T2 Biosystems (TTOO) 10-Q 6 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	4-May-15
Document and Entity Information
Entity Registrant Name	T2 Biosystems, Inc.
Entity Central Index Key	1492674
Document Type	10-Q
Document Period End Date	31-Mar-15
Amendment Flag	FALSE
Current Fiscal Year End Date	-19
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		20,255,909
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$65,295	$73,849
Accounts receivable	88	201
Prepaid expenses and other current assets	686	1,076
Inventories	252	115
Restricted cash	80	80
Total current assets	66,401	75,321
Property and equipment, net	5,332	2,760
Restricted cash, net of current portion	260	260
Deferred tax assets	313	313
Other assets	468	480
Total assets	72,774	79,134
Current liabilities:
Accounts payable	1,173	735
Accrued expenses	3,426	3,662
Notes payable	300	295
Deferred revenue	2,029	80
Deferred tax liabilities	313	313
Lease incentives	214	87
Total current liabilities	7,455	5,172
Notes payable, net of current portion	20,592	20,660
Lease incentives, net of current portion	995	106
Other liabilities	252	195
Commitments and contingencies (Note 13)
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized; no shares issued and outstanding
Common stock, $0.001 par value; 200,000,000 at March 31, 2015 and December 31, 2014, respectively; 20,198,969 and 20,041,645 shares issued and outstanding at March 31, 2015 and December 31, 2014, respectively	20	20
Additional paid-in capital	157,673	156,576
Accumulated deficit	-114,213	-103,595
Total stockholders' equity	43,480	53,001
Total liabilities and stockholders' equity	$72,774	$79,134

Consolidated_Balance_Sheet_Par

Consolidated Balance Sheet (Parentheticals) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Consolidated Balance Sheets
Preferred stock, par value (in dollars per share)	$0.00	$0.00
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	20,198,969	20,041,645
Common stock, shares outstanding	20,198,969	20,041,645

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations and Comprehensive Loss (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements of Operations and Comprehensive Loss
Product revenue	$10
Research revenue	178
Total revenue	188
Costs and expenses:
Cost of product revenue	3
Research and development	5,868	5,065
Selling, general and administrative	4,468	1,842
Total costs and expenses	10,339	6,907
Loss from operations	-10,151	-6,907
Interest expense, net	-477	-86
Other income, net	9	73
Net loss	-10,619	-6,920
Comprehensive loss	-10,619	-6,920
Reconciliation of net loss to net loss applicable to common stockholders:
Net loss	-10,619	-6,920
Accretion of redeemable convertible preferred stock to redemption value		-1,906
Net loss applicable to common stockholders	($10,619)	($8,826)
Net loss per share applicable to common stockholders - basic and diluted	($0.53)	($6.25)
Weighted-average number of shares of common stock used in computing net loss per share applicable to common stockholders - basic and diluted	20,080,515	1,411,961

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Operating activities
Net loss	($10,619)	($6,920)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	253	144
Stock-based compensation expense	722	239
Noncash interest expense	24	11
Change in fair value of warrants		-73
Deferred rent	-18	-6
Changes in operating assets and liabilities:
Accounts receivable	113
Prepaid expenses and other current assets	390	-52
Inventories	-137
Accounts payable	438	93
Accrued expenses and other liabilities	-509	773
Deferred revenue	1,949
Net cash used in operating activities	-7,394	-5,791
Investing activities
Purchases of property and equipment	-1,460	-263
Net cash used in investing activities	-1,460	-263
Financing activities
Proceeds from issuance of common stock in initial public offering, net of offering costs	375
Repayments of notes payable	-75	-446
Net cash provided by (used in) financing activities	300	-446
Net (decrease) in cash and cash equivalents	-8,554	-6,500
Cash and cash equivalents at beginning of period	73,849	30,198
Cash and cash equivalents at end of period	65,295	23,698
Supplemental disclosures of cash flow information
Cash paid for interest	321	51
Supplemental disclosures of noncash investing and financing activities
Accrued costs of property and equipment	1,365
Accretion of Series A-1, A-2, B, C, D and E redeemable convertible preferred stock to redemption value		$1,906

Nature_of_Business

Nature of Business	3 Months Ended
	Mar. 31, 2015
Nature of Business
Nature of Business	1. Nature of Business
	T2 Biosystems, Inc. (the “Company”) was incorporated on April 27, 2006 as a Delaware corporation with operations based in Lexington, Massachusetts. The Company is an in vitro diagnostic company that has developed an innovative and proprietary platform that enables rapid, sensitive and simple direct detection of pathogens, biomarkers and other abnormalities across a variety of unpurified patient sample types. The Company is using its T2 Magnetic Resonance platform (“T2MR”) to develop a broad set of applications aimed at reducing mortality rates, improving patient outcomes and reducing the cost of healthcare by helping medical professionals make targeted treatment decisions earlier. The Company’s initial development efforts target sepsis, hemostasis and Lyme disease, areas of significant unmet medical need in which existing therapies could be more effective with improved diagnostics. On September 22, 2014, the Company received market authorization from the U.S. Food and Drug Administration (“FDA”) for its first two products, the T2Dx diagnostic instrument (“T2Dx”) and T2Candida panel (“T2Candida”).
	The Company has devoted substantially all of its efforts to research and development, business planning, recruiting management and technical staff, acquiring operating assets, raising capital, and, most recently, preparing of the commercialization of its products.
	Liquidity
	At March 31, 2015 the Company has an accumulated deficit of $114.2 million. The future success of the Company is dependent on its ability to successfully commercialize its newly authorized products, obtain regulatory clearance for and successfully launch its future product candidates and ultimately attain profitable operations, and obtain additional capital, if needed. Historically, the Company has funded its operations primarily through its August 2014 initial public offering, private placements of redeemable convertible preferred stock and through debt financing arrangements. Management believes that its existing cash resources at March 31, 2015 together with the additional remaining liquidity of up to $10.0 million of available borrowings from existing debt facilities (Note 5) will be sufficient to allow the Company to fund its current operating plan through at least the next 12 months.
	The Company is subject to a number of risks similar to other newly commercial life science companies, including, but not limited to commercially launching the Company’s products, development and market acceptance of the Company’s product candidates, development by its competitors of new technological innovations, protection of proprietary technology, and raising additional capital.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2015
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies
	Basis of Presentation
	The Company’s financial statements have been prepared in conformity with generally accepted accounting principles in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States GAAP as defined in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).  The Company’s condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary, T2 Biosystems Securities Corporation.  All intercompany balances and transactions have been eliminated.
	Unaudited Interim Financial Information
	Certain information and footnote disclosures normally included in the Company’s annual financial statement have been condensed or omitted.  Accordingly, these interim condensed consolidated financial statements should be read in conjunction with the financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.
	The accompanying interim condensed consolidated balance sheet as of March 31, 2015, the condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2015 and 2014, the condensed consolidated statements of cash flows for the three months ended March 31, 2015 and 2014 and the related financial data and other information disclosed in these notes are unaudited. The unaudited interim financial statements have been prepared on the same basis as the audited annual financial statements, and, in the opinion of management, reflect all adjustments, consisting of normal recurring adjustments, necessary for the fair presentation of the Company’s financial position as of March 31, 2015, and the results of its operations and its cash flows for the three months ended March 31, 2015 and 2014. The results for the three months ended March 31, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015, any other interim periods, or any future year or period.
	Segment Information
	Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing the enterprise’s performance. The Company’s chief operating decision maker is the Chief Executive Officer. The Company views its operations and manages its business in one operating segment, which is the business of developing and launching commercially its diagnostic products aimed at reducing mortality rates, improving patient outcomes and reducing the cost of healthcare by helping medical professionals make targeted treatment decisions earlier.
	Net Loss Per Share
	Basic net loss per share is calculated by dividing net loss applicable to common stockholders, which is net loss plus accretion of redeemable convertible preferred stock to redemption value in the period, by the weighted-average number of shares of common stock outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share is calculated by adjusting the weighted-average number of shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method for outstanding stock options and warrants. For purposes of the diluted net loss per share calculation, redeemable convertible preferred stock, warrants to purchase redeemable convertible preferred stock and stock options are considered to be common stock equivalents, but have been excluded from the calculation of diluted net loss per share, as their effect, including the related impact to the numerator of the fair value adjustment of the warrant and the impact to the denominator of the warrant shares, would be anti-dilutive for all periods presented. Therefore, basic and diluted net loss per share applicable to common stockholders was the same for all periods presented.
	Guarantees
	From time to time, the Company enters into indemnification agreements in the ordinary course of business, including, but not limited to, indemnification agreements with directors and officers, within its lease agreements for office, laboratory and manufacturing space, and with certain suppliers and business partners.  As of March 31, 2015 and December 31, 2014, the Company had not experienced any material losses related to these indemnification obligations, and no material claims with respect thereto were outstanding. The Company does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible, and no related reserves were established.
	Revenue Recognition
	The Company generates revenue from product sales and research and development agreements with government agencies and other third parties. The Company recognizes revenue in accordance with FASB ASC Topic 605, Revenue Recognition (“ASC 605”). Accordingly, the Company recognizes revenue when all of the following criteria have been met:
		i.	Persuasive evidence of an arrangement exists
		ii.	Delivery has occurred or services have been rendered
		iii.	The seller’s price to the buyer is fixed or determinable
		iv.	Collectability is reasonably assured
	Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue.
	The Company offers customers the choice either to purchase a T2Dx outright or to receive possession of a T2Dx pursuant to a “reagent rental” agreement  wherein, the Company retains title to the T2DX and earn revenue for the usage of the instrument and related maintenance services through the amount charged for reagents.
	Revenue earned from activities performed pursuant to research and development agreements is reported as research revenue in the statements of operations and comprehensive loss, using the proportional performance method as the work is completed, and the related costs are expensed as incurred as research and development expense.  The timing of receipt of cash from the Company’s research and development agreements generally differs from when revenue is recognized.
	For multiple-element arrangements, the Company identifies the deliverables included within each agreement and evaluates which deliverables represent separate units of accounting. The Company accounts for those components as separate elements when the following criteria are met: (1) the delivered items have value to the customer on a stand-alone basis; and, (2) if there is a general right of return relative to the delivered items, delivery or performance of the undelivered items is considered probable and within its control.  The consideration received is allocated among the separate units of accounting based on management’s best estimate of selling price, and the applicable revenue recognition criteria are applied to each of the separate units. The determination that multiple elements in an arrangement meet the criteria for separate units of accounting requires the Company’s management to exercise its judgment.
	Recently Issued or Adopted Accounting Pronouncements
	From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its financial position or results of operations upon adoption.
	In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs (“ASU 2015-03”). This standard amends existing guidance to require the presentation of debt issuance costs in the balance sheet as a deduction from the carrying amount of the related debt liability instead of a deferred charge. It is effective for annual reporting periods beginning after December 15, 2015, but early adoption is permitted.  Adoption of ASU 2015-03 is applied retrospectively.  The Company has not adopted the guidance prescribed by ASU 2015-03 and does not expect the new guidance to have a material effect on its condensed consolidated financial statements.
	In June 2014, the FASB issued amended guidance, ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), which is applicable to revenue recognition that will be effective for the Company for the year ended December 31, 2017.  In April 2015, the FASB issued an exposure draft of a proposed ASU that would delay by one year the effective date of the new revenue recognition  standard, or until the year ended December 31, 2018 for the Company, if ratified. The new guidance must be adopted using either a full retrospective approach for all periods presented or a modified retrospective approach.  Early adoption prior to the original adoption date of ASU 2014-09 is not permitted.  The new guidance applies a more principles-based approach to revenue recognition.  The Company is evaluating the new guidance and the expected effect on the Company’s condensed consolidated financial statements.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2015
Fair Value Measurements
Fair Value Measurements
	3. Fair Value Measurements
	The Company measures the following financial assets at fair value on a recurring basis. The following tables set forth the Company’s financial assets carried at fair value categorized using the lowest level of input applicable to each financial instrument as of March 31, 2015 and December 31, 2014 (in thousands):
		Balance at		Quoted Prices		Significant		Significant
		March 31,		in Active		Other		Unobservable
		2015		Markets for		Observable		Inputs
				Identical		Inputs		(Level 3)
				Assets		(Level 2)
				(Level 1)
	Assets:
	Cash	$	2,294	$	2,294	$	—	$	—
	Money market funds	63,001		63,001		—		—
	Restricted cash	340		340		—		—
		$	65,635	$	65,635	$	—	$	—
		Balance at		Quoted Prices		Significant		Significant
		December 31,		in Active		Other		Unobservable
		2014		Markets for		Observable		Inputs
				Identical		Inputs		(Level 3)
				Assets		(Level 2)
				(Level 1)
	Assets:
	Cash	$	10,348	$	10,348	$	—	$	—
	Money market funds	63,501		63,501		—		—
	Restricted cash	340		340		—		—
		$	74,189	$	74,189	$	—	$	—
	For certain financial instruments, including accounts payable and accrued expenses, the carrying amounts approximate their fair values as of March 31, 2015 and December 31, 2014 because of their short-term nature. At March 31, 2015 and December 31, 2014, the carrying value of the Company’s debt approximated fair value, which was determined using Level 3 inputs, including a market interest rate.

Supplemental_Balance_Sheet_Inf

Supplemental Balance Sheet Information	3 Months Ended
	Mar. 31, 2015
Supplemental Balance Sheet Information
Supplemental Balance Sheet Information	4. Supplemental Balance Sheet Information
	Inventories
	Inventories are stated at the lower of cost or market value on a first-in, first-out basis and are comprised of the following (in thousands):
		March 31,			December 31,
		2015			2014
	Raw materials	$	111		$	71
	Work-in-process	141			44
	Total inventories	$	252		$	115
	Property and Equipment
	Property and equipment consists of the following (in thousands):
		March 31,			December 31,
		2015			2014
	Office and computer equipment	$	384		$	383
	Software	505			480
	Laboratory equipment	3,380			3,312
	Furniture	187			187
	Manufacturing tooling and molds	26			26
	Leasehold improvements	833			764
	Construction in progress	2,428			387
	T2Dx instruments and components	1,184			563
		8,927			6,102
	Less accumulated depreciation and amortization	(3,595		)	(3,342		)
	Property and equipment, net	$	5,332		$	2,760
	Construction in progress is primarily comprised of equipment and leasehold improvement construction projects that have not been placed in service.  T2Dx instruments and components is comprised of raw materials and work-in-process inventory that are expected to be used or used to produce Company-owned instruments, based on our business model and forecast, and completed instruments that will be used for internal research and development or reagent rental agreements with customers.  Such completed instruments have not yet been placed in service.
	Accrued Expenses
	Accrued expenses consist of the following (in thousands):
		March 31,			December 31,
		2015			2014
	Accrued payroll and compensation	$	1,457		$	1,846
	Accrued professional services	428			374
	Accrued research and development expenses	635			733
	Other accrued expenses	906			709
	Total accrued expenses	$	3,426		$	3,662

Debt

Debt	3 Months Ended
	Mar. 31, 2015
Debt
Debt	5. Debt
	On July 11, 2014, the Company entered into a loan and security agreement (“Note Agreement”) with two lenders to borrow up to $30.0 million for operations. The Note Agreement allows the Company to borrow amounts in two tranches, up to $20.0 million (drawn in amounts not less than $10.0 million upon closing and the remainder drawn in amounts not less than $5.0 million draws) by December 31, 2014 for tranche A and up to $10.0 million by June 30, 2015 for tranche B. Under the Note Agreement, borrowings under tranche B are only available to the Company if both of the following conditions are met by June 30, 2015: (a) the Company receives Section 510(k) clearance from the FDA on the Company’s T2Dx and T2Candida products and (b) the Company completes a public or private stock offering, equity raise or strategic partner arrangement resulting in the receipt of at least $30.0 million in net proceeds by the Company. As the Company received FDA approval in September 2014 and the Company closed its initial public offering in August 2014, the borrowings under tranche B are now available as both of the required conditions have been met.
	Through March 31, 2015, the Company received proceeds of $19.7 million under tranche A, net of deferred financing costs. To date, the Company has not drawn the remaining tranche B available borrowings of $10.0 million.
	The amounts borrowed under the Note Agreement are collateralized by substantially all of the assets of the Company and bear interest at the one-month LIBOR plus 7.05%, which was 7.22% on March 31, 2015. The Company will pay interest only payments on the amounts borrowed under the Note Agreement through July 31, 2016. After the interest only period, the Company will repay the amounts borrowed in equal monthly installments until the maturity date of July 1, 2019. The Note Agreement requires payment of a final fee of 4.75% of the aggregate original principal of amounts borrowed, which the Company is accruing over the term of the Note Agreement. In addition, amounts borrowed may be prepaid at the option of the Company in denominations of not less than $1,000,000, and any amounts prepaid are subject to a prepayment premium of 1.5% if prepaid prior to the first anniversary of the borrowing date, 1.0% if prepaid prior to the second anniversary of the borrowing date and after the first anniversary of the borrowing date, and 0.5% if prepaid prior to the maturity date and after the second anniversary of the borrowing date.  The effective interest rate for the Note Agreement, including final fee interest and non-cash interest, is 9.3%.
	The Note Agreement does not include any financial covenants, but does contain a subjective acceleration clause whereby upon an event of default, which includes a material adverse change in the business, operations, or conditions (financial or otherwise) of the Company or a material impairment of the prospect of repayment of any portion of the obligations, the lender may accelerate the Company’s repayment obligations under the Note Agreement. In the event of default, the lender has first priority to substantially all of the Company’s assets.  The lender has not exercised its right under this clause, as there have been no such events. The Company believes the likelihood of the lender exercises this right is remote.
	The Company assessed all terms and features of the Note Agreement in order to identify any potential embedded features that would require bifurcation or any beneficial conversion features. As part of this analysis, the Company assessed the economic characteristics and risks of the Note Agreement, including put and call features. The Company determined that all features of the Note Agreement are clearly and closely associated with a debt host and do not require bifurcation as a derivative liability, or the fair value of the feature is immaterial. The Company will continue to reassess the features to determine if they require separate accounting on a quarterly basis.

Stockholders_Equity_10Q

Stockholders' Equity - 10Q	3 Months Ended
	Mar. 31, 2015
Stockholders' Equity
Stockholders' Equity	6. Stockholders’ Equity
	Stock-Based Compensation
	2006 Stock Incentive Plan
	The Company’s 2006 Stock Option Plan (“2006 Plan”) was established for granting stock incentive awards to directors, officers, employees and consultants of the Company.  Upon closing of the Company’s IPO in August 2014, the Company ceased granting stock incentive awards under the 2006 Plan.  The 2006 Plan provided for the grant of incentive and non-qualified stock options and restricted stock grants as determined by the Company’s board of directors.  Under the 2006 Plan, stock options were generally granted with exercise prices equal to or greater than the fair value of the common stock as determined by the board of directors, expired no later than 10 years from the date of grant, and vest over various periods not exceeding 4 years.
	2014 Stock Incentive Plan
	The Company’s 2014 Plan (“2014 Plan”, and together with the 2016 Plan, the “Plans”) provides for the issuance of shares of common stock in the form of stock options, awards of restricted stock, awards of restricted stock units, performance awards, dividend equivalent awards, stock payment awards and stock appreciation rights to directors, officers, employees and consultants of the Company. Since the establishment of the 2014 Plan, the Company has only granted stock options.  Generally, stock options are granted with exercise prices equal to or greater than the fair value of the common stock on the date of grant, expire no later than 10 years from the date of grant, and vest over various periods not exceeding 4 years.
	The number of shares reserved for future issuance under the 2014 Plan is the sum of (1) 823,529 shares, (2) any shares that were granted under the 2006 Plan which are forfeited, lapsed unexercised or are settled in cash subsequent to the effective date of the 2014 Plan and (3) an annual increase on the first day of each calendar year beginning January 1, 2015 and ending on January 1, 2024, equal to the lesser of (A) 823,529 shares, (B) 4% of the shares outstanding (on an as-converted basis) on the final day of the immediately preceding calendar year, and (C) such smaller number of shares determined by the Company’s board of directors.   As of March 31, 2015 there were 878,282 shares available for future grant under the 2014 Plan.
	Stock Options
	During the three months ended March 31, 2015, the Company granted options with an aggregate fair value of $5.0 million, which are being amortized into compensation expense over the vesting period of the options as the services are being provided. The following is a summary of option activity under the Plans:
		Number of		Weighted-Average			Weighted-Average	Aggregate Intrinsic
		Shares		Exercise Price Per			Remaining	Value
				Share			Contractual Term	(In thousands)
							(In years)
	Outstanding at December 31, 2014	2,911,146		$	5.3		7.87	$	40,586
	Granted	516,954		18.2
	Exercised	(157,324	)	2.38				2,067
	Cancelled	(46,724	)	7.97
	Outstanding at March 31, 2015	3,224,052		7.47			8.03	25,954
	Exercisable at March 31, 2015	1,543,881		2.74			6.56	19,733
	Vested or expected to vest at March 31, 2015	2,827,095		7.09			7.89	23,822
	The total fair values of stock options that vested during the three months ended March 31, 2015 and 2014 was $499,000 and $137,000, respectively.
	The weighted-average fair values of options granted in the three-month periods ended March 31, 2015 and 2014 were $9.75 per share and $5.73 per share, respectively, and were calculated using the following estimated assumptions:
		Three Months Ended
		March 31,
		2015		2014
	Weighted-average risk-free interest rate	1.70	%	2.04	%
	Expected dividend yield	0.00	%	0.00	%
	Expected volatility	56	%	62	%
	Expected terms	6.1 years		6.1 years
	Employee Stock Purchase Plan
	The Company’s 2014 Employee Stock Purchase Plan (the “2014 ESPP”) provides initially for granting up to 220,588 shares of the Company’s common stock to eligible employees.  The 2014 ESPP plan period is semi-annual and allows participants to purchase the Company’s common stock at 85% of the lower of (i) the market value per share of common stock on the first day of the offering period or (ii) the market value per share of the common stock on the purchase date.  Each participant can purchase up to a maximum of $25,000 per year in fair market value of such shares of common stock, as determined by the market value per share of common stock at the beginning of the offering period.  The first 2014 ESPP plan period began on August 7, 2014.  Stock-based compensation expense from the 2014 ESPP for the three-months ended March 31, 2015 was $60,000.
	Stock-Based Compensation Expense
	The following table summarizes the stock-based compensation expense for stock options granted to employees and nonemployees, as well as stock-based compensation expense for the 2014 ESPP that was recorded in the Company’s results of operations for the three months ended March 31, 2015 and 2014 (in thousands):
		Three Months
		Ended
		March 31,
		2015			2014
	Research and development	$	280		$	56
	Selling, general and administrative	442			183
	Total stock-based compensation expense	$	722		$	239
	As of March 31, 2015, there was $11,480,000 of total unrecognized compensation cost related to unvested stock options granted under the Plans. Total unrecognized compensation cost will be adjusted for future changes in the estimated forfeiture rate. The Company expects to recognize that cost over a remaining weighted-average period of 3.4 years as of March 31, 2015.

Net_Loss_Per_Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2015
Net Loss Per Share
Net Loss Per Share	7. Net Loss Per Share
	The following shares were excluded from the calculation of diluted net loss per share applicable to common stockholders, prior to the application of the treasury stock method, because the effect of including such shares would have been anti-dilutive for the periods presented:
		Three Months Ended
		March 31,
		2015	2014
	Redeemable convertible preferred stock	—	12,516,298
	Options to purchase common stock	3,224,052	2,282,591
	Warrants to purchase redeemable convertible preferred stock	—	147,484
	Total	3,224,052	14,946,373

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies.
Commitments and Contingencies	8. Commitments and Contingencies
	Lease Amendments
	In March 2015, the Company provided notice to the landlord of its intent to exercise the two year lease extension option for office and laboratory space at the Company’s headquarters in Lexington, MA.  The lease term will now extend to December 31, 2017.  The final terms of the lease extension period are still being finalized between the parties.
	In March 2015, the Company entered into an amendment to extend the term of an office space lease. The lease amendment extends the lease term to December 31, 2017 and the annual rent for the additional year is approximately $300,000.

CoDevelopment_Agreement_with_C

Co-Development Agreement with Canon US Life Sciences	3 Months Ended
	Mar. 31, 2015
Co-Development Agreement with Canon US Life Sciences
Development Agreement	9. Co-Development Agreement with Canon US Life Sciences
	On February 3, 2015, the Company entered into a Co-Development Partnership Agreement (“Agreement”) with Canon U.S. Life Sciences, Inc. (“Canon US Life Sciences”) to develop a diagnostic test panel to rapidly detect Lyme disease.  Under the terms of the Agreement, the Company received an upfront payment of $2.0 million from Canon US Life Sciences and may receive an additional $6.5 million of consideration upon achieving certain development and regulatory milestones for total aggregate payments of up to $8.5 million.  The next payment the Company is eligible to receive is $1.5 million related to the achievement of a specified technical requirement.  All payments under the Agreement are non-refundable once received.  The Company will retain exclusive worldwide commercialization rights of any products developed under the Agreement, including sales, marketing and distribution and Canon US Life Sciences will not receive any commercial right and will be entitled to only receive royalty payments on the sales of all products developed under the Agreement.
	Either party may terminate the Agreement upon the occurrence of a material breach by the other party (subject to a cure period).
	The Company evaluated the deliverables under the Agreement and determined that the Agreement included one unit of accounting, the research and development services, as the joint research and development committee deliverable was deemed to be de minimus.  The Company will recognize revenue for research and development services as a component of research revenue in the condensed consolidated financial statements as the services are delivered using the proportional performance method of accounting, limited to cash received. The regulatory milestone will be accounted for as research revenue if and when achieved. Costs incurred to deliver the services under the Agreement are recorded as research and development expense in the condensed consolidated financial statements.
	The Company recorded revenue of $53,000 during the three months ended March 31, 2015 under this Agreement.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2015
Summary of Significant Accounting Policies
Basis of Presentation	Basis of Presentation
	The Company’s financial statements have been prepared in conformity with generally accepted accounting principles in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States GAAP as defined in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).  The Company’s condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary, T2 Biosystems Securities Corporation.  All intercompany balances and transactions have been eliminated.
Unaudited Interim Financial Information	Unaudited Interim Financial Information
	Certain information and footnote disclosures normally included in the Company’s annual financial statement have been condensed or omitted.  Accordingly, these interim condensed consolidated financial statements should be read in conjunction with the financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.
	The accompanying interim condensed consolidated balance sheet as of March 31, 2015, the condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2015 and 2014, the condensed consolidated statements of cash flows for the three months ended March 31, 2015 and 2014 and the related financial data and other information disclosed in these notes are unaudited. The unaudited interim financial statements have been prepared on the same basis as the audited annual financial statements, and, in the opinion of management, reflect all adjustments, consisting of normal recurring adjustments, necessary for the fair presentation of the Company’s financial position as of March 31, 2015, and the results of its operations and its cash flows for the three months ended March 31, 2015 and 2014. The results for the three months ended March 31, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015, any other interim periods, or any future year or period.
Segment Information	Segment Information
	Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing the enterprise’s performance. The Company’s chief operating decision maker is the Chief Executive Officer. The Company views its operations and manages its business in one operating segment, which is the business of developing and launching commercially its diagnostic products aimed at reducing mortality rates, improving patient outcomes and reducing the cost of healthcare by helping medical professionals make targeted treatment decisions earlier.
Net Loss Per Share	Net Loss Per Share
	Basic net loss per share is calculated by dividing net loss applicable to common stockholders, which is net loss plus accretion of redeemable convertible preferred stock to redemption value in the period, by the weighted-average number of shares of common stock outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share is calculated by adjusting the weighted-average number of shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method for outstanding stock options and warrants. For purposes of the diluted net loss per share calculation, redeemable convertible preferred stock, warrants to purchase redeemable convertible preferred stock and stock options are considered to be common stock equivalents, but have been excluded from the calculation of diluted net loss per share, as their effect, including the related impact to the numerator of the fair value adjustment of the warrant and the impact to the denominator of the warrant shares, would be anti-dilutive for all periods presented. Therefore, basic and diluted net loss per share applicable to common stockholders was the same for all periods presented.
Guarantees	Guarantees
	From time to time, the Company enters into indemnification agreements in the ordinary course of business, including, but not limited to, indemnification agreements with directors and officers, within its lease agreements for office, laboratory and manufacturing space, and with certain suppliers and business partners.  As of March 31, 2015 and December 31, 2014, the Company had not experienced any material losses related to these indemnification obligations, and no material claims with respect thereto were outstanding. The Company does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible, and no related reserves were established.
Revenue Recognition	Revenue Recognition
	The Company generates revenue from product sales and research and development agreements with government agencies and other third parties. The Company recognizes revenue in accordance with FASB ASC Topic 605, Revenue Recognition (“ASC 605”). Accordingly, the Company recognizes revenue when all of the following criteria have been met:
		i.	Persuasive evidence of an arrangement exists
		ii.	Delivery has occurred or services have been rendered
		iii.	The seller’s price to the buyer is fixed or determinable
		iv.	Collectability is reasonably assured
	Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue.
	The Company offers customers the choice either to purchase a T2Dx outright or to receive possession of a T2Dx pursuant to a “reagent rental” agreement  wherein, the Company retains title to the T2DX and earn revenue for the usage of the instrument and related maintenance services through the amount charged for reagents.
	Revenue earned from activities performed pursuant to research and development agreements is reported as research revenue in the statements of operations and comprehensive loss, using the proportional performance method as the work is completed, and the related costs are expensed as incurred as research and development expense.  The timing of receipt of cash from the Company’s research and development agreements generally differs from when revenue is recognized.
	For multiple-element arrangements, the Company identifies the deliverables included within each agreement and evaluates which deliverables represent separate units of accounting. The Company accounts for those components as separate elements when the following criteria are met: (1) the delivered items have value to the customer on a stand-alone basis; and, (2) if there is a general right of return relative to the delivered items, delivery or performance of the undelivered items is considered probable and within its control.  The consideration received is allocated among the separate units of accounting based on management’s best estimate of selling price, and the applicable revenue recognition criteria are applied to each of the separate units. The determination that multiple elements in an arrangement meet the criteria for separate units of accounting requires the Company’s management to exercise its judgment.
Recently Issued or Adopted Accounting Pronouncements	Recently Issued or Adopted Accounting Pronouncements
	From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its financial position or results of operations upon adoption.
	In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs (“ASU 2015-03”). This standard amends existing guidance to require the presentation of debt issuance costs in the balance sheet as a deduction from the carrying amount of the related debt liability instead of a deferred charge. It is effective for annual reporting periods beginning after December 15, 2015, but early adoption is permitted.  Adoption of ASU 2015-03 is applied retrospectively.  The Company has not adopted the guidance prescribed by ASU 2015-03 and does not expect the new guidance to have a material effect on its condensed consolidated financial statements.
	In June 2014, the FASB issued amended guidance, ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), which is applicable to revenue recognition that will be effective for the Company for the year ended December 31, 2017.  In April 2015, the FASB issued an exposure draft of a proposed ASU that would delay by one year the effective date of the new revenue recognition  standard, or until the year ended December 31, 2018 for the Company, if ratified. The new guidance must be adopted using either a full retrospective approach for all periods presented or a modified retrospective approach.  Early adoption prior to the original adoption date of ASU 2014-09 is not permitted.  The new guidance applies a more principles-based approach to revenue recognition.  The Company is evaluating the new guidance and the expected effect on the Company’s condensed consolidated financial statements.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Measurements
Schedule of financial assets and liabilities at fair value on a recurring basis	The following tables set forth the Company’s financial assets carried at fair value categorized using the lowest level of input applicable to each financial instrument as of March 31, 2015 and December 31, 2014 (in thousands):
		Balance at		Quoted Prices		Significant		Significant
		March 31,		in Active		Other		Unobservable
		2015		Markets for		Observable		Inputs
				Identical		Inputs		(Level 3)
				Assets		(Level 2)
				(Level 1)
	Assets:
	Cash	$	2,294	$	2,294	$	—	$	—
	Money market funds	63,001		63,001		—		—
	Restricted cash	340		340		—		—
		$	65,635	$	65,635	$	—	$	—
		Balance at		Quoted Prices		Significant		Significant
		December 31,		in Active		Other		Unobservable
		2014		Markets for		Observable		Inputs
				Identical		Inputs		(Level 3)
				Assets		(Level 2)
				(Level 1)
	Assets:
	Cash	$	10,348	$	10,348	$	—	$	—
	Money market funds	63,501		63,501		—		—
	Restricted cash	340		340		—		—
		$	74,189	$	74,189	$	—	$	—

Supplemental_Balance_Sheet_Inf1

Supplemental Balance Sheet Information (Tables)	3 Months Ended
	Mar. 31, 2015
Supplemental Balance Sheet Information
Schedule of inventory	Inventories are stated at the lower of cost or market value on a first-in, first-out basis and are comprised of the following (in thousands):
		March 31,			December 31,
		2015			2014
	Raw materials	$	111		$	71
	Work-in-process	141			44
	Total inventories	$	252		$	115
Schedule of property and equipment	Property and equipment consists of the following (in thousands):
		March 31,			December 31,
		2015			2014
	Office and computer equipment	$	384		$	383
	Software	505			480
	Laboratory equipment	3,380			3,312
	Furniture	187			187
	Manufacturing tooling and molds	26			26
	Leasehold improvements	833			764
	Construction in progress	2,428			387
	T2Dx instruments and components	1,184			563
		8,927			6,102
	Less accumulated depreciation and amortization	(3,595		)	(3,342		)
	Property and equipment, net	$	5,332		$	2,760
Components of accrued expenses	Accrued expenses consist of the following (in thousands):
		March 31,			December 31,
		2015			2014
	Accrued payroll and compensation	$	1,457		$	1,846
	Accrued professional services	428			374
	Accrued research and development expenses	635			733
	Other accrued expenses	906			709
	Total accrued expenses	$	3,426		$	3,662

Stockholders_Equity_Tables_10Q

Stockholders' Equity (Tables) - 10Q	3 Months Ended
	Mar. 31, 2015
Stockholders' Equity
Summary of stock option activity		Number of		Weighted-Average			Weighted-Average	Aggregate Intrinsic
		Shares		Exercise Price Per			Remaining	Value
				Share			Contractual Term	(In thousands)
							(In years)
	Outstanding at December 31, 2014	2,911,146		$	5.3		7.87	$	40,586
	Granted	516,954		18.2
	Exercised	(157,324	)	2.38				2,067
	Cancelled	(46,724	)	7.97
	Outstanding at March 31, 2015	3,224,052		7.47			8.03	25,954
	Exercisable at March 31, 2015	1,543,881		2.74			6.56	19,733
	Vested or expected to vest at March 31, 2015	2,827,095		7.09			7.89	23,822
Schedule of estimated assumptions used to calculate weighted-average fair value of options granted		Three Months Ended
		March 31,
		2015		2014
	Weighted-average risk-free interest rate	1.70	%	2.04	%
	Expected dividend yield	0.00	%	0.00	%
	Expected volatility	56	%	62	%
	Expected terms	6.1 years		6.1 years
Summary of stock-based compensation expense for stock options granted that was recorded in the Company's results of operations	The following table summarizes the stock-based compensation expense for stock options granted to employees and nonemployees, as well as stock-based compensation expense for the 2014 ESPP that was recorded in the Company’s results of operations for the three months ended March 31, 2015 and 2014 (in thousands):
		Three Months
		Ended
		March 31,
		2015			2014
	Research and development	$	280		$	56
	Selling, general and administrative	442			183
	Total stock-based compensation expense	$	722		$	239

Net_Loss_Per_Share_Tables

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
Net Loss Per Share
Schedule of shares excluded from the calculation where the inclusion would be anti-dilutive
		Three Months Ended
		March 31,
		2015	2014
	Redeemable convertible preferred stock	—	12,516,298
	Options to purchase common stock	3,224,052	2,282,591
	Warrants to purchase redeemable convertible preferred stock	—	147,484
	Total	3,224,052	14,946,373

Nature_of_Business_Details

Nature of Business (Details) (USD $)	0 Months Ended
	Aug. 12, 2014	Mar. 31, 2015	Dec. 31, 2014	Jul. 11, 2014
Accumulated deficit		($114,213,000)	($103,595,000)
Note Agreement 1
Maximum borrowings available				30,000,000
IPO
Period over which cash resources will be sufficient to allow Company to fund current operating plan	12 months
IPO | Note Agreement 1
Maximum borrowings available				$10,000,000

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Details) - 10Q	3 Months Ended
	Mar. 31, 2015
	segment
Segment Information
Number of Operating Segments	1

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (Recurring, Fair value, USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets:
Restricted cash	$340	$340
Total assets	65,635	74,189
Cash
Assets:
Cash and cash equivalents	2,294	10,348
Money market funds
Assets:
Cash and cash equivalents	63,001	63,501
Level 1
Assets:
Restricted cash	340	340
Total assets	65,635	74,189
Level 1 | Cash
Assets:
Cash and cash equivalents	2,294	10,348
Level 1 | Money market funds
Assets:
Cash and cash equivalents	$63,001	$63,501

Supplemental_Balance_Sheet_Inf2

Supplemental Balance Sheet Information (Details) - 10Q (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Supplemental Balance Sheet Information
Raw materials	$111	$71
Work-in-process	141	44
Total inventories	$252	$115

Supplemental_Balance_Sheet_Inf3

Supplemental Balance Sheet Information (Details 2) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$8,927	$6,102
Accumulated depreciation and amortization	-3,595	-3,342
Property and equipment, net	5,332	2,760
Accrued expenses
Accrued payroll and compensation	1,457	1,846
Accrued professional services	428	374
Accrued research and development expenses	635	733
Other accrued expenses	906	709
Total accrued expenses	3,426	3,662
Office and computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	384	383
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	505	480
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,380	3,312
Furniture
Property, Plant and Equipment [Line Items]
Property and equipment, gross	187	187
Manufacturing tooling and molds
Property, Plant and Equipment [Line Items]
Property and equipment, gross	26	26
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	833	764
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,428	387
T2Dx instruments and components
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$1,184	$563

Debt_Details

Debt (Details) (Note Agreement 1, USD $)	0 Months Ended	3 Months Ended
	Jul. 11, 2014	Mar. 31, 2015	Jul. 11, 2014
	tranche
	Lender
Debt Instrument [Line Items]
Number of lenders	2
Maximum borrowings available	$30,000,000		$30,000,000
Number of tranches	2
Interest rate including both the variable rate and the basis spread (as a percent)		7.22%
Final fee as a percentage of original principal amount of amounts borrowed	4.75%		4.75%
Minimum amount of denomination for prepayment of borrowings	1,000,000		1,000,000
Effective interest rate including final fee interest and non-cash interest (as a percent)		9.30%
Prior to first anniversary of borrowing date
Debt Instrument [Line Items]
Prepayment premium (as a percent)	1.50%		1.50%
Prior to second anniversary and after first anniversary of borrowing date
Debt Instrument [Line Items]
Prepayment premium (as a percent)	1.00%		1.00%
Prior To Maturity Date And After Second Anniversary Of Borrowing Date [Member]
Debt Instrument [Line Items]
Prepayment premium (as a percent)	0.50%		0.50%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable Interest Rate	one-month LIBOR
Basis spread (as a percent)	7.05%
Tranche A
Debt Instrument [Line Items]
Maximum borrowings available	20,000,000		20,000,000
Minimum amount of draw upon closing	10,000,000		10,000,000
Minimum amount of draw after closing	5,000,000		5,000,000
Proceeds received on borrowing, net of deferred financing costs		19,700,000
Tranche B
Debt Instrument [Line Items]
Maximum borrowings available	10,000,000		10,000,000
Minimum net proceeds to be received from stock offering, equity raise, or strategic partner arrangement to allow for borrowing	30,000,000		30,000,000
Remaining borrowing capacity		10,000,000

Stockholders_Equity_Details

Stockholders' Equity (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Share-Based Compensation
Stock-based compensation expense	$722,000	$239,000
Employee Stock Purchase Plan
Share-Based Compensation
Shares available for grant	220,588
Percentage of full share price paid in purchase of common stock	85
Maximum amount of annual employee common stock purchases	25,000
Stock-based compensation expense	60,000
2006 and 2014 Stock Option Plans | Stock Options
Share-Based Compensation
Aggregate fair value of options granted	5,000,000
Number of Shares
Outstanding, beginning of the period (in shares)	2,911,146
Granted (in shares)	516,954
Exercised (in shares)	-157,324
Cancelled (in shares)	-46,724
Outstanding, end of the period (in shares)	3,224,052		2,911,146
Exercisable (in shares)	1,543,881
Vested or expected to vest (in shares)	2,827,095
Weighted Average Exercise Price Per Share
Outstanding, beginning of the period (in dollars per share)	$5.30
Granted (in dollars per share)	$18.20
Exercised (in dollars per share)	$2.38
Cancelled (in dollars per share	$7.97
Outstanding, end of the period (in dollars per share)	$7.47		$5.30
Exercisable (in dollars per share)	$2.74
Vested or expected to vest (in dollars per share)	$7.09
Weighted-Average Remaining Contractual Term (in years)
Outstanding, beginning of the period (in years)	8 years 11 days		7 years 10 months 13 days
Outstanding, end of the period (in years)	8 years 11 days		7 years 10 months 13 days
Exercisable (in years)	6 years 6 months 22 days
Vested or expected to vest (in years)	7 years 10 months 21 days
Aggregate Intrinsic Value
Outstanding, beginning of the period	40,586,000
Exercised	2,067,000
Outstanding, end of the period	25,954,000		40,586,000
Exercisable	19,733,000
Vested or expected to vest	23,822,000
Fair value assumptions
Weighted average fair value of options granted (in dollars per share)	$9.75	$5.73
Weighted-average risk-free interest rate	1.70%	2.04%
Expected dividend yield	0.00%	0.00%
Expected volatility	56.00%	62.00%
Expected terms	6 years 1 month 6 days	6 years 1 month 6 days
Fair value of stock options vested	$499,000	$137,000
2014 Stock Option Plan | Stock Options
Share-Based Compensation
Common stock were reserved for issuance	823,529
Shares available for grant	878,282
Percentage of common shares outstanding	4.00%
2014 Stock Option Plan | Maximum | Stock Options
Share-Based Compensation
Expiration Period	10 years
Vesting period	4 years
2006 Stock Option Plan | Maximum | Stock Options
Share-Based Compensation
Expiration Period	10 years
Vesting period	4 years

Stockholders_Equity_Details_2

Stockholders' Equity (Details 2) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Stock-based compensation expense
Stock-based compensation expense	$722,000	$239,000
Total unrecognized compensation costs related to non-vested stock options	11,480,000
Remaining weighted-average period that unrecognized compensation costs are expected to be recognized	3 years 4 months 24 days
Research and development
Stock-based compensation expense
Stock-based compensation expense	280,000	56,000
Selling, general and administrative
Stock-based compensation expense
Stock-based compensation expense	$442,000	$183,000

Net_Loss_Per_Share_Details_10Q

Net Loss Per Share (Details) - 10Q	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Anti-dilutive securities
Anti-dilutive securities excluded from the computation of diluted net loss per share (in shares)	3,224,052	14,946,373
Redeemable Convertible Preferred Stock [Member]
Anti-dilutive securities
Anti-dilutive securities excluded from the computation of diluted net loss per share (in shares)		12,516,298
Stock Options
Anti-dilutive securities
Anti-dilutive securities excluded from the computation of diluted net loss per share (in shares)	3,224,052	2,282,591
Warrants to purchase redeemable convertible preferred stock
Anti-dilutive securities
Anti-dilutive securities excluded from the computation of diluted net loss per share (in shares)		147,484

Commitments_and_Contingencies_

Commitments and Contingencies (Details) - 10Q (Operating lease entered into August 2010, USD $)	0 Months Ended
	Mar. 31, 2015
Office and laboratory space | Forecast
Operating Leased Assets [Line Items]
Term of lease	2 years
Office Space
Operating Leased Assets [Line Items]
Annual rent owed in 2017	300,000

CoDevelopment_Agreement_with_C1

Co-Development Agreement with Canon US Life Sciences (Details) (USD $)	3 Months Ended	0 Months Ended
	Mar. 31, 2015	Feb. 03, 2015
		item
Co-Development Agreement with Canon US Life Sciences
Revenues	$188,000
Co Development Partnership Agreement | Canon U.S. Life Sciences Inc Member
Co-Development Agreement with Canon US Life Sciences
Upfront payment received		2,000,000
Additional consideration receivable upon achievement of certain development and regulatory milestones		6,500,000
Additional consideration receivable upon achievement of specified technical requirement		1,500,000
Aggregate consideration receivable		8,500,000
Number of units		1
Revenues		$53,000