Harvard Apparatus Regenerative Technology (HRGN) 10-Q 15 Dec 17 2017 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Dec. 13, 2017
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Entity Registrant Name	Biostage, Inc.
Entity Central Index Key	1,563,665
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company
Trading Symbol	BSTG
Entity Common Stock, Shares Outstanding		39,787,615

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Cash	$ 1,310	$ 2,941
Accounts receivable	0	42
Prepaid expenses	94	291
Other current assets	274	212
Total current assets	1,678	3,486
Property, plant and equipment, net	875	1,065
Total assets	2,553	4,551
Current liabilities:
Accounts payable	1,208	962
Accrued and other current liabilities	529	1,210
Warrant liabilities	339	605
Total current liabilities	2,076	2,777
Total liabilities	2,076	2,777
Stockholders’ equity:
Preferred stock	0	0
Common stock, $0.01 par value; 120,000,000 shares and 60,000,000 shares authorized as of September 30, 2017 and December 31, 2016, respectively, and 39,787,615 and 17,108,968 shares issued and outstanding as of September 30, 2017 and December 31, 2016, respectively	398	171
Additional paid-in capital	47,084	37,921
Accumulated deficit	(47,005)	(36,318)
Total stockholders’ equity	477	1,774
Total liabilities and stockholders’ equity	2,553	4,551
Series B Convertible Preferred Stock [Member]
Stockholders’ equity:
Preferred stock	$ 0	$ 0

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	120,000,000	60,000,000
Common stock, shares issued	39,787,615	17,108,968
Common stock, shares outstanding	39,787,615	17,108,968
Undesignated Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Series B Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	695,857	695,857
Preferred stock, shares outstanding	0	0

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues	$ 0	$ 26	$ 0	$ 54
Cost of revenues	0	13	0	57
Gross profit (deficit)	0	13	0	(3)
Operating expenses:
Research and development	2,364	2,225	7,121	5,279
Selling, general and administrative	888	937	2,906	3,261
Total operating expenses	3,252	3,162	10,027	8,540
Operating loss	(3,252)	(3,149)	(10,027)	(8,543)
Other income (expense):
Change in fair value of liability warrants	9	96	(660)	306
Other expense	0	0	0	0
Other expense, net	9	96	(660)	306
Loss before income taxes	(3,243)	(3,053)	(10,687)	(8,237)
Income taxes	0	0	0	0
Net loss	$ (3,243)	$ (3,053)	$ (10,687)	$ (8,237)
Basic and diluted net loss per share (in dollars per share)	$ (0.08)	$ (0.18)	$ (0.31)	$ (0.53)
Weighted average common shares, basic and diluted (in shares)	38,969	17,107	34,443	15,585
Comprehensive loss:
Net loss	$ (3,243)	$ (3,053)	$ (10,687)	$ (8,237)
Foreign currency translation adjustments	0	0	0	0
Total comprehensive loss	$ (3,243)	$ (3,053)	$ (10,687)	$ (8,237)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities
Net loss	$ (10,687)	$ (8,237)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation expense	591	1,027
Depreciation	334	340
Change in fair value of warrant liability	660	(306)
Changes in operating assets and liabilities:
Accounts receivable	42	(45)
Inventories	0	34
Prepaid expenses and other current assets	135	234
Accounts payable	246	418
Accrued and other current liabilities	(681)	465
Net cash used in operating activities	(9,360)	(6,070)
Cash flows from investing activities
Additions to property and equipment	(140)	(225)
Net cash used in investing activities	(140)	(225)
Cash flows from financing activities
Proceeds from issuance of common stock and warrants, net of issuance costs	6,801	4,496
Proceeds from exercise of warrants	1,059	0
Proceeds from issuance of common stock, net of issuance costs	9	349
Net cash provided by financing activities	7,869	4,845
Net decrease in cash	(1,631)	(1,450)
Cash at beginning of period	2,941	7,456
Cash at end of period	1,310	6,006
Supplemental disclosure of cash flow information and non-cash investing and financing activities:
Fair value of warrant liability reclassified to additional paid-in capital	4,327	0
Fair value of warrants issued in connection with issuance of common stock	3,787	0
Equipment purchases included in accounts payable	0	28
Fair value of warrants issued to placement agent	$ 0	$ 116

Overview and Basis of Presentat

Overview and Basis of Presentation	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Business Description and Basis of Presentation [Text Block]	1. Overview Biostage, Inc. (“Biostage” or the “Company”) is a biotechnology company developing bioengineered organ implants based on our novel Cellframe TM . Since inception, the Company has devoted substantially all of its efforts to business planning, research and development, recruiting management and technical staff, and acquiring operating assets. Basis of Presentation The financial statements reflect the Company’s financial position, results of operations and cash flows in conformity with accounting principles generally accepted in the United States (“GAAP”). Net loss per Share Basic net loss per share is computed using the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed using the sum of the weighted average number of common shares outstanding during the period and, if dilutive, the weighted average number of potential shares of common stock, including the assumed exercise of stock options, warrants, and the impact of unvested restricted stock. The Company applies the two-class method to calculate basic and diluted net loss per share attributable to common stockholders as its warrants to purchase common stock are participating securities. The two-class method is an earnings allocation formula that treats a participating security as having rights to earnings that otherwise would have been available to common stockholders. However, the two-class method does not impact the net loss per share of common stock as the Company has been in a net loss position and the warrant holders do not participate in losses. Basic and diluted shares outstanding are the same for each period presented as all common stock equivalents would be antidilutive due to the net losses incurred. Unaudited Interim Financial Information The accompanying interim consolidated balance sheet as of September 30, 2017 and consolidated interim statements of operations and comprehensive loss and cash flows for the three and nine months ended September 30, 2017 and 2016 are unaudited. The interim unaudited consolidated financial statements have been prepared in accordance with GAAP on the same basis as the annual audited financial statements and, in the opinion of management, reflect all adjustments necessary for a fair statement of the Company’s financial position as of September 30, 2017 and its results of operations and cash flows for the three and nine month periods ended September 30, 2017 and 2016. The financial data and other information disclosed in these notes related to the three and nine month periods ended September 30, 2017 and 2016 are unaudited. The results for the three and nine months ended September 30, 2017 are not necessarily indicative of results to be expected for the year ending December 31, 2017, any other interim periods or any future year or period.

Summary of Significant Accounti

Summary of Significant Accounting Policies and Recently Issued Accounting Pronouncements	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	2. Summary of Significant Accounting Policies The accounting policies underlying the accompanying unaudited consolidated financial statements are those set forth in Note 2 to the financial statements for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K.

Capital Stock, Financing and Li

Capital Stock, Financing and Liquidity	9 Months Ended
	Sep. 30, 2017
Stockholders Equity Note [Abstract]
Stockholders Equity Note Disclosure [Text Block]	3. Capital Stock On February 10, 2017, the Company completed a public offering of 20,000,000 shares of common stock at a purchase price of $0.40 per share and the issuance of warrants to purchase 20,000,000 shares of common stock at an exercise price of $0.40 per warrant for gross proceeds of $8.0 million or approximately $6.8 million net of issuance costs. Additionally, the Company issued to the placement agent warrants to purchase 1,000,000 shares of common stock for the offering at an exercise price of $0.50 per warrant. The warrants are immediately exercisable and remain exercisable for five years from date of grant. During the three and nine months ended September 31, 2017 holders exercised warrants for 2,647,338 shares of common stock for proceeds of $1.1 million. On May 19, 2016, the Company closed on a Securities Purchase Agreement for the sale by the Company of 2,836,880 shares of the Company’s common stock at a purchase price of $1.7625 per share and the issuance of warrants to purchase 1,418,440 shares of common stock at an exercise price of $1.7625 per warrant for gross proceeds of $5.0 million or $4.6 million, net of issuance costs. Additionally, the Company issued warrants to purchase 141,844 shares of common stock to the placement agent for the offering at an exercise price of $1.7625 per warrant. The warrants are initially exercisable commencing November 19, 2016 through their expiration date of May 19, 2021. On December 15, 2015, the Company entered into a common stock purchase agreement (the “Aspire Capital Purchase Agreement”) with Aspire Capital Fund, LLC, (“Aspire Capital”), under which Aspire Capital was committed to purchase up to an aggregate of $15.0 million of the Company’s common stock over the approximately thirty month term of the Aspire Capital Purchase Agreement. In consideration for entering into the Aspire Capital Purchase Agreement, concurrently with the execution of the Aspire Capital Purchase Agreement, the Company issued Aspire Capital 150,000 shares of common stock as a commitment fee. Upon execution of the Aspire Capital Purchase Agreement, the Company sold to Aspire Capital 500,000 shares of common stock at $2.00 per share, which resulted in net proceeds of approximately $0.9 million. On May 12, 2016, the Company issued 150,000 shares of common stock under the Aspire Capital Purchase Agreement in exchange for gross proceeds of $0.37 million, or $0.35 million net of issuance costs. On May 17, 2016, the Company terminated the Aspire Capital Purchase Agreement without any penalty or cost. Capital Commitment On June 26, 2017, the Company entered into a binding Memorandum of Understanding (the “Pecos MOU”) with First Pecos, LLC (“First Pecos”), pursuant to which the Company agreed to issue to First Pecos in a private placement (the “P ecos Placement”) 9,700,000 shares of its common stock at a purchase price of $0.315 per share or, to the extent First Pecos, following the transaction, would own more than 19.9% of the Company’s common stock, shares of a new class of preferred stock of the Company (the “Preferred Stock”) with a per-share purchase price of $1,000. Additionally, First Pecos was to have d have been ecos Under the P ecos In connection with the P ecos ecos The Pecos Placement was conditioned on satisfaction of customary closing conditions, including the Company terminating its Shareholder Rights Plan, and was expected to be consummated on or prior to August 15, 2017. The definitive agreements relating to the Pecos Placement were to include customary representations, warranties and covenants. The Company agreed to file a resale registration statement promptly after the closing of the Pecos Placement to register the resale of the shares of common stock issued in the Pecos Placement. The Pecos MOU was intended to be binding upon both the Company and First Pecos. In the event that the Company failed to perform any of its obligations under the Pecos MOU or otherwise breached the Pecos MOU, subject to certain exceptions, First Pecos could terminate the Pecos MOU, and the Company would have been obligated to pay a termination fee of $ million (the “ . The Company entered into the Securities Purchase Agreement (the “Purchase Agreement) with First Pecos on August 11, 2017, pursuant to which the Company agreed to sell to First Pecos, and First Pecos agreed to purchase from the Company, shares of the Company’s common stock at a purchase price of $ per share or, to the extent First Pecos, following the transaction, would own more than % of the Company’s common stock, shares of a new class of preferred stock of the Company with a per-share purchase price of $ . Additionally, First Pecos w as to receive a warrant to purchase shares of the Company’s common stock (or, to the extent First Pecos would own more than 19.99% of the Company’s common stock, shares of Preferred Stock). The aggregate gross proceeds from the private placement of common stock, Preferred Stock and the Warrant would have be en $ (the “Purchase Price”). The Company did not receive the Purchase Price from First Pecos . On October 5, 2017, the Company delivered a notice (the “Notice”) to First Pecos and its manager, Leon “Chip” Greenblatt III, stating that First Pecos was in breach of the Purchase Agreement as a result of its failure to deliver the Purchase Price to the Company following satisfaction of all closing conditions in the Purchase Agreement. None of the shares of common stock, shares of Preferred Stock or Warrants were On October 10, 2017, First Pecos delivered a notice to the Company stating that, as a result of alleged breaches by the Company of its obligations pursuant to the Purchase Agreement, First Pecos terminated the Purchase Agreement and demanded that the Company pay the T F The Company believes that it was not in breach of the Purchase Agreement at any time, and that First Pecos’s notice was unjustified and without any legal merit or factual basis. Accordingly, the Company believes that First Pecos was not entitled to terminate the Purchase Agreement, and is not entitled to the Termination Fee, as the failure to consummate the Pecos Placement resulted from First Pecos’s breach of the Purchase Agreement. The Company is reviewing all of its rights and remedies against First Pecos that may be available to the Company. NASDAQ Compliance and OTCQB Exchange Quotation The Company had been operating under a grace period from November 18, 2016 through May 17, 2017 with respect to non-compliance of the listing requirements on N ASDAQ A SDAQ A SDAQ A SDAQ The Company determined that as a result of the termination of the Purchase Agreement it could not regain compliance with The NASDAQ Capital Market listing standards by the deadline imposed by NASDAQ, and on October 4, 2017 the Company withdrew its appeal from the Panel. On October 4, 2017, following the withdrawal by the Company of its appeal to the Panel, the Company received written notification from NASDAQ indicating that the Panel had determined to delist the Company’s common stock from The NASDAQ Capital Market, and suspended it from trading on that marketplace effective with the open of business on October 6, 2017. NASDAQ also informed the Company that it would file a Form 25-NSE with the Securities and Exchange Commission (the “SEC”) to remove the Company’s common stock from listing on NASDAQ , which was filed with the SEC on December 7, 2017 . . The Company’s common stock began trading on the OTCQB marketplace at the open of business on October 6, 2017. The Company’s common stock continues to trade under the symbol “BSTG”. The delisting of the Company’s common stock from The NASDAQ Capital Market may adversely affect the Company’s ability to raise the significant additional capital that it will require, through public or private sales of equity securities, which may in turn adversely affect the ability of investors to trade the Company’s securities and may negatively impact the value and liquidity of the Company’s common stock. The delisting could also cause the Company to face significant adverse consequences affecting trading in its common stock, including, among others: · because are · reduced trading levels could result in limited or no analyst coverage for the Company; · potential limited availability of market quotations for the Company’s common stock could adversely affect liquidity; and · restrictions on the Company’s ability to issue additional securities (including pursuant to short-form registration statements on Form S-3) or obtain additional financing in the future. Warrants The Company has issued warrants to purchase common stock, and the warrant activity during the nine months ended September 30, 2017 was as follows: Warrants Amount Weighted-average Outstanding at December 31, 2016 1,560,284 $ 1.76 Granted 21,000,000 0.40 Exercised (2,647,338) 0.40 Outstanding at September 30, 2017 19,912,946 $ 0.49 Other On April 26, 2017, the Company’s stockholders approved the following proposals at the Company’s Annual Meeting of Shareholders: · An amendment of the Company’s 2013 Equity Incentive Plan to increase the number of shares of the Company’s common stock available for issuance pursuant to the 2013 Plan by 4,000,000 shares; and · An amendment of the Company’s charter to effect a reverse stock split of the shares of the Company’s common stock at a ratio of not less than 1-for-2 and not greater than 1-for-20, with the exact ratio of, effective time of and decision whether or not to implement a reverse stock split to be determined by the Company’s board of directors. There has been no decision by the Company’s board of directors as to whether to implement a reverse stock split as of September 30, 2017. Liquidity The Company has incurred substantial operating losses since its inception, and as of September 30, 2017 had an accumulated deficit of approximately $47.0 million. The Company is currently investing significant resources in development and commercialization of products for use by clinicians in the field of regenerative medicine. The Company expects to continue to incur operating losses and negative cash flows from operations for the remainder of 2017 and in future years. As a result of First Pecos's refusal to deliver the Purchase Price, the Company is facing significant capital issues, as its current financial obligations exceed its cash on hand, and is exploring financing and other strategic alternatives. The Company cannot provide any assurance that it will be able to obtain sufficient financing. Therefore, these conditions raise substantial doubt about the Company’s ability to continue as a going concern. The Company will need to raise additional funds in future periods to fund its operations. In the event that the Company does not raise additional capital from outside sources in the near future, it may be forced to further curtail or cease its operations. Cash requirements and cash resource needs will vary significantly depending upon the timing and the financial and other resource needs that will be required to complete ongoing development and pre-clinical and clinical testing of products as well as regulatory efforts and collaborative arrangements necessary for the Company’s products that are currently under development. The Company will seek to raise necessary funds through a combination of public or private equity offerings, debt financings, other financing mechanisms, or strategic collaborations and licensing arrangements. The Company may not be able to obtain additional financing on terms favorable to it, if at all. The Company’s operations will be adversely affected if it is unable to raise or obtain needed funding, which materially affects our ability to continue as a going concern. The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern and therefore, the financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amount and classifications of liabilities that may result from the outcome of this uncertainty.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Disclosures [Text Block]	4. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. On May 19, 2016 and February 10, 2017, the Company closed on the sale of shares of the Company’s common stock, the issuance of warrants to purchase shares of common stock, and the issuance of warrants to the placement agent for each transaction. Due to a cash put provision within the warrant agreement, which could be enacted in certain change in control events, a liability associated with those warrants was initially recorded at fair value in the Company’s consolidated balance sheets upon issuance, and subsequently re-measured each fiscal quarter. The changes in the fair value between issuance and the end of each reporting period is recorded as a component of other income (expense), net in the consolidated statement of operations and comprehensive loss. During the three and nine months ended September 30, 2017, warrant holders of 19,043,696 warrants agreed to the modification of the terms of their warrants, which resulted in placing all situations that would allow the warrant holder to put the warrant for cash fully in control of the Company. As a result of the modification, the warrants are no longer liability classified and do not need to be re-measured. These modifications resulted in the $4.3 million fair value of those warrants being reclassified from Warrant Liabilities to Additional Paid in Capital. The remaining un-modified The Company utilizes a valuation hierarchy for disclosure of the inputs to the valuations used to measure fair value. This hierarchy prioritizes the inputs into three broad levels as follows. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the asset or liability, either directly or indirectly through market corroboration, for substantially the full term of the financial instrument. Level 3 inputs are unobservable inputs based on the Company’s own assumptions used to measure assets and liabilities at fair value. A financial asset or liability’s classification within the hierarchy is determined based on the lowest level input that is significant to the fair value measurement. The Company had no assets or liabilities classified as Level 1 or Level 2. The Company has concluded that its warrants meet the definition of a liability under ASC 480 Distinguishing Liabilities From Equity The Company has re-measured the liability to estimated fair value at inception, prior to modification and at each reporting date using the Black-Scholes option pricing model with the following weighted average assumptions: Assumptions for estimating fair value of warrants Assumptions for estimating fair value on reporting September 30, 2017 June 30, 2017 September 30, 2017 December 31, 2016 Risk-free interest rate 1.89 % 1.77 % 1.93 % 1.93 % Expected volatility 82.3 % 82.4 % 85.0 % 72.7 % Expected term (in years) 4.6 4.6 4.4 4.9 Expected dividend yield - - - - Exercise price $ 0.40 $ 0.50 $ 0.40 $ 1.76 Market value of common stock $ 0.41 $ 0.33 $ 0.31 $ 0.89 Warrants to purchase shares of common stock 2,002,037 16,568,846 1,844,250 1,560,284 The following fair value hierarchy table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of September 30, 2017: Fair Value Measurement as of September 30, 2017 (In thousands) Level 1 Level 2 Level 3 Total Warrant liability $ - $ - $ 339 $ 339 Total $ - $ - $ 339 $ 339 The following fair value hierarchy table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2016: Fair Value Measurement as of December 31, 2016 (In thousands) Level 1 Level 2 Level 3 Total Warrant liability $ - $ - $ 605 $ 605 Total $ - $ - $ 605 $ 605 The following table presents a reconciliation of the Company’s liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the nine months ended September 30, 2017: Warrant Liability (in thousands) Balance at December 31, 2016 $ 605 Issuance of warrants 3,787 Change in fair value upon re-measurement 274 Reclassification of warrant liability to additional paid in capital upon modification (3,746) Reclassification of warrant liability to additional paid in capital upon exercise (581) Balance at September 30, 2017 $ 339 Issuance costs allocated to the warranty liability issued in the first quarter of 2017 amounted to $385,000 and have been included in the change in fair value of the warranty liability in the accompanying consolidated statements of operations. There were no transfers between Level 1 and Level 2 in any of the periods reported.

Relationship with Harvard Biosc

Relationship with Harvard Bioscience	9 Months Ended
	Sep. 30, 2017
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	5. On October 31, 2013, Harvard Bioscience, Inc. (“Harvard Bioscience”) contributed its regenerative medicine business assets, plus $15 million of cash, into Biostage (the “Separation”). On November 1, 2013, the spin-off of the Company from Harvard Bioscience was completed. On that date, the Company became an independent company that operates the regenerative medicine business previously owned by Harvard Bioscience. The spin-off was completed through the distribution of all the shares of common stock of Biostage to Harvard Bioscience stockholders (the “Distribution”). At the time of the Separation, the Company entered into a 10-year product distribution agreement with Harvard Bioscience under which each company will become the exclusive distributor for the other party for products such other party develops for sale in the markets served by the other. In addition, Harvard Bioscience has agreed that except for certain existing activities of its German subsidiary, to the extent that any Harvard Bioscience business desires to resell or distribute any bioreactor that is then manufactured by the Company, the Company will be the exclusive manufacturer of such bioreactors and Harvard Bioscience will purchase such bioreactors from the Company. Since inception of the Company, sales to Harvard Bioscience accounted for % of the Company’s revenues and receivables. From the time of the Company’s spin-off from Harvard Bioscience through 2016, the Company manufactured research bioreactors. That business represented a small portion of the Company’s operations. In late 2016 , t he The Company

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2017
Share-based Compensation [Abstract]
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]	6. Biostage 2013 Equity Incentive Plan The Company maintains the 2013 Equity Incentive Plan (the “Plan”) for the benefit of certain of its officers, employees, non-employee directors, and other key persons (including consultants and advisory board members). All options and awards granted under the Plan consist of the Company’s shares of common stock. The Company also issued equity awards under the Plan at the time of the Distribution to all holders of Harvard Bioscience equity awards as part of an adjustment (the “Adjustment”) to prevent a loss of value due to the Distribution. Compensation expense recognized under the Plan relates to service provided by employees, board members and a non-employee of the Company. There was no required compensation associated with the Adjustment awards to employees who remained at Harvard Bioscience. The Company has granted options to purchase common stock and restricted stock units (RSUs) under the Plan. Stock option and restricted stock unit activity during the nine months ended September 30, 2017 was as follows: Stock Options Restricted Stock Units Amount Weighted-average Amount Weighted -average Outstanding at December 31, 2016 3,877,681 $ 2.81 268 $ 6.00 Granted 1,896,500 0.40 404,750 0.38 Vested (RSUs) - - (268) 6.00 Canceled (569,865) 1.67 - - Outstanding at September 30, 2017 5,204,316 $ 2.05 404,750 $ 0.38 The Company uses the Black-Scholes option pricing model to value its stock options. The weighted average assumptions for valuing the options granted during the nine months ended September 30, 2017 were as follows: Expected volatility 78.71 % Expected dividends 0.00 % Expected term 6.26 years Risk-free rate 2.25 % The Company recorded equity-based compensation expense in the following expense categories of its consolidated statements of operations: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (in thousands) (in thousands) Research and development $ 98 $ 198 $ 281 $ 535 General and administrative 96 164 310 492 Total stock-based compensation $ 194 $ 362 $ 591 $ 1,027 Included in the above table for 2016 is stock-based compensation related to the Harvard Bioscience Plan, which is described below. There is no expense related to the Harvard Bioscience Plan in 2017. Harvard Bioscience Stock Option and Incentive Plan Harvard Bioscience maintains the Third Amended and Restated 2000 Stock Option and Incentive Plan (as amended, the “Harvard Bioscience Plan”) for the benefit of certain of its officers, directors and employees. In connection with the Separation, those employees of Harvard Bioscience who became employees of Biostage were allowed to continue vesting in their stock-based awards of stock options and restricted stock units granted under the Harvard Bioscience Plan. Accordingly, the Company recognized compensation expense as services were provided by those employees through the time of their vesting. All stock-based awards granted to Biostage employees were fully vested as of January 1, 2017.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	7. On April 14, 2017, representatives for the estate of a deceased individual filed a civil lawsuit in the Suffolk Superior Court, in Boston, Massachusetts, against the Company, Harvard Bioscience and other defendants. The complaint alleges that the decedent was harmed by two tracheal implants that incorporated synthetic trachea scaffolds and a biologic component combined by the implanting surgeon with a bioreactor, and surgically implanted in the decedent in two surgeries performed in 2012 and 2013, which harm caused her injury and death. The civil complaint seeks a non-specific sum of money to compensate the plaintiffs. This civil lawsuit relates to the Company’s first generation trachea scaffold technology for which the Company discontinued development in 2014, and not to the Company’s current Cellframe technology nor to its lead development product candidate, the Cellspan esophageal implant. The litigation is at an early stage and the Company intends to vigorously defend this case. While the Company believes that such claim lacks merit, and has filed a motion seeking dismissal of the lawsuit, the Company is unable to predict the ultimate outcome of such litigation. In accordance with a separation and distribution agreement between Harvard Bioscience and the Company relating to the Separation, the Company would be required to indemnify Harvard Bioscience against losses that Harvard Bioscience may suffer as a result of this litigation. The Company has been informed by its insurance provider that the case has been accepted as an insurable claim under the Company’s product liability insurance policy. From time to time, the Company may be involved in various claims and legal proceedings arising in the ordinary course of business. Other than the above matter, there are no such matters pending that the Company expects to be material in relation to its business, financial condition, and results of operations or cash flows.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events [Text Block]	8. Subsequent Events NASDAQ Delisting and OTCQB Quotation On October 4, 2017, following the withdrawal by the Company of its appeal to the NASDAQ Hearings Panel, the Company received written notification from NASDAQ indicating that the Panel had determined to delist the Company’s common stock from The NASDAQ Capital Market, and suspended the stock’s trading on that marketplace effective with the open of business on October 6, 2017. NASDAQ also informed the Company that it would file a Form 25-NSE with the SEC to formally remove the Company’s common stock from listing on NASDAQ, which was filed with the SEC on December 7, 2017. The Company’s common stock began trading on the OTCQB marketplace at the open of business on October 6, 2017. The Company’s common stock continues to trade under the symbol “BSTG”. First Pecos Breach Notice On October 5, 2017, the Company delivered a notice to First Pecos and its manager, Leon “Chip” Greenblatt III, stating that First Pecos was in breach of the Purchase Agreement, as described in note 3, as a result of its failure to deliver the Purchase Price to the Company following satisfaction of all closing conditions in the Purchase Agreement. None of the shares of common stock, shares of Preferred Stock or Warrants were issued to First Pecos. On termination fee pursuant to the terms of the Purchase Agreement. The Company believes that it was not in breach of the Purchase Agreement at any time, and that First Pecos’ notice was unjustified and without any legal merit or factual basis. Accordingly, the Company believes that Pecos was not entitled to terminate the Purchase Agreement, and is not entitled to any termination fee thereunder, as the failure to consummate the Pecos Placement resulted from First Pecos’ breach of the Purchase Agreement. The Company is reviewing all of its rights and remedies against First Pecos that may be available to the Company. Headcount Reduction During October and November, 2017, the Company completed a reduction in headcount of 21 of its employees, which represents 78% of its employees prior to such reduction. The reduction s ere Bioreactor Sale to Harvard Bioscience On November 3, 2017, in exchange for settlement of outstanding rent due to Harvard Bioscience, Biostage sold all of its current stock of research bioreactor parts, a royalty free perpetual sublicensable and transferable right and license to use the intellectual property, including but not limited to certain patents covering research bioreactors, and relinquished exclusive manufacturing or distribution rights with respect to research bioreactors to Harvard Bioscience. The Company had ceased the manufacture of research bioreactors in late 2016, to concentrate its efforts solely development of its clinical product candidates. This settlement only covers research bioreactors, not to be used for clinical purposes. The Company retains full exclusive rights to all assets and rights associated with the clinical bioreactor used in the development of the Company’s current Cellframe technology. December 2017 Private Placement MOU On December 11, 2017, the Company entered into a binding Memorandum of Understanding (the “MOU”) with Bin Zhao, pursuant to which the Company will issue to Ms. Ms. Additionally, Ms. Ms. The investor advanced a $300,000 deposit on the private placement proceeds concurrently with the MOU’s execution. The Preferred Stock will be entitled to vote on any matters to which shares of the Company’s common stock are entitled to vote, on an as-if-converted basis. The Preferred Stock will include an ownership limitation that will limit Ms. Ms. Ms. Ms. Pursuant to the MOU, the Company may identify other investors who may participate in the Private Placement on the same financial terms as Ms. Ms. Ms. The Private Placement is conditioned on satisfaction of customary closing conditions and on the Company completing a reverse stock split, as previously approved by its stockholders, such that the Company will have sufficient authorized but unissued shares of common stock to accommodate the issuance of shares of common stock in the Private Placement, along with all shares of common stock issuable upon exercise of the Warrants or conversion of the Preferred Stock. The numbers of securities, purchase price per share of common stock and exercise price of the Warrants will be adjusted to reflect such reverse stock split. The definitive agreements relating to the Private Placement will include customary representations, warranties and covenants. The MOU is intended to be binding upon both the Company and Ms.

Summary of Significant Accoun14

Summary of Significant Accounting Policies and Recently Issued Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation The financial statements reflect the Company’s financial position, results of operations and cash flows in conformity with accounting principles generally accepted in the United States (“GAAP”).
Earnings Per Share, Policy [Policy Text Block]	Net loss per Share Basic net loss per share is computed using the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed using the sum of the weighted average number of common shares outstanding during the period and, if dilutive, the weighted average number of potential shares of common stock, including the assumed exercise of stock options, warrants, and the impact of unvested restricted stock. The Company applies the two-class method to calculate basic and diluted net loss per share attributable to common stockholders as its warrants to purchase common stock are participating securities. The two-class method is an earnings allocation formula that treats a participating security as having rights to earnings that otherwise would have been available to common stockholders. However, the two-class method does not impact the net loss per share of common stock as the Company has been in a net loss position and the warrant holders do not participate in losses. Basic and diluted shares outstanding are the same for each period presented as all common stock equivalents would be antidilutive due to the net losses incurred.
Interim Financial Information [Policy Text Block]	Unaudited Interim Financial Information The accompanying interim consolidated balance sheet as of September 30, 2017 and consolidated interim statements of operations and comprehensive loss and cash flows for the three and nine months ended September 30, 2017 and 2016 are unaudited. The interim unaudited consolidated financial statements have been prepared in accordance with GAAP on the same basis as the annual audited financial statements and, in the opinion of management, reflect all adjustments necessary for a fair statement of the Company’s financial position as of September 30, 2017 and its results of operations and cash flows for the three and nine month periods ended September 30, 2017 and 2016. The financial data and other information disclosed in these notes related to the three and nine month periods ended September 30, 2017 and 2016 are unaudited. The results for the three and nine months ended September 30, 2017 are not necessarily indicative of results to be expected for the year ending December 31, 2017, any other interim periods or any future year or period.

Capital Stock, Financing and 15

Capital Stock, Financing and Liquidity (Tables)	9 Months Ended
	Sep. 30, 2017
Stockholders Equity Note [Abstract]
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]	The Company has issued warrants to purchase common stock, and the warrant activity during the nine months ended September 30, 2017 was as follows: Warrants Amount Weighted-average Outstanding at December 31, 2016 1,560,284 $ 1.76 Granted 21,000,000 0.40 Exercised (2,647,338) 0.40 Outstanding at September 30, 2017 19,912,946 $ 0.49

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Table Text Block]	Assumptions for estimating fair value of warrants Assumptions for estimating fair value on reporting September 30, 2017 June 30, 2017 September 30, 2017 December 31, 2016 Risk-free interest rate 1.89 % 1.77 % 1.93 % 1.93 % Expected volatility 82.3 % 82.4 % 85.0 % 72.7 % Expected term (in years) 4.6 4.6 4.4 4.9 Expected dividend yield - - - - Exercise price $ 0.40 $ 0.50 $ 0.40 $ 1.76 Market value of common stock $ 0.41 $ 0.33 $ 0.31 $ 0.89 Warrants to purchase shares of common stock 2,002,037 16,568,846 1,844,250 1,560,284
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The following fair value hierarchy table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of September 30, 2017: Fair Value Measurement as of September 30, 2017 (In thousands) Level 1 Level 2 Level 3 Total Warrant liability $ - $ - $ 339 $ 339 Total $ - $ - $ 339 $ 339 The following fair value hierarchy table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2016: Fair Value Measurement as of December 31, 2016 (In thousands) Level 1 Level 2 Level 3 Total Warrant liability $ - $ - $ 605 $ 605 Total $ - $ - $ 605 $ 605
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The following table presents a reconciliation of the Company’s liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the nine months ended September 30, 2017: Warrant Liability (in thousands) Balance at December 31, 2016 $ 605 Issuance of warrants 3,787 Change in fair value upon re-measurement 274 Reclassification of warrant liability to additional paid in capital upon modification (3,746) Reclassification of warrant liability to additional paid in capital upon exercise (581) Balance at September 30, 2017 $ 339

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2017
Stock Based Compensation [Line Items]
Schedule of Share-based Compensation, Activity [Table Text Block]	Stock option and restricted stock unit activity during the nine months ended September 30, 2017 was as follows: Stock Options Restricted Stock Units Amount Weighted-average exercise price Amount Weighted -average grant date fair value Outstanding at December 31, 2016 3,877,681 $ 2.81 268 $ 6.00 Granted 1,896,500 0.40 404,750 0.38 Vested (RSUs) - - (268 ) 6.00 Canceled (569,865 ) 1.67 - - Outstanding at September 30, 2017 5,204,316 $ 2.05 404,750 $ 0.38
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	The weighted average assumptions for valuing the options granted during the nine months ended September 30, 2017 were as follows: Expected volatility 78.71 % Expected dividends 0.00 % Expected term 6.26 years Risk-free rate 2.25 %
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]	The Company recorded equity-based compensation expense in the following expense categories of its consolidated statements of operations: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (in thousands) (in thousands) Research and development $ 98 $ 198 $ 281 $ 535 General and administrative 96 164 310 492 Total stock-based compensation $ 194 $ 362 $ 591 $ 1,027

Capital Stock, Financing and 18

Capital Stock, Financing and Liquidity (Details)	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Class of Warrant or Right [Line Items]
Warrants Amount, Outstanding | shares	1,560,284
Warrants Amount, Granted | shares	21,000,000
Warrants Amount, Exercised | shares	(2,647,338)
Warrants Amount, Outstanding | shares	19,912,946
Weighted-average exercise price, Outstanding | $ / shares	$ 1.76
Weighted-average exercise price, Granted | $ / shares	0.40
Weighted-average exercise price, Exercised | $ / shares	0.40
Weighted-average exercise price, Outstanding | $ / shares	$ 0.49

Capital Stock, Financing and 19

Capital Stock, Financing and Liquidity (Details Textual) - USD ($)	Aug. 11, 2017	Feb. 10, 2017	May 12, 2016	Dec. 15, 2015	Dec. 11, 2017	Jun. 26, 2017	May 19, 2016	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Jun. 29, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Proceeds from Issuance of Common Stock									$ 9,000	$ 349,000
Share Price								$ 0.31	$ 0.31			$ 0.89
Proceeds from Issuance or Sale of Equity									$ 6,801,000	$ 4,496,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights								1,844,250	1,844,250			1,560,284
Class of Warrant or Right, Exercise Price of Warrants or Rights								$ 0.49	$ 0.49			$ 1.76
Retained Earnings (Accumulated Deficit)								$ (47,005,000)	$ (47,005,000)			$ (36,318,000)
Memorandum of Understanding, Private Placement, Description									On June 26, 2017, the Company entered into a binding Memorandum of Understanding (the “MOU”) with First Pecos, LLC (“First Pecos”), pursuant to which the Company would issue to First Pecos in a private placement (the “Private Placement”) 9,700,000 shares of its common stock at a purchase price of $0.315 per share or, to the extent First Pecos, following the transaction, would own more than 19.9% of the Company’s common stock, shares of a new class of preferred stock of the Company (the “Preferred Stock”) with a per-share purchase price of $1,000.
Bid Price Per Share											$ 1
Minimum Net Capital Required											$ 2,500,000
Maximum [Member]
Class of Stock [Line Items]
Stockholders Equity, Reverse Stock Split									1-for-20
Minimum [Member]
Class of Stock [Line Items]
Stockholders Equity, Reverse Stock Split									1-for-2
First Pecos, LLC [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues	9,700,000
Proceeds from Issuance or Sale of Equity	$ 3,055,500
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	9,700,000					9,700,000
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 0.315
Preferred Stock, Dividend Rate, Percentage						15.00%
Termination Fee Payable						$ 500,000
Minimum Ownership Percentage In Common Shares	19.99%
First Pecos, LLC [Member] | Maximum [Member]
Class of Stock [Line Items]
Proceeds from Issuance of Private Placement						$ 14,000,000
Purchase Agreement [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues		20,000,000					2,836,880
Shares Issued, Price Per Share							$ 1.7625
Proceeds from Issuance of Common Stock		$ 6,800,000
Share Price		$ 0.40
Proceeds from Issuance or Sale of Equity							$ 4,600,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		20,000,000					1,418,440
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.40					$ 1.7625
Stock Issued During Period, Value, New Issues		$ 8,000,000					$ 5,000,000
Class Of Warrant Or Right Expiration Date							May 19, 2021
Class of Warrant or Right, Date from which Warrants or Rights Exercisable							Nov. 19, 2016
Purchase Agreement [Member] | Placement Agent [Member]
Class of Stock [Line Items]
Proceeds from Issuance of Common Stock								$ 1,100,000	$ 1,100,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		1,000,000					141,844	2,647,338	2,647,338
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.50					$ 1.7625
Aspire Purchase Agreement [Member]
Class of Stock [Line Items]
Stock Purchase Agreement, Value Committed				$ 15,000,000
Stock Issued During Period, Shares, Issued for Services				150,000
Stock Issued During Period, Shares, New Issues			150,000	500,000
Shares Issued, Price Per Share				$ 2
Proceeds from Issuance of Common Stock				$ 900,000
Proceeds from Issuance or Sale of Equity			$ 350,000
Stock Issued During Period, Value, New Issues			$ 370,000
Subsequent Event [Member]
Class of Stock [Line Items]
Shares Issued, Price Per Share					$ 0.10
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 0.10
Proceeds from Issuance of Private Placement					$ 2,000,000
Common Stock [Member] | First Pecos, LLC [Member]
Class of Stock [Line Items]
Shares Issued, Price Per Share	$ 0.315
Preferred Stock [Member] | First Pecos, LLC [Member]
Class of Stock [Line Items]
Shares Issued, Price Per Share	$ 1,000

Fair Value Measurements (Detail

Fair Value Measurements (Details) - $ / shares	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate			1.93%	1.93%
Expected volatility			85.00%	72.70%
Expected term (in years)			4 years 4 months 24 days	4 years 10 months 24 days
Expected dividend yield				0.00%
Exercise price	$ 0.49		$ 0.49	$ 1.76
Market value of common stock	$ 0.31		$ 0.31	$ 0.89
Warrants to purchase shares of common stock	1,844,250		1,844,250	1,560,284
Assumption for Estimating Fair Value,Warrants Modification [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	1.89%	1.77%
Expected volatility	82.30%	82.40%
Expected term (in years)	4 years 7 months 6 days	4 years 7 months 6 days
Expected dividend yield	0.00%	0.00%
Exercise price	$ 0.40	$ 0.50	$ 0.40
Market value of common stock	$ 0.41	$ 0.33	$ 0.41
Warrants to purchase shares of common stock	2,002,037	16,568,846	2,002,037

Fair Value Measurements (Deta21

Fair Value Measurements (Details 1) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	$ 339	$ 605
Warrant liability [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	339	605
Fair Value, Inputs, Level 1 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	0	0
Fair Value, Inputs, Level 1 [Member] | Warrant liability [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	0	0
Fair Value, Inputs, Level 2 [Member] | Warrant liability [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	339	605
Fair Value, Inputs, Level 3 [Member] | Warrant liability [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement, Total	$ 339	$ 605

Fair Value Measurements (Deta22

Fair Value Measurements (Details 2) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Balance at December 31, 2016	$ 605
Issuance of warrants	3,787
Change in fair value upon re-measurement	274
Reclassification of warrant liability to additional paid in capital upon modification	(3,746)
Reclassification of warrant liability to additional paid in capital upon exercise	(581)
Balance at September 30, 2017	$ 339

Fair Value Measurements (Deta23

Fair Value Measurements (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2017	Sep. 30, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Class of Warrant or Right, Issuance Cost	$ 385,000
Warrants To Be Modified, Number		19,043,696
Adjustments to Additional Paid in Capital, Warrants Modified		$ 4,300,000
Warrants To Be Re-measured, Number		1,844,250

Relationship with Harvard Bio24

Relationship with Harvard Bioscience (Details Textual) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
	Oct. 31, 2013	Sep. 30, 2017
Related Party Transaction [Line Items]
Product Distribution Agreement Term	10 years
Harvard Bioscience [Member]
Related Party Transaction [Line Items]
Proceeds from Contributions from Parent	$ 15
Accounts Receivable [Member] | Harvard Bioscience [Member]
Related Party Transaction [Line Items]
Concentration Risk, Percentage		100.00%

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - Biostage 2013 Equity Incentive Plan [Member]	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Options Amount, Balance | shares	3,877,681
Stock Options Amount, Granted | shares	1,896,500
Stock Options Amount, Vested (RSUs) | shares	0
Stock Options Amount, Cancelled | shares	(569,865)
Stock Options Amount, Balance | shares	5,204,316
Weighted-average exercise price, Balance | $ / shares	$ 2.81
Weighted-average exercise price, Granted | $ / shares	0.40
Weighted-average exercise price, Vested (RSUs) | $ / shares	0
Weighted-average exercise price, Cancelled | $ / shares	1.67
Weighted-average exercise price, Balance | $ / shares	$ 2.05
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Units Amount, Balance | shares	268
Restricted Stock Units Amount, Granted | shares	404,750
Restricted Stock Units Amount, Vested (RSUs) | shares	(268)
Restricted Stock Units Amount, Cancelled | shares	0
Restricted Stock Units Amount, Balance | shares	404,750
Weighted-average grant date fair value, Balance | $ / shares	$ 6
Weighted-average grant date fair value, Granted | $ / shares	0.38
Weighted-average grant date fair value, Vested (RSUs) | $ / shares	6
Weighted-average grant date fair value, Cancelled | $ / shares	0
Weighted-average grant date fair value, Balance | $ / shares	$ 0.38

Stock-Based Compensation (Det26

Stock-Based Compensation (Details 1) - Biostage 2013 Equity Incentive Plan [Member]	9 Months Ended
	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	78.71%
Expected dividends	0.00%
Expected term	6 years 3 months 4 days
Risk-free rate	2.25%

Stock-Based Compensation (Det27

Stock-Based Compensation (Details 2) - Biostage 2013 Equity Incentive Plan [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation	$ 194	$ 362	$ 591	$ 1,027
Research and Development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation	98	198	281	535
General and Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation	$ 96	$ 164	$ 310	$ 492

Subsequent Events (Details Text

Subsequent Events (Details Textual)	Oct. 10, 2017USD ($)	Dec. 11, 2017USD ($)$ / sharesshares	Nov. 30, 2017USD ($)	Sep. 30, 2017$ / shares	Jun. 26, 2017$ / shares	Dec. 31, 2016$ / shares
Subsequent Event [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares				$ 0.49		$ 1.76
First Pecos, LLC [Member]
Subsequent Event [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares					$ 0.315
Subsequent Event [Member]
Subsequent Event [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares		$ 0.10
Restructuring and Related Cost, Number of Positions Eliminated			21
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent			78.00%
Restructuring and Related Cost, Expected Cost | $			$ 165,000
Stock Issued During Period, Shares, Other | shares		40,000,000
Shares Issued, Price Per Share | $ / shares		$ 0.10
Equity Method Investment, Ownership Percentage		49.99%
Preferred Stock Shares Purchase Price		1000.00%
Warrants To Purchase Common Stock Shares | shares		60,000,000
Proceeds from Issuance of Private Placement | $		$ 2,000,000
Reduction Of Salaries Percentage			50.00%
Subsequent Event [Member] | Investor [Member]
Subsequent Event [Line Items]
Proceeds from Issuance of Private Placement | $		$ 300,000
Subsequent Event [Member] | First Pecos, LLC [Member]
Subsequent Event [Line Items]
Loss Contingency, Damages Sought, Value | $	$ 500,000