T2 Biosystems (TTOO) 10-K 31 Mar 21 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Mar. 26, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Trading Symbol	TTOO
Entity Registrant Name	T2 Biosystems, Inc.
Entity Central Index Key	0001492674
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-36571
Entity Tax Identification Number	20-4827488
Entity Address, Address Line One	101 Hartwell Avenue
Entity Address, City or Town	Lexington
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02421
City Area Code	781
Local Phone Number	761-4646
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, par value $0.001
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Annual Report	true
Document Transition Report	false
Entity Common Stock, Shares Outstanding		148,491,673
Entity Public Float			$ 147.9
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
ICFR Auditor Attestation Flag	false
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE None.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 16,793	$ 11,033
Marketable securities	25,396
Accounts receivable	5,099	2,825
Inventories	3,636	3,599
Prepaid expenses and other current assets	2,660	1,438
Total current assets	53,584	18,895
Property and equipment, net	3,771	5,845
Operating lease right-of-use assets	11,034	3,360
Restricted cash	551	180
Marketable securities	10,002
Other assets	136	206
Total assets	79,078	28,486
Current liabilities:
Notes payable		42,902
Accounts payable	2,058	3,753
Accrued expenses and other current liabilities	7,512	11,207
Derivative liability		2,425
Deferred revenue	230	285
Total current liabilities	9,800	60,572
Notes payable, net of current portion	45,235
Operating lease liabilities, net of current portion	10,533	1,873
Deferred revenue, net of current portion	424	46
Derivative liability	1,010
Other liabilities	3,350
Commitments and contingencies (see Note 13)
Stockholders’ equity (deficit):
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 shares authorized; 148,078,974 and 50,651,535 shares issued and outstanding at December 31, 2020 and December 31, 2019, respectively	148	51
Additional paid-in capital	431,544	342,121
Accumulated other comprehensive income	9
Accumulated deficit	(422,975)	(376,177)
Total stockholders’ equity (deficit)	8,726	(34,005)
Total liabilities and stockholders’ equity (deficit)	$ 79,078	$ 28,486

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	148,078,974	50,651,535
Common stock, shares outstanding	148,078,974	50,651,535

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Total revenue	$ 18,130	$ 8,335
Costs and expenses:
Research and development	16,919	16,326
Selling, general and administrative	21,287	27,304
Total costs and expenses	59,486	60,393
Loss from operations	(41,356)	(52,058)
Other income (expense):
Interest income	14	1
Interest expense	(5,518)	(7,349)
Other income, net	62	400
Total other expense	(5,442)	(6,948)
Net loss	$ (46,798)	$ (59,006)
Net loss per share — basic and diluted	$ (0.39)	$ (1.30)
Weighted-average number of common shares used in computing net loss per share — basic and diluted	121,331,464	45,507,754
Other comprehensive loss:
Net loss	$ (46,798)	$ (59,006)
Change in net unrealized gain on marketable securities, net of taxes:
Net unrealized gain on marketable securities arising during the period	13
Less: net realized gain on marketable securities included in net loss	(4)
Net unrealized gain on marketable securities	9
Comprehensive loss	(46,789)	(59,006)
Product [Member]
Revenue:
Total revenue	11,677	5,327
Costs and expenses:
Cost of product revenue	21,280	16,763
Research [Member]
Revenue:
Total revenue	11	563
Contribution [Member]
Revenue:
Total revenue	$ 6,442	$ 2,445

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock [Member]	Common Stock [Member]Purchase Agreement [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]
Balance at Dec. 31, 2018	$ 11,387	$ 44		$ 328,514	$ (317,171)
Balance (in shares) at Dec. 31, 2018		44,175,441
Stock-based compensation expense	5,458			5,458
Issuance of common stock from vesting of restricted stock, exercise of stock options and employee stock purchase plan	582	$ 1		581
Issuance of common stock from vesting of restricted stock, exercise of stock options and employee stock purchase plan (in shares)		576,245
Issuance of common stock	6,650	$ 6		6,644
Issuance of common stock (in shares)		5,486,500	413,349
Change in fair value of warrants upon modification	264			264
Issuance of warrants	660			660
Net loss	(59,006)				(59,006)
Balance at Dec. 31, 2019	$ (34,005)	$ 51		342,121	(376,177)
Balance (in shares) at Dec. 31, 2019	50,651,535	50,651,535
Stock-based compensation expense	$ 3,913			3,913
Issuance of common stock from vesting of restricted stock, exercise of stock options and employee stock purchase plan	296			296
Issuance of common stock from vesting of restricted stock, exercise of stock options and employee stock purchase plan (in shares)		907,272
Issuance of common stock	85,311	$ 97		85,214
Issuance of common stock (in shares)		96,520,167
Unrealized gain on marketable securities	9					$ 9
Net loss	(46,798)				(46,798)
Balance at Dec. 31, 2020	$ 8,726	$ 148		$ 431,544	$ (422,975)	$ 9
Balance (in shares) at Dec. 31, 2020	148,078,974	148,078,974

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Deficit) (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Common Stock [Member]
Issuance costs	$ 3,000	$ 175

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net loss	$ (46,798)	$ (59,006)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,710	2,197
Amortization of bond premium	72
Amortization of operating lease right-of-use assets	1,446	1,445
Stock-based compensation expense	3,913	5,458
Change in fair value of derivative instrument	(1,415)	283
Gain on disposal of property and equipment	(2)	(3)
Impairment of operating lease asset	523	0
Impairment of property and equipment	636	0
Non-cash interest expense	3,238	2,407
Changes in operating assets and liabilities:
Accounts receivable	(2,274)	(1,039)
Prepaid expenses and other assets	(1,152)	(98)
Inventories	441	(914)
Accounts payable	(1,652)	2,960
Accrued expenses and other liabilities	439	3,708
Deferred revenue	323	(499)
Operating lease liabilities	(2,663)	(2,260)
Net cash used in operating activities	(43,215)	(45,361)
Cash flows from investing activities
Purchases of marketable securities	(50,711)
Proceeds from maturities of marketable securities	15,250
Proceeds from sale of property and equipment	4
Purchases and manufacture of property and equipment	(804)	(761)
Net cash used in investing activities	(36,261)	(761)
Cash flow from financing activities
Proceeds from issuance of common stock in public offering, net of offering costs	85,311	6,650
Proceeds from issuance of shares from employee stock purchase plan and stock option exercises	296	582
Principal repayments of finance leases		(882)
Net cash provided by financing activities	85,607	6,350
Net increase (decrease) in cash, cash equivalents and restricted cash	6,131	(39,772)
Cash, cash equivalents and restricted cash at beginning of period	11,213	50,985
Cash, cash equivalents and restricted cash at end of period	17,344	11,213
Reconciliation of cash, cash equivalents and restricted cash at end of period
Cash and cash equivalents	16,793	11,033
Restricted cash	551	180
Cash, cash equivalents and restricted cash at end of period	17,344	11,213
Supplemental disclosures of cash flow information
Cash paid for interest	3,692	4,659
Supplemental disclosures of noncash activities
Transfer of T2 owned instruments and components to (from) inventory	478	(8)
Right-of-use assets obtained in exchange for new operating lease liabilities	9,602	4,805
Change in fair value of warrants issued and modified		924
Purchases of property and equipment included in accounts payable and accrued expenses	$ 41	$ 107

Nature of Business

Nature of Business	12 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of Business	1. Nature of Business T2 Biosystems, Inc. and subsidiary (the “Company,” “we,” or “T2”) have operations based in Lexington, Massachusetts; T2 Biosystems, Inc. was incorporated on April 27, 2006 as a Delaware corporation. The Company is an in vitro ® ® ® TM On June 30, 2020, the Company announced the U.S. launch of its COVID-19 molecular diagnostic test, the T2SARS-CoV-2 Panel, after validation of the test meeting the FDA’s requirements for an Emergency Use Authorization (EUA). In August 2020, the FDA issued EUA for the Company’s T2SARS-CoV-2 Panel. 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 the commercialization and improvement of its existing products. Liquidity and Going Concern At December 31, 2020, the Company has cash, cash equivalents, marketable securities and restricted cash of $52.7 million, an accumulated deficit of $423.0 million and has experienced cash outflows from operating activities over the past years. The future success of the Company is dependent on its ability to successfully commercialize its products, obtain regulatory clearance for and successfully launch its future product candidates, obtain additional capital and ultimately attain profitable operations. Historically, the Company has funded its operations primarily through its August 2014 initial public offering, its December 2015 public offering, its September 2016 private investment in public equity (“PIPE”) financing, its September 2017 public offering, its June 2018 public offering, its July 2019 establishment of an Equity Distribution Agreement and Equity Purchase Agreement (Note 7), private placements of redeemable convertible preferred stock and through debt financing arrangements. The Company is subject to a number of risks similar to other early commercial stage 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 . The COVID-19 pandemic has impacted and may continue to impact operations. The Company has established protocols for continued manufacturing, distribution and servicing of its products with safe social distancing and personal protective equipment measures and for remote work for certain employees not essential to on-site operations. To date these measures have been mostly successful but may not continue to function should the pandemic escalate and impact personnel. The Company’s hospital customers have restricted the sales team’s access to their facilities and as a result, the Company had significantly reduced its sales and general and administrative staffing levels to reduce expenses. Although the Company did not see any material impact to accounts receivable during the year ended December 31, 2020, the Company’s exposure may increase if its customers are adversely affected by the COVID-19 pandemic. Customers may reduce their purchases of products, depending on their needs and cash flow, which could negatively impact revenue. The Company has a significant development contract with a United States government agency and should the agency reduce, cancel or not grant additional milestone projects, the Company’s ability to continue its future product development may be impacted. The ability of the Company’s shipping carriers to deliver products to customers may be disrupted. The Company has reviewed its suppliers and quantities of key materials and believes that it has sufficient stocks and alternate sources of critical materials including personal protective equipment should the supply chains become disrupted, although raw materials for the manufacturing of reagents is in high demand, and interruptions in supply are difficult to predict. As further described in Note 5, at the onset of the pandemic, the Company believed the pandemic’s impact on its sales would affect the recoverability of the value of T2-owned instruments and components. The COVID-19 pandemic also caused the Company to reassess its build plan and evaluate its inventories accordingly, which resulted in an additional charge to cost of product revenue for excess inventories. Since FDA authorization was obtained to market the T2Dx, T2Candida, and T2Bacteria, and EUA for T2SARS-CoV-2, the Company has incurred significant commercialization expenses related to product sales, marketing, manufacturing and distribution. The Company may seek to fund its operations through public equity, private equity or debt financings, as well as other sources. However, the Company may be unable to raise additional funds or enter into such other arrangements when needed, on favorable terms, or at all. The Company’s failure to raise capital or enter into such other arrangements if and when needed would have a negative impact on the Company’s business, results of operations, financial condition and the Company’s ability to develop and commercialize T2Dx, T2Candida, T2Bacteria , T2SARS-CoV-2, and other product candidates. Pursuant to the requirements of Accounting Standards Codification (“ASC”) 205-40, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern While the Company believes that its cash, cash equivalents, marketable securities and restricted cash of $52.7 ertain elements of our operating plan cannot be considered probable. Under ASC 205-40, the future receipt of potential funding from our Co-Development partners and other resources cannot be considered probable at this time because none of the plans are entirely within our control. During the year ended December 31, 2020, management implemented a cost improvement strategy which is focused on reducing operating expenses and improving cost of goods sold. The Term Loan Agreement with CRG Servicing LLC (“CRG”) (Note 6) has certain covenants which require the Company to achieve certain annual revenue targets, whereby the Company is required to pay double the amount of any shortfall as an acceleration of principal payments, and maintain a minimum cash balance of $5.0 These conditions raise substantial doubt regarding the Company’s ability to continue as a going concern for a period of one year after the date that the financial statements are issued. Management's plans to alleviate the conditions that raise substantial doubt include raising additional funding, earning payments pursuant to the Company’s Co- Development agreements, delaying certain research projects and capital expenditures and eliminating certain future operating expenses in order to fund operations at reduced levels for the Company to continue as a going concern for a period of 12 months from the date the financial statements are issued. Management has concluded the likelihood that its plan to successfully obtain sufficient funding from one or more of these sources or adequately reduce expenditures, while reasonably possible, is less than probable. Accordingly, the Company has concluded that substantial doubt exists about the Company’s ability to continue as a going concern for a period of at least 12 months from the date of issuance of these consolidated financial statements. The accompanying financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business. The financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of the uncertainties described above. On April 7, 2020, the Company received a letter from The Nasdaq Stock Market LLC (“Nasdaq”) indicating that, for the last thirty consecutive business days, the bid price for the Company’s common stock had closed below the minimum $1.00 per share requirement for continued listing on the Nasdaq Global Market under Nasdaq Listing Rule 5450(a)(1). On June 16, 2020, the Company received a letter from the Nasdaq stating that the Company had regained compliance.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation and Consolidation The Company’s financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). The Company’s 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. Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The Company utilizes certain estimates in the determination of the accounts receivable allowance, the excess and obsolete inventory, the net realizable value of inventory, the fair value of its stock options, as well as restricted stock units that have market conditions, deferred tax valuation allowances, revenue recognition, expenses relating to research and development contracts, accrued expenses, the fair value of a derivative liability, the fair value of warrants and classification of the value of instrument raw material and work-in-process inventory between inventory and property and equipment. The Company bases its estimates on historical experience and other market ‑ 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 ‑ Geographic Information The Company sells its products domestically and internationally. International sales to a single country did not exceed 10% of total revenue in any year. Total international sales were approximately $2.0 million or 11% of total revenue in 2020 and $2.8 million or 34% of total revenue in 2019. As of December 31, 2020 and 2019, the Company had outstanding receivables of $0.5 million and $1.2 million, respectively, from customers located outside of the U.S. Off ‑ The Company has no significant off-balance sheet risks, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Cash and cash equivalents are financial instruments that potentially subject the Company to concentrations of credit risk. At December 31, 2020, substantially all of the Company’s cash, cash equivalents and marketable securities were deposited in accounts at two financial institutions, with the majority of marketable securities invested in certificates of deposit and U.S. treasury securities. At December 31, 2019, substantially all of the Company’s cash was deposited in accounts at one financial institution, with a portion invested in money market funds that are invested in short-term U.S. government agency securities. The Company maintains its cash deposits, which at times may exceed the federally insured limits, with a large financial institution and, accordingly, the Company believes such funds are subject to minimal credit risk. The Company derived approximately 36% of its total revenue from one customer for the year ended December 31, 2020 and 19% of its total revenue from the same customer for the year ended December 31, 2019. For the year ended December 31, 2020, the Company derived approximately 11% of its total revenue from a second customer and 6% of its total revenue from a third customer. For the year ended December 31, 2019, the Company derived approximately 11% of its total revenue from a second customer and 8% of its total revenue from a third customer. At December 31, 2020, the Company had two customers that represented 20% and 17%, respectively, of its accounts receivable balance. At December 31, 2019, the Company had two customers that represented 27% and 10%, respectively, of its accounts receivable balance. The Company relies on single-source suppliers for some components and materials used in its products and product candidates. The Company has entered into supply agreements with most of its suppliers to help ensure component availability and flexible purchasing terms with respect to th e purchase of such components. While the Company believes replacement suppliers exist for all components and materials obtained from single sources, establishing additional or replacement suppliers for any of these components or materials, if required, may not be accomplished quickly. Even if the Company is able to find a replacement supplier, the replacement supplier would need to be qualified and may require additional regulatory authority approval, which could result in further delay. If third-party suppliers fail to deliver the required commercial quantities of materials on a timely basis and at commercially reasonable prices, and the Company is unable to find one or more replacement suppliers capable of production at a substantially equivalent cost in substantially equivalent volumes and quality on a timely basis, the continued commercialization of products, the supply of products to customers and the development of any future products would be delayed, limited or prevented, which could have an adverse impact on the business. Cash Equivalents Cash equivalents include all highly liquid investments with original maturities of 90 days or less. Cash equivalents consist of certificates of deposit and government securities as of December 31, 2020 and money market funds invested in short-term U.S. government agency securities as of December 31, 2019. Marketable Securities The Company’s marketable securities typically consist of certificates of deposit and U.S. treasury securities, which are classified as available-for-sale and included in current and non-current assets. Available-for-sale debt securities are carried at fair value with unrealized gains and losses reported as a component of stockholders’ equity (deficit) in accumulated other comprehensive income. Realized gains and losses, if any, are included in other income in the consolidated statements of operations. Available-for-sale securities are reviewed for possible impairment at least quarterly, or more frequently if circumstances arise that may indicate impairment. When the fair value of the securities declines below the amortized cost basis, impairment is indicated and it must be determined whether it is other than temporary. Impairment is considered to be other than temporary if the Company: (i) intends to sell the security, (ii) will more likely than not be forced to sell the security before recovering its cost, or (iii) does not expect to recover the security’s amortized cost basis. If the decline in fair value is considered other than temporary, the cost basis of the security is adjusted to its fair market value and the realized loss is reported in earnings. Subsequent increases or decreases in fair value are reported as a component of stockholders’ equity (deficit) in accumulated other comprehensive income. There were no other-than-temporary unrealized losses as of December 31, 2020. The following table summarizes the Company’s marketable securities at December 31, 2020 (in thousands): December 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Certificates of deposit $ 1,250 $ 1 $ — $ 1,251 U.S. treasury securities 34,139 8 — 34,147 Total $ 35,389 $ 9 $ — $ 35,398 The following table summarizes the maturities of the Company’s marketable securities at December 31, 2020 (in thousands): December 31, 2020 Amortized Cost Fair Value Due in less than 1 year $ 25,387 $ 25,396 Due in 1-2 years 10,002 10,002 Total $ 35,389 $ 35,398 Accounts Receivable The Company’s accounts receivable consists of amounts due from product sales to commercial customers and from research and development arrangements with partners. At each reporting period, management reviews historical loss information, characteristics of our customers, our credit practices and the economic conditions, along with all outstanding balances to determine if the facts and circumstances indicate the need for a credit loss allowance. The Company does not require collateral and did not have an allowance for doubtful accounts at December 31, 2020 or 2019. Inventories Inventories are stated at the lower of cost or net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials, direct labor, and manufacturing overhead, on a first-in, first-out basis. The Company performs an assessment of the recoverability of capitalized inventory during each reporting period and records a charge to expense for cost basis in excess of net realizable value in the period in which the impairment is first identified, and writes down any excess and obsolete inventories as appropriate. Shipping and handling costs incurred for inventory purchases are capitalized and recorded upon sale in cost of product revenues in the consolidated statements of operations and comprehensive loss or are included in the value of T2-owned instruments and components, a component of property and equipment, net, and depreciated. The Company capitalizes inventories in preparation for sales of products when the related product candidates are considered to have a high likelihood of regulatory clearance, which for the T2Dx Instrument, T2Candida and T2Bacteria was upon the achievement of regulatory clearance and upon EUA for T2SARS-CoV-2, and the related costs are expected to be recoverable through sales of the inventories. In addition, the Company capitalizes inventories related to the manufacture of instruments that have a high likelihood of regulatory clearance, which for the T2Dx Instrument was upon the achievement of regulatory clearance, and will be retained as the Company’s assets, upon determination that the instrument has alternative future uses. In determining whether or not to capitalize such inventories, the Company evaluates, among other factors, information regarding the product candidate’s status of regulatory submissions and communications with regulatory authorities, the outlook for commercial sales and alternative future uses of the product candidate. Costs associated with development products prior to satisfying the inventory capitalization criteria are charged to research and development expense as incurred. The Company classifies instruments that are T2-owned, as a component of property and equipment. Raw material and work-in-process inventories that are expected to be used to produce T2-owned instruments, based on the Company’s business model and forecast, are also classified as property and equipment. T2-owned instruments are instruments that are manufactured and placed with customers in connection with reagent rental agreements, or are used for internal purposes. The components of inventory consist of the following (in thousands): December 31, December 31, 2020 2019 Raw materials $ 1,496 $ 1,617 Work-in-process 1,374 1,227 Finished goods 766 755 Total inventories, net $ 3,636 $ 3,599 Fair Value Measurements The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC 820, Fair Value Measurements and Disclosures Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability, and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The hierarchy defines three levels of valuation inputs: Level 1 — Quoted unadjusted prices for identical instruments in active markets. Level 2 — Quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model ‑ Level 3 — Model derived valuations in which one or more significant inputs or significant value drivers are unobservable, including assumptions developed by the Company. The fair value hierarchy prioritizes valuation inputs based on the observable nature of those inputs. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability (Note 3). For certain financial instruments, including accounts receivable, prepaid expenses and other current assets, accounts payable and accrued expenses, the carrying amounts approximate their fai r values as of December 31, 20 20 and 201 9 because of their short-t erm nature. At December 31, 20 20 and 201 9 , the fair value of the derivative liability was determined using Level 3 inputs using a valuation model that includes assumptions from the Company (Note 3 ). Property and Equipment Property and equipment are recorded at cost and depreciated over their estimated useful lives using the straight‑line method. Property and equipment, net, includes assets under capital leases. Property and equipment includes raw materials and work-in-process inventory that are expected to be used or used to produce T2-owned instruments based on the Company’s business model and forecast, and finished instruments that will be used for internal research and development, clinical studies or reagent rental agreements with customers. Completed T2-owned instruments are placed in service once installation procedures are completed. Construction in progress is primarily comprised of equipment that has not been placed in service. Leases Pursuant to Topic 842, Leases In accordance with the guidance in ASC 842, components of a lease should be split into three categories: lease components (e.g. land, building, etc.), non-lease components (e.g. common area maintenance, consumables, etc.), and non-components (e.g. property taxes, insurance, etc.). Then the fixed and in-substance fixed contract consideration (including any related to non-components) must be allocated based on the respective relative fair values to the lease components and non-lease components. The Company made the policy election to not separate lease and non-lease components. Each lease component and the related non-lease components are accounted for together as a single component. Revenue Recognition The Company generates revenue from the sale of instruments, consumable diagnostic tests, related services, reagent rental agreements and research and development agreements with third parties. Pursuant to ASC 606, Revenue from Contracts with Customers • Identification of a contract with a customer • Identification of the performance obligations in the contract • Determination of the transaction price • Allocation of the transaction price to the performance obligations • Recognition of revenue as a performance obligation is satisfied. The amount of revenue recognized reflects the consideration the Company expects to be entitled to receive in exchange for these goods and services. Once a contract is determined to be within the scope of ASC 606 at contract inception, the Company reviews the contract to determine which performance obligations the Company must deliver and which of these performance obligations are distinct. The Company recognizes as revenues the amount of the transaction price that is allocated to the respective performance obligation when the performance obligation is satisfied or as it is satisfied. Generally, the Company's performance obligations are transferred to customers at a point in time, typically upon shipment, or over time, as services are performed. Most of the Company’s contracts with distributors in geographic regions outside the United States contain only a single performance obligation, whereas most of the Company’s contracts with direct sales customers in the United States contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative standalone selling price basis. Excluded from the transaction price are sales tax and other similar taxes which are presented on a net basis. Product revenue is generated by the sale of instruments and consumable diagnostic tests predominantly through the Company’s direct sales force in the United States and distributors in geographic regions outside the United States. The Company does not offer product return or exchange rights (other than those relating to defective goods under warranty) or price protection allowances to its customers, including its distributors. Payment terms granted to distributors are the same as those granted to end-user customers and payments are not dependent upon the distributors’ receipt of payment from their end-user customers. The Company either sells instruments to customers and international distributors, or retains title and places the instrument at the customer site pursuant to a reagent rental agreement. When an instrument is purchased by a customer or international distributor, the Company recognizes revenue when the related performance obligation is satisfied (i.e. when the control of an instrument has passed to the customer; typically, at shipping point). When the instrument is placed under a reagent rental agreement, the Company’s customers generally agree to fixed term agreements, which can be extended, and incremental charges on each consumable diagnostic test purchased. Revenue from the sale of consumable diagnostic tests (under a reagent rental agreement) is recognized upon shipment. The transaction price from consumables purchases is allocated between the lease of the instrument (under a contingent rent methodology as provided for in ASC 842, Leases Revenue from the sale of consumable diagnostic tests (under instrument purchase agreements) is recognized upon shipment. Shipping and handling costs billed to customers in connection with a product sale are recorded as a component of the transaction price and allocated to product revenue in the consolidated statements of operations and comprehensive loss as they are incurred by the Company in fulfilling its performance obligations. Direct sales of instruments include warranty, maintenance and technical support services typically for one year following the installation of the purchased instrument (“Maintenance Services”). Maintenance Services are separate performance obligations as they are service based warranties and are recognized on a straight-line basis over the service delivery period. After the completion of the initial Maintenance Services period, customers have the option to renew or extend the Maintenance Services typically for additional Fees paid to member-owned group purchasing organizations (“GPOs”) are deducted from related product revenues. The Company warrants that consumable diagnostic tests will be free from defects, when handled according to product specifications, for the stated life of the product. To fulfill valid warranty claims, the Company provides replacement product free of charge. Accordingly, the Company accrues warranty expense associated with the estimated defect rates of the consumable diagnostic tests. Revenue earned from activities performed pursuant to research and development agreements is reported as research revenue in the consolidated statements of operations and comprehensive loss, and is recognized over time using an input method as the work is completed. 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. Milestones are contingent on the occurrence of future events and are considered variable consideration being constrained until the Company believes a significant revenue reversal will not occur. Refer to Note 15 for further details regarding the Company’s research and development arrangements. Pursuant to ASU No. 2018-08, Not-For-Profit Entities – Clarifying the Scope and the Accounting Guidance for Contributions Received and Contributions Made (“ASU 2018-08”), grants received, including cost reimbursement agreements, are assessed to determine if the agreement should be accounted for as an exchange transaction or a contribution. An agreement is accounted for as a contribution if the resource provider does not receive The Company has a significant development contract with BARDA and should BARDA reduce, cancel or not grant additional milestone projects the Company’s ability to continue our future product development may be impacted. Disaggregation of Revenue The Company disaggregates revenue from contracts with customers by type of products and services, as it best depicts how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors. The following table disaggregates total revenue by major source (in thousands): Year ended December 31, 2020 2019 Product Revenue Instruments $ 3,139 $ 2,280 Consumables 8,423 2,863 Instrument Rentals 115 184 Total Product Revenue 11,677 5,327 Research Revenue 11 563 Contribution Revenue 6,442 2,445 Total Revenue $ 18,130 $ 8,335 Remaining Performance Obligations Remaining performance obligations represent the transaction price of firm orders for which work has not been performed or goods and services have not been delivered. As of December 31, 2020 and 2019, the aggregate amount of transaction price allocated to remaining performance obligations for contracts with an original duration greater than one year was $0.5 million and $0.2 million, respectively. The Company does not disclose the value of unsatisfied performance obligations for (i) contracts with an original expected length of one year or less and (ii) contracts for which it recognizes revenue at the amount to which it has the right to invoice for services performed. The Company expects to recognize revenue on the remaining performance obligations over the next 23 months. Significant Judgments Certain contracts with customers include promises to transfer multiple products and services to a customer. Determining whether products and services are considered distinct performance obligations that should be accounted for separately versus together may require significant judgment. Once the performance obligations are determined, the Company determines the transaction price, which includes estimating the amount of variable consideration, based on the most likely amount, to be included in the transaction price, if any. The Company then allocates the transaction price to each performance obligation in the contract based on a relative stand-alone selling price method. The corresponding revenue is recognized as the related performance obligations are satisfied as discussed in the revenue categories above. Judgment is required to determine the standalone selling price for each distinct performance obligation. The Company determines standalone selling price based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, we estimate the standalone selling price taking into account available information such as a range of selling prices, market conditions and the expected costs and margin related to the performance obligations. Contract Assets and Liabilities The Company did not record any contract assets at December 31, 2020 and 2019. The Company’s contract liabilities consist of upfront payments for research and development contracts and maintenance services on instrument sales. Contract liabilities are classified in deferred revenue as current or noncurrent based on the timing of when revenue is expected to be recognized. At December 31, 2020 and 2019, the Company had contract liabilities of $0.6 million and $0.2 million, respectively. Revenue recognized in the year-ended December 31, 2020 relating to contract liabilities at December 31, 2019 was $0.2 million, and related to straight-line revenue recognition associated with maintenance agreements. Costs to Obtain and Fulfill a Contract The Company capitalizes commission expenses paid to sales personnel that are recoverable and incremental to obtaining capital purchase agreements within the United States. These costs are classified as prepaid expenses and other current assets and other assets, based on their current or non-current nature, respectively. The Company capitalizes only those costs that are determined to be incremental and would not have occurred absent the customer contract. These capitalized costs are amortized as selling, general and administrative costs on a straight line basis over the expected period of benefit. These costs are reviewed periodically for impairment. At December 31, 2020, the Company capitalized costs to fulfill contracts of $0.1 million in prepaid and other current assets and $0.1 million in other non-current assets. At December 31, 2019, no costs to obtain or fulfill contracts were capitalized. Cost of Product Revenue Cost of product revenue includes the cost of materials, direct labor and manufacturing overhead costs used in the manufacture of consumable diagnostic tests sold to customers, related warranty and license and royalty fees. Cost of product revenue also includes depreciation on T2-owned revenue generating T2Dx instruments that have been placed with customers under reagent rental agreements; costs of materials, direct labor and manufacturing overhead costs on the T2Dx instruments sold to customers; and other costs such as customer support costs, royalties and license fees, warranty and repair and maintenance expense on the T2Dx instruments that have been placed with customers under reagent rental agreements. Research and Development Costs Costs incurred in the research and development of the Company’s product candidates are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including activities associated with performing services under research revenue arrangements, costs associated with the enhancements of developed products and include salaries and benefits, stock compensation, research‑related facility and overhead costs, laboratory supplies, equipment and contract services. Impairment of Long-lived Assets The Company reviews long‑lived assets, including capitalized T2 owned instruments and components and capitalized costs to fulfill a contract, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indications of impairment exist, projected future undiscounted cash flows associated with the asset or asset group are compared to the carrying amount to determine whether the asset’s value is recoverable. During this review, the Company reevaluates the significant assumptions used in determining the original cost and estimated lives of long‑lived assets. Although the assumptions may vary from asset to asset, they generally include operating results, changes in the use of the asset, cash flows and other indicators of value. Management then determines whether the remaining useful life continues to be appropriate or whether there has been an impairment of long‑lived assets based primarily upon whether expected future undiscounted cash flows are sufficient to support the assets’ recovery. If impairment exists, the Company would adjust the carrying value of the asset to fair value, generally determined by a discounted cash flow analysis. If the carrying value of the asset exceeds such projected undiscounted cash flows, the asset will be written down to its estimated fair value. The Company recorded an impairment of property and equipment of $0.6 million and an impairment of an operating lease asset of $0.5 million during the year ended December 31, 2020 and did not record any impairment expense during the year ended December 31, 2019. Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non‑owner sources. Comprehensive loss consists of net loss and other comprehensive loss, which includes certain changes in equity that are excluded from net loss. The Company had a net change in available-for-sale securities for the year ended December 31, 2020. The Company’s comprehensive loss equals reported net loss for the year ended December 31, 2019. Stock-Based Compensation The Company issues stock-based awards to employees, generally in the form of stock options, restricted stock units and restricted stock awards. The Company accounts for stock-based awards in accordance with FASB ASC Topic 718, Compensation-Stock Compensation The Company estimates the fair value of the stock-based awards to employees using the Black-Scholes-Merton option pricing model, which requires the input of highly subjective assumptions, including (a) the expected volatility of the stock, (b) the expected term of the award, (c) the risk-free interest rate and (d) expected dividends. The Company estimates expected volatility based on the historical volatility of the stock using the daily closing prices during the equivalent period of the calculated expected term of its stock‑based awards. The Company has estimated the expected life of the employee stock options using the “simplified” method, whereby the expected life equals the average of the vesting term, and the original contractual term of the option. The risk-free interest rates for periods within the expected life of the option are based on the U.S. Treasury yield curve in effect during the period in which the options were granted. The Company has not paid, and does not anticipate paying, cash dividends on shares of common stock; therefore, the expected dividend yield is assumed to be zero. The Company elected an accounting policy to estimate forfeitures at the time of grant and revise those estimates in subsequent periods if actual forfeitures differ from the estimates. Historical data is used to estimate pre-vesting option forfeitures and stock-based compensation expense is only recorded for those awards that are expected to vest. To the extent that actual forfeitures differ from the estimates, the difference is recorded as a cumulative adjustment in the period the estimates were revised. Stock-based compensation expense recognized in the financial statements is based on awards that are ultimately expected to vest. If the actual forfeiture rate is materially different from the estimate, stock-based compensation expense could be different from what we have recorded in the current period. The Company estimate s the fair value of restricted stock units with market conditions on the date of grant using a Monte Carlo simulation. The compensation cost for restricted stock units with market conditions is being recorded over the derived service period. If a market condition is achieved prior to completion of the derived service period, the remaining compensation cost will be recognized immediately. These assumptions used to determine stock compensation expense represent the Company’s best estimates, but the estimates involve inherent uncertainties and the application of judgment. As a result, if factors change and the Company uses significantly different assumptions or estimates, stock-based compensation expense could be materially different. Refer to Note 8 for further details on the Company’s stock-based compensation plan. Income Taxes The Company provides for income taxes using the liability method. The Company provides deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the Company’s financial statement carrying amounts and the tax basis

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The Company measures the following financial assets at fair value on a recurring basis. There were no transfers between levels of the fair value hierarchy during any of the periods presented. The following tables set forth the Company’s financial assets and liabilities carried at fair value categorized using the lowest level of input applicable to each financial instrument as of December 31, 2020 and 2019 (in thousands): Quoted Prices in Active Significant Markets for Other Significant Balance at Identical Observable Unobservable December 31, Assets Inputs Inputs 2020 (Level 1) (Level 2) (Level 3) Assets: Certificates of deposit $ 1,251 $ — $ 1,251 $ — US Treasury securities 34,147 34,147 — — Restricted cash 551 551 — — $ 35,949 $ 34,698 $ 1,251 $ — Liabilities: Derivative liability $ 1,010 $ — $ — $ 1,010 $ 1,010 $ — $ — $ 1,010 Quoted Prices in Active Significant Markets for Other Significant Balance at Identical Observable Unobservable December 31, Assets Inputs Inputs 2019 (Level 1) (Level 2) (Level 3) Assets: Money market funds $ 4,301 $ 4,301 $ — $ — Restricted cash 180 180 — — $ 4,481 $ 4,481 $ — $ — Liabilities: Derivative liability $ 2,425 $ — $ — $ 2,425 $ 2,425 $ — $ — $ 2,425 The Company’s cash equivalents and available-for-sale marketable securities are comprised of certificates of deposit and government securities. Securities are classified as cash equivalents when the original maturities are within 90 days of the purchase dates. The Company also maintains money market accounts classified as restricted cash for $0.6 million at December 31, 2020 and certificates of deposit classified as restricted cash for $0.2 million at December 31, 2019 (Note 4). The Company has a single compound derivative related to its Term Loan Agreement with CRG (the “Term Loan Agreement”) (Note 6), which is required to be re-measured at fair value on a quarterly basis. The fair value of the derivative at December 31, 2020 and December 31, 2019 is $1.0 million and $2.4 million, respectively, and is classified as a non-current liability on the balance sheet at December 31, 2020, and a current liability at December 31, 2019 to match the classification of the related Term Loan Agreement (Note 6). While the Company’s fair value assessment as of December 31, 2020 assessed the likelihood of paying contingent interest as remote within the next twelve months and as of the date of this filing the Company continues to assess and believes the probability is remote that the contingent interest will commence within the next twelve months which, accordingly, provided for the non-current classification of the derivative liability. Management continues to reassess at each balance sheet and filing date based on facts and circumstances and can provide no assurances regarding the probability of payment of the contingent interest in future periods. The estimated fair value of the derivative at December 31, 2020 was determined using a probability-weighted discounted cash flow model that includes contingent interest payments under the following scenarios: Range 4% contingent interest beginning in 2021 0 % 4% contingent interest beginning in 2022 90 % The following table provides a roll-forward of the fair value of the derivative liability (in thousands): Balance at December 31, 2018 $ 2,142 Change in fair value of derivative liability, recorded as interest expense 283 Balance at December 31, 2019 2,425 Change in fair value of derivative liability, recorded as interest expense (1,415 ) Balance at December 31, 2020 $ 1,010

Restricted Cash

Restricted Cash	12 Months Ended
	Dec. 31, 2020
Restricted Cash [Abstract]
Restricted Cash	4. Restricted Cash The Company is required to maintain security deposits for its operating lease agreement for the duration of the lease agreement and for a particular credit card program as long as it is in place. At December 31, 2020, the Company had money market accounts for $0.6 million, which represented collateral as security deposits for its operating lease agreements for two facilities.

Supplemental Balance Sheet Info

Supplemental Balance Sheet Information	12 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Supplemental Balance Sheet Information	5. Supplemental Balance Sheet Information Property and Equipment Property and equipment consists of the following (dollar amounts in thousands) Estimated Useful December 31, December 31, Life (Years) 2020 2019 Office and computer equipment 3 $ 538 $ 538 Software 3 762 762 Laboratory equipment 5 5,179 4,747 Furniture 5-7 197 194 Manufacturing equipment 5 672 672 Manufacturing tooling and molds 0.5-5 255 255 T2-owned instruments and components 5 5,001 6,775 Leasehold improvements Lesser of useful life or remaining lease term 3,691 3,497 Construction in progress n/a 1,733 1,641 18,028 19,081 Less accumulated depreciation and amortization (14,257 ) (13,236 ) Property and equipment, net $ 3,771 $ 5,845 Construction in progress is primarily comprised of equipment that has not been placed in service. T2-owned instruments and components is comprised of raw materials and work-in-process inventory that are expected to be used or used to produce T2-owned instruments, based on the Company’s business model and forecast, and completed instruments that will be used for internal research and development, clinical studies or reagent rental agreements with customers. At December 31, 2020, there were $0.3 million of raw materials and work-in-process inventory in T2-owned instruments and components compared to $0.6 million at December 31, 2019. Completed T2-owned instruments are placed in service once installation procedures are completed and are depreciated over five years. Depreciation expense for T2-owned instruments placed at customer sites pursuant to reagent rental agreements is recorded as a component of cost of product revenue and totaled $0.3 million and $0.8 million for the year ended December 31, 2020 and 2019, respectively. Depreciation expense for T2-owned instruments used for internal research and development and clinical studies is recorded as a component of research and development expense. Depreciation and amortization expense of $1.7 million and $2.2 million was charged to operations for the years ended December 31, 2020 and 2019, respectively. At the beginning of the COVID-19 pandemic, the Company believed the pandemic would reduce product sales and impair the ability to recover the cost of the T2-owned instruments and components. The Company assessed the impact on the related cash flows of the T2-owned instruments and reduced the respective carrying values by $0.6 million as of December 31, 2020, which is recorded as cost of product revenue impairment expense. Accrued Expenses Accrued expenses consist of the following (in thousands): December 31, December 31, 2020 2019 Accrued payroll and compensation $ 3,629 $ 3,193 Accrued final fee — 2,445 Accrued research and development expenses 751 267 Accrued professional services 421 511 Accrued interest 940 908 Operating lease liabilities 1,151 1,983 Other accrued expenses 620 1,900 Total accrued expenses and other current liabilities $ 7,512 $ 11,207 At December 31, 2019, a fee associated with the Company’s Term Loan Agreement (Note 6) of $2.4 million is included as accrued final fee in the table above to match the current classification of the associated debt. At December 31, 2020, the Company’s Term Loan Agreement with CRG and the associated fee of $3.4 million are classified as non-current liabilities. At December 31, 2020, included within other accrued expenses in the table above is $0.2 million related to Mr. McDonough’s transition payments and health benefits. Included within other accrued expenses and accrued payroll and compensation in the table above, at December 31, 2019, are $1.0 million and $0.2 million, respectively, related to the Transition Agreement (Note 13).

Notes Payable

Notes Payable	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Notes Payable	6. Notes Payable Future principal payments on the notes payable as of December 31, 2020 are as follows (in thousands): Year ended December 31, 2021 $ — 2022 48,077 2023 — 2024 — 2025 — Total before unamortized discount and issuance costs 48,077 Less: paid-in-kind interest (1,669 ) Less: unamortized discount and issuance costs (1,173 ) Total notes payable $ 45,235 The Term Loan Agreement with CRG is classified as a non-current liability at December 31, 2020 as the Company has sufficient cash, cash equivalents and marketable securities as of the date of this filing that the minimum liquidity covenant would not be triggered even upon default of the revenue covenant at December 31 2020, as the cure would not be due until March 31, 2022. The Term Loan Agreement with CRG is classified as a current liability on the balance sheet at December 31, 2019, based on the Company’s consideration of the probability of violating the 2020 revenue covenant, which in turn would trigger violation of the minimum liquidity covenant included in the Term Loan Agreement. The Term Loan Agreement includes a subjective acceleration clause whereby an event of default, including a material adverse change in the business, operations, or conditions (financial or otherwise), could result in the acceleration of the obligations under the Term Loan Agreement. The contractual terms of the agreement, as amended in September 2019, require quarterly principal payments of $12.0 million commencing March 31, 2022 through maturity, December 31, 2022, respectively. The January 2021 amendment extends the principal repayment to be due upon maturity, December 31, 2022. The Company has assessed the classification of the note payable as non-current based on facts and circumstances as of the date of this filing, specifically as it relates to achieving the minimum liquidity and revenue covenants. As of the date of this filing, the Company believes that should it be unable to meet such covenants as of December 31, 2020, it is probable that it would be able to pay the cure of default on March 31, 2022. Management continues to reassess at each balance sheet and filing date based on facts and circumstances and can provide no assurances regarding the probability of meeting its aforementioned covenants in future periods. Term Loan Agreement In December 2016, the Company entered into a Term Loan Agreement (the “Term Loan Agreement”) with CRG. The Company borrowed $40.0 million pursuant to the Term Loan Agreement, which has a six-year The Company may prepay all or a portion of the outstanding principal and accrued unpaid interest under the Term Loan Agreement at any time upon prior notice subject to a certain prepayment fee during the first five years of the term and no prepayment fee thereafter. As security for its obligations under the Term Loan Agreement the Company entered into a security agreement with CRG whereby the Company granted a lien on substantially all of its assets, including intellectual property. The Term Loan Agreement also contains customary affirmative and negative covenants for a credit facility of this size and type, including a requirement to maintain a minimum cash balance. The Term Loan Agreement also requires the Company to achieve certain revenue targets, whereby the Company is required to pay double the amount of any shortfall as an acceleration of principal payments. In March 2019, the Term Loan Agreement was amended to reduce the 2019 minimum revenue target to $9.0 million and eliminate the 2018 revenue covenant. In exchange for the amendment, the Company agreed to reset the strike price of the warrants to purchase 528,958 shares of the Company’s common stock, issued in connection with the Term Loan Agreement, from $8.06 per share to $4.35 per share (Note 9). In September 2019, the Term Loan Agreement was amended to extend the interest-only payment period through December 31, 2021, to extend the initial principal repayment to March 31, 2022, and to reduce the minimum product revenue target for 2019 from $9 million to $4 million, for the twenty-four month period beginning on January 1, 2019 from $95 million to $15 million and for the twenty-four month period beginning on January 1, 2020 from $140 million to $43 million. In January 2021, the Term Loan Agreement was amended to extend the interest-only payment period until the December 30, 2022 maturity, to extend the initial principal repayment until the December 30, 2022 maturity, and to significantly reduce the minimum product revenue target for the twenty-four month period beginning on January 1, 2020. The Company did not pay or provide any consideration in exchange for this amendment. The Term Loan Agreement includes a subjective acceleration clause whereby an event of default, including a material adverse change in the business, operations, or conditions (financial or otherwise), could result in the acceleration of the obligations under the Term Loan Agreement. Under certain circumstances, a default interest rate of an additional 4.0% per annum will apply at the election of CRG on all outstanding obligations during the occurrence and continuance of an event of default. Equipment Lease Credit Facility In October 2015, the Company signed the $10.0 million Credit Facility (the “Credit Facility”) with Essex Capital Corporation (“Essex”) to fund capital equipment needs. As one of the conditions of the Term Loan Agreement, the Credit Facility is capped at a maximum of $5.0 million. Under the Credit Facility, Essex will fund capital equipment purchases presented by the Company. The Company will repay the amounts borrowed in 36 equal monthly installments from the date of the amount funded. At the end of the 36-month lease term, the Company has the option to (a) repurchase the leased equipment at the lesser of fair market value or 10% of the original equipment value, (b) extend the applicable lease for a specified period of time, which will not be less than one year, or (c) return the leased equipment to the Lessor. In April 2016 and June 2016, the Company completed the first two draws under the Credit Facility of $2.1 million and $2.5 million, respectively. The Company made monthly payments of $67,000 under the first draw and $79,000 under the second draw. The borrowings under the Credit Facility were treated as capital leases and were included in property and equipment on the balance sheet. The amortization of the assets conveyed under the Credit Facility was included as a component of depreciation expense. During the year ended December 31, 2019, the Company repurchased the equipment for $0.3 million in accordance with the terms of the Credit Facility.

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Stockholders' Equity (Deficit)	7. Stockholders’ Equity (Deficit) Common Stock Each share of common stock is entitled to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the Board of Directors, subject to the prior rights of holders of all classes of stock outstanding. The Company authorized 200,000,000 shares of common stock, $0.001 par value per share, of which 148,078,974 and 50,651,535 were outstanding as of December 31, 2020 and 2019, respectively. As of December 31, 2020, a total of 8,595,929 shares, 1,643,779 shares, and 1,097,249 shares of common stock were reserved for issuance upon (i) the exercise of outstanding stock options, (ii) the issuance of stock awards, and (iii) the exercise of warrants, respectively, under the Company’s 2014 Incentive Award Plan, Inducement Award Plan, and 2014 Employee Stock Purchase Plan. Equity Distribution Agreement On July 30, 2019, the Company entered into the Sales Agreement with Canaccord, as agent, pursuant to which the Company may offer and sell shares of common stock, for aggregate gross sale proceeds of up to $30.0 million from time to time through Canaccord. On March 9, 2020, the Company entered into an amendment to the Sales Agreement to increase the aggregate gross sales amount from $30.0 million to $65.0 million. On April 8, 2020, the Company entered into an amendment to the Sales Agreement to increase the aggregate gross sales amount from $65.0 million to $95.0 million. As of December 31, 2020, the Company had sold 101,606,667 shares of common stock with an aggregate gross sales amount of $95.0 million. Upon delivery of a placement notice based on the Company’s instructions and subject to the terms and conditions of the Sales Agreement, Canaccord was able to sell the shares by methods deemed to be an “at the market” offering, subject to shelf limitations if any, in negotiated transactions at market prices prevailing at the time of sale or at prices related to such prevailing market prices, or by any other method permitted by law, including negotiated transactions, subject to the prior written consent of the Company. The Company was not obligated to make any sales of shares under the Sales Agreement. The Company or Canaccord were able to suspend or terminate the offering of shares upon notice to the other party, subject to certain conditions. Canaccord acted as sales agent on a commercially reasonable efforts basis consistent with its normal trading and sales practices and applicable state and federal law, rules and regulations and the rules of Nasdaq. The Company had agreed to pay Canaccord for its services of acting as agent 3% of the gross proceeds from the sale of the shares pursuant to the Sales Agreement. The Company had also agreed to provide Canaccord with customary indemnification for certain liabilities. Legal and accounting fees associated with the Sales Agreement were immaterial. Legal and accounting fees were changed to share capital upon issuance of shares under the Sales Agreement. During the year ended December 31, 2020, the Company sold 96,120,167 shares under the Sales Agreement for net proceeds of $85.0 million after expenses. During the year ended December 31, 2019, the Company sold 5,486,500 shares for net proceeds of $6.7 million after expenses in connection with the Sales Agreement. Purchase Agreement On July 29, 2019, the Company entered into a $30.0 million Purchase Agreement with Lincoln Park, pursuant to which the Company may sell and issue to Lincoln Park, and Lincoln Park is obligated to purchase, up to $30.0 million in value of its shares of common stock from time to time over a 36-month period starting from the effective date of the respective registration statement. On April 7, 2020, the Company terminated the Purchase Agreement, effective April 8, 2020. The Company was able to direct Lincoln Park, at its sole discretion, and subject to certain conditions, to purchase up to 200,000 shares of common stock on any business day, provided that at least one business day had passed since the most recent purchase. The amount of a purchase could be increased under certain circumstances provided, however, that Lincoln Park’s committed obligation under any single purchase would not exceed $2.0 million. The purchase price of shares of common stock related to the future funding was based on the then prevailing market prices of such shares at the time of sales as described in the Purchase Agreement . In consideration for the execution and delivery of the Purchase Agreement, the Company issued 413,349 shares of common stock to Lincoln Park. During the year ended December 31, 2020, the Company sold 400,000 shares for proceeds of $0.3 million in connection with the Purchase Agreement.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	8. Stock-Based Compensation Stock Incentive Plans 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 Incentive Award Plan (“2014 Plan”, and together with the 2006 Plan, the “Stock Incentive 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 primarily granted stock options and restricted stock units. 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, (2) any shares that were granted under the 2006 Plan which are forfeited, lapse 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, 2026, equal to the lesser of (A) 4% of the shares outstanding on the final day of the immediately preceding calendar year and (B) such smaller number of shares determined by the Board of Directors. As of December 31, 2020, there were 2,237,168 shares available for future grant under the Stock Incentive Plans. Inducement Award Plan The Company’s Amended and Restated Inducement Award Plan (“Inducement Plan”), which was adopted in March 2018 and most recently amended and restated in January 2020, provides for the granting of equity awards to new employees, including options, restricted stock awards, restricted stock units, performance awards, dividend equivalent awards, stock payment awards and stock appreciation rights. The aggregate number of shares of common stock which may be issued or transferred pursuant to awards under the Inducement Plan is 5,625,000 shares. As of December 31, 2020, there were 2,073,281 shares available for future grant under the Inducement Plan. Stock Options During the years ended December 31, 2020 and 2019, the Company granted options with an aggregate fair value of $3.3 million and $3.9 million, respectively, 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 Stock Incentive Plans and Inducement Plan (in thousands, except term, share and per share amounts): Weighted-Average Weighted-Average Remaining Number of Exercise Price Per Contractual Term Aggregate Intrinsic Shares Share (In years) Value Outstanding at December 31, 2019 6,353,330 $ 4.95 7.29 $ 229 Granted 4,306,750 1.02 Exercised (49,563 ) 0.61 33 Forfeited (1,232,700 ) 3.04 Canceled (781,888 ) 5.43 Outstanding at December 31, 2020 8,595,929 3.24 7.75 1,011 Exercisable at December 31, 2020 4,098,314 4.98 6.57 272 Vested or expected to vest at December 31, 2020 7,650,363 $ 3.46 7.61 $ 845 There were 49,563 options exercised in the year ended December 31, 2020 and 2,119 options exercised in the year ended December 31, 2019. The total intrinsic value of options exercised in the years ended December 31, 2020 and 2019 were immaterial. The weighted‑average fair values of options granted in the years ended December 31, 2020 and 2019 were $0.71 and $1.41 per share, respectively, and were calculated using the following estimated assumptions: Year ended December 31, 2020 2019 Weighted-average risk-free interest rate 1.35 % 1.97 % Expected dividend yield 0.00 % 0.00 % Expected volatility 92 % 78 % Expected terms 5.8 years 6.0 years The total fair values of stock options that vested during the years ended December 31, 2020 and 2019 were $3.5 million and $3.1 million, respectively. As of December 31, 2020, there was $4.1 million of total unrecognized compensation cost related to non‑vested stock options granted under the Stock Incentive 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 2.4 years as of December 31, 2020. Restricted Stock Units During the year ended December 31, 2020, the Company awarded shares of restricted stock units to certain employees at no cost to them, which cannot be sold, assigned, transferred or pledged during the restriction period. The restricted stock units vest through the passage of time, assuming continued employment. Restricted stock units are not included in issued and outstanding common stock until the shares are vested and released. During the year ended December 31, 2018, an additional 73,172 restricted stock units vested but are not reflected as outstanding shares at December 31, 2019 due to a deferred release date. These restricted stock units are reflected as outstanding shares at December 31, 2020. The fair value of the restricted stock units, at the time of the grant, is expensed on a straight line basis. The granted restricted stock units had an aggregate fair value of $1.2 million, which are being amortized into compensation expense over the vesting period of the restricted stock units as the services are being provided. Included in the nonvested restricted stock units at December 31, 2020 are 318,898 restricted stock units with market conditions, which vest upon the achievement of stock price targets. The compensation cost for restricted stock units with market conditions is being recorded over the derived service period and was immaterial for the year ended December 31, 2020 and $1.0 million for the year ended December 31, 2019. The following is a summary of restricted stock unit activity under the 2014 Plan: Weighted-Average Number of Grant Date Fair Shares Value Nonvested at December 31, 2019 1,295,508 $ 4.19 Granted 1,380,923 0.89 Vested (331,433 ) 3.45 Forfeited (701,219 ) 3.37 Canceled — — Nonvested at December 31, 2020 1,643,779 $ 1.91 As of December 31, 2020, there was $1.2 million of total unrecognized compensation cost related to non‑vested restricted stock units granted under the 2014 Plan. 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 1.6 years as of December 31, 2020. Employee Stock Purchase Plan The 2014 Employee Stock Purchase Plan (the “2014 ESPP”) 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 calendar year in fair market value. The first plan period began on August 7, 2014. Stock-based compensation expense from the 2014 ESPP for the years ended December 31, 2020 and 2019 was approximately $0.3 million and $0.4 million, respectively. During the year ended December 31, 2020, 453,104 shares were purchased through the 2014 ESPP. The fair value of the purchase rights granted under this plan was estimated on the date of grant and uses the following weighted-average assumptions, which were derived in a manner similar to those discussed in Note 2 relative to stock options: Year ended December 31, 2020 2019 Weighted-average risk-free interest rate 1.59 % 2.44 % Expected dividend yield 0.00 % 0.00 % Expected volatility 92 % 71 % Expected terms 0.5 years 0.5 years The 2014 ESPP, which was amended and restated effective August 6, 2020, provides for the granting of up to 4,523,944 shares of the Company’s common stock to eligible employees. At December 31, 2020, there were 3,268,850 shares available under the 2014 ESPP. Stock‑Based Compensation Expense The following table summarizes the stock-based compensation expense resulting from awards granted under Stock Incentive Plans, the Inducement Plan and 2014 ESPP, that was recorded in the Company’s results of operations for the years presented (in thousands): Year ended December 31, 2020 2019 Cost of product revenue $ 221 $ 365 Research and development 777 1,184 Selling, general and administrative 2,901 3,888 Total stock-based compensation expense $ 3,899 $ 5,437 For the years ended December 31, 2020 and 2019, stock-based compensation expense capitalized as part of inventory or T2-owned instruments and components was immaterial.

Warrants

Warrants	12 Months Ended
	Dec. 31, 2020
Warrants And Rights Note Disclosure [Abstract]
Warrants	9. Warrants In connection with the Term Loan Agreement entered into in December 2016, the Company issued to CRG warrants to purchase a total of 528,958 shares of the Company’s common stock. The warrants are exercisable any time prior to December 30, 2026 at a price of $4.35 per share, which was amended in March 2019 from an original price of $8.06 per share, with typical provisions for termination upon a change of control or a sale of all or substantially all of the assets of the Company. In connection with the September 2019 amendment of the Term Loan Agreement, the Company issued to CRG warrants to purchase 568,291 shares of the Company’s common stock (“New Warrants”) at an exercise price of $1.55, with typical provisions for termination upon a change of control or a sale of all or substantially all of the assets of the Company. The Company also reduced the exercise price for the warrants previously issued to CRG to $1.55. All of the New Warrants are exercisable any time prior to September 9, 2029. The warrants are classified within stockholders’ equity (deficit), and the proceeds were allocated between the debt and the originally issued warrants based on their relative fair value. The fair value of the new and amended warrants was determined by the Black-Scholes-Merton option pricing model. The incremental fair value of the amended warrants of $0.1 million and the fair value of the New Warrants of $0.7 million were recorded as debt discount and additional paid-in-capital.

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Net Loss Per Share	10. Net Loss Per Share The following table presents the calculation of basic and diluted net loss per share applicable to common stockholders (in thousands, except share and per share data): Year ended December 31, 2020 2019 Numerator: Net loss $ (46,798 ) $ (59,006 ) Denominator: Weighted-average number of common shares outstanding — basic and diluted 121,331,464 45,507,754 Net loss per share applicable to common stockholders — basic and diluted $ (0.39 ) $ (1.30 ) 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 their effect would have been anti ‑ Year ended December 31, 2020 2019 Options to purchase common shares 8,595,929 6,353,330 Restricted stock units 1,643,779 1,295,508 Warrants to purchase common stock 1,097,249 1,097,249 Total 11,336,957 8,746,087

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes The reconciliation of the U.S. federal statutory rate to the Company’s effective tax rate is as follows: Year Ended December 31, 2020 2019 Tax at statutory rates 21.0 % 21.0 % State income taxes 6.4 2.6 Permanent differences (1.9 ) (1.2 ) Research and development credits 1.4 1.0 Limitations on credits and net operating losses 0.1 (75.2 ) Change in valuation allowance (27.0 ) 51.8 Effective tax rate 0.0 % 0.0 % The significant components of the Company’s deferred tax asset consist of the following at December 31, 2020 and 2019 (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 61,551 $ 50,407 Tax credits 1,428 472 Other temporary differences 3,546 2,888 Start-up expenditures 2,672 2,716 Stock option expenses 3,382 3,450 Lease liability 3,170 987 Total deferred tax assets 75,749 60,920 Deferred tax asset valuation allowance (72,404 ) (59,764 ) Net deferred tax assets 3,345 1,156 Deferred tax liabilities: Right of use asset (2,994 ) (859 ) Prepaid expenses (351 ) (297 ) Net deferred taxes $ — $ — In 2020 and 2019, the Company did not record a benefit for income taxes related to its operating losses incurred. ASC 740 requires a valuation allowance to reduce the deferred tax assets reported if, based on the weight of available evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. Based upon the level of historical U.S. losses and future projections over the period in which the net deferred tax assets are deductible, at this time, management believes it is more likely than not that the Company will not realize the benefits of these deductible differences, and as a result the Company continues to maintain a valuation allowance for the full amount of the 2020 deferred tax assets. The valuation allowance increased by $12.6 million and decreased $30.6 million for the years ended December 31, 2020 and 2019, respectively. The increase in the 2020 valuation allowance is primarily attributable to the current year loss. The decrease in 2019 was primarily attributable to the reduction of the net operating loss and tax credit carryforwards recorded as a result of the completion of the Section 382 study performed. As of December 31, 2020, the Company had federal and state net operating losses of $222.6 million and $247.9 million, respectively, which are available to offset future taxable income, if any, of which $78.7 million of federal and $215.3 million of state carryforwards will expire in varying amounts through 2037 and 2040, respectively. Additionally, $143.9 million of federal net operating loss carryforwards and $32.6 million of state net operating loss carryforwards will carryforward indefinitely, subject to annual taxable income limitations in the year of utilization. The Company also had federal and state research and development tax credits of $0.8 million and $0.8 million, respectively, which expire at various dates through 2040 for federal purposes and 2035 for state purposes. Under the provisions of the Internal Revenue Code, the net operating loss and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities. Net operating loss and tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant stockholders over a three-year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions. In 2020, the Company completed a study on its historic ownership changes pursuant to Internal Revenue Code Section 382 and 383 (the “382 study”) of its historical net operating loss and tax credit carryforwards. As a result, there were limitations placed on the use of the Company’s loss and credit carryforwards. The 2019 federal and state net operating loss carryforwards of $329.6 million and $292.4 million, respectively, were determined to be limited by $149.5 million and $78.9 million, respectively. The 2019 federal and state tax credit carryforwards of $5.5 million and $3.6 million, respectively, were limited by $5.4 million and $3.2 million, respectively. The decrease in the prior year tax attributes is attributable to change of control ownership shifts which were determined for the years 2013, 2016, and 2019 which caused the reduction in the value of the historical net operating loss carryforwards. Since the limitation affected the prior period, the Company has determined that its 2019 tax footnote presentation overstated the gross net operating loss deferred tax asset and corresponding valuation allowance. However, there was no net impact to the net deferred tax asset and tax expense as the decrease in the net operating loss carryforward was offset completely by a corresponding adjustment to the Company’s overall valuation allowance. For comparative purposes, the Company’s prior year tax footnote has been revised to reflect the adjustment to the net operating losses and valuation allowance. Subsequent ownership changes may further affect the limitation in future years. The Company has no unrecognized tax benefits. Interest and penalty charges, if any, related to uncertain tax positions would be classified as income tax expenses in the accompanying consolidated statements of operations. At December 31, 2020 and 2019, the Company had no accrued interest or penalties related to uncertain tax positions. The Company files income tax returns in the U.S. federal tax jurisdiction and various state jurisdictions. Since the Company is in a loss carryforward position, the Company is generally subject to examination by the U.S. federal, state and local income tax authorities for all tax years in which a loss carryforward is available. The Company does not have any international operations as of December 31, 2020. The statute of limitations for assessment by federal and state tax jurisdictions in which the Company has business operations is open for tax years ending December 31, 2017 and after. The tax years under examination vary by jurisdiction.

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	12. Leases Operating Leases The Company leases certain office space, laboratory space, and equipment. At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease based on the unique facts and circumstances present. The Company does not recognize right-of-use assets or lease liabilities for leases determined to have a term of 12 months or less. For new and amended leases beginning in 2019 and after, the Company has elected to account for the lease and non-lease components as a combined lease component. In August 2010, the Company entered into an operating lease for office and laboratory space at its headquarters in Lexington, Massachusetts. The lease commenced in January 2011, with the Company providing a security deposit of $400,000. In accordance with the operating lease agreement, the Company reduced its security deposit to $180,000 in January 2018, which is recorded as restricted cash in the consolidated balance sheets. In March 2017, the Company entered into an amendment to extend the term to December 2021. In October 2020, the Company entered into an amendment to extend the term to December 31, 2028. In accordance with the October 2020 amendment, the Company increased its security deposit to $420,438, which is classified as restricted cash at December 31, 2020. This amendment resulted in an increase to the operating lease right-of use assets and lease liability accounts on the balance sheet of $7.6 million and $7.7 million, respectively, at December 31, 2020. In May 2013, the Company entered into an operating lease for additional office, laboratory and manufacturing space in Wilmington, Massachusetts. In August 2018, the Company entered into an amendment to extend the term to December 2020. In October 2020, the Company entered into an amendment to extend the term to December 31, 2022. This amendment resulted in an increase to the operating lease right-of use assets and lease liability accounts on the balance sheet of $0.2 million at December 31, 2020. In November 2014, the Company entered into an agreement to rent additional office space in Lexington, Massachusetts. In April 2015, the Company entered into an amendment to extend the term to December 31, 2017. In connection with this agreement, the Company paid a security deposit of $50,000, which is recorded as a component of other assets in the consolidated balance sheets. In May 2015, the Company entered into an amendment to expand existing manufacturing facilities in Lexington, Massachusetts. In September 2017, the Company entered into an amendment to extend the term to December 31, 2021. In June 2020, the Company vacated this office space and determined that subleasing it to a tenant was unlikely due to the impact of the COVID-19 pandemic on the local commercial real estate sub-lease market. As a result, the Company recorded an impairment charge of $0.5 million to selling, general and administrative. In November 2014, the Company entered into a lease for additional laboratory space in Lexington, Massachusetts. The lease term commenced in April 2015 and extended for six years . The rent expense, inclusive of the escalating rent payments, is recognized on a straight-line basis over the lease term. As an incentive to enter into the lease, the landlord paid approximately $ 1.4 million of the $ 2.2 million space build-out costs. In connection with this lease agreement, the Company paid a security deposit of $ 281,000 , which is recorded as a component of both prepaid expenses and other current assets and other assets in the consolidated balance sheets. In October 2020, the Company entered into an amendment to extend the term of the lease to October 31, 2025 . In accordance with this amendment, the Company paid a replacement security deposit of $ 130,977 , which is classified as restricted cash at December 31, 2020 and received the initial $ 281,000 security deposit in return . This amendment resulted in an increase to the operating lease right-of use assets and lease liability accounts on the balance sheet of $ 1.8 million and $ 1.9 million, respectively, at December 31, 2020. Operating leases are amortized over the lease term and included in costs and expenses in the consolidated statement of operations and comprehensive loss. Variable lease costs are recognized in costs and expenses in the consolidated statement of operations and comprehensive loss as incurred. Finance Leases In October 2015, the Company signed a $10.0 million Credit Facility (the “Credit Facility”) to fund capital equipment needs. As one of the conditions of the Term Loan Agreement, the Credit Facility was capped at a maximum of $5.0 million. Under the Credit Facility, the lender funded capital equipment purchases presented by the Company. The Company repaid the amounts borrowed in 36 equal monthly installments from the date of the amount funded. At the end of the 36-month lease term, the Company had the option to (a) repurchase the leased equipment at the lesser of fair market value or 10% of the original equipment value, (b) extend the applicable lease for a specified period of time, which would not be less than one year, or (c) return the leased equipment to the lessor. In April 2016 and June 2016, the Company completed the first two draws under the Credit Facility of $2.1 million and $2.5 million, respectively. The Company made monthly payments of $67,000 under the first draw and $79,000 under the second draw. The property and equipment from the borrowings under the Credit Facility were treated as finance leases and were included in property and equipment on the balance sheet. The amortization of the assets conveyed under the Credit Facility was included as a component of depreciation expense. During the year ended December 31, 2019, the Company repurchased the equipment for $0.3 million in accordance with the terms of the Credit Facility. The following table summarizes the effect of operating and finance lease costs in the Company’s consolidated statement of operations and comprehensive loss (in thousands): Lease cost Year ended December 31, 2020 Year ended December 31, 2019 Finance lease cost: Amortization of right-of-use assets $ — $ 235 Interest on lease liabilities — 36 Operating lease cost 1,945 1,995 Variable lease cost 754 659 Total lease cost $ 2,699 $ 2,925 The following table summarizes supplemental information for the Company’s operating leases: Other information Year ended December 31, 2020 Year ended December 31, 2019 Weighted-average remaining lease term - operating leases (in years) 7.1 1.9 Weighted-average discount rate - operating leases 11.9 % 11.9 % The minimum lease payments for the next five years and thereafter is expected to be as follows (in thousands): December 31, 2020 Maturity of lease liabilities Operating Leases 2021 $ 2,440 2022 2,345 2023 2,290 2024 2,358 2025 2,331 Thereafter 5,851 Total lease payments $ 17,615 Less: effect of discounting (5,931 ) Present value of lease liabilities $ 11,684 The following table summarizes the presentation of the Company’s operating leases in its consolidated balance sheets (in thousands): Leases Classification December 31, 2020 December 31, 2019 Assets Operating lease assets Operating lease assets 11,034 3,360 Total lease assets $ 11,034 $ 3,360 Liabilities Current Operating Accrued expenses and other current liabilities $ 1,151 $ 1,983 Noncurrent Operating Noncurrent operating lease liabilities 10,533 1,873 Total lease liabilities $ 11,684 $ 3,856

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	13. Commitments and Contingencies Guarantees As permitted under Delaware law, the Company indemnifies its officers and directors for certain events or occurrences while each such officer or director is, or was, serving at the Company’s request in such capacity. The term of the indemnification is the officer’s or director’s lifetime. The maximum potential amount of future payments the Company could be required to make is unlimited; however, the Company has directors’ and officers’ liability insurance coverage that limits its exposure and enables the Company to recover a portion of any future amounts paid. The Company leases office, laboratory and manufacturing space under noncancelable operating leases. The Company has standard indemnification arrangements under the leases that require it to indemnify the landlords against all costs, expenses, fines, suits, claims, demands, liabilities, and actions directly resulting from any breach, violation or nonperformance of any covenant or condition of the Company’s leases. In the ordinary course of business, the Company enters into indemnification agreements with certain suppliers and business partners where the Company has certain indemnification obligations limited to the costs, expenses, fines, suits, claims, demands, liabilities and actions directly resulting from the Company’s gross negligence or willful misconduct, and in certain instances, breaches, violations or nonperformance of covenants or conditions under the agreements. As of December 31, 2020 and December 31, 2019, 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. Leases Refer to Note 12, Leases, for discussion of the commitments associated with the Company’s leases. License Agreement In 2006, the Company entered into a license agreement with a third party, pursuant to which the third party granted the Company an exclusive, worldwide, sublicensable license under certain patent rights to make, use, import and commercialize products and processes for diagnostic, industrial and research and development purposes. The Company agreed to pay an annual license fee ranging from $5,000 to $25,000 for the royalty‑bearing license to certain patents. For the years ended December 31, 2020 and 2019, the Company incurred immaterial amounts for regulatory milestones, license fees and reimbursed patent costs under the agreement. The Company also issued a total of 84,678 shares of common stock pursuant to the agreement in 2006 and 2007, which were recorded at fair value at the date of issuance. The Company is required to pay royalties on net sales of products and processes that are covered by patent rights licensed under the agreement at a percentage ranging between 0.5% - 3.5%, subject to reductions and offsets in certain circumstances, as well as a royalty on net sales of products that the Company sublicenses at 10% of specified gross revenue. Royalties that became due under this agreement for the year ended December 31, 2020 were $0.1 million and for the year ended December 31, 2019 were immaterial. Transition Agreement On July 30, 2019, the Company announced that founding CEO John McDonough was named Executive Chairman of the Board until a successor is named at which time Mr. McDonough will become non-executive Chairman of the Board. John Sperzel was named CEO in January 2020. In connection with John McDonough’s transition to Non-Executive Chairman of the Board from CEO, the Company agreed to transition payments and health benefits to be paid over the 15 month period following Mr. Sperzel’s start date. Accrued expenses include amounts related to Mr. McDonough’s transition payments and health benefits of $0.2 million and $1.2 million at December 31, 2020 and 2019, respectively

401(k) Savings Plan

401(k) Savings Plan	12 Months Ended
	Dec. 31, 2020
Compensation And Retirement Disclosure [Abstract]
401(k) Savings Plan	14. 401(k) Savings Plan In March, 2008, the Company established a retirement savings plan under Section 401(k) of the Internal Revenue Code (the “401(k) Plan”). The 401(k) Plan covers substantially all employees of the Company who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pretax basis. Company contributions to the 401(k) Plan may be made at the discretion of the Board of Directors. Company contributions to the 401(k) Plan were $163,000 and $195,000 for the years ended December 31, 2020 and 2019, respectively.

Co-Development Agreements

Co-Development Agreements	12 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Co-Development Agreements	15. Co-Development Agreements Canon US Life Sciences On February 3, 2015, the Company entered into a Co-Development Partnership Agreement (the “Co-Development Agreement”) with Canon U.S. Life Sciences, Inc. (“Canon US Life Sciences”) to develop a diagnostic test panel to rapidly detect Lyme disease. On September 21, 2016, Canon became a related party when the Company sold the Canon Shares for an aggregate cash purchase price of $39.7 million, which represented 19.9% of the outstanding shares of common stock of the Company. Under the terms of the Co-Development Agreement, the Company received an upfront payment of $2.0 million from Canon US Life Sciences and the agreement includes an additional $6.5 million of consideration upon achieving certain development and regulatory milestones for total aggregate payments of up to $8.5 million. In October 2015, the Company achieved a specified technical requirement and received $1.5 million related to the achievement of the milestone. In May 2018, the Company achieved the next milestone and received $2.0 million. As of December 31, 2019, the Company had determined that it will not achieve the final regulatory milestone of $3.0 million prior to the termination of this agreement and therefore, as of December 31, 2019, all revenue related to the Co-Development Agreement had been recognized. All payments under the Co-Development Agreement were non-refundable once received. The Company will retain exclusive worldwide commercialization rights of any products developed under the Co-Development 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 Co-Development Agreement. Either party may terminate the Co-Development Agreement upon the occurrence of a material breach by the other party (subject to a cure period). The Company evaluated the promised goods and services under the Co-Development Agreement and determined that the Co-Development Agreement included one The Co-Development Agreement was completed in 2019 and the Company did not record any revenue for the year ended December 31, 2020 and recorded revenue of $0.5 million for the year ended December 31, 2019, respectively. CARB-X In March 2018, the Company was awarded a grant of up to $2.0 million from CARB-X. The collaboration with CARB-X will be used to accelerate the development of new tests to identify bacterial pathogens and resistance markers directly in whole blood more rapidly than is possible using today’s diagnostic tools. The new tests aim to expand the T2Dx instrument product line by detecting 20 additional bacterial species and resistance targets, with a focus on blood borne pathogens on the United States Centers for Disease Control and Prevention (“CDC”) antibiotic resistance threat list. Under this cost-sharing agreement, the Company may be reimbursed up to $1.1 million, with the possibility of up to an additional $0.9 million based on the achievement of certain project milestones. In January 2019, the Company was awarded the $0.9 million reimbursement option. CARB-X was completed in 2019 and as such, the Company did not record any revenue for the year ended December 31, 2020. The Company recorded revenue of $0.9 million for the year ended December 31, 2019 under the CARB-X Agreement. US Government Contract In September 2019, the Biomedical Advanced Research and Development Authority (“BARDA”) awarded the Company a milestone-based contract, with an initial value of $6.0 million, and a potential value of up to $69.0 million, if BARDA awards all contract options. BARDA operates within the Office of the Assistant Secretary for Preparedness and Response (“ASPR”) at the U.S. Department of Health and Human Services’ (“HHS”). If BARDA awards and the Company completes all options, the Company’s management believes it will enable a significant expansion of the Company’s current portfolio of diagnostics for sepsis-causing pathogen and antibiotic resistance genes. In September 2020, the Company completed the initial award and BARDA exercised the first contract option valued at $10.5 . The Company recorded contribution revenue of $6.4 million and $1.5 million for the years ended December 31, 2020 and 2019, respectively, under the BARDA contract.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	16. Subsequent Events Term Loan Agreement In January 2021, the Term Loan Agreement was amended to extend the interest-only payment period until the December 30, 2022 maturity, to extend the initial principal repayment until the December 30, 2022 maturity, and to significantly reduce the minimum product revenue target for the twenty-four month period beginning on January 1, 2020. The Company did not pay or provide any consideration in exchange for this amendment.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The Company’s financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). The Company’s 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.
Use of Estimates	Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The Company utilizes certain estimates in the determination of the accounts receivable allowance, the excess and obsolete inventory, the net realizable value of inventory, the fair value of its stock options, as well as restricted stock units that have market conditions, deferred tax valuation allowances, revenue recognition, expenses relating to research and development contracts, accrued expenses, the fair value of a derivative liability, the fair value of warrants and classification of the value of instrument raw material and work-in-process inventory between inventory and property and equipment. The Company bases its estimates on historical experience and other market ‑
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 ‑
Geographic Information	Geographic Information The Company sells its products domestically and internationally. International sales to a single country did not exceed 10% of total revenue in any year. Total international sales were approximately $2.0 million or 11% of total revenue in 2020 and $2.8 million or 34% of total revenue in 2019. As of December 31, 2020 and 2019, the Company had outstanding receivables of $0.5 million and $1.2 million, respectively, from customers located outside of the U.S.
Off Balance Sheet Risk and Concentrations of Risk	Off ‑ The Company has no significant off-balance sheet risks, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Cash and cash equivalents are financial instruments that potentially subject the Company to concentrations of credit risk. At December 31, 2020, substantially all of the Company’s cash, cash equivalents and marketable securities were deposited in accounts at two financial institutions, with the majority of marketable securities invested in certificates of deposit and U.S. treasury securities. At December 31, 2019, substantially all of the Company’s cash was deposited in accounts at one financial institution, with a portion invested in money market funds that are invested in short-term U.S. government agency securities. The Company maintains its cash deposits, which at times may exceed the federally insured limits, with a large financial institution and, accordingly, the Company believes such funds are subject to minimal credit risk. The Company derived approximately 36% of its total revenue from one customer for the year ended December 31, 2020 and 19% of its total revenue from the same customer for the year ended December 31, 2019. For the year ended December 31, 2020, the Company derived approximately 11% of its total revenue from a second customer and 6% of its total revenue from a third customer. For the year ended December 31, 2019, the Company derived approximately 11% of its total revenue from a second customer and 8% of its total revenue from a third customer. At December 31, 2020, the Company had two customers that represented 20% and 17%, respectively, of its accounts receivable balance. At December 31, 2019, the Company had two customers that represented 27% and 10%, respectively, of its accounts receivable balance. The Company relies on single-source suppliers for some components and materials used in its products and product candidates. The Company has entered into supply agreements with most of its suppliers to help ensure component availability and flexible purchasing terms with respect to th e purchase of such components. While the Company believes replacement suppliers exist for all components and materials obtained from single sources, establishing additional or replacement suppliers for any of these components or materials, if required, may not be accomplished quickly. Even if the Company is able to find a replacement supplier, the replacement supplier would need to be qualified and may require additional regulatory authority approval, which could result in further delay. If third-party suppliers fail to deliver the required commercial quantities of materials on a timely basis and at commercially reasonable prices, and the Company is unable to find one or more replacement suppliers capable of production at a substantially equivalent cost in substantially equivalent volumes and quality on a timely basis, the continued commercialization of products, the supply of products to customers and the development of any future products would be delayed, limited or prevented, which could have an adverse impact on the business.
Cash Equivalents	Cash Equivalents Cash equivalents include all highly liquid investments with original maturities of 90 days or less. Cash equivalents consist of certificates of deposit and government securities as of December 31, 2020 and money market funds invested in short-term U.S. government agency securities as of December 31, 2019.
Marketable Securities	Marketable Securities The Company’s marketable securities typically consist of certificates of deposit and U.S. treasury securities, which are classified as available-for-sale and included in current and non-current assets. Available-for-sale debt securities are carried at fair value with unrealized gains and losses reported as a component of stockholders’ equity (deficit) in accumulated other comprehensive income. Realized gains and losses, if any, are included in other income in the consolidated statements of operations. Available-for-sale securities are reviewed for possible impairment at least quarterly, or more frequently if circumstances arise that may indicate impairment. When the fair value of the securities declines below the amortized cost basis, impairment is indicated and it must be determined whether it is other than temporary. Impairment is considered to be other than temporary if the Company: (i) intends to sell the security, (ii) will more likely than not be forced to sell the security before recovering its cost, or (iii) does not expect to recover the security’s amortized cost basis. If the decline in fair value is considered other than temporary, the cost basis of the security is adjusted to its fair market value and the realized loss is reported in earnings. Subsequent increases or decreases in fair value are reported as a component of stockholders’ equity (deficit) in accumulated other comprehensive income. There were no other-than-temporary unrealized losses as of December 31, 2020. The following table summarizes the Company’s marketable securities at December 31, 2020 (in thousands): December 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Certificates of deposit $ 1,250 $ 1 $ — $ 1,251 U.S. treasury securities 34,139 8 — 34,147 Total $ 35,389 $ 9 $ — $ 35,398 The following table summarizes the maturities of the Company’s marketable securities at December 31, 2020 (in thousands): December 31, 2020 Amortized Cost Fair Value Due in less than 1 year $ 25,387 $ 25,396 Due in 1-2 years 10,002 10,002 Total $ 35,389 $ 35,398
Accounts Receivable	Accounts Receivable The Company’s accounts receivable consists of amounts due from product sales to commercial customers and from research and development arrangements with partners. At each reporting period, management reviews historical loss information, characteristics of our customers, our credit practices and the economic conditions, along with all outstanding balances to determine if the facts and circumstances indicate the need for a credit loss allowance. The Company does not require collateral and did not have an allowance for doubtful accounts at December 31, 2020 or 2019.
Inventories	Inventories Inventories are stated at the lower of cost or net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials, direct labor, and manufacturing overhead, on a first-in, first-out basis. The Company performs an assessment of the recoverability of capitalized inventory during each reporting period and records a charge to expense for cost basis in excess of net realizable value in the period in which the impairment is first identified, and writes down any excess and obsolete inventories as appropriate. Shipping and handling costs incurred for inventory purchases are capitalized and recorded upon sale in cost of product revenues in the consolidated statements of operations and comprehensive loss or are included in the value of T2-owned instruments and components, a component of property and equipment, net, and depreciated. The Company capitalizes inventories in preparation for sales of products when the related product candidates are considered to have a high likelihood of regulatory clearance, which for the T2Dx Instrument, T2Candida and T2Bacteria was upon the achievement of regulatory clearance and upon EUA for T2SARS-CoV-2, and the related costs are expected to be recoverable through sales of the inventories. In addition, the Company capitalizes inventories related to the manufacture of instruments that have a high likelihood of regulatory clearance, which for the T2Dx Instrument was upon the achievement of regulatory clearance, and will be retained as the Company’s assets, upon determination that the instrument has alternative future uses. In determining whether or not to capitalize such inventories, the Company evaluates, among other factors, information regarding the product candidate’s status of regulatory submissions and communications with regulatory authorities, the outlook for commercial sales and alternative future uses of the product candidate. Costs associated with development products prior to satisfying the inventory capitalization criteria are charged to research and development expense as incurred. The Company classifies instruments that are T2-owned, as a component of property and equipment. Raw material and work-in-process inventories that are expected to be used to produce T2-owned instruments, based on the Company’s business model and forecast, are also classified as property and equipment. T2-owned instruments are instruments that are manufactured and placed with customers in connection with reagent rental agreements, or are used for internal purposes. The components of inventory consist of the following (in thousands): December 31, December 31, 2020 2019 Raw materials $ 1,496 $ 1,617 Work-in-process 1,374 1,227 Finished goods 766 755 Total inventories, net $ 3,636 $ 3,599
Fair Value Measurements	Fair Value Measurements The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC 820, Fair Value Measurements and Disclosures Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability, and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The hierarchy defines three levels of valuation inputs: Level 1 — Quoted unadjusted prices for identical instruments in active markets. Level 2 — Quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model ‑ Level 3 — Model derived valuations in which one or more significant inputs or significant value drivers are unobservable, including assumptions developed by the Company. The fair value hierarchy prioritizes valuation inputs based on the observable nature of those inputs. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability (Note 3). For certain financial instruments, including accounts receivable, prepaid expenses and other current assets, accounts payable and accrued expenses, the carrying amounts approximate their fai r values as of December 31, 20 20 and 201 9 because of their short-t erm nature. At December 31, 20 20 and 201 9 , the fair value of the derivative liability was determined using Level 3 inputs using a valuation model that includes assumptions from the Company (Note 3 ).
Property and Equipment	Property and Equipment Property and equipment are recorded at cost and depreciated over their estimated useful lives using the straight‑line method. Property and equipment, net, includes assets under capital leases. Property and equipment includes raw materials and work-in-process inventory that are expected to be used or used to produce T2-owned instruments based on the Company’s business model and forecast, and finished instruments that will be used for internal research and development, clinical studies or reagent rental agreements with customers. Completed T2-owned instruments are placed in service once installation procedures are completed. Construction in progress is primarily comprised of equipment that has not been placed in service.
Leases	Leases Pursuant to Topic 842, Leases In accordance with the guidance in ASC 842, components of a lease should be split into three categories: lease components (e.g. land, building, etc.), non-lease components (e.g. common area maintenance, consumables, etc.), and non-components (e.g. property taxes, insurance, etc.). Then the fixed and in-substance fixed contract consideration (including any related to non-components) must be allocated based on the respective relative fair values to the lease components and non-lease components. The Company made the policy election to not separate lease and non-lease components. Each lease component and the related non-lease components are accounted for together as a single component.
Revenue Recognition	Revenue Recognition The Company generates revenue from the sale of instruments, consumable diagnostic tests, related services, reagent rental agreements and research and development agreements with third parties. Pursuant to ASC 606, Revenue from Contracts with Customers • Identification of a contract with a customer • Identification of the performance obligations in the contract • Determination of the transaction price • Allocation of the transaction price to the performance obligations • Recognition of revenue as a performance obligation is satisfied. The amount of revenue recognized reflects the consideration the Company expects to be entitled to receive in exchange for these goods and services. Once a contract is determined to be within the scope of ASC 606 at contract inception, the Company reviews the contract to determine which performance obligations the Company must deliver and which of these performance obligations are distinct. The Company recognizes as revenues the amount of the transaction price that is allocated to the respective performance obligation when the performance obligation is satisfied or as it is satisfied. Generally, the Company's performance obligations are transferred to customers at a point in time, typically upon shipment, or over time, as services are performed. Most of the Company’s contracts with distributors in geographic regions outside the United States contain only a single performance obligation, whereas most of the Company’s contracts with direct sales customers in the United States contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative standalone selling price basis. Excluded from the transaction price are sales tax and other similar taxes which are presented on a net basis. Product revenue is generated by the sale of instruments and consumable diagnostic tests predominantly through the Company’s direct sales force in the United States and distributors in geographic regions outside the United States. The Company does not offer product return or exchange rights (other than those relating to defective goods under warranty) or price protection allowances to its customers, including its distributors. Payment terms granted to distributors are the same as those granted to end-user customers and payments are not dependent upon the distributors’ receipt of payment from their end-user customers. The Company either sells instruments to customers and international distributors, or retains title and places the instrument at the customer site pursuant to a reagent rental agreement. When an instrument is purchased by a customer or international distributor, the Company recognizes revenue when the related performance obligation is satisfied (i.e. when the control of an instrument has passed to the customer; typically, at shipping point). When the instrument is placed under a reagent rental agreement, the Company’s customers generally agree to fixed term agreements, which can be extended, and incremental charges on each consumable diagnostic test purchased. Revenue from the sale of consumable diagnostic tests (under a reagent rental agreement) is recognized upon shipment. The transaction price from consumables purchases is allocated between the lease of the instrument (under a contingent rent methodology as provided for in ASC 842, Leases Revenue from the sale of consumable diagnostic tests (under instrument purchase agreements) is recognized upon shipment. Shipping and handling costs billed to customers in connection with a product sale are recorded as a component of the transaction price and allocated to product revenue in the consolidated statements of operations and comprehensive loss as they are incurred by the Company in fulfilling its performance obligations. Direct sales of instruments include warranty, maintenance and technical support services typically for one year following the installation of the purchased instrument (“Maintenance Services”). Maintenance Services are separate performance obligations as they are service based warranties and are recognized on a straight-line basis over the service delivery period. After the completion of the initial Maintenance Services period, customers have the option to renew or extend the Maintenance Services typically for additional Fees paid to member-owned group purchasing organizations (“GPOs”) are deducted from related product revenues. The Company warrants that consumable diagnostic tests will be free from defects, when handled according to product specifications, for the stated life of the product. To fulfill valid warranty claims, the Company provides replacement product free of charge. Accordingly, the Company accrues warranty expense associated with the estimated defect rates of the consumable diagnostic tests. Revenue earned from activities performed pursuant to research and development agreements is reported as research revenue in the consolidated statements of operations and comprehensive loss, and is recognized over time using an input method as the work is completed. 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. Milestones are contingent on the occurrence of future events and are considered variable consideration being constrained until the Company believes a significant revenue reversal will not occur. Refer to Note 15 for further details regarding the Company’s research and development arrangements. Pursuant to ASU No. 2018-08, Not-For-Profit Entities – Clarifying the Scope and the Accounting Guidance for Contributions Received and Contributions Made (“ASU 2018-08”), grants received, including cost reimbursement agreements, are assessed to determine if the agreement should be accounted for as an exchange transaction or a contribution. An agreement is accounted for as a contribution if the resource provider does not receive The Company has a significant development contract with BARDA and should BARDA reduce, cancel or not grant additional milestone projects the Company’s ability to continue our future product development may be impacted. Disaggregation of Revenue The Company disaggregates revenue from contracts with customers by type of products and services, as it best depicts how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors. The following table disaggregates total revenue by major source (in thousands): Year ended December 31, 2020 2019 Product Revenue Instruments $ 3,139 $ 2,280 Consumables 8,423 2,863 Instrument Rentals 115 184 Total Product Revenue 11,677 5,327 Research Revenue 11 563 Contribution Revenue 6,442 2,445 Total Revenue $ 18,130 $ 8,335 Remaining Performance Obligations Remaining performance obligations represent the transaction price of firm orders for which work has not been performed or goods and services have not been delivered. As of December 31, 2020 and 2019, the aggregate amount of transaction price allocated to remaining performance obligations for contracts with an original duration greater than one year was $0.5 million and $0.2 million, respectively. The Company does not disclose the value of unsatisfied performance obligations for (i) contracts with an original expected length of one year or less and (ii) contracts for which it recognizes revenue at the amount to which it has the right to invoice for services performed. The Company expects to recognize revenue on the remaining performance obligations over the next 23 months. Significant Judgments Certain contracts with customers include promises to transfer multiple products and services to a customer. Determining whether products and services are considered distinct performance obligations that should be accounted for separately versus together may require significant judgment. Once the performance obligations are determined, the Company determines the transaction price, which includes estimating the amount of variable consideration, based on the most likely amount, to be included in the transaction price, if any. The Company then allocates the transaction price to each performance obligation in the contract based on a relative stand-alone selling price method. The corresponding revenue is recognized as the related performance obligations are satisfied as discussed in the revenue categories above. Judgment is required to determine the standalone selling price for each distinct performance obligation. The Company determines standalone selling price based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, we estimate the standalone selling price taking into account available information such as a range of selling prices, market conditions and the expected costs and margin related to the performance obligations. Contract Assets and Liabilities The Company did not record any contract assets at December 31, 2020 and 2019. The Company’s contract liabilities consist of upfront payments for research and development contracts and maintenance services on instrument sales. Contract liabilities are classified in deferred revenue as current or noncurrent based on the timing of when revenue is expected to be recognized. At December 31, 2020 and 2019, the Company had contract liabilities of $0.6 million and $0.2 million, respectively. Revenue recognized in the year-ended December 31, 2020 relating to contract liabilities at December 31, 2019 was $0.2 million, and related to straight-line revenue recognition associated with maintenance agreements. Costs to Obtain and Fulfill a Contract The Company capitalizes commission expenses paid to sales personnel that are recoverable and incremental to obtaining capital purchase agreements within the United States. These costs are classified as prepaid expenses and other current assets and other assets, based on their current or non-current nature, respectively. The Company capitalizes only those costs that are determined to be incremental and would not have occurred absent the customer contract. These capitalized costs are amortized as selling, general and administrative costs on a straight line basis over the expected period of benefit. These costs are reviewed periodically for impairment. At December 31, 2020, the Company capitalized costs to fulfill contracts of $0.1 million in prepaid and other current assets and $0.1 million in other non-current assets. At December 31, 2019, no costs to obtain or fulfill contracts were capitalized.
Cost of Product Revenue	Cost of Product Revenue Cost of product revenue includes the cost of materials, direct labor and manufacturing overhead costs used in the manufacture of consumable diagnostic tests sold to customers, related warranty and license and royalty fees. Cost of product revenue also includes depreciation on T2-owned revenue generating T2Dx instruments that have been placed with customers under reagent rental agreements; costs of materials, direct labor and manufacturing overhead costs on the T2Dx instruments sold to customers; and other costs such as customer support costs, royalties and license fees, warranty and repair and maintenance expense on the T2Dx instruments that have been placed with customers under reagent rental agreements.
Research and Development Costs	Research and Development Costs Costs incurred in the research and development of the Company’s product candidates are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including activities associated with performing services under research revenue arrangements, costs associated with the enhancements of developed products and include salaries and benefits, stock compensation, research‑related facility and overhead costs, laboratory supplies, equipment and contract services.
Impairment of Long-lived Assets	Impairment of Long-lived Assets The Company reviews long‑lived assets, including capitalized T2 owned instruments and components and capitalized costs to fulfill a contract, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indications of impairment exist, projected future undiscounted cash flows associated with the asset or asset group are compared to the carrying amount to determine whether the asset’s value is recoverable. During this review, the Company reevaluates the significant assumptions used in determining the original cost and estimated lives of long‑lived assets. Although the assumptions may vary from asset to asset, they generally include operating results, changes in the use of the asset, cash flows and other indicators of value. Management then determines whether the remaining useful life continues to be appropriate or whether there has been an impairment of long‑lived assets based primarily upon whether expected future undiscounted cash flows are sufficient to support the assets’ recovery. If impairment exists, the Company would adjust the carrying value of the asset to fair value, generally determined by a discounted cash flow analysis. If the carrying value of the asset exceeds such projected undiscounted cash flows, the asset will be written down to its estimated fair value. The Company recorded an impairment of property and equipment of $0.6 million and an impairment of an operating lease asset of $0.5 million during the year ended December 31, 2020 and did not record any impairment expense during the year ended December 31, 2019.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non‑owner sources. Comprehensive loss consists of net loss and other comprehensive loss, which includes certain changes in equity that are excluded from net loss. The Company had a net change in available-for-sale securities for the year ended December 31, 2020. The Company’s comprehensive loss equals reported net loss for the year ended December 31, 2019.
Stock Based Compensation	Stock-Based Compensation The Company issues stock-based awards to employees, generally in the form of stock options, restricted stock units and restricted stock awards. The Company accounts for stock-based awards in accordance with FASB ASC Topic 718, Compensation-Stock Compensation The Company estimates the fair value of the stock-based awards to employees using the Black-Scholes-Merton option pricing model, which requires the input of highly subjective assumptions, including (a) the expected volatility of the stock, (b) the expected term of the award, (c) the risk-free interest rate and (d) expected dividends. The Company estimates expected volatility based on the historical volatility of the stock using the daily closing prices during the equivalent period of the calculated expected term of its stock‑based awards. The Company has estimated the expected life of the employee stock options using the “simplified” method, whereby the expected life equals the average of the vesting term, and the original contractual term of the option. The risk-free interest rates for periods within the expected life of the option are based on the U.S. Treasury yield curve in effect during the period in which the options were granted. The Company has not paid, and does not anticipate paying, cash dividends on shares of common stock; therefore, the expected dividend yield is assumed to be zero. The Company elected an accounting policy to estimate forfeitures at the time of grant and revise those estimates in subsequent periods if actual forfeitures differ from the estimates. Historical data is used to estimate pre-vesting option forfeitures and stock-based compensation expense is only recorded for those awards that are expected to vest. To the extent that actual forfeitures differ from the estimates, the difference is recorded as a cumulative adjustment in the period the estimates were revised. Stock-based compensation expense recognized in the financial statements is based on awards that are ultimately expected to vest. If the actual forfeiture rate is materially different from the estimate, stock-based compensation expense could be different from what we have recorded in the current period. The Company estimate s the fair value of restricted stock units with market conditions on the date of grant using a Monte Carlo simulation. The compensation cost for restricted stock units with market conditions is being recorded over the derived service period. If a market condition is achieved prior to completion of the derived service period, the remaining compensation cost will be recognized immediately. These assumptions used to determine stock compensation expense represent the Company’s best estimates, but the estimates involve inherent uncertainties and the application of judgment. As a result, if factors change and the Company uses significantly different assumptions or estimates, stock-based compensation expense could be materially different. Refer to Note 8 for further details on the Company’s stock-based compensation plan.
Income Taxes	Income Taxes The Company provides for income taxes using the liability method. The Company provides deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the Company’s financial statement carrying amounts and the tax basis of assets and liabilities using enacted tax rates expected to be in effect in the years in which the differences are expected to reverse. A valuation allowance is provided to reduce the deferred tax assets to the amount that will more likely than not be realized. The Company applies ASC 740 Income Taxes
Guarantees	Guarantees As permitted under Delaware law, the Company indemnifies its officers and directors for certain events or occurrences while each such officer or director is, or was, serving at the Company’s request in such capacity. The term of the indemnification is the officer’s or director’s lifetime. The maximum potential amount of future payments the Company could be required to make is unlimited; however, the Company has directors’ and officers’ liability insurance coverage that limits its exposure and enables the Company to recover a portion of any future amounts paid. The Company leases office, laboratory and manufacturing space under noncancelable operating leases. The Company has standard indemnification arrangements under the leases that require it to indemnify the landlords against all costs, expenses, fines, suits, claims, demands, liabilities, and actions directly resulting from any breach, violation or nonperformance of any covenant or condition of the Company’s leases. In the ordinary course of business, the Company enters into indemnification agreements with certain suppliers and business partners where the Company has certain indemnification obligations limited to the costs, expenses, fines, suits, claims, demands, liabilities and actions directly resulting from the Company’s gross negligence or willful misconduct, and in certain instances, breaches, violations or nonperformance of covenants or conditions under the agreements. As of December 31, 2020 and December 31, 2019, 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.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing net loss 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 purposes of the diluted net loss per share calculation, stock options and unvested restricted stock and restricted stock contingently issuable upon achievement of certain market conditions are considered to be common stock equivalents, but have been excluded from the calculation of diluted net loss per share, as their effect 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.
Recent Accounting Standards	Recent Accounting Standards 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. Accounting Standards Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Instruments In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement In November 2018, the FASB issued ASU No. 2018-18, Collaborative Arrangements Collaborative Arrangements Revenue from Contracts with Customers Accounting Standards Issued, Not Adopted In December 2019, the FASB issued ASU No. 2019-12, Income Taxes: Simplifying the Accounting for Income Taxes In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity's Own Equity (Subtopic 815-40)—Accounting for Convertible Instruments and Contracts in an Entity's Own Equity

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Marketable Securities	The following table summarizes the Company’s marketable securities at December 31, 2020 (in thousands): December 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Certificates of deposit $ 1,250 $ 1 $ — $ 1,251 U.S. treasury securities 34,139 8 — 34,147 Total $ 35,389 $ 9 $ — $ 35,398
Summary of Maturities of Marketable Securities	The following table summarizes the maturities of the Company’s marketable securities at December 31, 2020 (in thousands): December 31, 2020 Amortized Cost Fair Value Due in less than 1 year $ 25,387 $ 25,396 Due in 1-2 years 10,002 10,002 Total $ 35,389 $ 35,398
Schedule of inventory	The components of inventory consist of the following (in thousands): December 31, December 31, 2020 2019 Raw materials $ 1,496 $ 1,617 Work-in-process 1,374 1,227 Finished goods 766 755 Total inventories, net $ 3,636 $ 3,599
Disaggregation of Revenue by Major Source	The following table disaggregates total revenue by major source (in thousands): Year ended December 31, 2020 2019 Product Revenue Instruments $ 3,139 $ 2,280 Consumables 8,423 2,863 Instrument Rentals 115 184 Total Product Revenue 11,677 5,327 Research Revenue 11 563 Contribution Revenue 6,442 2,445 Total Revenue $ 18,130 $ 8,335

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of Financial Assets and Liabilities at Fair value on a Recurring Basis	The Company measures the following financial assets at fair value on a recurring basis. There were no transfers between levels of the fair value hierarchy during any of the periods presented. The following tables set forth the Company’s financial assets and liabilities carried at fair value categorized using the lowest level of input applicable to each financial instrument as of December 31, 2020 and 2019 (in thousands): Quoted Prices in Active Significant Markets for Other Significant Balance at Identical Observable Unobservable December 31, Assets Inputs Inputs 2020 (Level 1) (Level 2) (Level 3) Assets: Certificates of deposit $ 1,251 $ — $ 1,251 $ — US Treasury securities 34,147 34,147 — — Restricted cash 551 551 — — $ 35,949 $ 34,698 $ 1,251 $ — Liabilities: Derivative liability $ 1,010 $ — $ — $ 1,010 $ 1,010 $ — $ — $ 1,010 Quoted Prices in Active Significant Markets for Other Significant Balance at Identical Observable Unobservable December 31, Assets Inputs Inputs 2019 (Level 1) (Level 2) (Level 3) Assets: Money market funds $ 4,301 $ 4,301 $ — $ — Restricted cash 180 180 — — $ 4,481 $ 4,481 $ — $ — Liabilities: Derivative liability $ 2,425 $ — $ — $ 2,425 $ 2,425 $ — $ — $ 2,425
Summary of Contingent Interest Payments	The estimated fair value of the derivative at December 31, 2020 was determined using a probability-weighted discounted cash flow model that includes contingent interest payments under the following scenarios: Range 4% contingent interest beginning in 2021 0 % 4% contingent interest beginning in 2022 90 %
Roll-Forward of Fair Value of Derivative Liability	The following table provides a roll-forward of the fair value of the derivative liability (in thousands): Balance at December 31, 2018 $ 2,142 Change in fair value of derivative liability, recorded as interest expense 283 Balance at December 31, 2019 2,425 Change in fair value of derivative liability, recorded as interest expense (1,415 ) Balance at December 31, 2020 $ 1,010

Supplemental Balance Sheet In_2

Supplemental Balance Sheet Information (Tables)	12 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Property and Equipment	Property and equipment consists of the following (dollar amounts in thousands) Estimated Useful December 31, December 31, Life (Years) 2020 2019 Office and computer equipment 3 $ 538 $ 538 Software 3 762 762 Laboratory equipment 5 5,179 4,747 Furniture 5-7 197 194 Manufacturing equipment 5 672 672 Manufacturing tooling and molds 0.5-5 255 255 T2-owned instruments and components 5 5,001 6,775 Leasehold improvements Lesser of useful life or remaining lease term 3,691 3,497 Construction in progress n/a 1,733 1,641 18,028 19,081 Less accumulated depreciation and amortization (14,257 ) (13,236 ) Property and equipment, net $ 3,771 $ 5,845
Components of Accrued Expenses	Accrued expenses consist of the following (in thousands): December 31, December 31, 2020 2019 Accrued payroll and compensation $ 3,629 $ 3,193 Accrued final fee — 2,445 Accrued research and development expenses 751 267 Accrued professional services 421 511 Accrued interest 940 908 Operating lease liabilities 1,151 1,983 Other accrued expenses 620 1,900 Total accrued expenses and other current liabilities $ 7,512 $ 11,207

Notes Payable (Tables)

Notes Payable (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of Debt	Future principal payments on the notes payable as of December 31, 2020 are as follows (in thousands): Year ended December 31, 2021 $ — 2022 48,077 2023 — 2024 — 2025 — Total before unamortized discount and issuance costs 48,077 Less: paid-in-kind interest (1,669 ) Less: unamortized discount and issuance costs (1,173 ) Total notes payable $ 45,235

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity	The following is a summary of option activity under the Stock Incentive Plans and Inducement Plan (in thousands, except term, share and per share amounts): Weighted-Average Weighted-Average Remaining Number of Exercise Price Per Contractual Term Aggregate Intrinsic Shares Share (In years) Value Outstanding at December 31, 2019 6,353,330 $ 4.95 7.29 $ 229 Granted 4,306,750 1.02 Exercised (49,563 ) 0.61 33 Forfeited (1,232,700 ) 3.04 Canceled (781,888 ) 5.43 Outstanding at December 31, 2020 8,595,929 3.24 7.75 1,011 Exercisable at December 31, 2020 4,098,314 4.98 6.57 272 Vested or expected to vest at December 31, 2020 7,650,363 $ 3.46 7.61 $ 845
Schedule of Estimated Assumptions Used to Calculate Weighted-Average Grant Date Fair Value of Options Granted	There were 49,563 options exercised in the year ended December 31, 2020 and 2,119 options exercised in the year ended December 31, 2019. The total intrinsic value of options exercised in the years ended December 31, 2020 and 2019 were immaterial. The weighted‑average fair values of options granted in the years ended December 31, 2020 and 2019 were $0.71 and $1.41 per share, respectively, and were calculated using the following estimated assumptions: Year ended December 31, 2020 2019 Weighted-average risk-free interest rate 1.35 % 1.97 % Expected dividend yield 0.00 % 0.00 % Expected volatility 92 % 78 % Expected terms 5.8 years 6.0 years
Schedule of Nonvested Restricted Stock Units Activity	The following is a summary of restricted stock unit activity under the 2014 Plan: Weighted-Average Number of Grant Date Fair Shares Value Nonvested at December 31, 2019 1,295,508 $ 4.19 Granted 1,380,923 0.89 Vested (331,433 ) 3.45 Forfeited (701,219 ) 3.37 Canceled — — Nonvested at December 31, 2020 1,643,779 $ 1.91
Schedule of Estimated Assumptions Used to Calculate Weighted-Average Fair Value of the Purchase Rights Granted	The fair value of the purchase rights granted under this plan was estimated on the date of grant and uses the following weighted-average assumptions, which were derived in a manner similar to those discussed in Note 2 relative to stock options: Year ended December 31, 2020 2019 Weighted-average risk-free interest rate 1.59 % 2.44 % Expected dividend yield 0.00 % 0.00 % Expected volatility 92 % 71 % Expected terms 0.5 years 0.5 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 resulting from awards granted under Stock Incentive Plans, the Inducement Plan and 2014 ESPP, that was recorded in the Company’s results of operations for the years presented (in thousands): Year ended December 31, 2020 2019 Cost of product revenue $ 221 $ 365 Research and development 777 1,184 Selling, general and administrative 2,901 3,888 Total stock-based compensation expense $ 3,899 $ 5,437

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss Per Share Applicable to Common Stockholders	The following table presents the calculation of basic and diluted net loss per share applicable to common stockholders (in thousands, except share and per share data): Year ended December 31, 2020 2019 Numerator: Net loss $ (46,798 ) $ (59,006 ) Denominator: Weighted-average number of common shares outstanding — basic and diluted 121,331,464 45,507,754 Net loss per share applicable to common stockholders — basic and diluted $ (0.39 ) $ (1.30 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings 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 their effect would have been anti ‑ Year ended December 31, 2020 2019 Options to purchase common shares 8,595,929 6,353,330 Restricted stock units 1,643,779 1,295,508 Warrants to purchase common stock 1,097,249 1,097,249 Total 11,336,957 8,746,087

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Reconciliation of the U.S. Federal Statutory Rate to the Company's Effective Tax Rate	The reconciliation of the U.S. federal statutory rate to the Company’s effective tax rate is as follows: Year Ended December 31, 2020 2019 Tax at statutory rates 21.0 % 21.0 % State income taxes 6.4 2.6 Permanent differences (1.9 ) (1.2 ) Research and development credits 1.4 1.0 Limitations on credits and net operating losses 0.1 (75.2 ) Change in valuation allowance (27.0 ) 51.8 Effective tax rate 0.0 % 0.0 %
Schedule Of Deferred Tax Assets	The significant components of the Company’s deferred tax asset consist of the following at December 31, 2020 and 2019 (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 61,551 $ 50,407 Tax credits 1,428 472 Other temporary differences 3,546 2,888 Start-up expenditures 2,672 2,716 Stock option expenses 3,382 3,450 Lease liability 3,170 987 Total deferred tax assets 75,749 60,920 Deferred tax asset valuation allowance (72,404 ) (59,764 ) Net deferred tax assets 3,345 1,156 Deferred tax liabilities: Right of use asset (2,994 ) (859 ) Prepaid expenses (351 ) (297 ) Net deferred taxes $ — $ —

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Schedule of Lease Cost	The following table summarizes the effect of operating and finance lease costs in the Company’s consolidated statement of operations and comprehensive loss (in thousands): Lease cost Year ended December 31, 2020 Year ended December 31, 2019 Finance lease cost: Amortization of right-of-use assets $ — $ 235 Interest on lease liabilities — 36 Operating lease cost 1,945 1,995 Variable lease cost 754 659 Total lease cost $ 2,699 $ 2,925
Schedule of Other Information Related to Leases	The following table summarizes supplemental information for the Company’s operating leases: Other information Year ended December 31, 2020 Year ended December 31, 2019 Weighted-average remaining lease term - operating leases (in years) 7.1 1.9 Weighted-average discount rate - operating leases 11.9 % 11.9 %
Schedule of Maturity of Lease Liabilities	The minimum lease payments for the next five years and thereafter is expected to be as follows (in thousands): December 31, 2020 Maturity of lease liabilities Operating Leases 2021 $ 2,440 2022 2,345 2023 2,290 2024 2,358 2025 2,331 Thereafter 5,851 Total lease payments $ 17,615 Less: effect of discounting (5,931 ) Present value of lease liabilities $ 11,684
Summary of Lease Assets and Liabilities	The following table summarizes the presentation of the Company’s operating leases in its consolidated balance sheets (in thousands): Leases Classification December 31, 2020 December 31, 2019 Assets Operating lease assets Operating lease assets 11,034 3,360 Total lease assets $ 11,034 $ 3,360 Liabilities Current Operating Accrued expenses and other current liabilities $ 1,151 $ 1,983 Noncurrent Operating Noncurrent operating lease liabilities 10,533 1,873 Total lease liabilities $ 11,684 $ 3,856

Nature of Business - Additional

Nature of Business - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Apr. 07, 2020	Dec. 31, 2019
Nature of Business
Cash, cash equivalents marketable securities and restricted cash	$ 52,700
Accumulated deficit	$ (422,975)		$ (376,177)
Substantial doubt about going concern, management's plans, substantial doubt alleviated	Management's plans to alleviate the conditions that raise substantial doubt include raising additional funding, earning payments pursuant to the Company’s Co- Development agreements, delaying certain research projects and capital expenditures and eliminating certain future operating expenses in order to fund operations at reduced levels for the Company to continue as a going concern for a period of 12 months from the date the financial statements are issued.
Substantial doubt about going concern, management's evaluation	Management has concluded the likelihood that its plan to successfully obtain sufficient funding from one or more of these sources or adequately reduce expenditures, while reasonably possible, is less than probable.
Substantial doubt about going concern, within one year	true
Minimum bid price of common stock for continued listing		$ 1
Term Loan Agreement [Member] | CRG [Member]
Nature of Business
Minimum cash balance	$ 5,000
Debt instrument covenant compliance revenue target achieved	$ 15,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)SegmentFinancialInstitution	Dec. 31, 2019USD ($)FinancialInstitution
Product Information [Line Items]
Number of operating segments | Segment	1
Total revenue	$ 18,130,000	$ 8,335,000
Outstanding receivable	$ 5,099,000	$ 2,825,000
Number of financial institutions in which cash was deposited | FinancialInstitution	2	1
Other-than-temporary unrealized losses	$ 0
Allowance for doubtful accounts	0	$ 0
Aggregate amount of transaction price allocated to remaining performance obligations for contracts with original duration greater than one year	$ 500,000	200,000
Remaining performance obligation, expected timing of satisfaction	The Company expects to recognize revenue on the remaining performance obligations over the next 23 months.
Contract assets	$ 0	0
Contract liabilities	600,000	200,000
Revenue recognized relating to contract liabilities	200,000
Costs to obtain or fulfill contract capitalized		0
Impairment of property and equipment	636,000	0
Impairment of operating lease asset	$ 523,000	$ 0
Expected dividend yield	0.00%
ASU 2016-13 [Member]
Product Information [Line Items]
Change in accounting principle accounting standards update adoption date	Jan. 1, 2020
Change in accounting principle accounting standards update adopted	true
Change in accounting principle accounting standards update immaterial effect	true
ASU 2018-13 [Member]
Product Information [Line Items]
Change in accounting principle accounting standards update adoption date	Jan. 1, 2020
Change in accounting principle accounting standards update adopted	true
ASU 2018-18 [Member]
Product Information [Line Items]
Change in accounting principle accounting standards update adoption date	Jan. 1, 2020
Change in accounting principle accounting standards update adopted	true
Change in accounting principle accounting standards update immaterial effect	true
Prepaid and Other Current Assets [Member]
Product Information [Line Items]
Costs to obtain or fulfill contract capitalized	$ 100,000
Other Non-Current Assets [Member]
Product Information [Line Items]
Costs to obtain or fulfill contract capitalized	$ 100,000
T2 Dx [Member]
Product Information [Line Items]
Maintenance Services period (in years)	1 year
Additional period for Maintenance Service option (in years)	1 year
Maximum [Member]
Product Information [Line Items]
Original expected period of contracts for which value of unsatisfied performance obligations not to be disclosed	1 year	1 year
Minimum [Member]
Product Information [Line Items]
Aggregate amount of transaction price allocated to remaining performance obligations, original duration	1 year	1 year
Non-US [Member]
Product Information [Line Items]
Total revenue	$ 2,000,000	$ 2,800,000
Outstanding receivable	$ 500,000	$ 1,200,000
Revenue [Member] | Geographic Concentration Risk [Member] | Non-US [Member]
Product Information [Line Items]
Total revenue (as a percent)	11.00%	34.00%
Revenue [Member] | Geographic Concentration Risk [Member] | Non-US [Member] | Maximum [Member]
Product Information [Line Items]
Total revenue (as a percent)	10.00%	10.00%
Revenue [Member] | Customer Concentration Risk [Member] | Customer One [Member]
Product Information [Line Items]
Total revenue (as a percent)	36.00%	19.00%
Revenue [Member] | Customer Concentration Risk [Member] | Customer Two [Member]
Product Information [Line Items]
Total revenue (as a percent)	11.00%	11.00%
Revenue [Member] | Customer Concentration Risk [Member] | Customer Three [Member]
Product Information [Line Items]
Total revenue (as a percent)	6.00%	8.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer One [Member]
Product Information [Line Items]
Total revenue (as a percent)	20.00%	27.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer Two [Member]
Product Information [Line Items]
Total revenue (as a percent)	17.00%	10.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Marketable Securities (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Marketable Securities [Line Items]
Amortized Cost	$ 35,389
Gross Unrealized Gains	9
Fair Value	35,398
Certificates of Deposit [Member]
Marketable Securities [Line Items]
Amortized Cost	1,250
Gross Unrealized Gains	1
Fair Value	1,251
U.S. Treasury Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	34,139
Gross Unrealized Gains	8
Fair Value	$ 34,147

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Summary of Maturities of Marketable Securities (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Accounting Policies [Abstract]
Marketable Securities, Amortized Cost, Due in less than 1 year	$ 25,387
Marketable Securities, Amortized Cost, Due in 1-2 years	10,002
Amortized Cost	35,389
Marketable Securities, Fair Value, Due in less than 1 year	25,396
Marketable Securities, Fair Value, Due in 1-2 years	10,002
Marketable Securities, Fair Value	$ 35,398

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Components of Inventory (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Net [Abstract]
Raw materials	$ 1,496	$ 1,617
Work-in-process	1,374	1,227
Finished goods	766	755
Total inventories, net	$ 3,636	$ 3,599

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Disaggregation of Total Revenue by Major Resource (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Total revenue	$ 18,130	$ 8,335
Product Instruments [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	3,139	2,280
Product Consumables [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	8,423	2,863
Instrument Rentals [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	115	184
Total Product Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	11,677	5,327
Research [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	11	563
Contribution Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	$ 6,442	$ 2,445

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets and Liabilities at Fair value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets:
Assets, fair value	$ 35,398
Estimate of Fair Value Measurement [Member] | Recurring [Member]
Assets:
Restricted cash	551	$ 180
Total assets	35,949	4,481
Liabilities:
Derivative liability	1,010	2,425
Total Liabilities	1,010	2,425
Estimate of Fair Value Measurement [Member] | Recurring [Member] | Money Market Funds [Member]
Assets:
Cash equivalents		4,301
Estimate of Fair Value Measurement [Member] | Recurring [Member] | Certificates of Deposit [Member]
Assets:
Assets, fair value	1,251
Estimate of Fair Value Measurement [Member] | Recurring [Member] | U.S. Treasury Securities [Member]
Assets:
Assets, fair value	34,147
Estimate of Fair Value Measurement [Member] | Level 1 [Member] | Recurring [Member]
Assets:
Restricted cash	551	180
Total assets	34,698	4,481
Estimate of Fair Value Measurement [Member] | Level 1 [Member] | Recurring [Member] | Money Market Funds [Member]
Assets:
Cash equivalents		4,301
Estimate of Fair Value Measurement [Member] | Level 1 [Member] | Recurring [Member] | U.S. Treasury Securities [Member]
Assets:
Assets, fair value	34,147
Estimate of Fair Value Measurement [Member] | Level 2 [Member] | Recurring [Member]
Assets:
Total assets	1,251
Estimate of Fair Value Measurement [Member] | Level 2 [Member] | Recurring [Member] | Certificates of Deposit [Member]
Assets:
Assets, fair value	1,251
Estimate of Fair Value Measurement [Member] | Level 3 [Member] | Recurring [Member]
Liabilities:
Derivative liability	1,010	2,425
Total Liabilities	$ 1,010	$ 2,425

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability, current		$ 2,425
Derivative liability, noncurrent	$ 1,010
CRG [Member] | Term Loan Agreement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability, current		2,400
Derivative liability, noncurrent	1,000
Money Market Accounts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash	$ 600
Certificates of deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash		$ 200

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Contingent Interest Payments (Detail) - CRG [Member] - Term Loan Agreement [Member] - Measurement Input, Discount Rate [Member]	12 Months Ended
	Dec. 31, 2020
Contingent Interest Beginning in 2021 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
4% contingent interest beginning, Range	0.00%
Contingent Interest Beginning in 2022 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
4% contingent interest beginning, Range	90.00%

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Contingent Interest Payments (Parenthetical) (Detail) - CRG [Member] - Term Loan Agreement [Member]	12 Months Ended
	Dec. 31, 2020
Contingent Interest Beginning in 2021 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent payment of interest rate	4.00%
Contingent Interest Beginning in 2022 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent payment of interest rate	4.00%

Fair Value Measurements - Roll-

Fair Value Measurements - Roll-Forward of Fair Value of Derivative Liability (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of derivative liability, recorded as interest expense	$ (1,415)	$ 283
Probability-Weighted Discounted Cash Flow Model [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance	2,425	2,142
Change in fair value of derivative liability, recorded as interest expense	(1,415)	283
Ending balance	$ 1,010	$ 2,425

Restricted Cash - Additional In

Restricted Cash - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)Facility	Dec. 31, 2019USD ($)
Money Market Accounts [Member]
Restricted Cash And Cash Equivalents Items [Line Items]
Security deposits	$ 0.6
Number of facilities | Facility	2
Certificates of deposit [Member]
Restricted Cash And Cash Equivalents Items [Line Items]
Security deposits		$ 0.2

Supplemental Balance Sheet In_3

Supplemental Balance Sheet Information - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 18,028	$ 19,081
Less accumulated depreciation and amortization	(14,257)	(13,236)
Property and equipment, net	$ 3,771	5,845
Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	3 years
Property and equipment, gross	$ 538	538
Software [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	3 years
Property and equipment, gross	$ 762	762
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Property and equipment, gross	$ 5,179	4,747
Furniture [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 197	194
Furniture [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Furniture [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	7 years
Manufacturing Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Property and equipment, gross	$ 672	672
Manufacturing Tooling and Molds [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 255	255
Manufacturing Tooling and Molds [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	6 months
Manufacturing Tooling and Molds [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	5 years
T2-Owned Instruments and Components [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Property and equipment, gross	$ 5,001	6,775
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,691	3,497
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,733	$ 1,641

Supplemental Balance Sheet In_4

Supplemental Balance Sheet Information - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Supplemental Balance Sheet Information [Line Items]
Raw materials and work-in-process inventory	$ 300	$ 600
Depreciation and amortization	1,710	2,197
Accrued final fee		2,445
Accrued final fee noncurrent	3,400
Other accrued expenses	620	1,900
Accrued payroll and compensation	3,629	3,193
Transition Agreement [Member]
Supplemental Balance Sheet Information [Line Items]
Other accrued expenses	$ 200	1,000
Accrued payroll and compensation		200
T2 Owned Instruments in Service [Member]
Supplemental Balance Sheet Information [Line Items]
Estimated useful lives (in years)	5 years
T2 Owned Instruments in Service [Member] | Product [Member]
Supplemental Balance Sheet Information [Line Items]
Depreciation expense recorded as a component of cost of product revenue	$ 300	$ 800
T2-Owned Instruments and Components [Member]
Supplemental Balance Sheet Information [Line Items]
Estimated useful lives (in years)	5 years
T2-Owned Instruments and Components [Member] | COVID-19 [Member]
Supplemental Balance Sheet Information [Line Items]
Decrease in carrying value of property and equipment	$ 600

Supplemental Balance Sheet In_5

Supplemental Balance Sheet Information - Components of Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued Liabilities Current [Abstract]
Accrued payroll and compensation	$ 3,629	$ 3,193
Accrued final fee		2,445
Accrued research and development expenses	751	267
Accrued professional services	421	511
Accrued interest	940	908
Operating lease liabilities	1,151	1,983
Other accrued expenses	620	1,900
Total accrued expenses and other current liabilities	$ 7,512	$ 11,207

Notes Payable - Schedule of Deb

Notes Payable - Schedule of Debt (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Debt Disclosure [Abstract]
2022	$ 48,077
Total before unamortized discount and issuance costs	48,077
Less: paid-in-kind interest	(1,669)
Less: unamortized discount and issuance costs	(1,173)
Total notes payable	$ 45,235

Notes Payable - Term Loan Agree

Notes Payable - Term Loan Agreement - Additional Information (Detail) - USD ($)	1 Months Ended			9 Months Ended	12 Months Ended	24 Months Ended
	Sep. 30, 2019	Mar. 31, 2019	Dec. 31, 2016	Dec. 31, 2022	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Common Stock [Member]
Debt Instrument
Number of shares issuable for warrants outstanding (in shares)	568,291		528,958
Exercise price of warrants	$ 1.55	$ 4.35	$ 8.06
CRG [Member] | Term Loan Agreement [Member]
Debt Instrument
Debt maturity date					Dec. 31, 2022
Proceeds from issuance of long-term debt			$ 40,000,000
Debt term (in years)			6 years
Debt instrument, term of interest-only payments (in years)			4 years
Final fee as a percentage of the principal outstanding (as a percent)	10.00%		8.00%		10.00%		10.00%
Annual fixed rate (as a percent)			11.50%
Deferred interest rate (as a percent)			3.50%
Debt instrument, prepayment fee term (in years)			5 years
Debt instrument covenant compliance revenue target	$ 4,000,000	$ 9,000,000					$ 95,000,000
Additional interest rate, event of default (as a percent)					4.00%
CRG [Member] | Term Loan Agreement [Member] | Scenario Forecast [Member]
Debt Instrument
Debt instrument, quarterly principal payment				$ 12,000,000
Debt instrument covenant compliance revenue target						$ 140,000,000
CRG [Member] | Term Loan Agreement, Amended [Member]
Debt Instrument
Debt instrument covenant compliance revenue target							$ 15,000,000
CRG [Member] | Term Loan Agreement, Amended [Member] | Scenario Forecast [Member]
Debt Instrument
Debt instrument covenant compliance revenue target						$ 43,000,000

Notes Payable - Equipment Lease

Notes Payable - Equipment Lease Credit Facility - Additional Information (Detail) - Finance Lease Obligations [Member]	1 Months Ended			12 Months Ended
	Jun. 30, 2016USD ($)Draw	Apr. 30, 2016USD ($)	Oct. 31, 2015USD ($)	Dec. 31, 2019USD ($)
Debt Instrument
Initial borrowing capacity			$ 10,000,000
Maximum borrowings available (up to)			$ 5,000,000
Debt term (in months)			36 months
Repurchase price as percentage of original equipment value that the equipment under lease may be repurchased by lessee			10.00%
Minimum lease period to extend lease (in years)			1 year
Amount of draw	$ 2,500,000	$ 2,100,000
Amount of monthly payment	$ 79,000	$ 67,000
Number of draws | Draw	2
Repurchase of equipment				$ 300,000

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit) - Additional Information (Detail)	Apr. 08, 2020USD ($)	Apr. 07, 2020	Mar. 09, 2020USD ($)	Jul. 30, 2019USD ($)	Jul. 29, 2019USD ($)shares	Dec. 31, 2020USD ($)Item$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares
Class Of Stock [Line Items]
Number of voting rights per share of common stock | Item						1
Common stock, par value (in dollars per share) | $ / shares						$ 0.001	$ 0.001
Common stock, shares authorized						200,000,000	200,000,000
Common stock, shares outstanding						148,078,974	50,651,535
Lincoln Park [Member]
Class Of Stock [Line Items]
Purchase agreement termination effective date		Apr. 8, 2020
Sales Agreement [Member] | Canaccord [Member]
Class Of Stock [Line Items]
Sale of common stock authorized, amount | $	$ 95,000,000		$ 65,000,000	$ 30,000,000
Number of shares issued/sold						96,120,167	5,486,500
Percentage of agent service fee				3.00%
Proceeds from issuance of common stock | $						$ 85,000,000	$ 6,700,000
Equity Distribution Agreement [Member] | Canaccord [Member]
Class Of Stock [Line Items]
Number of shares issued/sold						101,606,667
Aggregate gross sales amount of common stock | $						$ 95,000,000
Purchase Agreement [Member] | Lincoln Park [Member]
Class Of Stock [Line Items]
Sale of common stock authorized, amount | $					$ 30,000,000
Number of shares issued/sold					413,349	400,000
Proceeds from issuance of common stock | $						$ 300,000
Effective period for sale of common stock					36 months
Maximum number of shares issue per business day					200,000
Maximum amount of shares to be issue per business day | $					$ 2,000,000
Options to Purchase Common Shares [Member]
Class Of Stock [Line Items]
Common stock reserved for issuance						8,595,929
Issuance of Stock Awards [Member]
Class Of Stock [Line Items]
Common stock reserved for issuance						1,643,779
Exercise of Warrants [Member]
Class Of Stock [Line Items]
Common stock reserved for issuance						1,097,249

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 06, 2020	Mar. 31, 2018
Share-Based Compensation
Fair value of vested stock options	$ 3,500,000	$ 3,100,000
Stock-based compensation expense	$ 3,899,000	5,437,000
Employee Stock Purchase Plan [Member]
Share-Based Compensation
Shares available for grant	3,268,850
Shares available for authorization				4,523,944
Percentage of full share price paid in purchase of common stock	85.00%
Maximum amount of annual employee common stock purchases	$ 25,000
Stock-based compensation expense	$ 300,000	400,000
Number of shares purchased by participants	453,104
Restricted Stock Units [Member]
Share-Based Compensation
Weighted-average period	1 year 7 months 6 days
Unrecognized compensation cost related to unvested stock options	$ 1,200,000
2014 Stock Option Plan [Member] | Stock Options [Member]
Share-Based Compensation
Shares available for future issuance under stock incentive plan	823,529
Percentage of common shares outstanding	4.00%
Shares available for grant	2,237,168
2014 Stock Option Plan [Member] | Restricted Stock Units [Member]
Share-Based Compensation
Restricted stock units vested	331,433
Restricted stock units granted	1,380,923
Inducement Award Plan [Member]
Share-Based Compensation
Shares available for grant	2,073,281
Shares available for authorization					5,625,000
2006 and 2014 Stock Option Plans [Member] | Stock Options [Member]
Share-Based Compensation
Aggregate fair value of options granted	$ 3,300,000	$ 3,900,000
Unrecognized compensation cost related to non-vested stock options	$ 4,100,000
Weighted-average period	2 years 4 months 24 days
2006 and 2014 Stock Option Plans and Inducement Plan [Member] | Stock Options [Member]
Share-Based Compensation
Issuance of common stock from exercise of stock options (in shares)	49,563	2,119
Weighted average fair value of options granted	$ 0.71	$ 1.41
2006 and 2014 Stock Option Plans and Inducement Plan [Member] | Restricted Stock Units [Member]
Share-Based Compensation
Aggregate fair value of restricted stock units granted	$ 1,200,000
2006 and 2014 Stock Option Plans and Inducement Plan [Member] | Restricted Stock Units [Member] | Restricted Stock Units Vested, Not Reflected As Outstanding Shares [Member]
Share-Based Compensation
Restricted stock units vested			73,172
2006 and 2014 Stock Option Plans and Inducement Plan [Member] | Restricted Stock Units with Market Condition [Member]
Share-Based Compensation
Restricted stock units granted	318,898
Compensation Cost		$ 1,000,000
Maximum [Member] | 2006 Stock Option Plan [Member] | Stock Options [Member]
Share-Based Compensation
Expiration period	10 years
Vesting period	4 years
Maximum [Member] | 2014 Stock Option Plan [Member] | Stock Options [Member]
Share-Based Compensation
Expiration period	10 years
Vesting period	4 years

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - 2006 and 2014 Stock Option Plans and Inducement Plan [Member] - Stock Options [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-Based Compensation
Number of Shares Outstanding, beginning of the period	6,353,330
Number of Shares, Granted	4,306,750
Number of Shares, Exercised	(49,563)	(2,119)
Number of Shares, Forfeited	(1,232,700)
Number of Shares, Canceled	(781,888)
Number of Shares Outstanding, end of the period	8,595,929	6,353,330
Number of Shares, Exercisable	4,098,314
Number of Shares, Vested or expected to vest	7,650,363
Weighted-Average Exercise Price Per Share Outstanding, beginning of the period	$ 4.95
Weighted-Average Exercise Price Per Share, Granted	1.02
Weighted-Average Exercise Price Per Share, Exercised	0.61
Weighted-Average Exercise Price Per Share, Forfeited	3.04
Weighted-Average Exercise Price Per Share, Canceled	5.43
Weighted-Average Exercise Price Per Share Outstanding, end of the period	3.24	$ 4.95
Weighted-Average Exercise Price Per Share, Exercisable	4.98
Weighted-Average Exercise Price Per Share, Vested or expected to vest	$ 3.46
Weighted-Average Remaining Contractual Term, Outstanding	7 years 9 months	7 years 3 months 14 days
Weighted-Average Remaining Contractual Term, Exercisable	6 years 6 months 25 days
Weighted-Average Remaining Contractual Term, Vested or expected to vest	7 years 7 months 9 days
Aggregate Intrinsic Value, Outstanding, beginning of the period	$ 229
Aggregate Intrinsic Value, Exercised	33
Aggregate Intrinsic Value Outstanding, end of the period	1,011	$ 229
Aggregate Intrinsic Value, Exercisable	272
Aggregate Intrinsic Value, Vested or expected to vest	$ 845

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Estimated Assumptions Used to Calculate Weighted-Average Grant Date Fair Value of Options Granted (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-Based Compensation
Expected dividend yield	0.00%
Stock Options [Member] | 2006 and 2014 Stock Option Plans and Inducement Plan [Member]
Share-Based Compensation
Weighted-average risk-free interest rate	1.35%	1.97%
Expected dividend yield	0.00%	0.00%
Expected volatility	92.00%	78.00%
Expected terms	5 years 9 months 18 days	6 years

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Nonvested Restricted Stock Units Activity (Detail) - 2014 Stock Option Plan [Member] - Restricted Stock Units [Member]	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Share-Based Compensation
Number of Shares, Nonvested restricted shares at the beginning of the period | shares	1,295,508
Number of Shares, Restricted shares granted | shares	1,380,923
Number of Shares, Restricted shares vested | shares	(331,433)
Number of Shares, Restricted shares forfeited | shares	(701,219)
Number of Shares, Canceled | shares	0
Number of Shares, Nonvested restricted shares at the end of the period | shares	1,643,779
Weighted-Average Grant Date Fair Value, Nonvested restricted shares at the beginning of the period | $ / shares	$ 4.19
Weighted-Average Grant Date Fair Value, Granted | $ / shares	0.89
Weighted-Average Grant Date Fair Value, Vested | $ / shares	3.45
Weighted-Average Grant Date Fair Value, Forfeited | $ / shares	3.37
Weighted-Average Grant Date Fair Value, Canceled | $ / shares	0
Weighted-Average Grant Date Fair Value, Nonvested restricted shares at the end of the period | $ / shares	$ 1.91

Stock-Based Compensation - Sc_3

Stock-Based Compensation - Schedule of Estimated Assumptions Used to Calculate Weighted-Average Fair Value of the Purchase Rights Granted (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-Based Compensation
Expected dividend yield	0.00%
Employee Stock Purchase Plan [Member]
Share-Based Compensation
Weighted-average risk-free interest rate	1.59%	2.44%
Expected dividend yield	0.00%	0.00%
Expected volatility	92.00%	71.00%
Expected terms	6 months	6 months

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock-Based Compensation Expense for Stock Options Granted that was Recorded in the Company's Results of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Stock-based compensation expense
Stock-based compensation expense	$ 3,899	$ 5,437
Cost of Product Revenue [Member]
Stock-based compensation expense
Stock-based compensation expense	221	365
Research and Development [Member]
Stock-based compensation expense
Stock-based compensation expense	777	1,184
Selling, General and Administrative [Member]
Stock-based compensation expense
Stock-based compensation expense	$ 2,901	$ 3,888

Warrants - Additional Informati

Warrants - Additional Information (Detail) - Common Stock [Member] - USD ($) $ / shares in Units, $ in Millions	1 Months Ended
	Sep. 30, 2019	Mar. 31, 2019	Dec. 31, 2016
Class of Warrant or Right [Line Items]
Number of shares issuable for warrants outstanding	568,291		528,958
Exercise price of warrants	$ 1.55	$ 4.35	$ 8.06
Fair market value of amended warrants	$ 0.1	$ 0.9
Incremental fair value of warrants adjustment	$ 0.7	$ 0.1

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Share Applicable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss	$ (46,798)	$ (59,006)
Denominator:
Weighted-average number of common shares outstanding — basic and diluted	121,331,464	45,507,754
Net loss per share — basic and diluted	$ (0.39)	$ (1.30)

Net Loss Per Share - Schedule_2

Net Loss Per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted net loss per share	11,336,957	8,746,087
Options to Purchase Common Shares [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted net loss per share	8,595,929	6,353,330
Restricted Stock Units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted net loss per share	1,643,779	1,295,508
Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted net loss per share	1,097,249	1,097,249

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of the U.S. Federal Statutory Rate to the Company's Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Percent.
Tax at statutory rates	21.00%	21.00%
State income taxes	6.40%	2.60%
Permanent differences	(1.90%)	(1.20%)
Research and development credits	1.40%	1.00%
Limitations on credits and net operating losses	0.10%	(75.20%)
Change in valuation allowance	(27.00%)	51.80%
Effective tax rate	0.00%	0.00%

Income Taxes - Schedule Of Defe

Income Taxes - Schedule Of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating loss carryforwards	$ 61,551	$ 50,407
Tax credits	1,428	472
Other temporary differences	3,546	2,888
Start-up expenditures	2,672	2,716
Stock option expenses	3,382	3,450
Lease liability	3,170	987
Total deferred tax assets	75,749	60,920
Deferred tax asset valuation allowance	(72,404)	(59,764)
Net deferred tax assets	3,345	1,156
Deferred tax liabilities:
Right of use asset	(2,994)	(859)
Prepaid expenses	$ (351)	$ (297)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Line Items]
Increase (decrease) in valuation allowance	$ 12,600	$ (30,600)
Unrecognized tax benefits	0
Accrued interest or penalties related to uncertain tax positions	0	0
Federal [Member]
Income Taxes [Line Items]
Net operating losses	222,600	329,600
Net operating loss carryforwards, subject to expiration	$ 78,700
Net operating loss carryforwards, expiration date	2037
Net operating loss carryforwards, not subject to expiration	$ 143,900
Credit carryforward		5,500
Federal [Member] | Internal Revenue Code [Member]
Income Taxes [Line Items]
Net operating losses		149,500
Credit carryforward		5,400
Federal [Member] | Research and Development [Member]
Income Taxes [Line Items]
Credit carryforward	$ 800
Credit carryforward, expiration date	2040
State [Member]
Income Taxes [Line Items]
Net operating losses	$ 247,900	292,400
Net operating loss carryforwards, subject to expiration	$ 215,300
Net operating loss carryforwards, expiration date	2040
Net operating loss carryforwards, not subject to expiration	$ 32,600
Credit carryforward		3,600
State [Member] | Internal Revenue Code [Member]
Income Taxes [Line Items]
Net operating losses		78,900
Credit carryforward		$ 3,200
State [Member] | Research and Development [Member]
Income Taxes [Line Items]
Credit carryforward	$ 800
Credit carryforward, expiration date	2035

Leases - Additional Information

Leases - Additional Information (Detail)

1 Months Ended

12 Months Ended

Oct. 31, 2020

Jun. 30, 2020USD ($)

Aug. 31, 2018

Sep. 30, 2017

Mar. 31, 2017

Jun. 30, 2016USD ($)Draw

Apr. 30, 2016USD ($)

Oct. 31, 2015USD ($)

Apr. 30, 2015

Nov. 30, 2014USD ($)

Dec. 31, 2020USD ($)

Dec. 31, 2019USD ($)

Jan. 31, 2018USD ($)

Jan. 01, 2011USD ($)

Leases [Line Items]

Right-of-use assets

$ 11,034,000

$ 3,360,000

Lease liabilities

11,684,000

3,856,000

Impairment of operating lease asset

523,000

0

Finance Lease Obligations [Member]

Leases [Line Items]

Initial borrowing capacity

$ 10,000,000

Maximum borrowings available (up to)

$ 5,000,000

Debt term (in months)

36 months

Repurchase price as percentage of original equipment value that the equipment under lease may be repurchased by lessee

10.00%

Minimum lease period to extend lease (in years)

1 year

Amount of draw

$ 2,500,000

$ 2,100,000

Amount of monthly payment

$ 79,000

$ 67,000

Number of draws | Draw

2

Repurchase of equipment

$ 300,000

Operating Lease Entered into November 2014 [Member] | License Agreement [Member] | Office Space [Member]

Leases [Line Items]

Lease expiration date

Dec. 31, 2021

Dec. 31, 2017

Security deposits

$ 50,000

Operating Lease Entered into November 2014 [Member] | License Agreement [Member] | Office Space [Member] | Selling, General and Administrative [Member] | COVID-19 [Member]

Leases [Line Items]

Impairment of operating lease asset

$ 500,000

Office Space, Laboratory Space, and Equipment [Member]

Leases [Line Items]

Right-of-use assets

0

Lease liabilities

$ 0

Maximum lease period to not recognize right of use assets or lease liabilities

12 months

Office and Laboratory Space [Member] | Operating Lease Entered into August 2010 [Member]

Leases [Line Items]

Right-of-use assets

$ 7,600,000

Lease liabilities

7,700,000

Lease expiration month year

2021-12

Lease expiration date

Dec. 31, 2028

Security deposits

420,438

$ 180,000

$ 400,000

Office, Laboratory and Manufacturing Space [Member] | Operating Lease Entered into May 2013 [Member]

Leases [Line Items]

Right-of-use assets

200,000

Lease liabilities

200,000

Lease expiration month year

2020-12

Lease expiration date

Dec. 31, 2022

Laboratory Space [Member] | Operating Lease Entered into November 2014 [Member]

Leases [Line Items]

Right-of-use assets

1,800,000

Lease liabilities

1,900,000

Lease expiration date

Oct. 31, 2025

Security deposits

$ 281,000

130,977

Term of lease

6 years

Space build-out costs paid

$ 1,400,000

Space build-out costs

$ 2,200,000

Security deposit received from landlord

$ 281,000

Leases - Schedule of Lease Cost

Leases - Schedule of Lease Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finance lease cost:
Amortization of right-of-use assets		$ 235
Interest on lease liabilities		36
Operating lease cost	$ 1,945	1,995
Variable lease cost	754	659
Total lease cost	$ 2,699	$ 2,925

Leases - Schedule of Other Info

Leases - Schedule of Other Information Related to Leases (Detail)	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Weighted-average remaining lease term - operating leases (in years)	7 years 1 month 6 days	1 year 10 months 24 days
Weighted-average discount rate - operating leases	11.90%	11.90%

Leases - Schedule of Maturity o

Leases - Schedule of Maturity of Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Maturity of operating leases liabilities
2021	$ 2,440
2022	2,345
2023	2,290
2024	2,358
2025	2,331
Thereafter	5,851
Total lease payments	17,615
Less: effect of discounting	(5,931)
Present value of lease liabilities	$ 11,684	$ 3,856

Leases - Summary of Lease Asset

Leases - Summary of Lease Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Lease Assets And Liabilities [Abstract]
Operating lease assets	$ 11,034	$ 3,360
Operating lease liabilities, Current	$ 1,151	$ 1,983
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses and other current liabilities	Accrued expenses and other current liabilities
Operating lease liabilities, Noncurrent	$ 10,533	$ 1,873
Total lease liabilities	$ 11,684	$ 3,856

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	12 Months Ended	24 Months Ended
	Dec. 31, 2020	Dec. 31, 2007	Dec. 31, 2019	Dec. 31, 2006
Commitments and Contingencies [Line Items]
Accrued payroll and compensation	$ 3,629,000		$ 3,193,000
License Agreement [Member]
Commitments and Contingencies [Line Items]
Shares issued		84,678
Royalty on net sales sublicensing gross revenue	10.00%
Royalties due	$ 100,000
Transition Agreement [Member]
Commitments and Contingencies [Line Items]
Payment period on transition and health benefits	15 months
Transition Agreement [Member] | Accrued Expenses [Member]
Commitments and Contingencies [Line Items]
Transition payments and health benefits	$ 200,000		$ 1,200,000
Minimum [Member] | License Agreement [Member]
Commitments and Contingencies [Line Items]
Annual license fee payable				$ 5,000
Percentage of royalty on net sales	0.50%
Maximum [Member] | License Agreement [Member]
Commitments and Contingencies [Line Items]
Annual license fee payable				$ 25,000
Percentage of royalty on net sales	3.50%

401(k) Savings Plan - Additiona

401(k) Savings Plan - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Compensation And Retirement Disclosure [Abstract]
Contributions to 401 (k) plan at the discretion of the board	$ 163,000	$ 195,000

Co-Development Agreements - Add

Co-Development Agreements - Additional Information (Detail)	Sep. 21, 2016USD ($)	Feb. 03, 2015USD ($)Item	Sep. 30, 2020USD ($)	Jan. 31, 2019USD ($)	May 31, 2018USD ($)	Mar. 31, 2018USD ($)specie	Oct. 31, 2015USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue								$ 18,130,000	$ 8,335,000
Contribution [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue								6,442,000	2,445,000
Co Development Partnership Agreement [Member] | Canon U.S. Life Sciences Inc [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment		$ 2,000,000
Additional consideration receivable upon achievement of certain development and regulatory milestones		6,500,000
Aggregate consideration receivable		$ 8,500,000
Proceeds received for achievement of milestone					$ 2,000,000		$ 1,500,000
Final regulatory milestone will not achieve									3,000,000
Number of units | Item		1
Revenue								0	500,000
Co Development Partnership Agreement [Member] | CARB-X [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue								0	900,000
Number of additional bacteria species added to existing product candidate | specie						20
Co Development Partnership Agreement [Member] | CARB-X [Member] | Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate consideration receivable						$ 2,000,000
Collaborative arrangement reimbursement amount				$ 900,000		1,100,000
Milestone payment						$ 900,000
Co Development Partnership Agreement [Member] | Biomedical Advanced Research and Development Authority [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Initial value of consideration receivable										$ 6,000,000
Co Development Partnership Agreement [Member] | Biomedical Advanced Research and Development Authority [Member] | Contribution [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue								$ 6,400,000	$ 1,500,000
Co Development Partnership Agreement [Member] | Biomedical Advanced Research and Development Authority [Member] | Initial Award [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
First contract option value exercised			$ 10,500,000
Co Development Partnership Agreement [Member] | Biomedical Advanced Research and Development Authority [Member] | Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate consideration receivable										$ 69,000,000
Private Placement [Member] | Canon U S A Inc [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceeds from sale of shares in related party	$ 39,700,000
Percentage of outstanding shares at date of sale	19.90%