Athersys, Inc / New (ATHXQ) 10-Q 11 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	8-May-15
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	ATHX
Entity Registrant Name	ATHERSYS, INC / NEW
Entity Central Index Key	1368148
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		82,881,666

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$35,505	$26,127
Accounts and other receivables	2,837	694
Prepaid expenses and other	386	427
Total current assets	38,728	27,248
Equipment, net	1,263	1,270
Deferred tax assets	200	200
Total assets	40,191	28,718
Current liabilities:
Accounts payable	2,727	2,767
Accrued compensation and related benefits	546	1,060
Accrued clinical trial costs	69	126
Accrued expenses	597	664
Deferred revenue	10,027	75
Note payable	185
Total current liabilities	14,151	4,692
Note payable		183
Warrant liabilities	7,025	2,948
Stockholders' equity:
Preferred stock, at stated value; 10,000,000 shares authorized, and no shares issued and outstanding at March 31, 2015 and December 31, 2014
Common stock, $0.001 par value; 150,000,000 shares authorized, and 81,906,707 and 77,706,816 shares issued and outstanding at March 31, 2015 and December 31, 2014, respectively	82	78
Additional paid-in capital	317,935	307,337
Accumulated deficit	-299,002	-286,520
Total stockholders' equity	19,015	20,895
Total liabilities and stockholders' equity	$40,191	$28,718

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	81,906,707	77,706,816
Common stock, shares outstanding	81,906,707	77,706,816

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues
Contract revenue	$106	$44
Grant revenue	625	663
Total revenues	731	707
Costs and expenses
Research and development	5,668	6,226
General and administrative	1,886	1,781
Depreciation	70	89
Total costs and expenses	7,624	8,096
Loss from operations	-6,893	-7,389
Other income, net	15	29
Expense from change in fair value of warrants, net	-5,604	-4,124
Net loss and comprehensive loss	($12,482)	($11,484)
Basic and diluted net loss per common share	($0.16)	($0.15)
Weighted average shares outstanding, basic and diluted	79,180,697	75,852,753

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Operating activities
Net loss	($12,482)	($11,484)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation	70	89
Stock-based compensation	751	579
Change in fair value of warrant liabilities and other	5,605	4,124
Changes in operating assets and liabilities:
Accounts receivable	-2,143	-374
Prepaid expenses and other	41	68
Accounts payable and accrued expenses	-678	-239
Deferred revenue	9,952	-40
Net cash provided by (used in) operating activities	1,116	-7,277
Investing activities
Purchases of equipment	-63	-150
Net cash used in investing activities	-63	-150
Financing activities
Proceeds from issuance of common stock and warrants, net	7,606	19,814
Purchase of treasury stock	-257	-292
Proceeds from exercise of warrants	976	938
Net cash provided by financing activities	8,325	20,460
Increase in cash and cash equivalents	9,378	13,033
Cash and cash equivalents at beginning of the period	26,127	31,948
Cash and cash equivalents at end of the period	$35,505	$44,981

Background_and_Basis_of_Presen

Background and Basis of Presentation	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Background and Basis of Presentation	1. Background and Basis of Presentation
	We are an international biotechnology company that is focused primarily in the field of regenerative medicine and operate in one business segment. Our operations consist primarily of research and product development activities.
	The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2014. The accompanying financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and Article 10 of Regulation S-X. Accordingly, since they are interim statements, the accompanying financial statements do not include all of the information and notes required by GAAP for complete financial statements. The accompanying financial statements reflect all adjustments, consisting of normal recurring adjustments, that are, in the opinion of management, necessary for a fair presentation of financial position and results of operations for the interim periods presented. Interim results are not necessarily indicative of results for a full year.
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Our critical accounting policies, estimates and assumptions are described in “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” which is included below in this Quarterly Report on Form 10-Q.

Recently_Issued_Accounting_Sta

Recently Issued Accounting Standards	3 Months Ended
	Mar. 31, 2015
Accounting Changes and Error Corrections [Abstract]
Recently Issued Accounting Standards	2. Recently Issued Accounting Standards
	In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606).” ASU 2014-09 requires an entity to recognize revenue in a manner that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, the amendment provides five steps that an entity should apply when recognizing revenue. The amendment also specifies the accounting of some costs to obtain or fulfill a contract with a customer and expands the disclosure requirements around contracts with customers. An entity can either adopt this amendment retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying the update recognized at the date of initial application. The amendment is effective for annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. In April 2015, the FASB issued an exposure draft of an ASU that would delay the effective date of ASU 2014-09 by one year. We are in the process of evaluating, but have not determined, the impact that the adoption of ASU 2014-09 will have on our consolidated financial statements.
	In August 2014, the FASB issued ASU 2014-15, “Presentation of Financial Statements - Going Concern, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern,” which establishes management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and, if so, to provide related footnote disclosures. ASU 2014-15 provides a definition of the term ‘substantial doubt’ and requires an assessment for a period of one year after the date that the financial statements are issued or available to be issued. Management will also be required to evaluate and disclose whether its plans alleviate that doubt. The guidance is effective for the annual periods ending after December 15, 2016 and interim periods thereafter with early adoption permitted. We are in the process of evaluating the impact the new guidance will have on our disclosures.

Net_Loss_per_Share

Net Loss per Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Net Loss per Share	3. Net Loss per Share
	Basic and diluted net loss per share have been computed using the weighted-average number of shares of common stock outstanding during the period. We have outstanding options, restricted stock units and warrants that are not used in the calculation of diluted net loss per share because to do so would be antidilutive. The following instruments were excluded from the calculation of diluted net loss per share because their effects would be antidilutive:
		Three months ended
		March 31,
		2015		2014
	Stock options		6,379,018		5,088,973
	Restricted stock units		1,635,755		2,224,096
	Warrants		8,364,893		9,480,103
	Total		16,379,666		16,793,172

Financial_Instruments

Financial Instruments	3 Months Ended
	Mar. 31, 2015
Investments, All Other Investments [Abstract]
Financial Instruments	4. Financial Instruments
	Fair Value Measurements
	We classify the inputs used to measure fair value into the following hierarchy:
	Level 1	Unadjusted quoted prices in active markets for identical assets or liabilities.
	Level 2	Unadjusted quoted prices in active markets for similar assets or liabilities, or unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or inputs other than quoted prices that are observable for the asset or liability.
	Level 3	Unobservable inputs for the asset or liability.
	The following table provides a summary of the financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 (in thousands):
					Fair Value Measurements at March 31, 2015 Using
	Description	Balance as of			Quoted Prices in Active		Significant Other		Significant Unobservable
		March 31, 2015			Markets for Identical		Observable Inputs		Inputs (Level 3)
					Assets (Level 1)		(Level 2)
	Warrant liabilities	$	7,025		$	—	$	—	$	7,025
	We review and reassess the fair value hierarchy classifications on a quarterly basis. Changes from one quarter to the next related to the observability of inputs in a fair value measurement may result in a reclassification between fair value hierarchy levels. There were no reclassifications for all periods presented.
	The estimated fair value of warrants accounted for as liabilities, representing a level 3 fair value measure, was determined on the issuance date and subsequently marked to market at each financial reporting date. We use the Black-Scholes valuation model to value the warrant liabilities at fair value. The fair value is estimated using the expected volatility based on our historical volatility for warrants issued after January 1, 2013, or for warrants issued prior to 2013, using the historical volatilities of comparable companies from a representative peer group selected based on industry and market capitalization. The fair value of the warrants is determined using probability weighted-average assumptions, when appropriate. The following inputs were used at March 31, 2015:
		Expected Volatility		Risk-Free Interest Rate	Expected Life
	Warrants with one year or less remaining term	61.71% - 61.95%		0.03% - 0.26%	0.17 - 0.84 year
	Warrants with greater than one year remaining term	68.95% - 90.69%		0.26% - 0.56%	1.29 - 1.96 years
	A roll-forward of fair value measurements using significant unobservable inputs (Level 3) for the warrants is as follows (in thousands):
		Three months
		ended
		March 31, 2015
	Balance January 1, 2015	$	2,948
	Settlements		(1,527	)
	Loss included in expense from change in fair value of warrants		5,604
	Balance March 31, 2015	$	7,025

Collaborations_and_Revenue_Rec

Collaborations and Revenue Recognition	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaborations and Revenue Recognition	5. Collaborations and Revenue Recognition
	Chugai
	In February 2015, we entered into an exclusive license agreement with Chugai Pharmaceutical Co., Ltd. (“Chugai”) to develop and commercialize MultiStem for the treatment of ischemic stroke in Japan. Chugai is responsible for development, regulatory activities and commercialization of MultiStem for ischemic stroke in Japan on an exclusive basis and will pay us for supplying a certain portion of its product requirements. The parties will share data and coordinate Japanese and global regulatory activities for treatment of ischemic stroke in Japan. Chugai will pay us royalties on net sales, starting in the low double digits and increasing incrementally to the high teens depending on net sales levels.
	We received a non-refundable, up-front cash payment of $10 million from Chugai, of which $2.0 million was temporarily withheld by Japan taxing authorities. The withholdings are refundable to us upon completion of tax filings under the United States and Japanese treaty, and the $2.0 million is recorded as a receivable at March 31, 2015. Under the terms of the agreement, Chugai will be required to pay us $7 million to continue the collaboration following its review of the interim results from our Phase 2 ischemic stroke study. In the event that Chugai does not make the $7 million payment, we can terminate the license agreement and all rights would revert to us, and we would retain the up-front $10 million payment. We delivered the interim results from our Phase 2 ischemic stroke study to Chugai in April 2015, and Chugai has several months to review the results before the payment is due.
	To determine the appropriate accounting for the license agreement, we have evaluated the agreement and related facts and circumstances, focusing in particular on the rights and obligations of the arrangement. We have determined that our obligations under the agreement represent multiple deliverables. In the period prior to Chugai’s decision to continue the collaboration and make the $7 million payment to us, the deliverables include the license grant and access to our technology, and importantly, the interim results of our stroke Phase 2 clinical study. For deliverables with standalone value, our policy is to account for these as separate units of accounting We allocate the overall consideration of the arrangement that is fixed and determinable, excluding consideration that is contingent upon future deliverables, to the separate units of accounting based on estimated selling prices (as defined in ASC 605-25) of each deliverable.
	We considered the deliverables at the inception of the arrangement and concluded that the license grant, for example, did not have standalone value (as defined in ASC 605-25) given that, at the time, the interim stroke Phase 2 clinical study results were not yet available to Chugai and use of the license would require the $7 million payment to us within several months after Chugai’s receipt of the study results. Accordingly, we have recorded the $10 million up-front payment as deferred revenue at March 31, 2015.
	Pfizer
	In 2009, we entered into a collaboration with Pfizer Inc. (“Pfizer”) to develop and commercialize our MultiStem product candidate to treat inflammatory bowel disease (“IBD”) for the worldwide market on an exclusive basis. Under the terms of the agreement, we received a $6 million non-refundable, up-front payment from Pfizer and research funding and support, totaling $6.25 million, through June 2012. In addition, Pfizer conducted a Phase 2 clinical study exploring the potential of MultiStem cell therapy to treat advanced and severe ulcerative colitis, and would be responsible for any subsequent development. Overall, the study results were disappointing, even though a single administration of the cell therapy may have had some short-term effects. Taking these results into account, following an internal portfolio review, Pfizer determined that it would not invest further in this program targeting IBD, as would be required by the collaboration, and in May 2015, notified us of this decision and its intent to terminate the license agreement effective in July 2015.
	In connection with the termination, all rights that Pfizer had to the program revert to us, and intellectual property generated through the collaboration will be owned by us. Pfizer will transfer to us all preclinical and clinical data relating to the program in its possession, all reports, records and other information relating to preclinical and clinical development, and ownership of all investigator brochures, regulatory filings and approvals related to the program. We will be free to use such information, data, filings and approvals for subsequent analyses and development in this area, and such research findings to support development in other areas, including immunology and inflammatory conditions.
	RTI Surgical, Inc.
	In 2010, we entered into an agreement with RTI Surgical, Inc. (“RTI”) to develop and commercialize biologic implants using our technology for certain orthopedic applications in the bone graft substitutes market on an exclusive basis. Under the terms of the agreement, we received a non-refundable license fee in installments and performed certain services that were concluded in 2012. We are eligible to receive cash payments upon the successful achievement of certain commercial milestones. We evaluated the nature of the events triggering these contingent payments and concluded that these events are substantive and that revenue will be recognized in the period in which each underlying triggering event occurs. No milestone revenue has been recognized to date. In addition, we began receiving in 2014 tiered royalties on worldwide commercial sales of implants using our technologies based on a royalty rate starting in the mid-single digits and increasing into the mid-teens. Any royalties may be subject to a reduction if third-party payments for intellectual property rights are necessary or commercially desirable to permit the manufacture or sale of the product.

Stockbased_Compensation

Stock-based Compensation	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation	6. Stock-based Compensation
	We have two incentive plans that authorized an aggregate of 11,500,000 shares of common stock for awards to employees, directors and consultants. These equity incentive plans authorize the issuance of equity-based compensation in the form of stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares and units, and other stock-based awards. As of March 31, 2015, a total of 1,882,368 shares of common stock have been issued under our equity incentive plans.
	As of March 31, 2015, a total of 1,602,859 shares were available for issuance under our equity compensation plans and stock-based awards to purchase 8,014,773 shares of common stock were outstanding. For the three-month periods ended March 31, 2015 and 2014, stock-based compensation expense was approximately $751,000 and $579,000, respectively. At March 31, 2015, total unrecognized estimated compensation cost related to unvested stock-based awards was approximately $4.8 million, which is expected to be recognized by the end of 2018 using the straight-line method.

Issuance_of_Common_Stock_and_W

Issuance of Common Stock and Warrants	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Issuance of Common Stock and Warrants	7. Issuance of Common Stock and Warrants
	In January 2014, we completed a registered direct offering generating net proceeds of approximately $18.8 million through the issuance of 5,000,000 shares of common stock and immediately exercisable warrants to purchase 1,500,000 shares of common stock with an exercise price of $4.50 per share that expire on July 15, 2016. The securities were sold in multiples of a fixed combination of one share of common stock and a warrant to purchase 0.30 shares of common stock at an offering price of $4.10 per fixed combination.
	In the first quarter of 2015, we sold 3,048,760 shares to Aspire Capital Fund, LLC (“Aspire Capital”) under our equity purchase agreement at an average price of $2.49 per share, generating aggregate proceeds of $7.6 million, and after March 31, 2015, we sold shares for approximately $2.8 million, in the aggregate, to Aspire Capital.
	As of March 31, 2015, we had the following outstanding warrants to purchase shares of common stock:
	Number of		Exercise Price		Expiration
	Underlying Shares
		1,310,000	$	3.55	2-Feb-16
		2,054,893	$	1.01	14-Mar-17
		3,500,000	$	2.75	31-May-15
		1,500,000	$	4.5	15-Jul-16
		8,364,893
	In January 2015, we amended the warrants we issued in December 2013 to purchase 3,500,000 shares of common stock to increase the exercise price from $2.50 to $2.75 per share and to extend the expiration date from March 31, 2015 to May 31, 2015.
	During the three months ended March 31, 2015, we received proceeds of approximately $976,000 from the exercise of warrants, resulting in the issuance of 966,184 shares of common stock in the aggregate.

Warrant_Liabilities

Warrant Liabilities	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Warrant Liabilities	8. Warrant Liabilities
	We account for common stock warrants as either liabilities or as equity instruments depending on the specific terms of the warrant agreement. Registered common stock warrants that could require cash settlement are accounted for as liabilities. We classify these warrant liabilities on the consolidated balance sheet as a non-current liability. The warrant liabilities are revalued at fair value at each balance sheet date subsequent to the initial issuance. Changes in the fair market value of the warrant are reflected in the consolidated statement of operations as income (expense) from change in fair value of warrants.
	The warrants we issued in the January 2014 and December 2013 registered direct offerings contain a provision for a cash payment in the event that the shares are not delivered to the holder within two trading days. The cash payment equals $10 per day per $2,000 of warrant shares for each day late. The warrants issued in the March 2012 private placement and the February 2011 registered direct offering each contain a provision for net cash settlement in the event that there is a fundamental transaction (e.g., merger, sale of substantially all assets, tender offer, or share exchange). If a fundamental transaction occurs in which the consideration issued consists of all cash or stock in a non-public company, then the warrant holder has the option to receive cash equal to a Black Scholes value of the remaining unexercised portion of the warrant. Further, the March 2012 warrants include price protection in the event we sell stock below the exercise price, as defined, and the exercise price as reduced in February 2013 to $1.01 per share as a result of the
	October 2012 public offering.
	The warrants have been classified as liabilities, as opposed to equity, due to the potential adjustment to the exercise price that could result upon late delivery of the shares or potential cash settlement upon the occurrence of certain events as described above, and are recorded at their fair values at each balance sheet date.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	9. Income Taxes
	We have U.S. federal, state and foreign net operating loss, research and development tax credit and foreign tax credit carryforwards that may be used to reduce future taxable income and tax liabilities. Substantially all of our deferred tax assets have been fully offset by a valuation allowance due to our cumulative losses. As a result of our October 2012 equity offering, the utilization of our net operating loss and tax credit carryforwards generated prior to October 2012 is substantially limited under Section 382 of the Internal Revenue Code. U.S. federal net operating loss carryforwards, research and development tax credits, and state and local net operating loss carryforwards generated after October 2012, as well as foreign net operating loss carryforwards and foreign tax credits, are not subject to annual limitations. In 2014, we recognized a refundable tax benefit related to research and development credits associated with our foreign subsidiary.

Recently_Issued_Accounting_Sta1

Recently Issued Accounting Standards (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Changes and Error Corrections [Abstract]
Revenue from Contracts with Customers	In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606).” ASU 2014-09 requires an entity to recognize revenue in a manner that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, the amendment provides five steps that an entity should apply when recognizing revenue. The amendment also specifies the accounting of some costs to obtain or fulfill a contract with a customer and expands the disclosure requirements around contracts with customers. An entity can either adopt this amendment retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying the update recognized at the date of initial application. The amendment is effective for annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. In April 2015, the FASB issued an exposure draft of an ASU that would delay the effective date of ASU 2014-09 by one year. We are in the process of evaluating, but have not determined, the impact that the adoption of ASU 2014-09 will have on our consolidated financial statements.
Presentation of Financial Statements	In August 2014, the FASB issued ASU 2014-15, “Presentation of Financial Statements - Going Concern, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern,” which establishes management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and, if so, to provide related footnote disclosures. ASU 2014-15 provides a definition of the term ‘substantial doubt’ and requires an assessment for a period of one year after the date that the financial statements are issued or available to be issued. Management will also be required to evaluate and disclose whether its plans alleviate that doubt. The guidance is effective for the annual periods ending after December 15, 2016 and interim periods thereafter with early adoption permitted. We are in the process of evaluating the impact the new guidance will have on our disclosures.

Net_Loss_per_Share_Tables

Net Loss per Share (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Instruments Excluded from Calculation of Diluted Net Loss Per Share	The following instruments were excluded from the calculation of diluted net loss per share because their effects would be antidilutive:
		Three months ended
		March 31,
		2015		2014
	Stock options		6,379,018		5,088,973
	Restricted stock units		1,635,755		2,224,096
	Warrants		8,364,893		9,480,103
	Total		16,379,666		16,793,172

Financial_Instruments_Tables

Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
Investments, All Other Investments [Abstract]
Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	The following table provides a summary of the financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 (in thousands):
					Fair Value Measurements at March 31, 2015 Using
	Description	Balance as of			Quoted Prices in Active		Significant Other		Significant Unobservable
		March 31, 2015			Markets for Identical		Observable Inputs		Inputs (Level 3)
					Assets (Level 1)		(Level 2)
	Warrant liabilities	$	7,025		$	—	$	—	$	7,025
Fair Value of Warrants Based on Historical Volatilities	The fair value of the warrants is determined using probability weighted-average assumptions, when appropriate. The following inputs were used at March 31, 2015:
		Expected Volatility		Risk-Free Interest Rate	Expected Life
	Warrants with one year or less remaining term	61.71% - 61.95%		0.03% - 0.26%	0.17 - 0.84 year
	Warrants with greater than one year remaining term	68.95% - 90.69%		0.26% - 0.56%	1.29 - 1.96 years
Roll-Forward of Fair Value Measurements Using Significant Unobservable Inputs (Level 3) for Warrants	A roll-forward of fair value measurements using significant unobservable inputs (Level 3) for the warrants is as follows (in thousands):
		Three months
		ended
		March 31, 2015
	Balance January 1, 2015	$	2,948
	Settlements		(1,527	)
	Loss included in expense from change in fair value of warrants		5,604
	Balance March 31, 2015	$	7,025

Issuance_of_Common_Stock_and_W1

Issuance of Common Stock and Warrants (Tables)	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Outstanding Warrants to Purchase Shares of Common Stock	As of March 31, 2015, we had the following outstanding warrants to purchase shares of common stock:
	Number of		Exercise Price		Expiration
	Underlying Shares
		1,310,000	$	3.55	2-Feb-16
		2,054,893	$	1.01	14-Mar-17
		3,500,000	$	2.75	31-May-15
		1,500,000	$	4.5	15-Jul-16
		8,364,893

Background_and_Basis_of_Presen1

Background and Basis of Presentation - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2015
	Segment
Accounting Policies [Abstract]
Number of business segments	1

Net_Loss_per_Share_Instruments

Net Loss per Share - Instruments Excluded from Calculation of Diluted Net Loss Per Share (Detail)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	16,379,666	16,793,172
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	6,379,018	5,088,973
Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	1,635,755	2,224,096
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	8,364,893	9,480,103

Financial_Instruments_Summary_

Financial Instruments - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrant liabilities	$7,025	$2,948
Fair Value Measurements, Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrant liabilities	7,025
Fair Value Measurements, Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrant liabilities	$7,025

Financial_Instruments_Fair_Val

Financial Instruments - Fair Value of Warrants Based on Historical Volatilities (Detail)	3 Months Ended
	Mar. 31, 2015
Warrants With Greater Than One Year Remaining Term [Member] | Minimum [Member]
Class of Warrant or Right [Line Items]
Expected volatility	68.95%
Risk-Free Interest Rate	0.26%
Expected Life	1 year 3 months 15 days
Warrants With Greater Than One Year Remaining Term [Member] | Maximum [Member]
Class of Warrant or Right [Line Items]
Expected volatility	90.69%
Risk-Free Interest Rate	0.56%
Expected Life	1 year 11 months 16 days
Warrants With One Year or Less Remaining Term [Member] | Minimum [Member]
Class of Warrant or Right [Line Items]
Expected volatility	61.71%
Risk-Free Interest Rate	0.03%
Expected Life	2 months 1 day
Warrants With One Year or Less Remaining Term [Member] | Maximum [Member]
Class of Warrant or Right [Line Items]
Expected volatility	61.95%
Risk-Free Interest Rate	0.26%
Expected Life	10 months 2 days

Financial_Instruments_RollForw

Financial Instruments - Roll-Forward of Fair Value Measurements Using Significant Unobservable Inputs (Level 3) for Warrants (Detail) (Outstanding Warrants [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015
Outstanding Warrants [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Beginning Balance	$2,948
Settlements	-1,527
Loss included in expense from change in fair value of warrants	5,604
Ending Balance	$7,025

Collaborations_and_Revenue_Rec1

Collaborations and Revenue Recognition - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015
Pfizer [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Up-front cash payment received	$6,000,000
Deferred revenue recognized totaling	6,250,000
RTI Surgical Inc [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Commercial milestone revenue	0
Chugai Collaboration [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Up-front cash payment received	10,000,000
Deferred revenue withheld	2,000,000
Deferred revenue recorded as receivable	2,000,000
Potential near-term payment received	7,000,000
Deferred revenue outstanding payment	7,000,000
Revenue retained in up-front	$10,000,000

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
	Plans
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of incentive plans	2
Common stock authorized for equity incentive plans	11,500,000
Common stock shares issued	1,882,368
Shares available for issuance	1,602,859
Shares of common stock outstanding	8,014,773
Stock-based compensation expense	$751,000	$579,000
Total unrecognized estimated compensation cost	$4,800,000

Issuance_of_Common_Stock_and_W2

Issuance of Common Stock and Warrants - Additional Information (Detail) (USD $)	1 Months Ended			3 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Dec. 31, 2013	Mar. 31, 2015	Mar. 31, 2014	Feb. 28, 2013
Class of Warrant or Right [Line Items]
Proceeds from issuance of common stock, net		$18,800,000
Issuance of common stock, new issues		5,000,000
Warrants issued to purchase common stock	3,500,000	1,500,000	3,500,000
Warrant exercise price per share		$4.50				$1.01
Warrants exercise expiration date	31-May-15	15-Jul-16	31-Mar-15
Common stock per warrant conversion ratio		0.3
Common stock and warrant combined offering price		$4.10
Proceeds from exercise of warrants				976,000	938,000
Issuance of common stock from warrant exercises				966,184
Aspire [Member] | Common Stock [Member]
Class of Warrant or Right [Line Items]
Issuance of common stock, new issues				3,048,760
Sale of shares at an average price				$2.49
Issuance of common stock, new issues				7,600,000
Issuance of common stock and warrants, new issues value				$2,800,000
Minimum [Member]
Class of Warrant or Right [Line Items]
Warrant exercise price per share			2.5
Maximum [Member]
Class of Warrant or Right [Line Items]
Warrant exercise price per share	2.75

Issuance_of_Common_Stock_and_W3

Issuance of Common Stock and Warrants - Outstanding Warrants to Purchase Shares of Common Stock (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Jan. 31, 2014	Feb. 28, 2013
Class of Warrant or Right [Line Items]
Number of Underlying Shares	8,364,893
Exercise Price		$4.50	$1.01
February 2, 2016 [Member]
Class of Warrant or Right [Line Items]
Number of Underlying Shares	1,310,000
Exercise Price	$3.55
Expiration	2-Feb-16
March 14, 2017 [Member]
Class of Warrant or Right [Line Items]
Number of Underlying Shares	2,054,893
Exercise Price	$1.01
Expiration	14-Mar-17
May 31, 2015 [Member]
Class of Warrant or Right [Line Items]
Number of Underlying Shares	3,500,000
Exercise Price	$2.75
Expiration	31-May-15
July 15, 2016 [Member]
Class of Warrant or Right [Line Items]
Number of Underlying Shares	1,500,000
Exercise Price	$4.50
Expiration	15-Jul-16

Warrant_Liabilities_Additional

Warrant Liabilities - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Jan. 31, 2014	Feb. 28, 2013
Equity [Abstract]
Terms of issuance of warrant demanding cash payments	The warrants we issued in the January 2014 and December 2013 registered direct offerings contain a provision for a cash payment in the event that the shares are not delivered to the holder within two trading days. The cash payment equals $10 per day per $2,000 of warrant shares for each day late.
Number of trading days to deliver shares under warrants provision	2 days
Value of warrants considered for cash payment for late delivery of shares	$2,000
Cash payment per day for warrants shares not delivered as per provision	$10
Warrant exercise price per share		$4.50	$1.01