TELA Bio (TELA) 10-K 22 Mar 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Mar. 14, 2024	Jun. 30, 2023
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	001-39130
Entity Registrant Name	TELA Bio, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-5320061
Entity Address, Address Line One	1 Great Valley Parkway, Suite 24
Entity Address, City or Town	Malvern
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19355
City Area Code	484
Local Phone Number	320-2930
Title of 12(b) Security	Common Stock, $0.001 par value per share
Trading Symbol	TELA
Security Exchange Name	NASDAQ
Entity Well Known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 245.3
Entity Common Stock, Shares Outstanding		24,649,595
Entity Central Index Key	0001561921
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Auditor Name	KPMG LLP
Auditor Firm ID	185
Auditor Location	Philadelphia, PA

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 46,729	$ 42,019
Accounts receivable, net of allowances of $416 and $143	9,737	6,621
Inventory	13,162	11,792
Prepaid expenses and other assets	2,098	2,015
Total current assets	71,726	62,447
Property and equipment, net	1,984	1,682
Intangible assets, net	2,119	2,499
Right-of-use assets	1,954	1,227
Restricted cash	265
Total assets	78,048	67,855
Current liabilities:
Accounts payable	1,667	1,534
Accrued expenses and other current liabilities	15,300	10,869
Total current liabilities	16,967	12,403
Long-term debt	40,515	39,916
Other long-term liabilities	1,685	1,231
Total liabilities	59,167	53,550
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock; $0.001 par value: 10,000,000 shares authorized; no shares issued and outstanding
Common stock; $0.001 par value: 200,000,000 shares authorized; 24,494,675 and 19,165,027 shares issued and outstanding at December 31, 2023 and December 31, 2022, respectively	24	19
Additional paid-in capital	339,655	288,361
Accumulated other comprehensive income	91	150
Accumulated deficit	(320,889)	(274,225)
Total stockholders' equity	18,881	14,305
Total liabilities and stockholders' equity	$ 78,048	$ 67,855

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Consolidated Balance Sheets
Accounts receivable, Allowance	$ 416	$ 143
Preferred stock, Par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, Par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	24,494,675	19,165,027
Common stock, shares outstanding (in shares)	24,494,675	19,165,027

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Consolidated Statements of Operations and Comprehensive Loss
Revenue	$ 58,453	$ 41,418	$ 29,463
Cost of revenue (excluding amortization of intangible assets)	17,961	13,570	10,346
Amortization of intangible assets	380	804	304
Gross profit	40,112	27,044	18,813
Operating expenses:
Sales and marketing	59,681	43,252	29,062
General and administrative	14,887	13,862	12,459
Research and development	9,619	8,937	6,743
Total operating expenses	84,187	66,051	48,264
Loss from operations	(44,075)	(39,007)	(29,451)
Other expense:
Interest expense	(5,223)	(4,051)	(3,597)
Loss on extinguishment of debt		(1,228)
Other income (expense)	2,634	(10)	(228)
Total other expense	(2,589)	(5,289)	(3,825)
Net loss	$ (46,664)	$ (44,296)	$ (33,276)
Net loss per common share, basic	$ (2.04)	$ (2.72)	$ (2.30)
Net loss per common share, diluted	$ (2.04)	$ (2.72)	$ (2.30)
Weighted average common shares outstanding, basic	22,868,663	16,267,678	14,473,213
Weighted average common shares outstanding, diluted	22,868,663	16,267,678	14,473,213
Comprehensive loss:
Net loss	$ (46,664)	$ (44,296)	$ (33,276)
Foreign currency translation adjustment	(59)	202	19
Comprehensive loss	$ (46,723)	$ (44,094)	$ (33,257)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common stock	Additional paid-in capital	Accumulated other comprehensive income	Accumulated deficit	Total
Balance at Beginning of period at Dec. 31, 2020	$ 14	$ 245,736	$ (71)	$ (196,653)	$ 49,026
Balance at Beginning of period (in shares) at Dec. 31, 2020	14,437,107
Vesting of common stock previously subject to repurchase		1			1
Vesting of common stock previously subject to repurchase (in shares)	153
Vesting of share-based awards and exercise of stock options	$ 1	546			$ 547
Vesting of share-based awards and exercise of stock options (in shares)	89,154				77,154
Issuance of common stock under the employee stock purchase plan		38			$ 38
Issuance of common stock under the employee stock purchase plan (in shares)	3,163
Foreign currency translation adjustment			19		19
Stock-based compensation expense		3,661			3,661
Sale of common stock, net of underwriting discounts, commissions and offering costs		82			82
Net loss				(33,276)	(33,276)
Balance at Ending period at Dec. 31, 2021	$ 15	250,064	(52)	(229,929)	20,098
Balance at Ending period (in shares) at Dec. 31, 2021	14,529,577
Vesting of common stock previously subject to repurchase (in shares)	29
Vesting of share-based awards and exercise of stock options		19			$ 19
Vesting of share-based awards and exercise of stock options (in shares)	44,346				3,563
Issuance of common stock under the employee stock purchase plan		50			$ 50
Issuance of common stock under the employee stock purchase plan (in shares)	4,523
Shares withheld for employee taxes		(157)			(157)
Shares withheld for employee taxes (in shares)	(13,448)
Foreign currency translation adjustment			202		202
Stock-based compensation expense		3,989			3,989
Reclassification of liability-classified stock-based compensation awards	$ 4	34,396			34,400
Sale of common stock, net of underwriting discounts, commissions and offering costs (in shares)	4,600,000
Net loss				(44,296)	(44,296)
Balance at Ending period at Dec. 31, 2022	$ 19	288,361	150	(274,225)	14,305
Balance at Ending period (in shares) at Dec. 31, 2022	19,165,027
Vesting of share-based awards and exercise of stock options		127			$ 127
Vesting of share-based awards and exercise of stock options (in shares)	126,987				25,428
Issuance of common stock under the employee stock purchase plan		88			$ 88
Issuance of common stock under the employee stock purchase plan (in shares)	10,602
Shares withheld for employee taxes		(289)			(289)
Shares withheld for employee taxes (in shares)	(27,131)
Foreign currency translation adjustment			(59)		(59)
Stock-based compensation expense		5,032			5,032
Sale of common stock, net of underwriting discounts, commissions and offering costs	$ 5	46,336			46,341
Sale of common stock, net of underwriting discounts, commissions and offering costs (in shares)	5,219,190
Net loss				(46,664)	(46,664)
Balance at Ending period at Dec. 31, 2023	$ 24	$ 339,655	$ 91	$ (320,889)	$ 18,881
Balance at Ending period (in shares) at Dec. 31, 2023	24,494,675

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (46,664)	$ (44,296)	$ (33,276)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	428	383	231
Noncash interest expense	599	657	664
Noncash loss on extinguishment of debt		1,228
Amortization of intangible assets	380	804	304
Net changes in operating lease ROU assets and liabilities	(49)	(36)
Inventory excess and obsolescence charge	1,414	1,866	1,439
Stock-based compensation expense	5,032	3,989	3,661
(Gain) loss on disposal of fixed assets	(12)		2
Change in operating assets and liabilities:
Accounts receivable, net	(3,058)	(2,421)	(1,553)
Inventory	(2,718)	(6,073)	(5,194)
Prepaid expenses and other current assets	(81)	1,216	(992)
Accounts payable	11	(884)	1,597
Accrued expenses and other current and long-term liabilities	4,177	2,399	2,673
Foreign currency translation (gain) loss	(316)	420	12
Net cash used in operating activities	(40,857)	(40,748)	(30,432)
Cash flows from investing activities:
Payment for intangible asset		(1,000)
Purchase of property and equipment	(611)	(872)	(627)
Proceeds from the sale property and equipment	12
Net cash used in investing activities	(599)	(1,872)	(627)
Cash flows from financing activities:
Proceeds from sale of common stock, net of underwriting discounts, commissions and offering costs	46,341	34,400
Proceeds from issuance of long-term debt		40,000
Repayment of long-term debt		(30,000)
Payment of debt financing costs		(3,460)
Proceeds from exercise of stock options	127	19	547
Payment of withholding taxes related to stock-based compensation to employees	(289)	(157)
Proceeds from issuance of common stock under the employee stock purchase plan	88	50	38
Net cash provided by financing activities	46,267	40,852	585
Effect of exchange rate on cash and cash equivalents	164	(144)	11
Net increase (decrease) in cash and cash equivalents and restricted cash	4,975	(1,912)	(30,463)
Cash and cash equivalents and restricted cash, beginning of year	42,019	43,931	74,394
Cash and cash equivalents and restricted cash, end of year	46,994	42,019	43,931
Supplemental disclosure of cash flow information:
Cash paid during the period for interest	4,624	3,394	2,933
Supplemental disclosures of noncash investing and financing activities:
Property and equipment in accounts payable and accrued expenses and other current liabilities	119	7	166
Issuance of common stock for early exercised stock options			1
Reclassification of liability-classified stock-based compensation awards to equity-classified			$ 82
Operating lease ROU asset exchanged for operating lease liabilities	$ 895	1,376
Tenant improvement and deferred rent reclassified to operating lease liabilities		380
Operating lease liabilities assumed for operating lease ROU assets		$ 1,756

Background

Background	12 Months Ended
	Dec. 31, 2023
Background
Background	(1) Background TELA Bio, Inc. (the “Company”) was incorporated in the state of Delaware on April 17, 2012 and wholly owns TELA Bio Limited, a company incorporated in the United Kingdom. The Company is a commercial-stage medical technology company focused on providing innovative soft-tissue reconstruction solutions that optimize clinical outcomes by prioritizing the preservation and restoration of the patient’s own anatomy. OviTex Reinforced Tissue Matrix (“OviTex”), the Company’s first portfolio of products, addresses unmet needs in hernia repair and abdominal wall reconstruction by combining the benefits of biologic matrices and polymer materials while minimizing their shortcomings, at a cost-effective price. OviTex PRS Reinforced Tissue Matrix (“OviTex PRS”), the Company’s second portfolio of products, addresses unmet needs in plastic and reconstructive surgery. The Company’s principal corporate office and research facility is located in Malvern, Pennsylvania. The Company has been directly impacted by the COVID-19 pandemic since the onset of the pandemic in 2020. To date, among other impacts on the Company’s business related to the pandemic, physicians and their patients have been required by state mandates, or have chosen to, defer elective surgery procedures in which the Company’s products otherwise would be used. There remains some uncertainty regarding the lingering effects of the COVID-19 pandemic on the Company’s near-term revenue growth prospects and product development plans due to the volatility in the frequency of surgical procedures using the Company’s products, including through labor and hospital staffing shortages and the allocation of hospital resources due to financial strain experienced during the COVID-19 pandemic. While the Company believes that surgical procedures have started to normalize to pre-pandemic levels and that hospital systems have begun to address any remaining backlog of procedures previously delayed due to the COVID-19 pandemic, the full extent of the impact of the COVID-19 pandemic on the Company’s business, results of operations and financial condition, including revenue, expenses, manufacturing capability, supply chain integrity, staffing availability, research and development costs and employee-related compensation, will depend on future developments that remain uncertain.

Risks and Liquidity

Risks and Liquidity	12 Months Ended
	Dec. 31, 2023
Risks and Liquidity
Risks and Liquidity	(2) Risks and Liquidity The Company’s operations to date have focused on commercializing products, developing and acquiring technology and assets, business planning, raising capital and organization and staffing. The Company has incurred recurring losses and negative cash flows from operations since inception and has an accumulated deficit of $320.9 million as of December 31, 2023. The Company anticipates incurring additional losses until such time, if ever, it can generate sufficient revenue from its products to cover its expenses. In March 2024, the Company sold its distribution rights for NIVIS Fibrillar Collagen Pack to MiMedx Group, Inc. in exchange for an initial $5.0 million payment and additional future payments aggregating between a minimum of $3.0 million and a maximum of $7.0 million based on net sales of NIVIS over the next two years. ​ On April 21, 2023, the Company completed an underwritten public offering in which the Company sold 5,219,190 shares of its common stock (including 469,190 shares sold pursuant to the underwriters’ overallotment option on May 5, 2023) at a public offering price of $9.50 per share, receiving net proceeds of approximately $46.3 million after deducting underwriting discounts, commissions and other offering expenses. ​ The operations of the Company are subject to certain risks and uncertainties including, among others, the uncertainty of product development, the impact of macroeconomic conditions, including the lingering effects of the COVID-19 pandemic or other public health crises, general economic uncertainty, including as a result of inflationary pressures and the measures undertaken by various governments to address them, banking instability, geopolitical factors such as the ongoing Russia-Ukraine conflict and the current conflict in Israel and Gaza (including any escalation or expansion), technological uncertainty, commercial acceptance of any developed products, alternative competing technologies, dependence on collaborative partners, uncertainty regarding patents and proprietary rights, comprehensive government regulations, and dependence on key personnel.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	(3) Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) promulgated by the Financial Accounting Standards Board (“FASB”). The consolidated financial statements include the accounts of TELA Bio, Inc. and its wholly owned subsidiary TELA Bio Limited. All intercompany accounts and transactions have been eliminated in consolidation. Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and contingent liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The most significant judgments are employed in estimates used to determine the recoverability of the carrying value of the Company’s inventory. As future events and their effects cannot be determined with precision, actual results may differ significantly from these estimates. Segments Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker (“CODM”), or decision- making group, in deciding how to allocate resources and in assessing performance. The CODM, who is the Chief Executive Officer, views the Company’s operations and manages its business in Concentration of Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company places its cash with high-credit-quality financial institutions and primarily invests in money market funds. The Company has established guidelines relative to credit ratings and maturities that seek to maintain safety and liquidity. Following the events relating to Silicon Valley Bank in 2023, the Company has established additional redundant accounts with another high-credit-quality financial institution to mitigate liquidity risk to our cash and cash equivalents from any further instability in the financial industry. As described in Note 11, the Company has licensed patents and other intellectual property from Aroa Biosurgery Ltd. (“Aroa”). As part of this agreement, Aroa is also the exclusive contract manufacturer of the Company’s OviTex portfolio of products. The inability of Aroa to fulfill supply requirements of the Company could materially impact future operating results. A change in the relationship with Aroa, or an adverse change in their business, could materially impact future operating results. Cash and Cash Equivalents The Company considers cash equivalents to be highly-liquid investments with maturities of three months or less from the date of purchase. Cash equivalents consist of investments in a money market fund. The Company’s cash and cash equivalents are carried at fair value. Restricted Cash Restricted cash represents an amount held in an escrow deposit account, securing a letter of credit for the Company’s office lease. Inventory Inventory consists of purchased materials, primarily finished goods and is identified and tracked by lot and stated at the lower of cost or net realizable value, with cost being determined on a first-in, first-out basis. Inventories consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Finished goods ​ $ 13,102 ​ $ 11,792 Raw materials ​ 60 ​ — Total inventory ​ $ 13,162 ​ $ 11,792 ​ The Company periodically analyzes its inventory levels and writes down inventory that has become obsolete or that has a cost basis in excess of its expected net realizable value based on expected customer demand. As of December 31, 2023 and 2022, the Company had $3.0 million and $2.3 million, respectively, in finished goods consigned to others. Property and Equipment Property and equipment are stated at the aggregate cost incurred to acquire and place the asset in service. Expenditures for routine maintenance and repairs are charged to expense as incurred and costs of improvements and renewals are capitalized. Depreciation is provided over the estimated useful lives of the assets using the straight-line method. Intangible Assets Upfront payments and milestone payments due related to licenses or commercialization rights prior to future economic benefit being established are recorded as research and development expenses. Milestone payments due related to licenses or commercialization rights after future economic benefit is established are recorded as intangible assets. In 2023, 2022 and 2021, the Company recorded $0.4 million, $0.8 million and $0.3 million of amortization expense, respectively, related to intangible assets. At December 31, 2023, the remaining life of intangible assets was 5.6 years. The Company anticipates recognizing amortization expense of $0.4 million next five years Leases The Company adopted ASU 2016-02, Leases Long-Lived Assets Long-lived assets, such as property and equipment and intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by such asset or asset group to its carrying value. If the carrying value of the long-lived asset or asset group exceeds the undiscounted cash flows, an impairment is recognized to the extent the carrying value exceeds its fair value. Fair value is determined using various valuation techniques, including discounted cash flow models, quoted market values, and third-party independent appraisals, as considered necessary. No impairment losses were recognized during the years ended December 31, 2023, 2022 or 2021. Debt Issuance Costs Debt issuance costs incurred in connection with debt (Note 6) are amortized to interest expense over the term of the respective financing arrangement using the effective-interest method. Debt issuance costs, net of related amortization are deducted from the carrying amount of the related debt. Revenue Recognition Under ASC Topic 606, Revenue from Contracts with Customers A significant portion of the Company’s revenue is generated from product shipped to a customer or from consigned inventory maintained at hospitals. Revenue from the sale of consigned products is recognized when control is transferred to the customer, which occurs at the time the product is used in a surgical procedure. For product that is not held on consignment, the Company recognizes revenue when control transfers to the customer which occurs at the time the product is shipped or delivered. For all of the Company’s customer contracts, the only identified performance obligation is providing the product to the customer. Revenue is recognized at the estimated net sales price which includes estimates of variable consideration. The Company enters into contracts with certain third-party payors for the payment of rebates with respect to the utilization of its products. These rebates are based on contractual percentages. The Company estimates and records rebates in the same period the related revenue is recognized, resulting in a reduction of product revenue. Payment terms with customers do not exceed one year and, therefore, the Company does not account for a financing component in its arrangements. There are no incremental costs of obtaining a contract that would rise to or enhance an asset other than product costs, which are a component of inventory. The Company expenses incremental costs of obtaining a contract with a customer (e.g., sales commissions) when incurred as the period of benefit is less than one year. Fees charged to customers for shipping are recognized as revenue. The following table presents revenue disaggregated (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2023 ​ 2022 ​ 2021 OviTex ​ $ 39,416 ​ $ 28,879 ​ $ 22,990 OviTex PRS ​ ​ 18,736 ​ ​ 12,431 ​ ​ 6,473 Other ​ ​ 301 ​ ​ 108 ​ ​ — Total revenue ​ $ 58,453 ​ $ 41,418 ​ $ 29,463 ​ Sales outside of the U.S. were $6.1 million or 10% of total revenue for the year ended December 31, 2023, $3.2 million or 8% of total revenue for the year ended December 31, 2022 and immaterial for the year ended December 31, 2021. Research and Development Research and development costs are charged to expense as incurred and consist primarily of salaries, benefits, and other related costs, including stock-based compensation for personnel serving in the research and development functions as well as costs incurred with Aroa under development agreements related to technology transfer, laboratory materials and supplies. At the end of the reporting period, the Company compares payments made to third-party service providers to the estimated progress toward completion of the research or development objectives. Such estimates are subject to change as additional information becomes available. Depending on the timing of payments to the service providers and the progress that the Company estimates has been made as a result of the service provided, the Company may record net prepaid or accrued expense relating to these costs. Costs incurred in obtaining patent and other intellectual property licenses or milestone payments from license agreements for which there are no alternative future uses are charged to expense as incurred. Stock-Based Compensation The Company accounts for stock-based awards in accordance with provisions of ASC Topic 718, Compensation—Stock Compensation Income Taxes Income taxes are accounted for under the asset-and-liability method as required by ASC Topic 740, Income Taxes ASC Subtopic 740-10, Accounting for Uncertainty of Income Taxes Fair value of financial instruments Fair value is the price that could be received to sell an asset or paid to transfer a liability in an orderly transaction among market participants. Fair value determination in accordance with applicable accounting guidance requires that a number of significant judgments are made. Additionally, fair value is used on a nonrecurring basis to evaluate assets for impairment or as required for disclosure purposes by applicable accounting guidance on disclosures about fair value of financial instruments. Depending on the nature of the assets and liabilities, various valuation techniques and assumptions are used when estimating fair value. The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, other assets, and accounts payable are shown at cost, which approximates fair value due to the short-term nature of these instruments. The carrying amount of the Company’s Credit and Security Agreement approximates fair value due to its variable interest rate. The Company follows the provisions of ASC Topic 820, Fair Value Measurement ● Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. ● Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liabilities. ● Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). The following fair value hierarchy table presents information about each major category of the Company’s financial assets and liabilities measured at fair value on a recurring basis (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value measurement at reporting date using ​ ​ Quoted prices in ​ ​ ​ ​ ​ ​ ​ ​ active markets ​ Significant other ​ Significant ​ ​ for identical ​ observable ​ unobservable ​ ​ assets ​ inputs ​ inputs ​ (Level 1) (Level 2) (Level 3) December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents – money market fund ​ $ 41,561 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents – money market fund ​ $ 39,010 ​ $ — ​ $ — ​ Allowance for credit losses The following table presents a rollforward of the allowance of credit losses (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at Beginning of Period ​ Bad Debt Expense Recognized ​ Write-offs of Uncollectible Balances ​ ​ Balance at End of Period Year ended December 31, 2021 $ (46) ​ (12) ​ 6 ​ $ (52) Year ended December 31, 2022 $ (52) ​ (116) ​ 25 ​ $ (143) Year ended December 31, 2023 $ (143) ​ (306) ​ 33 ​ $ (416) ​ Net loss per share Basic and diluted net loss per common share is determined by dividing net loss by the weighted-average shares of common stock outstanding during the reporting period. In periods in which the Company reports a net loss, diluted net loss per share is the same as basic net loss per share since dilutive shares are not assumed to have been issued if their effect is antidilutive. Therefore, the weighted-average shares used to calculate both basic and diluted loss per share are the same. The following potentially dilutive securities have been excluded from the computation of diluted weighted-average shares outstanding, as they would be antidilutive. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2023 ​ 2022 ​ 2021 Stock options (including shares subject to repurchase) ​ 2,162,453 2,071,848 ​ 1,706,438 Unvested restricted stock units ​ 907,203 ​ 311,991 ​ 163,043 Common stock warrants ​ 88,556 ​ 88,556 ​ 88,556 Total 3,158,212 2,472,395 ​ 1,958,037 ​ Recently Issued Accounting Pronouncements The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments ​ In August 2020, the FASB issued ASU No. 2020-06, Debt with Conversion and Other Options and Derivatives and Hedging - Contracts in Entity’s Own Equity (“ . In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures interim period. The Company is currently evaluating the expected impact that the standard could have on its consolidated financial statements and related disclosures. ​ In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2023
Property and Equipment
Property and Equipment	(4) Property and Equipment Property and equipment consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, Asset description Estimated useful lives 2023 2022 Lab equipment 5 Years ​ $ 2,883 ​ $ 2,635 Furniture and fixtures 5 Years ​ 284 ​ 274 Computer equipment and software 3 Years ​ 645 ​ 604 Leasehold improvements Lesser of useful life or lease term ​ 2,507 ​ 2,309 Total ​ 6,319 ​ 5,822 Less accumulated depreciation and amortization ​ (4,335) ​ (4,140) Property and equipment, net ​ $ 1,984 ​ $ 1,682 ​ The cost of property and equipment at both December 31, 2023 and 2022 includes $0.2 million of equipment located at Aroa. Depreciation expense was $0.4 million, $0.4 million and $0.2 million for the years ended December 31, 2023, 2022 and 2021, respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2023
Accrued Expenses and Other Current Liabilities
Accrued Expenses and Other Current Liabilities	(5) Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Compensation and related benefits ​ $ 9,216 ​ $ 6,420 Third-party and professional fees ​ 2,828 ​ 2,563 Amounts due to contract manufacturer ​ ​ 2,024 ​ ​ 1,263 Current portion of operating lease liabilities ​ ​ 565 ​ ​ 340 Research and development expenses ​ ​ 140 ​ ​ 137 Other ​ 527 ​ 146 Total accrued expenses and other current liabilities ​ $ 15,300 ​ $ 10,869 ​

Debt

Debt	12 Months Ended
	Dec. 31, 2023
Debt
Debt	(6) Debt Long-term debt consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 MidCap Term Loan ​ $ 40,000 ​ $ 40,000 End of term charge ​ 2,000 ​ 2,000 Unamortized end of term charge and issuance costs ​ (1,485) ​ (2,084) Long-term debt ​ $ 40,515 ​ $ 39,916 ​ MidCap Term Loan On May 26, 2022, the Company entered into the Credit and Security Agreement (the “MidCap Credit Agreement”) with MidCap Financial Trust, as agent (the “Agent”), and certain lender parties thereto. The MidCap Credit Agreement provides for up to $50.0 million in term loans (the “MidCap Term Loans”), consisting of a $40.0 million Tranche 1 (“Tranche 1”) and a $10.0 million Tranche 2 (“Tranche 2”). Upon closing, the Company borrowed $40.0 million of Tranche 1 and used a portion of the proceeds to repay borrowings under the OrbiMed Credit Facility (described below) and intends to use the remaining proceeds to fund operations and other general corporate purposes. As of December 31, 2023, no additional borrowings were made and the Company’s ability to draw from Tranche 2 has since expired. ​ Pursuant to the MidCap Credit Agreement, the Company provided a first priority security interest in all existing and future acquired assets, including intellectual property, owned by the Company. The MidCap Credit Agreement contains certain covenants that limit the Company’s ability to engage in certain transactions that may be in the Company’s long-term best interests, including the incurrence of additional indebtedness, effecting certain corporate changes, making certain investments, acquisitions or dispositions and paying dividends. ​ The MidCap Credit Agreement also contains customary indemnification obligations and customary events of default, including, among other things, (i) non-payment, (ii) breach of warranty, (iii) non-performance of covenants and obligations, (iv) default on other indebtedness, (v) judgments, (vi) change of control, (vii) bankruptcy and insolvency, (viii) impairment of security, (ix) key permit events, (x) termination of a pension plan, (xi) regulatory matters, (xii) material adverse effect and (xiii) breach of material contracts. ​ In addition, the Company must maintain minimum net revenue levels tested quarterly. In the event of default under the MidCap Credit Agreement, the Company would be required to pay interest on principal and all other due and unpaid obligations at the current rate in effect plus 2%. ​ The MidCap Term Loans mature on May 1, 2027 and bear interest at a rate equal to 6.25% plus the greater of one-month Term SOFR (as defined in the MidCap Credit Agreement) or 1.0%. The Company is required to make 36 monthly interest payments beginning on June 1, 2022 (the “Interest-Only Period”). If the Company is in covenant compliance at the end of the Interest-Only Period, the Company will have the option to extend the Interest-Only Period by 12 months to 48 monthly interest payments, followed by 12 months of straight-line amortization, with the entire principal payment due at maturity. If the Company is not in covenant compliance at the end of the Interest-Only Period, the Company is required to make 24 months of straight-line amortization payments, with the entire principal amount due at maturity. ​ Subject to certain limitations, the MidCap Term Loans have a prepayment fee equal to 3.0% of the prepaid principal amount for the first year following the closing date of the MidCap Term Loans, 2.0% of the prepaid principal amount for the second year following the closing date and 1.0% of the prepaid principal amount for the third year following the closing date and thereafter. The Company is also required to pay an exit fee at the time of maturity or prepayment event equal to 5% of all principal borrowings (the “End of Term Charge”) (or in the event of a prepayment event, the amount of principal being prepaid). Interest expense associated with the MidCap Credit Facility recorded for the year ended December 31, 2023 was $5.2 million, of which $0.6 million was related to the amortization of debt issuance costs. Interest expense associated with the MidCap Credit Facility recorded for the year ended December 31, 2022 was $2.6 million, of which $0.4 million was related to the amortization of debt issuance costs. ​ OrbiMed Term Loan In November 2018, the Company entered into the OrbiMed Credit Facility with OrbiMed, a related party as the lender is affiliated with a stockholder of the Company, which consisted of up to $35.0 million in term loans (the “OrbiMed Term Loans”). The OrbiMed Term Loans consisted of two tranches, a $30.0 million Tranche 1 (“First Tranche”) and a $5.0 million Tranche 2 (“Second Tranche”). In November 2018, the Company borrowed $30.0 million of the First Tranche. The Company elected not to borrow the Second Tranche prior to its expiration on December 31, 2019. On May 26, 2022, the Company entered into the MidCap Credit Agreement and upon closing used a portion of the proceeds to repay all borrowings under the OrbiMed Credit Facility. The OrbiMed Term Loan bore interest at a rate equal to 7.75% plus the greater of one-month LIBOR or 2.0% until the aggregate principal, interest and End of Term Charge of $3.0 million were paid with part of the proceeds received from the MidCap Credit Agreement. As a result of these payments, a $1.2 million loss on extinguishment was recorded during the year ended December 31, 2022. Interest expense associated with the OrbiMed Credit Facility recorded for the year ended December 31, 2022 was $1.5 million, of which $0.3 million was related to the amortization of debt issuance costs. Interest expense associated with the OrbiMed Credit Facility recorded for the year ended December 31, 2021 was $3.6 million, of which $0.7 million was related to the amortization of debt issuance costs.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity
Stockholders' Equity	(7) Stockholders’ Equity Public Stock Offerings In November 2023, the Company entered into a new Equity Distribution Agreement (the “2023 Equity Agreement”) with Piper Sandler & Co, (“Piper”) in connection with the establishment of an at-the-market offering program under which the Company may sell shares of its common stock, from time to time through Piper as sales agent, in an initial amount of up to $50 million. The 2023 Equity Agreement supersedes and replaces the Company’s previous Equity Distribution Agreement with Piper dated December 18, 2020 (the “2020 Equity Agreement”), which is no longer effective. No sales were made under the 2023 Equity Agreement or the 2020 Equity Agreement during the years ended December 31, 2023, 2022 or 2021. In April 2023, the Company completed an underwritten public offering in which the Company issued and sold 5,219,190 shares of its common stock (including 469,190 shares sold pursuant to the underwriters’ overallotment option in May 2023) at a public offering price of $9.50 per share. The Company received net proceeds of approximately $46.3 million after deducting underwriting discounts, commissions and other offering expenses. ​ In August 2022, the Company completed an underwritten public offering in which the Company issued and sold 4,600,000 shares of its common stock at a public offering price of $8.00 per share. The Company received net proceeds of $34.4 million after deducting underwriting discounts, commissions and other offering expenses. ​ ​ Warrants ​ The Company had the following warrants outstanding at December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Exercise ​ Expiration ​ Outstanding ​ price dates Common stock warrants 8,379 ​ $ 28.65 2028 Common stock warrants 80,177 ​ 28.65 2027 ​ 88,556 ​ ​ ​ ​ ​ ​

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2023
Stock-Based Compensation
Stock-Based Compensation	(8) Stock-Based Compensation The Company has two equity incentive plans: the 2012 Stock Incentive Plan and the Amended and Restated 2019 Equity Incentive Plan. New awards can only be granted under the Amended and Restated 2019 Equity Incentive Plan (the “Plan”). At December 31, 2023, 1,138,279 shares of common stock were available for future issuances under the Plan. The Plan is subject to an annual increase, subject to prior approval by the Company’s board of directors, equal to the lesser of (i) 432,442 shares, (ii) 4% of the shares outstanding on the last day of the immediately preceding fiscal year and (iii) such smaller number of shares as determined by the board of directors. The Plan provides for the grant of incentive stock options, nonqualified stock options, restricted stock awards, restricted stock units and/or stock appreciation rights to employees, directors, and other persons, as determined by the Company’s board of directors. The Company’s stock options vest based on the terms in each award agreements and generally vest over four years and have a term of 10 years The Company measures employee and nonemployee stock-based awards at grant-date fair value and records compensation expense ratably over the vesting period of the award. The Company recorded stock-based compensation expense in the following expense categories of its accompanying consolidated statements of operations and comprehensive loss (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2023 ​ 2022 ​ 2021 Sales and marketing ​ $ 1,824 ​ $ 1,373 ​ $ 961 General and administrative ​ 2,478 ​ 2,029 ​ 1,542 Research and development ​ 730 ​ 587 ​ 1,158 Total stock‑based compensation ​ $ 5,032 ​ $ 3,989 ​ $ 3,661 ​ The following table summarizes stock option activity for the Plan: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ average ​ ​ ​ ​ Weighted ​ remaining ​ ​ Number of ​ average exercise ​ contractual term ​ shares price per share (years) Outstanding at January 1, 2021 1,498,208 ​ $ 10.87 Granted 468,000 ​ 14.80 Exercised (77,154) ​ 7.08 Canceled/forfeited (182,645) ​ 13.08 Outstanding at December 31, 2021 1,706,409 ​ $ 11.88 ​ Granted 450,410 ​ 10.24 Exercised (3,563) ​ 5.51 Canceled/forfeited (81,408) ​ 13.13 Outstanding at December 31, 2022 ​ 2,071,848 ​ $ 11.49 ​ ​ Granted ​ 212,960 ​ ​ 10.50 ​ ​ Exercised ​ (25,428) ​ ​ 5.00 ​ ​ Canceled/forfeited ​ (96,927) ​ ​ 11.25 ​ ​ Outstanding at December 31, 2023 ​ 2,162,453 ​ $ 11.48 ​ 6.26 Vested and expected to vest at December 31, 2023 2,131,840 ​ $ 11.48 6.23 Exercisable at December 31, 2023 1,606,779 ​ $ 11.50 5.50 ​ Included in outstanding options at December 31, 2023, were 355,766 stock options granted outside of the Plan. These grants were made pursuant to the Nasdaq inducement grant exception in accordance with Nasdaq listing rule 5635(c)(4). At December 31, 2023, the aggregate intrinsic value of both outstanding options and exercisable options was $0.3 million. The 2012 Stock Incentive Plan provided the holders of stock options an election to early exercise prior to vesting. The Company had the right, but not the obligation, to repurchase early exercised options without transferring any appreciation to the employee if the employee terminates employment before the end of the original vesting period. The repurchase price is the lesser of the original exercise price or the then fair value of the common stock. At December 31, 2022, all early exercised options had vested. The following table summarizes activity relating to early exercise of stock options: ​ ​ ​ ​ ​ ​ Number of ​ shares Unvested balance at January 1, 2021 182 Vested (153) Unvested balance at December 31, 2021 ​ 29 Vested ​ (29) Unvested balance at December 31, 2022 — ​ The weighted average grant-date fair value per share of options granted was $7.19, $6.55 and $8.66 for the years ended December 31, 2023, 2022 and 2021, respectively. The aggregate intrinsic value of options exercised was $0.1 million, $16,000 and $0.4 million for the years ended December 31, 2023, 2022 and 2021, respectively. As of December 31, 2023, the total unrecognized compensation expense related to unvested employee and nonemployee stock option awards was $3.5 million, which is expected to be recognized in expense over a weighted-average period of approximately 2.2 years. Estimating Fair Value of Stock Options The fair value of each grant of stock options was determined by the Company using the methods and assumptions discussed below. Certain of these inputs are subjective and generally require judgment to determine. Expected term Expected volatility Risk-free interest rate Expected dividend The fair value of each option was estimated on the date of grant using the weighted average assumptions in the table below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2023 ​ 2022 2021 ​ Expected dividend yield — ​ — ​ — ​ Expected volatility 74.3 % 69.6 % 63.9 % Risk‑free interest rate 3.99 % 2.55 % 0.99 % Expected term (in years) 6.15 ​ 6.20 ​ 6.15 ​ ​ Restricted Stock Units The Company has issued service-based and performance-based restricted stock units (“RSUs”). During the year ended December 31, 2023, the Company granted 479,585 service-based awards at a weighted average grant-date fair value of $9.89 per RSU. Vesting of the service-based RSUs is based on the terms in each award agreement and is generally over four years. During the year ended December 31, 2023, the Company granted 250,149 performance-based RSUs at a weighted average grant-date fair value of $10.95 per RSU. Vesting of these performance-based RSUs is subject to continued service through 2026 and the achievement of certain performance milestones for fiscal year 2026. The amount of RSUs that will vest can range from 0% to 110% of the original number of RSUs granted. Expense for the performance-based RSUs is not recognized until the performance conditions are deemed probable of achievement. The Company did not record any expense related to the performance-based RSUs during the year ended December 31, 2023. ​ The following table summarizes restricted stock units for the Plan: ​ ​ ​ ​ ​ ​ Number of ​ shares Outstanding at January 1, 2021 ​ — Granted ​ 194,232 Vested ​ (12,000) Canceled/forfeited ​ (19,189) Outstanding at December 31, 2021 ​ 163,043 Granted ​ 197,950 Vested ​ (40,783) Canceled/forfeited ​ (8,219) Outstanding at December 31, 2022 ​ 311,991 Granted ​ 729,734 Vested ​ (101,559) Canceled/forfeited ​ (32,963) Outstanding at December 31, 2023 ​ 907,203 ​ Included in outstanding RSUs at December 31, 2023, were 123,250 RSUs granted outside of the Plan. These grants were made pursuant to the Nasdaq inducement grant exception in accordance with Nasdaq listing rule 5635(c)(4). The weighted average grant-date fair value per RSU granted was $10.25, $11.21 and $16.57 during the years ended December 31, 2023, 2022 and 2021, respectively. The aggregate intrinsic value of RSUs outstanding was $6.0 million and $3.6 million at December 31, 2023 and 2022, respectively. The total unrecognized compensation expense at December 31, 2023 related to RSUs was $4.8 million, which is expected to be recognized in expense over a weighted-average period of approximately 2.9 years.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2023
Employee Benefit Plans
Employee Benefit Plans	(9) Employee Benefit Plans 401(k) Defined Contribution Plan The Company sponsors a 401(k) defined-contribution plan covering all employees. Participants are permitted to contribute up to 100% of their eligible annual pretax compensation up to an established federal limit on aggregate participant contributions. Discretionary contributions made by the Company, if any, are determined annually by the board of directors. Effective January 1, 2020, the Company matched 50% of employees’ contributions up to 6%, subject to a maximum annual amount. The Company’s contributions were $0.5 million, $0.4 million and $0.3 million for the years ended December 31, 2023, 2022 and 2021, respectively. Participants are immediately vested in their own contributions to the plan and are fully vested in discretionary profit sharing made by the Company after three years of service. 2019 Employee Stock Purchase Plan In November 2019, the Company adopted the 2019 Employee Stock Purchase Plan (the “ESPP”). At December 31, 2023, 518,350 shares were available for future issuance under the ESPP. The ESPP is subject to an annual increase, subject to prior approval by the Company’s board of directors, equal to the least of (i) 107,887 shares of common stock, (ii) 1% of the shares outstanding on the final day of the immediately preceding calendar year, and (iii) such smaller number of shares as determined by the board of directors. The ESPP provides the opportunity to purchase the Company’s common stock at a 15% discount to the market price through payroll deductions. As of December 31, 2023, 2022 and 2021, 10,602, 4,523 and 3,163 shares, respectively, have been issued under the ESPP.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Taxes
Income Taxes	(10) Income Taxes The Company has incurred losses since inception. Deferred tax assets and liabilities are determined based on the differences between the financial statement carrying amounts and tax bases of assets and liabilities using enacted tax rates in effect for years in which differences are expected to reverse. Significant components of the Company’s deferred tax assets for federal income taxes consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Deferred tax assets ​ ​ ​ ​ ​ Net operating loss carryforwards ​ $ 61,427 ​ $ 55,091 Interest expense carryforward ​ ​ 523 ​ ​ — Research and development credits ​ 830 ​ 623 Lease liability ​ ​ 557 ​ ​ 387 Capitalized research and development expenses ​ ​ 4,845 ​ ​ 1,743 Accrued expenses and other ​ 3,535 ​ 2,682 Inventory reserve ​ 289 ​ 372 Gross deferred tax asset ​ 72,006 ​ 60,898 Deferred tax liabilities ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ (436) ​ (435) Right of use asset ​ ​ (484) ​ ​ (302) Gross deferred tax liability ​ (920) ​ ​ (737) Net deferred tax asset before valuation allowance ​ ​ 71,086 ​ ​ 60,161 Valuation allowance ​ (71,086) ​ (60,161) Net deferred tax asset ​ $ — ​ $ — ​ The Company does not have unrecognized tax benefits as of December 31, 2023 and 2022. The Company recognizes interest and penalties accrued on any unrecognized tax benefits as a component of income tax expense. The Company’s net operating loss (“NOL”) carryforwards for federal and state income tax purposes consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 NOL carryforwards ​ ​ ​ ​ ​ ​ Federal ​ $ 239,417 ​ $ 212,314 State ​ 196,132 ​ 173,472 ​ The NOL carryforwards begin expiring in 2032 for federal purposes and in 2027 for state income tax purposes yet $160.0 million of the federal NOL carryforwards have no expiration. The Company recorded a valuation allowance on the deferred tax assets as of December 31, 2023 and 2022 because of the uncertainty of their realization. The valuation allowance increased by $10.9 million and $10.4 million for the years ended December 31, 2023 and 2022, respectively, mainly due to losses incurred. Utilization of the net operating losses and general business tax credits carryforwards may be subject to a substantial limitation under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, if changes in ownership of the company have occurred previously or occur in the future. Ownership changes may limit the amount of net operating losses and general business tax credits carryforwards that can be utilized annually to offset future taxable income and tax, respectively. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of 5% shareholders in the stock of a corporation by more than 50 percentage points over a three-year period. If the Company experiences a Section 382 ownership change, the tax benefits related to the NOL carryforwards may be further limited or lost. The Company has not performed an analysis under Section 382 and cannot predict or otherwise determine whether there would be any limitation to the amount of net operating losses and general business tax credits carryforwards that can be utilized. A reconciliation of income tax benefit at the statutory federal income tax rate and as reflected in the consolidated financial statements is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2023 2022 2021 ​ Rate reconciliation ​ ​ ​ ​ ​ Federal tax benefit at statutory rate (21.0) % (21.0) % (21.0) % State rate, net of federal benefit (3.1) (3.1) ​ (3.5) ​ Permanent differences 0.7 0.6 ​ 0.2 ​ Research and development (0.4) — ​ 0.4 ​ Change in valuation allowance 23.4 23.4 ​ 24.2 ​ Other 0.4 0.1 ​ (0.3) ​ Total tax provision — % — % — % ​ The Company files income tax returns in the U.S. federal jurisdiction, various state jurisdictions and the United Kingdom. Tax years 2020 and forward remain open for examination for federal and the Company’s more significant state tax jurisdictions. Carryforward attributes from prior years may be adjusted upon examination by taxing authorities if used in an open period.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	(11) Commitments and Contingencies Legal Proceedings From time to time, the Company may be a party to lawsuits, claims, and other legal proceedings that arise in the ordinary course of its business. While the outcomes of these matters are uncertain, management does not expect that the ultimate costs to resolve these matters will have a material adverse effect on the Company’s consolidated financial position, results of operations, or cash flows. Agreements with Aroa In August 2012, the Company entered into a License, Product Development, and Supply Umbrella Agreement (“Aroa Agreement”) with Aroa. The Aroa Agreement provides the Company a license to patent rights and other intellectual property related to Aroa’s products and technologies for use in certain indications and expires on the expiration of the last patent covering the products (currently March 9, 2031). The Company has the right to extend the term of the agreement by an additional 10 years following the expiration of the last patent covering the products on commercially reasonable terms to be negotiated by the parties. This agreement initially limited the Company’s license rights to the U.S. but was subsequently amended in March 2013 to include certain countries in Europe including the United Kingdom and members of the European Union and certain former Union of Soviet Socialist Republic satellite nations. The Aroa Agreement required payments aggregating up to $4.0 million upon the achievement of U.S. and European cumulative product sales targets. The Company paid $1.0 million to Aroa in 2018 related to one of the cumulative product sales targets and the remaining $2.0 million in 2019. The Company paid $1.0 million in 2022 related to the sales milestone payments in the European territory. Other key terms of the amended Aroa agreement in addition to those disclosed above are as follows: ● The transfer price for product produced by Aroa is 200% of Aroa’s cost of goods sold, or 150% of Aroa’s cost of goods sold for the Company’s recent products dedicated for use in inguinal hernia repair (“IHR”). The transfer price and the quarterly true-up amount continued to equal 27% of Company’s net sales of licensed products, with the exception of the IHR products, where the total amount payable to Aroa will at least equal the aggregate transfer pricing paid to Aroa for such products during the applicable calendar year. ● Provisions exist for the Company to step in and operate Aroa’s plant if a supply failure occurs and is not cured within a set timeframe. Under the amended agreement, the criteria for a supply failure was modified to mean a failure by Aroa to timely supply, during any consecutive 60-day period, at least 75% of the products ordered by the Company under binding purchase orders. During the period that the Company steps in and assumes manufacturing responsibility, it shall not be required to purchase product from or pay transfer prices to Aroa, the annual minimums shall be proportionately reduced to reflect the lack of supply responsibility by Aroa and the Company shall pay a royalty of 6% of net sales in lieu of 27% of net sales of the licensed products. The Company expects to enter into similar milestone-based agreements with its strategic partner for both product territories and new products in order to expand and extend its product portfolio. As of December 31, 2023, the Company had $7.1 million in commitments with one supplier to maintain exclusivity rights over time and $1.8 million in milestone payments related to certain research and development arrangements which are currently deemed not probable as the timing and likelihood of such payments are not known with certainty. Employment Agreements The Company entered into employment agreements with key personnel providing for compensation and severance in certain circumstances, as defined in the respective employment agreements. Leases The Company leases office and laboratory space in Malvern, Pennsylvania under a noncancelable lease (the “Malvern Lease”). The Malvern Lease, which was concluded to be an operating lease, was amended in October 2023 to extend the term of the lease from May 2028 to May 2030 (the “Lease Amendment”). Pursuant to the Lease Amendment, the Company leased an additional 15,881 square feet at the Company’s corporate headquarters which commenced on December 1, 2023 (the “Expansion Premises”) and will relinquish 4,652 square feet of non-contiguous space currently subject to the lease agreement on June 30, 2025 (the “Relinquished Space”). The Expansion Premises increased the Company’s total leased square footage in the building from 24,725 square feet to 40,606 square feet, which will be subsequently reduced to 35,954 square feet as of June 30, 2025 following removal of the Relinquished Space. The modification of the lease terms for the Company’s existing space was not treated as a separate contract; however, the Company notes that the Expansion Premises is being treated as a new ROU asset. The Lease Amendment required the Company to pay an additional security deposit of $0.3 million. The Malvern Lease has annual scheduled payment increases and provides the Company with a renewal option for an additional term of 60 months at the end of the lease term. The Company evaluates renewal options at lease inception and on an ongoing basis and includes renewal options that it is reasonably certain to exercise in its expected lease terms when classifying leases and measuring lease liabilities. As the Company is not reasonably certain to exercise the renewal option, the additional 60-month term has been excluded. ​ Operating lease leasehold improvements are depreciated over the lesser of the useful lives of the leasehold improvements or the lease term. ​ The Company determined that the rate implicit in its lease is not readily determinable, and therefore, the Company uses its incremental borrowing rate as the discount rate when measuring operating lease liabilities. The incremental borrowing rate represents an estimate of the interest rate the Company would incur at lease commencement to borrow an amount equal to the lease payments on a collateralized basis over the term of a lease. The Company used an incremental borrowing rate of 11.66% to discount the Malvern Lease payments included in the operating lease liabilities recognized. ​ The Company recognized $0.3 million of lease cost during both the years ended December 31, 2023 and 2022. Cash paid for amounts included in the measurement of operating lease liabilities was $0.4 million and $0.3 million for the years ended December 31, 2023 and 2022, respectively, and these amounts are included in operating activities in the consolidated statements of cash flows. As of December 31, 2023, the remaining lease term for the Malvern Lease is 6.4 years. ​ The following table reconciles the undiscounted future minimum lease payments (displayed in aggregate by year) under non-cancelable operating leases with terms of more than one year to the total operating lease liabilities recognized on the consolidated balance sheets as of December 31, 2023 (in thousands): ​ ​ ​ ​ 2024 $ 601 2025 580 2026 ​ 557 2027 ​ 570 2028 ​ 583 Thereafter ​ 845 Total undiscounted future minimum lease payments $ 3,736 Less imputed interest ​ (1,486) Total operating lease liabilities $ 2,250 ​ As of December 31, 2023, $0.6 million representing the current portion of operating lease liabilities is included in accrued expenses and other current liabilities other long-term liabilities in the consolidated balance sheets.

Subsequent Event

Subsequent Event	12 Months Ended
	Dec. 31, 2023
Subsequent Event.
Subsequent Event	(12) Subsequent Event ​ In March 2024, the Company sold its distribution rights for NIVIS Fibrillar Collagen Pack to MiMedx Group, Inc. in exchange for an initial $5.0 million payment and additional future payments aggregating between a minimum of $3.0 million and a maximum of $7.0 million based on net sales of NIVIS over the next two years. ​

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Summary of Significant Accounting Policies
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) promulgated by the Financial Accounting Standards Board (“FASB”). The consolidated financial statements include the accounts of TELA Bio, Inc. and its wholly owned subsidiary TELA Bio Limited. All intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and contingent liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The most significant judgments are employed in estimates used to determine the recoverability of the carrying value of the Company’s inventory. As future events and their effects cannot be determined with precision, actual results may differ significantly from these estimates.
Segments	Segments Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker (“CODM”), or decision- making group, in deciding how to allocate resources and in assessing performance. The CODM, who is the Chief Executive Officer, views the Company’s operations and manages its business in
Concentration of Risk	Concentration of Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company places its cash with high-credit-quality financial institutions and primarily invests in money market funds. The Company has established guidelines relative to credit ratings and maturities that seek to maintain safety and liquidity. Following the events relating to Silicon Valley Bank in 2023, the Company has established additional redundant accounts with another high-credit-quality financial institution to mitigate liquidity risk to our cash and cash equivalents from any further instability in the financial industry. As described in Note 11, the Company has licensed patents and other intellectual property from Aroa Biosurgery Ltd. (“Aroa”). As part of this agreement, Aroa is also the exclusive contract manufacturer of the Company’s OviTex portfolio of products. The inability of Aroa to fulfill supply requirements of the Company could materially impact future operating results. A change in the relationship with Aroa, or an adverse change in their business, could materially impact future operating results.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers cash equivalents to be highly-liquid investments with maturities of three months or less from the date of purchase. Cash equivalents consist of investments in a money market fund. The Company’s cash and cash equivalents are carried at fair value.
Restricted Cash	Restricted Cash Restricted cash represents an amount held in an escrow deposit account, securing a letter of credit for the Company’s office lease.
Inventory	Inventory Inventory consists of purchased materials, primarily finished goods and is identified and tracked by lot and stated at the lower of cost or net realizable value, with cost being determined on a first-in, first-out basis. Inventories consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Finished goods ​ $ 13,102 ​ $ 11,792 Raw materials ​ 60 ​ — Total inventory ​ $ 13,162 ​ $ 11,792 ​ The Company periodically analyzes its inventory levels and writes down inventory that has become obsolete or that has a cost basis in excess of its expected net realizable value based on expected customer demand. As of December 31, 2023 and 2022, the Company had $3.0 million and $2.3 million, respectively, in finished goods consigned to others.
Property and Equipment	Property and Equipment Property and equipment are stated at the aggregate cost incurred to acquire and place the asset in service. Expenditures for routine maintenance and repairs are charged to expense as incurred and costs of improvements and renewals are capitalized. Depreciation is provided over the estimated useful lives of the assets using the straight-line method.
Intangible Assets	Intangible Assets Upfront payments and milestone payments due related to licenses or commercialization rights prior to future economic benefit being established are recorded as research and development expenses. Milestone payments due related to licenses or commercialization rights after future economic benefit is established are recorded as intangible assets. In 2023, 2022 and 2021, the Company recorded $0.4 million, $0.8 million and $0.3 million of amortization expense, respectively, related to intangible assets. At December 31, 2023, the remaining life of intangible assets was 5.6 years. The Company anticipates recognizing amortization expense of $0.4 million next five years
Leases	Leases The Company adopted ASU 2016-02, Leases
Long-Lived Assets	Long-Lived Assets Long-lived assets, such as property and equipment and intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by such asset or asset group to its carrying value. If the carrying value of the long-lived asset or asset group exceeds the undiscounted cash flows, an impairment is recognized to the extent the carrying value exceeds its fair value. Fair value is determined using various valuation techniques, including discounted cash flow models, quoted market values, and third-party independent appraisals, as considered necessary. No impairment losses were recognized during the years ended December 31, 2023, 2022 or 2021.
Debt Issuance Costs	Debt Issuance Costs Debt issuance costs incurred in connection with debt (Note 6) are amortized to interest expense over the term of the respective financing arrangement using the effective-interest method. Debt issuance costs, net of related amortization are deducted from the carrying amount of the related debt.
Revenue Recognition	Revenue Recognition Under ASC Topic 606, Revenue from Contracts with Customers A significant portion of the Company’s revenue is generated from product shipped to a customer or from consigned inventory maintained at hospitals. Revenue from the sale of consigned products is recognized when control is transferred to the customer, which occurs at the time the product is used in a surgical procedure. For product that is not held on consignment, the Company recognizes revenue when control transfers to the customer which occurs at the time the product is shipped or delivered. For all of the Company’s customer contracts, the only identified performance obligation is providing the product to the customer. Revenue is recognized at the estimated net sales price which includes estimates of variable consideration. The Company enters into contracts with certain third-party payors for the payment of rebates with respect to the utilization of its products. These rebates are based on contractual percentages. The Company estimates and records rebates in the same period the related revenue is recognized, resulting in a reduction of product revenue. Payment terms with customers do not exceed one year and, therefore, the Company does not account for a financing component in its arrangements. There are no incremental costs of obtaining a contract that would rise to or enhance an asset other than product costs, which are a component of inventory. The Company expenses incremental costs of obtaining a contract with a customer (e.g., sales commissions) when incurred as the period of benefit is less than one year. Fees charged to customers for shipping are recognized as revenue. The following table presents revenue disaggregated (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2023 ​ 2022 ​ 2021 OviTex ​ $ 39,416 ​ $ 28,879 ​ $ 22,990 OviTex PRS ​ ​ 18,736 ​ ​ 12,431 ​ ​ 6,473 Other ​ ​ 301 ​ ​ 108 ​ ​ — Total revenue ​ $ 58,453 ​ $ 41,418 ​ $ 29,463 ​ Sales outside of the U.S. were $6.1 million or 10% of total revenue for the year ended December 31, 2023, $3.2 million or 8% of total revenue for the year ended December 31, 2022 and immaterial for the year ended December 31, 2021.
Research and Development	Research and Development Research and development costs are charged to expense as incurred and consist primarily of salaries, benefits, and other related costs, including stock-based compensation for personnel serving in the research and development functions as well as costs incurred with Aroa under development agreements related to technology transfer, laboratory materials and supplies. At the end of the reporting period, the Company compares payments made to third-party service providers to the estimated progress toward completion of the research or development objectives. Such estimates are subject to change as additional information becomes available. Depending on the timing of payments to the service providers and the progress that the Company estimates has been made as a result of the service provided, the Company may record net prepaid or accrued expense relating to these costs. Costs incurred in obtaining patent and other intellectual property licenses or milestone payments from license agreements for which there are no alternative future uses are charged to expense as incurred.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for stock-based awards in accordance with provisions of ASC Topic 718, Compensation—Stock Compensation
Income Taxes	Income Taxes Income taxes are accounted for under the asset-and-liability method as required by ASC Topic 740, Income Taxes ASC Subtopic 740-10, Accounting for Uncertainty of Income Taxes
Fair value of financial instruments	Fair value of financial instruments Fair value is the price that could be received to sell an asset or paid to transfer a liability in an orderly transaction among market participants. Fair value determination in accordance with applicable accounting guidance requires that a number of significant judgments are made. Additionally, fair value is used on a nonrecurring basis to evaluate assets for impairment or as required for disclosure purposes by applicable accounting guidance on disclosures about fair value of financial instruments. Depending on the nature of the assets and liabilities, various valuation techniques and assumptions are used when estimating fair value. The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, other assets, and accounts payable are shown at cost, which approximates fair value due to the short-term nature of these instruments. The carrying amount of the Company’s Credit and Security Agreement approximates fair value due to its variable interest rate. The Company follows the provisions of ASC Topic 820, Fair Value Measurement ● Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. ● Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liabilities. ● Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). The following fair value hierarchy table presents information about each major category of the Company’s financial assets and liabilities measured at fair value on a recurring basis (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value measurement at reporting date using ​ ​ Quoted prices in ​ ​ ​ ​ ​ ​ ​ ​ active markets ​ Significant other ​ Significant ​ ​ for identical ​ observable ​ unobservable ​ ​ assets ​ inputs ​ inputs ​ (Level 1) (Level 2) (Level 3) December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents – money market fund ​ $ 41,561 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents – money market fund ​ $ 39,010 ​ $ — ​ $ —
Allowance for credit losses	Allowance for credit losses The following table presents a rollforward of the allowance of credit losses (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at Beginning of Period ​ Bad Debt Expense Recognized ​ Write-offs of Uncollectible Balances ​ ​ Balance at End of Period Year ended December 31, 2021 $ (46) ​ (12) ​ 6 ​ $ (52) Year ended December 31, 2022 $ (52) ​ (116) ​ 25 ​ $ (143) Year ended December 31, 2023 $ (143) ​ (306) ​ 33 ​ $ (416)
Net loss per share	Net loss per share Basic and diluted net loss per common share is determined by dividing net loss by the weighted-average shares of common stock outstanding during the reporting period. In periods in which the Company reports a net loss, diluted net loss per share is the same as basic net loss per share since dilutive shares are not assumed to have been issued if their effect is antidilutive. Therefore, the weighted-average shares used to calculate both basic and diluted loss per share are the same. The following potentially dilutive securities have been excluded from the computation of diluted weighted-average shares outstanding, as they would be antidilutive. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2023 ​ 2022 ​ 2021 Stock options (including shares subject to repurchase) ​ 2,162,453 2,071,848 ​ 1,706,438 Unvested restricted stock units ​ 907,203 ​ 311,991 ​ 163,043 Common stock warrants ​ 88,556 ​ 88,556 ​ 88,556 Total 3,158,212 2,472,395 ​ 1,958,037 ​
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments ​ In August 2020, the FASB issued ASU No. 2020-06, Debt with Conversion and Other Options and Derivatives and Hedging - Contracts in Entity’s Own Equity (“ . In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures interim period. The Company is currently evaluating the expected impact that the standard could have on its consolidated financial statements and related disclosures. ​ In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Summary of Significant Accounting Policies
Schedule of Inventory	Inventory consists of purchased materials, primarily finished goods and is identified and tracked by lot and stated at the lower of cost or net realizable value, with cost being determined on a first-in, first-out basis. Inventories consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Finished goods ​ $ 13,102 ​ $ 11,792 Raw materials ​ 60 ​ — Total inventory ​ $ 13,162 ​ $ 11,792 ​
Disaggregation of Revenue	The following table presents revenue disaggregated (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2023 ​ 2022 ​ 2021 OviTex ​ $ 39,416 ​ $ 28,879 ​ $ 22,990 OviTex PRS ​ ​ 18,736 ​ ​ 12,431 ​ ​ 6,473 Other ​ ​ 301 ​ ​ 108 ​ ​ — Total revenue ​ $ 58,453 ​ $ 41,418 ​ $ 29,463
Schedule of fair value of assets and liabilities measured on recurring basis	The following fair value hierarchy table presents information about each major category of the Company’s financial assets and liabilities measured at fair value on a recurring basis (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value measurement at reporting date using ​ ​ Quoted prices in ​ ​ ​ ​ ​ ​ ​ ​ active markets ​ Significant other ​ Significant ​ ​ for identical ​ observable ​ unobservable ​ ​ assets ​ inputs ​ inputs ​ (Level 1) (Level 2) (Level 3) December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents – money market fund ​ $ 41,561 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents – money market fund ​ $ 39,010 ​ $ — ​ $ —
Schedule of allowance for credit losses	The following table presents a rollforward of the allowance of credit losses (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at Beginning of Period ​ Bad Debt Expense Recognized ​ Write-offs of Uncollectible Balances ​ ​ Balance at End of Period Year ended December 31, 2021 $ (46) ​ (12) ​ 6 ​ $ (52) Year ended December 31, 2022 $ (52) ​ (116) ​ 25 ​ $ (143) Year ended December 31, 2023 $ (143) ​ (306) ​ 33 ​ $ (416)
Schedule of dilutive securities excluded	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2023 ​ 2022 ​ 2021 Stock options (including shares subject to repurchase) ​ 2,162,453 2,071,848 ​ 1,706,438 Unvested restricted stock units ​ 907,203 ​ 311,991 ​ 163,043 Common stock warrants ​ 88,556 ​ 88,556 ​ 88,556 Total 3,158,212 2,472,395 ​ 1,958,037

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property and Equipment
Schedule of Property and Equipment	Property and equipment consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, Asset description Estimated useful lives 2023 2022 Lab equipment 5 Years ​ $ 2,883 ​ $ 2,635 Furniture and fixtures 5 Years ​ 284 ​ 274 Computer equipment and software 3 Years ​ 645 ​ 604 Leasehold improvements Lesser of useful life or lease term ​ 2,507 ​ 2,309 Total ​ 6,319 ​ 5,822 Less accumulated depreciation and amortization ​ (4,335) ​ (4,140) Property and equipment, net ​ $ 1,984 ​ $ 1,682

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2023
Accrued Expenses and Other Current Liabilities
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Compensation and related benefits ​ $ 9,216 ​ $ 6,420 Third-party and professional fees ​ 2,828 ​ 2,563 Amounts due to contract manufacturer ​ ​ 2,024 ​ ​ 1,263 Current portion of operating lease liabilities ​ ​ 565 ​ ​ 340 Research and development expenses ​ ​ 140 ​ ​ 137 Other ​ 527 ​ 146 Total accrued expenses and other current liabilities ​ $ 15,300 ​ $ 10,869 ​

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2023
Debt
Schedule of long term debt	Long-term debt consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 MidCap Term Loan ​ $ 40,000 ​ $ 40,000 End of term charge ​ 2,000 ​ 2,000 Unamortized end of term charge and issuance costs ​ (1,485) ​ (2,084) Long-term debt ​ $ 40,515 ​ $ 39,916

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity
Schedule of warrants outstanding to purchase common stock	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Exercise ​ Expiration ​ Outstanding ​ price dates Common stock warrants 8,379 ​ $ 28.65 2028 Common stock warrants 80,177 ​ 28.65 2027 ​ 88,556 ​ ​ ​ ​ ​ ​

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Stock-Based Compensation
Schedule of stock based compensation expense categories in statement of operations	The Company recorded stock-based compensation expense in the following expense categories of its accompanying consolidated statements of operations and comprehensive loss (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2023 ​ 2022 ​ 2021 Sales and marketing ​ $ 1,824 ​ $ 1,373 ​ $ 961 General and administrative ​ 2,478 ​ 2,029 ​ 1,542 Research and development ​ 730 ​ 587 ​ 1,158 Total stock‑based compensation ​ $ 5,032 ​ $ 3,989 ​ $ 3,661
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ average ​ ​ ​ ​ Weighted ​ remaining ​ ​ Number of ​ average exercise ​ contractual term ​ shares price per share (years) Outstanding at January 1, 2021 1,498,208 ​ $ 10.87 Granted 468,000 ​ 14.80 Exercised (77,154) ​ 7.08 Canceled/forfeited (182,645) ​ 13.08 Outstanding at December 31, 2021 1,706,409 ​ $ 11.88 ​ Granted 450,410 ​ 10.24 Exercised (3,563) ​ 5.51 Canceled/forfeited (81,408) ​ 13.13 Outstanding at December 31, 2022 ​ 2,071,848 ​ $ 11.49 ​ ​ Granted ​ 212,960 ​ ​ 10.50 ​ ​ Exercised ​ (25,428) ​ ​ 5.00 ​ ​ Canceled/forfeited ​ (96,927) ​ ​ 11.25 ​ ​ Outstanding at December 31, 2023 ​ 2,162,453 ​ $ 11.48 ​ 6.26 Vested and expected to vest at December 31, 2023 2,131,840 ​ $ 11.48 6.23 Exercisable at December 31, 2023 1,606,779 ​ $ 11.50 5.50
Schedule of activity relating to early exercise of stock options	​ ​ ​ ​ ​ ​ Number of ​ shares Unvested balance at January 1, 2021 182 Vested (153) Unvested balance at December 31, 2021 ​ 29 Vested ​ (29) Unvested balance at December 31, 2022 —
Schedule of weighted average assumptions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2023 ​ 2022 2021 ​ Expected dividend yield — ​ — ​ — ​ Expected volatility 74.3 % 69.6 % 63.9 % Risk‑free interest rate 3.99 % 2.55 % 0.99 % Expected term (in years) 6.15 ​ 6.20 ​ 6.15 ​
Schedule of restricted stock units (RSUs)	​ ​ ​ ​ ​ ​ Number of ​ shares Outstanding at January 1, 2021 ​ — Granted ​ 194,232 Vested ​ (12,000) Canceled/forfeited ​ (19,189) Outstanding at December 31, 2021 ​ 163,043 Granted ​ 197,950 Vested ​ (40,783) Canceled/forfeited ​ (8,219) Outstanding at December 31, 2022 ​ 311,991 Granted ​ 729,734 Vested ​ (101,559) Canceled/forfeited ​ (32,963) Outstanding at December 31, 2023 ​ 907,203

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Taxes
Summary of Significant components of the Company's deferred tax assets	Significant components of the Company’s deferred tax assets for federal income taxes consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Deferred tax assets ​ ​ ​ ​ ​ Net operating loss carryforwards ​ $ 61,427 ​ $ 55,091 Interest expense carryforward ​ ​ 523 ​ ​ — Research and development credits ​ 830 ​ 623 Lease liability ​ ​ 557 ​ ​ 387 Capitalized research and development expenses ​ ​ 4,845 ​ ​ 1,743 Accrued expenses and other ​ 3,535 ​ 2,682 Inventory reserve ​ 289 ​ 372 Gross deferred tax asset ​ 72,006 ​ 60,898 Deferred tax liabilities ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ (436) ​ (435) Right of use asset ​ ​ (484) ​ ​ (302) Gross deferred tax liability ​ (920) ​ ​ (737) Net deferred tax asset before valuation allowance ​ ​ 71,086 ​ ​ 60,161 Valuation allowance ​ (71,086) ​ (60,161) Net deferred tax asset ​ $ — ​ $ —
Schedule of Company's net operating loss (NOL) carryforwards	The Company’s net operating loss (“NOL”) carryforwards for federal and state income tax purposes consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 NOL carryforwards ​ ​ ​ ​ ​ ​ Federal ​ $ 239,417 ​ $ 212,314 State ​ 196,132 ​ 173,472
Schedule of reconciliation of income tax benefit	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2023 2022 2021 ​ Rate reconciliation ​ ​ ​ ​ ​ Federal tax benefit at statutory rate (21.0) % (21.0) % (21.0) % State rate, net of federal benefit (3.1) (3.1) ​ (3.5) ​ Permanent differences 0.7 0.6 ​ 0.2 ​ Research and development (0.4) — ​ 0.4 ​ Change in valuation allowance 23.4 23.4 ​ 24.2 ​ Other 0.4 0.1 ​ (0.3) ​ Total tax provision — % — % — %

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of future minimum lease payments under non-cancelable operating lease agreement	The following table reconciles the undiscounted future minimum lease payments (displayed in aggregate by year) under non-cancelable operating leases with terms of more than one year to the total operating lease liabilities recognized on the consolidated balance sheets as of December 31, 2023 (in thousands): ​ ​ ​ ​ 2024 $ 601 2025 580 2026 ​ 557 2027 ​ 570 2028 ​ 583 Thereafter ​ 845 Total undiscounted future minimum lease payments $ 3,736 Less imputed interest ​ (1,486) Total operating lease liabilities $ 2,250

Risks and Liquidity (Details)

Risks and Liquidity (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended			12 Months Ended
	Apr. 21, 2023	Mar. 31, 2024	Apr. 30, 2023	Aug. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Unusual Risk or Uncertainty [Line Items]
Accumulated deficit					$ (320,889)	$ (274,225)
Received net proceeds of after deducting underwriting discounts, commissions and other offering expenses					$ 46,341	$ 34,400
Subsequent Event | MiMedx Group, Inc.
Unusual Risk or Uncertainty [Line Items]
Initial payment		$ 5,000
Period of net sales considered for calculating additional future payment receivable		2 years
Subsequent Event | MiMedx Group, Inc. | Maximum
Unusual Risk or Uncertainty [Line Items]
Aggregate additional future payments		$ 7,000
Subsequent Event | MiMedx Group, Inc. | Minimum
Unusual Risk or Uncertainty [Line Items]
Aggregate additional future payments		$ 3,000
Underwritten public offering
Unusual Risk or Uncertainty [Line Items]
Common stock issued and sold (in shares)	5,219,190		5,219,190
Offering price (in dollar per share)	$ 9.50		$ 9.50
Received net proceeds of after deducting underwriting discounts, commissions and other offering expenses	$ 46,300		$ 46,300
Over-Allotment Option
Unusual Risk or Uncertainty [Line Items]
Common stock issued and sold (in shares)	469,190		469,190	4,600,000
Offering price (in dollar per share)				$ 8
Received net proceeds of after deducting underwriting discounts, commissions and other offering expenses				$ 34,400

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Segments (Details)	12 Months Ended
	Dec. 31, 2023 segment
Segments
Number of segments	1

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Inventory
Finished goods	$ 13,102	$ 11,792
Raw materials	60
Total inventory	13,162	11,792
Inventory consigned to others	$ 3,000	$ 2,300

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Intangible Assets
Amortization expense related to intangible assets	$ 380	$ 804	$ 304
Remaining life of intangible assets	5 years 7 months 6 days
Intangible assets future amortization
Year 1	$ 400
Year 2	400
Year 3	400
Year 4	400
Year 5	400
Thereafter	$ 100

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Long-Lived Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Long-Lived Assets
Impairment of long-lived assets	$ 0	$ 0	$ 0

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Revenue Disaggregated (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 58,453	$ 41,418	$ 29,463
Incremental costs of obtaining a contract	0
Non-US [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 6,100	$ 3,200
Revenue, as a percentage	10%	8%
OviTex
Disaggregation of Revenue [Line Items]
Revenue	$ 39,416	$ 28,879	22,990
OviTex PRS
Disaggregation of Revenue [Line Items]
Revenue	18,736	12,431	$ 6,473
Other
Disaggregation of Revenue [Line Items]
Revenue	$ 301	$ 108

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Fair value of financial instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Recurring | Level 1 | Money market funds
Fair value of financial instruments
Cash equivalents	$ 41,561	$ 39,010

Summary of Significant Accou_10

Summary of Significant Accounting Policies - Allowance for credit losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Roll forward of allowance for credit loss
Balance at Beginning of Period	$ (143)	$ (52)	$ (46)
Bad Debt Expense Recognized	(306)	(116)	(12)
Write-offs of Uncollectible Balances	33	25	6
Balance at End of Period	$ (416)	$ (143)	$ (52)

Summary of Significant Accou_11

Summary of Significant Accounting Policies - Net loss per share (Potentially dilutive securities) (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Potentially dilutive securities
Potentially dilutive securities excluded from computation of diluted weighted average shares	3,158,212	2,472,395	1,958,037
Employee Stock Option
Potentially dilutive securities
Potentially dilutive securities excluded from computation of diluted weighted average shares	2,162,453	2,071,848	1,706,438
Restricted stock units
Potentially dilutive securities
Potentially dilutive securities excluded from computation of diluted weighted average shares	907,203	311,991	163,043
Common Stock Warrants
Potentially dilutive securities
Potentially dilutive securities excluded from computation of diluted weighted average shares	88,556	88,556	88,556

Property and Equipment (Details

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property and Equipment
Property and Equipment, Total	$ 6,319	$ 5,822
Less accumulated depreciation and amortization	(4,335)	(4,140)
Property and equipment, net	1,984	1,682
Depreciation expense	428	383	$ 231
Umbrella Agreement with Aroa
Property and Equipment
Property and Equipment, Total	200	200
Lab equipment
Property and Equipment
Property and Equipment, Total	$ 2,883	2,635
Estimated useful lives	5 years
Furniture and fixtures
Property and Equipment
Property and Equipment, Total	$ 284	274
Estimated useful lives	5 years
Computer equipment and software
Property and Equipment
Property and Equipment, Total	$ 645	604
Estimated useful lives	3 years
Leasehold improvements
Property and Equipment
Property and Equipment, Total	$ 2,507	$ 2,309

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued Expenses and Other Current Liabilities
Compensation and related benefits	$ 9,216	$ 6,420
Third-party and professional fees	2,828	2,563
Amounts due to contract manufacturer	2,024	1,263
Current portion of operating lease liabilities	$ 565	$ 340
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total accrued expenses and other current liabilities	Total accrued expenses and other current liabilities
Research and development expenses	$ 140	$ 137
Other	527	146
Total accrued expenses and other current liabilities	$ 15,300	$ 10,869

Debt - Schedule of long term de

Debt - Schedule of long term debt (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	May 26, 2022
Long term Debt
End of term charge	$ 2,000	$ 2,000
Unamortized end of term charge and issuance costs	(1,485)	(2,084)
Long-term debt	40,515	39,916
MidCap Term Loan
Long term Debt
Long Term Debt	$ 40,000	$ 40,000	$ 50,000

Debt - MidCap Term Loan (Detail

Debt - MidCap Term Loan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	May 26, 2022
MidCap Term Loan
Long term Debt
Debt amount	$ 40,000,000	$ 40,000,000	$ 50,000,000
Interest due to unpaid obligation	2%
Interest Rate (as a percent)	6.25%
Interest-Only Period	36 months
Exit fee (as a percent)	5%
Interest expenses	$ 5,200,000	2,600,000
Amortization of debt issuance costs	$ 600,000	$ 400,000
MidCap Term Loan | Maximum
Long term Debt
Extension for interest only payment period	48 months
MidCap Term Loan | Minimum
Long term Debt
Extension for interest only payment period	12 months
MidCap Term Loan | First year
Long term Debt
Percentage Of Prepayment Penalty On Prepaid Principal Amount 3	3%
MidCap Term Loan | Second year
Long term Debt
Percentage Of Prepayment Penalty On Prepaid Principal Amount 2	2%
MidCap Term Loan | Third year
Long term Debt
Percentage of prepayment penalty on prepaid principal amount	1%
MidCap Term Loan | SOFR
Long term Debt
Variable Interest Rate (as a percent)	1%
Tranche One
Long term Debt
Debt amount			40,000,000
Tranche Two
Long term Debt
Debt amount	$ 0		$ 10,000,000

Debt - OrbiMed Term Loan (relat

Debt - OrbiMed Term Loan (related party) (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2018 USD ($) tranche	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Long term Debt
Loss on extinguishment of debt			$ (1,228)
OrbiMed Term Loans (related party)
Long term Debt
Debt amount	$ 35,000
Number of Tranches | tranche	2
Interest Rate (as a percent)		7.75%
End of Term Charge		$ 3,000
Loss on extinguishment of debt			1,200
Interest expenses			1,500	$ 3,600
Amortization of debt issuance costs			$ 300	$ 700
OrbiMed Term Loans (related party) | Applicable Rate [Member]
Long term Debt
Variable Interest Rate (as a percent)		2%
OrbiMed Term Loans - Tranche One
Long term Debt
Debt amount	$ 30,000
OrbiMed Term Loans - Tranche Two
Long term Debt
Debt amount	$ 5,000

Stockholders' Equity - Public S

Stockholders' Equity - Public Stock Offerings (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		12 Months Ended
	Apr. 21, 2023	Apr. 30, 2023	Aug. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Nov. 30, 2023
Stockholders' Equity
Received net proceeds of after deducting underwriting discounts, commissions and other offering expenses				$ 46,341	$ 34,400
Over-Allotment Option
Stockholders' Equity
Common stock issued and sold (in shares)	469,190	469,190	4,600,000
Offering price (in dollar per share)			$ 8
Received net proceeds of after deducting underwriting discounts, commissions and other offering expenses			$ 34,400
Underwritten public offering
Stockholders' Equity
Common stock issued and sold (in shares)	5,219,190	5,219,190
Offering price (in dollar per share)	$ 9.50	$ 9.50
Received net proceeds of after deducting underwriting discounts, commissions and other offering expenses	$ 46,300	$ 46,300
Equity Distribution Agreement
Stockholders' Equity
Common Stock Available Under ATM							$ 50,000
Value Of Shares Sold Under Equity Distribution Agreement				$ 0	$ 0	$ 0

Stockholders' Equity - Warrants

Stockholders' Equity - Warrants outstanding (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Stockholders' Equity
Warrants outstanding	88,556
Common stock warrants expiring in 2028
Stockholders' Equity
Warrants outstanding	8,379
Warrants exercise price | $ / shares	$ 28.65
Expiration dates	2028
Common stock warrants expiring in 2027
Stockholders' Equity
Warrants outstanding	80,177
Warrants exercise price | $ / shares	$ 28.65
Expiration dates	2027

Stock-Based Compensation - Narr

Stock-Based Compensation - Narratives (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) item $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares
Stock-Based Compensation
Number of equity incentive plans | item	2
Aggregate intrinsic value of exercisable options | $	$ 100,000	$ 16,000	$ 400,000
Employee Stock Option [Member]
Stock-Based Compensation
Weighted average grant date fair value, Options (per share) | $ / shares	$ 7.19	$ 6.55	$ 8.66
Inducement grants of Stock Options	355,766
Aggregate intrinsic value of outstanding options | $	$ 300,000
Unrecognized compensation expense | $	$ 3,500,000
Weighted average period for recognition of unrecognized expenses	2 years 2 months 12 days
Restricted stock units
Stock-Based Compensation
Weighted average grant date fair value, Equity Instruments (per share) | $ / shares	$ 10.25	$ 11.21	$ 16.57
Aggregate intrinsic value | $	$ 6,000,000	$ 3,600,000
Unrecognized compensation expense | $	$ 4,800,000
Weighted average period for recognition of unrecognized expenses	2 years 10 months 24 days
Granted	729,734	197,950	194,232
Performance based restricted stock units
Stock-Based Compensation
Weighted average grant date fair value, Equity Instruments (per share) | $ / shares	$ 10.95
Inducement grants	123,250
Granted	250,149
Performance based restricted stock units | Minimum
Stock-Based Compensation
Vest Range	0%
Performance based restricted stock units | Maximum
Stock-Based Compensation
Vest Range	110%
Service based restricted stock unit
Stock-Based Compensation
Vesting period	4 years
Weighted average grant date fair value, Equity Instruments (per share) | $ / shares	$ 9.89
Granted	479,585
2019 Equity Incentive Plan
Stock-Based Compensation
Shares available for future issuance	1,138,279
Common Stock Capital Shares Reserved For Future Annual Issuance	432,442
Common Stock Capital Shares Reserved For Future Issuance, Percentage Of Shares Outstanding Last Day Of Fiscal Year	4%
Vesting period	4 years
Contractual term	10 years

Stock-Based Compensation - Expe

Stock-Based Compensation - Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock-Based Compensation
Total stock-based compensation	$ 5,032	$ 3,989	$ 3,661
Sales and marketing
Stock-Based Compensation
Total stock-based compensation	1,824	1,373	961
General and administrative
Stock-Based Compensation
Total stock-based compensation	2,478	2,029	1,542
Research and development
Stock-Based Compensation
Total stock-based compensation	$ 730	$ 587	$ 1,158

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Number of shares
Balance at beginning of period	2,071,848	1,706,409	1,498,208
Granted	212,960	450,410	468,000
Exercised	(25,428)	(3,563)	(77,154)
Canceled/forfeited	(96,927)	(81,408)	(182,645)
Balance at end of period	2,162,453	2,071,848	1,706,409
Vested and expected to vest at end of period	2,131,840
Exercisable at end of period	1,606,779
Weighted average exercise price per share
Balance at beginning of period (in dollars per share)	$ 11.49	$ 11.88	$ 10.87
Granted ( in dollars per share)	10.50	10.24	14.80
Exercised (in dollars per share)	5	5.51	7.08
Canceled/forfeited (in dollars per share)	11.25	13.13	13.08
Balance at end of period (in dollars per share)	11.48	$ 11.49	$ 11.88
Vested and expected to vest at end of period (in dollars per share)	11.48
Exercisable at end of period (in dollars per share)	$ 11.50
Weighted average remaining contractual term (years)
Weighted average remaining contractual term, outstanding	6 years 3 months 3 days
Weighted average remaining contractual term, Vested and expected to vest	6 years 2 months 23 days
Weighted average remaining contractual term, Exercisable	5 years 6 months

Stock-Based Compensation - Earl

Stock-Based Compensation - Early Exercise Of Stock Options (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Stock-Based Compensation
Early exercised stock options, Unvested balance at beginning of period	29	182
Vested	(29)	(153)
Early exercised stock options, Unvested balance at end of period		29

Stock-Based Compensation - Weig

Stock-Based Compensation - Weighted average assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock-Based Compensation
Expected dividend yield	0%	0%	0%
Expected volatility	74.30%	69.60%	63.90%
Risk-free interest rate	3.99%	2.55%	0.99%
Expected term (in years)	6 years 1 month 24 days	6 years 2 months 12 days	6 years 1 month 24 days

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Details) - Restricted stock units - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Outstanding at beginning of period	311,991	163,043
Granted	729,734	197,950	194,232
Vested	(101,559)	(40,783)	(12,000)
Canceled/forfeited	(32,963)	(8,219)	(19,189)
Outstanding at end of period	907,203	311,991	163,043

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 2019	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Contribution Plan Disclosure [Line Items]
Maximum contribution of participant (as a percent)		100%
Percentage of employer's contribution		50%
Percentage of employer's contribution to employees		6%
Amount of employer's contribution		$ 0.5	$ 0.4	$ 0.3
Deferred Compensation Arrangement with Individual, Requisite Service Period		3 years
Employee Stock Purchase Plan 2019
Defined Contribution Plan Disclosure [Line Items]
Shares reserved for future issuance		518,350
Increase in number of shares	107,887
Increase in percentage of shares outstanding	1%
Discount on purchase of common stock		15%
Shares issued		10,602	4,523	3,163

Income Taxes - Deferred tax ass

Income Taxes - Deferred tax assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets
Net operating loss carryforwards	$ 61,427	$ 55,091
Interest expense carryforward	523
Research and development credits	830	623
Lease liability	557	387
Capitalized research and development expenses	4,845	1,743
Accrued expenses and other	3,535	2,682
Inventory reserve	289	372
Gross deferred tax asset	72,006	60,898
Deferred tax liabilities
Depreciation and amortization	(436)	(435)
Right of use asset	(484)	(302)
Gross deferred tax liability	(920)	(737)
Net deferred tax asset before valuation allowance	71,086	60,161
Valuation allowance	(71,086)	(60,161)
Net deferred tax asset	$ 0	$ 0

Income Taxes - NOL carryforward

Income Taxes - NOL carryforwards (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Federal
Income Taxes
NOL carryforwards	$ 239,417	$ 212,314
Deferred tax assets, operating loss carryforwards, not subject to expiration	160,000
State
Income Taxes
NOL carryforwards	$ 196,132	$ 173,472

Income Taxes - Rate reconciliat

Income Taxes - Rate reconciliation (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Rate reconciliation
Federal tax benefit at statutory rate	(21.00%)	(21.00%)	(21.00%)
State rate, net of federal benefit	(3.10%)	(3.10%)	(3.50%)
Permanent differences	0.7	0.6	0.2
Research and development	(0.40%)		0.40%
Change in valuation allowance	23.40%	23.40%	24.20%
Other	0.40%	0.10%	(0.30%)
Total tax provision

Income Taxes - Narratives (Deta

Income Taxes - Narratives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Unrecognized tax benefits	$ 0	$ 0
Increase (decrease) in valuation allowance	$ 10,900	$ 10,400

Commitments and Contingencies_2

Commitments and Contingencies (Details) $ in Thousands		1 Months Ended		12 Months Ended
	Jun. 30, 2025 ft²	Oct. 31, 2023 USD ($) ft²	Aug. 31, 2012 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 01, 2023 ft²	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Contingencies and Commitments
Operating lease cost				$ 300	$ 300
Operating lease payments made				400	300
Operating Lease, Liability, Current				$ 565	$ 340
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]				Accrued Liabilities, Current	Accrued Liabilities, Current
Operating Lease, Liability, Noncurrent				$ 1,700
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]				Other Liabilities, Noncurrent
Lease Amendment
Contingencies and Commitments
Additional space leased | ft²		15,881
Lease space relinquished | ft²	4,652
Area (sqft) | ft²	35,954	24,725				40,606
Additional security deposit		$ 300
Pennsylvania | Office and laboratory space
Contingencies and Commitments
Lessee, Operating Lease, Existence of Option to Extend [true false]				true
Renewal term of operating lease				60 months
Incremental borrowing rate						11.66%
Remaining lease term				6 years 4 months 24 days
Umbrella Agreement with Aroa
Contingencies and Commitments
Payment for agreement			$ 4,000
Milestone payments related to research and development arrangements				$ 1,800
Fixed Cost Of Net Sales				27%
Number of days for product supply				60 days
Percentage of products ordered to be supplied				75%
Royalty percentage of net sales				6%
Umbrella Agreement with Aroa | European territory
Contingencies and Commitments
Sales milestone payments due					$ 1,000
Umbrella Agreement with Aroa | North American territory
Contingencies and Commitments
Sales milestone payment							$ 2,000	$ 1,000
Transfer Price For Product Produced				200%
Transfer price for product produced for use in IHR				150%
Fixed Cost Of Net Sales				27%
Other Suppliers for Exclusivity Rights [Member]
Contingencies and Commitments
Payments To Maintain Exclusivity				$ 7,100

Commitments and Contingencies -

Commitments and Contingencies - Operating Leases (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Leases, Operating [Abstract]
2024	$ 601
2025	580
2026	557
2027	570
2028	583
Thereafter	845
Total undiscounted future minimum lease payments	3,736
Less imputed interest	(1,486)
Total operating lease liabilities	$ 2,250

Subsequent Event (Details)

Subsequent Event (Details) - Subsequent Event - MiMedx Group, Inc $ in Millions	1 Months Ended
	Mar. 31, 2024 USD ($)
Subsequent Event
Initial payment	$ 5
Period of net sales considered for calculating additional future payment receivable	2 years
Minimum
Subsequent Event
Aggregate additional future payments	$ 3
Maximum
Subsequent Event
Aggregate additional future payments	$ 7

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net Income (Loss)	$ (46,664)	$ (44,296)	$ (33,276)

Insider Trading Arrangements

Insider Trading Arrangements	12 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false