ASSETS AND LIABILITIES (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Assets and liabilities measured at fair value on a recurring basis
Derivative warrant liability	$7,224	$0	$14,585	$35,473
Recurring basis
Assets and liabilities measured at fair value on a recurring basis
Derivative warrant liability	7,224
Assets measured at fair value		0
Liabilities measured at fair value		0
Recurring basis | Level 2
Assets and liabilities measured at fair value on a recurring basis
Derivative warrant liability	7,224
Nonrecurring basis
Assets and liabilities measured at fair value on a recurring basis
Assets measured at fair value	0	0
Liabilities measured at fair value	$0	$0

CAPITAL_LEASE_PAYABLE_Details

CAPITAL LEASE PAYABLE (Details) (USD $)	12 Months Ended			1 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 28, 2011
Capital lease obligation
Less: current portion		($3)
Capital lease information
Depreciation expense	752	740	367
Assets under capital lease
Capital lease obligation
Capital lease payable		3
Less: current portion		-3
Capital lease information
Value of equipment acquired under capital lease agreement				124
Down payment on capital lease agreement				31
Monthly installments				3
Capital lease payable period				36 months
Final payment due date				1-Jan-14
Interest expense recorded on the capital lease	0	1
Depreciation expense	25
Net book value of capital lease	$27	$52

LOAN_PAYABLE_Details

LOAN PAYABLE (Details) (USD $)	1 Months Ended		12 Months Ended			1 Months Ended
In Thousands, except Share data, unless otherwise specified	Oct. 31, 2012	Sep. 30, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2011
MassDev
Loans Payable
Line of credit maximum borrowing capacity	$2,000
Line of credit for working capital purpose	200
Fixed interest rate (as a percent)	6.50%
Period for charging 6.5% interest rate	30 months
Period for charging equal interest and principal payments	54 months
Maturity date	5-Oct-19
Principal amount outstanding			1,920
Amount of monthly principal payment			36
Commencement date of monthly installments			1-May-15
Future Principal payment due: 2015			320
Future Principal payment due : 2016			427
Future Principal payment due : 2017			426
Future Principal payment due : 2018			427
Future Principal payment due : 2019			320
Line of credit facility commitment fees		15
Interest expense			127	120
MassDev | Warrants
Loans Payable
Number of shares into which a warrant may be converted	36,145
Warrant period	7 years
Exercise price of warrant (in dollars per share)	1.66
Approximate fair value of warrant	32
Amortization period of deferred financing cost	7 years
Amortization of deferred financing costs			5	5	5
MassDev | Equipment Line of Credit
Loans Payable
Withdrawal for capital equipment				342
Loan with a bank
Loans Payable
Line of credit maximum borrowing capacity						1,000
Line of credit facility commitment fees						10
Amortization of deferred financing costs					6
Interest expense					16
Interest rate, maximum (as a percent)						6.75%
Loan repayable period						36 months
Repayment of loans payable	134
Loan with a bank | Prime Rate
Loans Payable
Debt instrument, spread on variable rate						3.50%
Loan with a bank | Warrants
Loans Payable
Number of shares into which a warrant may be converted						16,071
Warrant period						7 years
Exercise price of warrant (in dollars per share)						1.4
Approximate fair value of warrant						$10

LOAN_PAYABLE_Detail_2

LOAN PAYABLE (Detail 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Summary of loans payable
Equipment Loan	$1,920	$1,920
Less: current portion	320
Non current portion of equipment loan	$1,600	$1,920

INCOME_TAXES_Details

INCOME TAXES (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Income Taxes
Provision or benefit for federal or state income taxes	$0
Research and development
Income Taxes
Research and development tax credit carryforwards	867
Beginning of expiration research and development tax credit carryforwards	2021
Federal
Income Taxes
Net operating loss carryforwards	58,293
Expiration of Federal net operating loss carryforwards	2026
Massachusetts
Income Taxes
Net operating loss carryforwards	$50,568
Operating losses carry forward expiration year	2011

INCOME_TAXES_Details_2

INCOME TAXES (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Significant components of net deferred tax asset
Net operating loss carryforward	$22,490	$16,032
Research and development credit carryforward	801	625
Stock-based compensation	2,265	2,411
Depreciation and amortization	-124	-149
Accrued expenses	226	449
Charitable contributions	112	112
Subtotal	25,770	19,480
Valuation allowance	-25,770	-19,480
Increase in valuation allowance	6,290	7,738
Uncertain tax positions	$0	$0

INCOME_TAXES_Details_3

INCOME TAXES (Details 3)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income tax benefits computed using the federal statutory income tax rate
Statutory rate	-34.00%	-34.00%	34.00%
State taxes, net of benefit	-4.80%	-2.60%	-14.20%
Permanent differences:
Derivative losses	0.70%	17.10%	-127.40%
Other	2.60%	0.00%	-1.90%
R&D tax credit	-1.00%	-0.40%	7.00%
True up, past year	2.20%	0.00%	0.00%
Increase in valuation reserve	34.30%	19.90%	102.50%
Effective tax rate	0.00%	0.00%	0.00%

COMMON_STOCK_Details

COMMON STOCK (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Common stock, number of shares, par value and other disclosures
Common stock, authorized	200,000,000	200,000,000
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, issued	93,812,000	78,773,736
Common stock, outstanding	93,812,000	78,773,736

COMMON_STOCK_Details_2

COMMON STOCK (Details 2) (USD $)	12 Months Ended			1 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2014	Dec. 31, 2014	Dec. 31, 2011
Common stock disclosures
Proceeds from exercise of stock options (in dollars)	$212	$456	$111
Proceeds from warrant exercises	12	15,952	1,129
Fair value of issuance of common stock to 401(k) plan	173	192	92
Fair value of stock issued for services	477		25
Issuance of stock for services (in dollars)	477		25
Common Stock And Warrants | Underwritten Public Offering
Common stock disclosures
Net proceeds from issuance of common stock	14,600
Issuance of equity (in shares)	14,001,250
Common Stock
Common stock disclosures
Issuance of stock upon exercise of stock options (in shares)	531,598	588,884	755,020
Proceeds from exercise of stock options (in dollars)	212	456	111
Issuance of stock upon exercise of warrants (in shares)	39,900	12,224,846	1,779,716
Warrants to purchase through cashless exercise provisions (in shares)	62,620	627,036	1,865,670
Shares issued through cashless exercise provisions	27,610
Warrants to purchase through cash exercise provisions (in shares)	12,290	11,813,334	852,946
Proceeds from warrant exercises	12	15,952	1,129
Issuance of stock to 401(k) plan (in shares)	167,011	78,884	47,105
Fair value of issuance of common stock to 401(k) plan	173
Issuance of stock for services (in shares)	298,505		15,000
Issuance of stock for services (in dollars)			25	282
Issuance of stock (in shares)	14,001,250		9,523,810
Exercise price (in dollars per share)						2.1
Common Stock | Michael J. Astrue, Then-Interim Chief Executive Officer
Common stock disclosures
Issuance of stock for services (in shares)				108,848
Common Stock | Gregory D. Perry, Then-Interim Chief Financial Officer
Common stock disclosures
Issuance of stock for services (in shares)				22,374
Common Stock | Certain Employees
Common stock disclosures
Issuance of stock for services (in shares)					167,283
Fair value of stock issued for services					195
Common Stock | Underwritten Public Offering
Common stock disclosures
Issuance of stock (in shares)	7,000,625
Equity issuance (in price per unit)	$1.15
Common Stock | Initial Public offering
Common stock disclosures
Issuance of stock (in shares)			9,523,810
Gross proceeds from issuance of stock (in dollars)			20,000
Net proceeds from issuance of common stock			$18,155
Equity issuance (in price per unit)			$2.10
Warrants | Underwritten Public Offering
Common stock disclosures
Equity issuance (in price per unit)	$0.00
Exercise price (in dollars per share)	1.4375				1.4375
Exercise price of warrants as percentage of offering price of common stock	125.00%

COMMON_STOCK_Details_3

COMMON STOCK (Details 3)	Dec. 31, 2014
Summary of common stock reserves
Total Reserves	22,570,294
Warrants
Summary of common stock reserves
Total Reserves	10,208,849
Stock options
Summary of common stock reserves
Total Reserves	12,361,445

DERIVATIVE_INSTRUMENTS_Details

DERIVATIVE INSTRUMENTS (Details) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended	12 Months Ended			1 Months Ended
In Thousands, except Share data, unless otherwise specified	17-May-13	31-May-13	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	31-May-14	Dec. 31, 2011
Class of Warrant or Right
Fair value of derivative warrant liability reclassified to additional paid-in capital		$25,241	$476		$33,456	$3,409
Redemption of outstanding investor warrants to common stock		11,726,343
Derivative instruments, fair value				7,224	0	14,585		35,473
Non-cash charge - Modification of warrants	765				765
Warrant derivative loss				-376	-18,871	17,480
Common Stock | Underwritten Public Offering
Class of Warrant or Right
Warrants issued with anti-dilution protection provisions							7,000,625
New Warrants
Class of Warrant or Right
Fair value of derivative warrant liability reclassified to additional paid-in capital	$7,738
Extended term of warrant	2 years
Warrants issued	3,319,091
Merger Warrants
Class of Warrant or Right
Warrants to purchase shares of common stock tendered and exchange	255,000
Placement Agent Warrants
Class of Warrant or Right
Warrants to purchase shares of common stock tendered and exchange	3,064,091

DERIVATIVE_INSTRUMENTS_Details1

DERIVATIVE INSTRUMENTS (Details 2)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2012
Fair value of warrants
Risk-free interest rate (as a percent)	1.47%
Expected dividend yield (as a percent)	0.00%	0.00%
Contractual term	4 years 4 months 24 days
Expected volatility (as a percent)	119.00%	73.00%
Minimum
Fair value of warrants
Risk-free interest rate (as a percent)		0.32%
Contractual term		2 years 8 months 12 days
Maximum
Fair value of warrants
Risk-free interest rate (as a percent)		0.35%
Contractual term		2 years 10 months 24 days

DERIVATIVE_INSTRUMENTS_Details2

DERIVATIVE INSTRUMENTS (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in derivative warrant liability
Balance at beginning of year	$0	$14,585	$35,473
Issuance of warrants	6,848
Increase (decrease) in the fair value of the warrants	376	18,871	-17,480
Fair value of derivative warrant liability reclassified to additional paid in capital		-33,456	-3,408
Balance at end of year	$7,224	$0	$14,585

STOCK_OPTIONS_Details

STOCK OPTIONS (Details) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock option
Options available to purchase/Common Stock outstanding	10,445,662	8,055,522
Exercisable period	6 years 11 days	6 years 3 months	6 years 3 months
Vesting period	5 years 1 month 28 days
Stock Options
Stock option
Stock-based compensation expense, net of forfeitures	2,730	3,136	1,233
Expected term of options granted	10 years
Vesting period	48 months
2007 Plan
Stock option
Options available to purchase/Common Stock outstanding	1,692,309
Shares available for future grants	0
Exercisable period	10 years
2010 Plan
Stock option
Options available to purchase/Common Stock outstanding	8,753,353
Shares available for future grants	1,748,500
Shares authorized for issuance	11,000,000
Exercisable period	10 years

STOCK_OPTIONS_Details_2

STOCK OPTIONS (Details 2)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Assumptions used principally in determining the fair value of options granted
Expected dividend yield (as a percent)	0.00%	0.00%	0.00%
Expected term	6 years 11 days	6 years 3 months	6 years 3 months
Expected volatility (as a percent)	124.00%	102.00%	75.00%
Minimum
Assumptions used principally in determining the fair value of options granted
Risk-free interest rate (as a percent)	1.62%	0.77%	0.62%
Maximum
Assumptions used principally in determining the fair value of options granted
Risk-free interest rate (as a percent)	2.06%	2.52%	1.23%

STOCK_OPTIONS_Details_3

STOCK OPTIONS (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary of option activity
Outstanding at the beginning of year (in shares)	8,055,522
Outstanding at the beginning of year (in dollars per shares)	$1.55
Granted (in shares)	4,711,250
Granted (in dollars per shares)	$1.75
Forfeited (in shares)	-1,770,948
Forfeited (in dollars per shares)	$1.86
Exercised (in shares)	-550,162
Exercised (in dollars per shares)	$0.42
Outstanding at the end of year (in shares)	10,445,662	8,055,522
Outstanding at the end of year (in dollars per shares)	$1.65	$1.55
Outstanding at the end of the period	7 years 7 months 10 days
Outstanding at the end of the period	$2,569
Vested at the end of period (in shares)	3,960,662
Vested at the end of period (in dollars per share)	$1.28
Vested at the end of period	5 years 1 month 28 days
Vested at the end of period (in dollars)	1,986
Stock Option
Weighted average grant-date fair value of options granted	$1.54	$2.04	$1.28
Total fair value of options vested	2,329,000	1,985,000	1,186,000
Total unrecognized compensation expense, related to non-vested share-based compensation arrangements	$5,750,000
Period for unrecognized compensation expense is estimated to be recognized	2 years 10 months 28 days

WARRANTS_Details

WARRANTS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Warrants to purchase common stock issued and outstanding
Number of Warrants	10,208,849
Weighted average exercise price	$1.43
Weighted average life in years	3 years 9 months 22 days
Equity | Derivative with Exercise Price One
Warrants to purchase common stock issued and outstanding
Warrants Issued Year	2010
Number of Warrants	1,494,603
Warrant Exercise Price	1.4
Equity | Derivative with Exercise Price One | Maximum
Warrants to purchase common stock issued and outstanding
Expiration date	3-Dec-17
Equity | Derivative with Exercise Price One | Minimum
Warrants to purchase common stock issued and outstanding
Expiration date	26-Oct-17
Equity | Derivative with Exercise Price Two
Warrants to purchase common stock issued and outstanding
Warrants Issued Year	2010
Number of Warrants	1,318,268
Warrant Exercise Price	1
Equity | Derivative with Exercise Price Two | Maximum
Warrants to purchase common stock issued and outstanding
Expiration date	3-Dec-15
Equity | Derivative with Exercise Price Two | Minimum
Warrants to purchase common stock issued and outstanding
Expiration date	26-Sep-15
Equity | Derivative with Exercise Price Three
Warrants to purchase common stock issued and outstanding
Warrants Issued Year	2011
Number of Warrants	16,071
Warrant Exercise Price	1.4
Expiration date	17-Jun-18
Equity | Derivative with Exercise Price Four
Warrants to purchase common stock issued and outstanding
Warrants Issued Year	2011
Number of Warrants	343,137
Warrant Exercise Price	3.06
Expiration date	21-Dec-16
Equity | Derivative with Exercise Price Five
Warrants to purchase common stock issued and outstanding
Warrants Issued Year	2012
Number of Warrants	36,145
Warrant Exercise Price	1.66
Expiration date	5-Oct-19
Liability | Derivative With Exercise Price Six
Warrants to purchase common stock issued and outstanding
Warrants Issued Year	2014
Number of Warrants	7,000,625
Warrant Exercise Price	1.44
Expiration date	9-May-19

EMPLOYEE_BENEFIT_PLAN_Details

EMPLOYEE BENEFIT PLAN (Details) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee benefit plan disclosures
Eligibility criteria for participation in the Plan	21 years
Fair value of issuance of common stock to 401(k) plan	$173	$192	$92
Common Stock
Employee benefit plan disclosures
Issuance of stock to 401(k) plan (in shares)	167,011	78,884	47,105
Fair value of issuance of common stock to 401(k) plan	$173

INTELLECTUAL_PROPERTY_LICENSE_

INTELLECTUAL PROPERTY LICENSE (Details) (Boston Childrens Hospital Bch License [Member], USD $)	0 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2014	Dec. 31, 2011
Boston Childrens Hospital Bch License [Member]
Intellectual Property License
Useful life	15 years
Initial license fee paid	$75
Additional License Fee Paid for expansion	75
Accrued Milestone payment	50		50
Capitalized license fees and milestone payments		$200

COMMITMENTS_AND_CONTINGENCIES_1

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	12 Months Ended			0 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 30, 2011	Sep. 04, 2013
Commitments and contingencies
Leasehold improvements	$390	$249
Future minimum rent commitments
2015	1,243
2016	1,269
2017	1,295
2018	1,049
Total	4,856
Commitments and contingencies
Total rent expense	1,148	1,125	758
Amount of settlement agreement					286
Cambridge
Commitments and contingencies
Lease Space for Laboratory and office space				26,150
Term of commercial lease				6 years 3 months
Lease extension option				5 years
Deferred rent liability	505
Standby letter of credit in favor of a landlord
Commitments and contingencies
Standby letter of credit	$311

COMMITMENTS_AND_CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Details 2) (USD $)	1 Months Ended	0 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Dec. 06, 2013
		claim
InVivo Therapeutics Holdings Corp. v. Reynolds
Litigation
Value of damages sought worth of personal and/or exorbitant expenses	$500
Reynolds counterclaim against InVivo Therapeutics Holdings Corp.
Litigation
Number of breach of contract claims		2
Number of breach of covenant of good faith and fair-dealing claims		2

INSURANCE_CLAIM_Details

INSURANCE CLAIM (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
September 2014 Water Damage Business Interruption | Research and development expense
Insurance claim disclosures
Insurance settlement recorded	($621)
November 2012 Water Damage Business Interruption
Insurance claim disclosures
Insurance settlement recorded		($1,100)

SUBSEQUENT_EVENTS_Details

SUBSEQUENT EVENTS (Details) (Subsequent event, Registered Direct Offering, USD $)	1 Months Ended
In Thousands, except Share data, unless otherwise specified	Jan. 31, 2015
Subsequent event | Registered Direct Offering
Subsequent event disclosures
Issuance of stock (in shares)	8,000,000
Proceeds From Issuance Of Common Stock, Net Of Offering Expenses	$11,000