Vericel (VCEL) 10-Q 4 May 22 2022 Q1 Quarterly report Financial data

Cover

Cover - shares	3 Months Ended
	Mar. 31, 2022	Apr. 29, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	001-35280
Entity Registrant Name	VERICEL CORPORATION
Entity Incorporation, State or Country Code	MI
Entity Tax Identification Number	94-3096597
Entity Address, Address Line One	64 Sidney Street
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02139
City Area Code	617
Local Phone Number	588-5555
Title of 12(b) Security	Common Stock (No par value)
Trading Symbol	VCEL
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		47,119,902
Entity Central Index Key	0000887359
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 55,659	$ 68,330
Short-term investments	44,888	35,068
Accounts receivable (net of allowance for doubtful accounts of $40 and $40, respectively)	31,855	37,437
Inventory	14,385	13,381
Other current assets	5,093	4,246
Total current assets	151,880	158,462
Property and equipment, net	14,451	13,308
Restricted cash	6,184	211
Right-of-use assets	44,653	45,720
Long-term investments	22,803	25,687
Other long-term assets	317	317
Total assets	240,288	243,705
Current liabilities:
Accounts payable	7,750	9,016
Accrued expenses	10,793	14,045
Current portion of operating lease liabilities	3,147	2,950
Other current liabilities	41	41
Total current liabilities	21,731	26,052
Operating lease liabilities	46,053	47,147
Other long-term liabilities	19	44
Total liabilities	67,803	73,243
COMMITMENTS AND CONTINGENCIES
Shareholders’ equity:
Common stock, no par value; shares authorized — 75,000; shares issued and outstanding 47,081 and 46,880, respectively	563,475	553,902
Accumulated other comprehensive loss	(613)	(154)
Accumulated deficit	(390,377)	(383,286)
Total shareholders’ equity	172,485	170,462
Total liabilities and shareholders’ equity	$ 240,288	$ 243,705

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 40	$ 40
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	47,081,000	46,880,000
Common stock, shares outstanding (in shares)	47,081,000	46,880,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Revenue, Product and Service [Extensible List]	Product [Member]
Product sales, net	$ 35,852	$ 33,627
Other revenue	222	941
Total revenue	$ 36,074	34,568
Cost, Product and Service [Extensible List]	Product [Member]
Cost of product sales	$ 12,622	11,583
Gross profit	23,452	22,985
Research and development	4,860	3,630
Selling, general and administrative	25,865	22,660
Total operating expenses	30,725	26,290
Loss from operations	(7,273)	(3,305)
Other income (expense):
Interest income	88	76
Interest expense	(18)	(1)
Other income	112	84
Total other income	182	159
Loss before income taxes	(7,091)	(3,146)
Income tax expense	0	143
Net loss	$ (7,091)	$ (3,289)
Net loss per common share:
Basic (in USD per share)	$ (0.15)	$ (0.07)
Diluted (in USD per share)	$ (0.15)	$ (0.07)
Weighted-average common shares outstanding:
Basic (in shares)	46,985	45,984
Diluted (in shares)	46,985	45,984

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net loss	$ (7,091)	$ (3,289)
Other comprehensive loss:
Unrealized loss on investments	(459)	(61)
Comprehensive loss	$ (7,550)	$ (3,350)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2020		45,804
Beginning balance at Dec. 31, 2020	$ 134,260	$ 510,061	$ 14	$ (375,815)
Increase (Decrease) in Shareholders' Equity
Net loss	(3,289)			(3,289)
Stock-based compensation expense	7,019	$ 7,019
Stock option exercises (in shares)		359
Stock option exercises	3,532	$ 3,532
Shares issued under the Employee Stock Purchase Plan (in shares)		14
Shares issued under the Employee Stock Purchase Plan	249	$ 249
Issuance of stock for restricted stock unit vesting (in shares)		76
Issuance of stock for restricted stock unit vesting	0
Restricted stock withheld for employee tax remittance (in shares)		(28)
Restricted stock withheld for employee tax remittance	(1,501)	$ (1,501)
Unrealized loss on investments	(61)		(61)
Ending balance (in shares) at Mar. 31, 2021		46,225
Ending balance at Mar. 31, 2021	140,209	$ 519,360	(47)	(379,104)
Beginning balance (in shares) at Dec. 31, 2021		46,880
Beginning balance at Dec. 31, 2021	170,462	$ 553,902	(154)	(383,286)
Increase (Decrease) in Shareholders' Equity
Net loss	(7,091)			(7,091)
Stock-based compensation expense	9,531	$ 9,531
Stock option exercises (in shares)		125
Stock option exercises	1,155	$ 1,155
Shares issued under the Employee Stock Purchase Plan (in shares)		9
Shares issued under the Employee Stock Purchase Plan	310	$ 310
Issuance of stock for restricted stock unit vesting (in shares)		108
Issuance of stock for restricted stock unit vesting	0
Restricted stock withheld for employee tax remittance (in shares)		(41)
Restricted stock withheld for employee tax remittance	(1,423)	$ (1,423)
Unrealized loss on investments	(459)		(459)
Ending balance (in shares) at Mar. 31, 2022		47,081
Ending balance at Mar. 31, 2022	$ 172,485	$ 563,475	$ (613)	$ (390,377)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net loss	$ (7,091)	$ (3,289)
Adjustments to reconcile net loss to net cash flows from operating activities:
Depreciation and amortization expense	873	811
Stock-based compensation expense	9,531	7,019
Amortization of premiums and discounts on marketable securities	194	273
Non-cash lease cost	1,076	1,171
Other	4	(20)
Changes in operating assets and liabilities:
Inventory	(1,004)	(966)
Accounts receivable	5,582	5,382
Other current assets	(847)	(320)
Accounts payable	(219)	2,174
Accrued expenses	(3,734)	(1,328)
Operating lease liabilities	(897)	(821)
Net cash provided by operating activities	3,468	10,086
Investing activities:
Purchases of investments	(12,629)	(10,426)
Sales and maturities of investments	5,041	24,955
Expenditures for property and equipment	(3,081)	(2,343)
Net cash (used in) provided by investing activities	(10,669)	12,186
Financing activities:
Net proceeds from common stock issuance	1,465	3,781
Payments on employee’s behalf for taxes related to vesting of restricted stock unit awards	(943)	(1,501)
Other	(19)	(18)
Net cash provided by financing activities	503	2,262
Net (decrease) increase in cash, cash equivalents, and restricted cash	(6,698)	24,534
Cash, cash equivalents, and restricted cash at beginning of period	68,541	33,831
Cash, cash equivalents, and restricted cash at end of period	61,843	58,365
Supplemental disclosure of cash flow information:
Additions to property and equipment included in accounts payable	317	530
Restricted stock held for employee tax remittance included in accounts payable	480	65
Reconciliation of amounts within the condensed consolidated balance sheets:
Cash and cash equivalents	55,659	58,154
Restricted cash	6,184	211
Total cash, cash equivalents, and restricted cash at end of period	$ 61,843	$ 58,365

Organization

Organization	3 Months Ended
	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Vericel Corporation, a Michigan corporation (together with its consolidated subsidiaries referred to herein as the Company, or Vericel), was incorporated in March 1989 and began employee-based operations in 1991. The Company is a fully-integrated, commercial-stage biopharmaceutical company and is a leader in advanced therapies for the sports medicine and severe burn care markets. Vericel currently markets two cell therapy products in the U.S., MACI ® (autologous cultured chondrocytes on porcine collagen membrane) and Epicel ® (cultured epidermal autografts). MACI is an autologous cellularized scaffold product indicated for the repair of symptomatic, single or multiple full-thickness cartilage defects of the knee with or without bone involvement in adults. Epicel is a permanent skin replacement for the treatment of adult and pediatric patients with deep-dermal or full-thickness burns comprising greater than or equal to 30 percent of total body surface area (“TBSA”). The Company also holds an exclusive license from MediWound Ltd. (“MediWound”) for North American rights to NexoBrid ® , a registration-stage biological orphan product designed for the debridement of severe thermal burns. The Company operates its business primarily in the U.S. in one reportable segment — the research, product development, manufacture and distribution of cellular therapies for use in the treatment of specific diseases. COVID-19 The ongoing pandemic caused by the spread of a novel strain of coronavirus (“COVID-19”) has created significant disruptions to the U.S. and global economy and has contributed to significant volatility in financial markets. The global impact of the outbreak has fluctuated since early 2020. At times, many state, local and national governments – including those in Massachusetts and Michigan, where the Company’s operations are located – have responded by issuing, extending and supplementing orders requiring quarantines, restrictions on travel, and the mandatory closure of certain non-essential businesses, among other actions. In the U.S., the status and application of these orders have varied on a state-by-state basis since the early days of the pandemic. Many of the restrictions have been periodically updated as infection rates in the U.S. have risen and fallen, as new virus variants have emerged, as vaccines have been distributed and administered, and as world health leaders learn more about the virus, its transmission pathway and who is most at risk. Because Vericel is deemed an essential business, the Company has been exempted from government orders requiring the closure of workplaces and the cessation of business operations. Notwithstanding being an essential business, the Company’s business and operations at times have been adversely impacted by the ongoing effects of the COVID-19 pandemic. For example, as a result of periodic restrictions placed on the performance of elective surgical procedures, Vericel experienced a significant increase in cancellations of scheduled MACI procedures as well as a slowdown in new MACI orders during March and April of 2020. The widespread suspension of surgical procedures impacted the Company’s business and operations during the first and second quarters of 2020. The level and degree of restriction on elective surgeries, on the ability of patients to seek treatment and on U.S. business operations generally fluctuated throughout 2020 as COVID-19 infection rates rose and fell during the summer months and into the autumn. By the first quarter of 2021, the pandemic’s effects on the Company’s MACI business had largely dissipated. During the summer of 2021, however, the pandemic’s direct and ancillary effects again began to cause some disruption to the Company’s MACI business. Following the cessation of COVID-19-related travel restrictions in many parts of the U.S. and the availability of vaccinations in May and June 2021, some MACI patients postponed or delayed treatment. Further, surges of new COVID-19 cases during the second half of 2021 caused by the spread of the “Delta” and “Omicron” variants again caused disruptions to health care networks including restrictions on the performance of elective procedures, the availability of physicians and/or their treatment prioritizations, the level of healthcare facility staffing and, in some instances, the willingness or ability of patients to seek treatment. Consequently, and notwithstanding the widespread distribution of vaccines, these factors contributed to a slowdown of MACI procedures during the third and fourth quarters of 2021 and during the first months of 2022. Although hospitals are now better prepared for subsequent surges in COVID-19 patients, the risk remains that regional or local restrictions could again be placed on the performance of elective surgical procedures if the number of COVID-19 infections in the U.S. were to rise, or if new or existing COVID-19 variants render current vaccine treatments ineffective. Because Epicel is used almost exclusively in an emergent setting by burn centers and surgeons throughout the country, Epicel revenue and procedure volumes have been less affected by the pandemic. Nevertheless, the number of large burns and burn admissions can be affected by restrictions on human activity resulting from more severe government lockdown orders. At the outset of the pandemic, the Company put in place a comprehensive workplace protection plan, which instituted protective measures in response to COVID-19. Vericel’s workplace protection plan has closely followed guidance issued by the Centers for Disease Control and Prevention (“CDC”) and has complied with applicable federal and state law. To date, Vericel has been successful in sustaining its operations and providing MACI and Epicel to patients in need. The Company continues to review its policies and procedures regularly, including its workplace protection plan, as the pandemic evolves and the Company may take additional actions to the extent required. The Company continues to manufacture MACI and Epicel and is maintaining a significant safety stock of all key raw materials. Vericel does not expect current supply chain interruptions will impact its ongoing manufacturing operations. With respect to customer delivery, MACI final product has an established shelf life of six (6) days and an established shipping shelf life of three (3) days. Currently, MACI is picked up by courier and shipped by commercial air or ground transportation to customer surgical sites. Epicel final product has an established shelf life of 48 hours and is hand carried to customer hospitals by courier. Transportation is primarily by commercial or charter airline. Although the Company has not experienced material shipping delays or materially increased costs to date, significant disruption of air travel could result in the inability to deliver MACI or Epicel final products to customer sites within appropriate timeframes, which could further adversely impact the Company’s business. At this time, the Company is not aware of COVID-19 related impacts on its distributors, operations or third-party service providers’ ability to manage patient cases. The Company believes it is possible that it could experience variable impacts on our business, should a new resurgence of COVID-19 infections occur in the future. Liquidity The accompanying condensed consolidated financial statements have been prepared on a basis which assumes that the Company will continue as a going concern and contemplates the realization of assets and the satisfaction of liabilities and commitments in the normal course of business. As of March 31, 2022, the Company had an accumulated deficit of $390.4 million and had a net loss of $7.1 million during the three months ended March 31, 2022. The Company had cash and cash equivalents of $55.7 million and investments of $67.7 million as of March 31, 2022. The Company expects that cash from the sales of its products and existing cash, cash equivalents and investments will be sufficient to support the Company’s current operations through at least 12 months from the issuance of these condensed consolidated financial statements. The effects of the COVID-19 pandemic continue to evolve, however. To the extent the U.S. experiences a worsening in COVID-19 infections or the emergence of additional virus variants that result in more serious disease or limit the effectiveness of existing vaccines, subsequent healthcare measures – to include the postponement or cessation of elective and other surgical procedures – may cause the Company to experience a reduction in business and resulting revenue. This, consequently, may result in irrecoverable losses of customers and significantly impact the Company’s long-term liquidity, potentially requiring the Company to engage in layoffs, furloughs and/or reductions in salaries. The Company also may need to access additional capital; however, the Company may not be able to obtain financing on acceptable terms or at all, particularly in light of the impact of COVID-19 on the global economy and financial markets. The terms of any financing may adversely affect the holdings or the rights of the Company’s shareholders.

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying c ondensed consolidated financial statements of Vericel are unaudited and have been prepared in accordance with the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). The preparation of condensed consolidated financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates, judgments, and assumptions that may affect the reported amounts of assets, liabilities, equity, revenue and expenses. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been omitted pursuant to such rules and regulations. The financial statements reflect, in the opinion of management, all adjustments (consisting only of normal, recurring adjustments) necessary to state fairly the financial position and results of operations as of and for the periods indicated. The Company bases its estimates on historical experience and on various other assumptions that it believes are reasonable, the results of which form the basis for making judgments about the carrying values of assets, liabilities and equity and the amount of revenue and expenses. The full extent to which the COVID-19 pandemic will continue to directly or indirectly impact its business, results of operations and financial condition, including sales, expenses, reserves and allowances, manufacturing, clinical trials, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning the COVID-19 pandemic and the actions taken to continue to contain or treat COVID-19, as well as the economic impact on its customers. The Company has made estimates of the impact of the COVID-19 pandemic within these financial statements and there may be changes to those estimates in future periods. Actual results may differ from these estimates. As of March 31, 2022, the Company has not recorded impairments to investments, inventory, other current assets or long-lived assets as a result of the COVID-19 pandemic. The condensed consolidated balance sheet at December 31, 2021 has been derived from the audited consolidated financial statements at that date, but does not include all the information and notes required by U.S. GAAP for complete financial statements. These c ondensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2021, as filed with the SEC on February 24, 2022 (“Annual Report”). Recent Accounting Pronouncements No new Accounting Standards were adopted during the quarter ended March 31, 2022.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2022
Risks and Uncertainties [Abstract]
Revenue	Revenue Revenue Recognition and Net Product Sales The Company recognizes product revenue from sales of MACI biopsy kits, MACI implants, Epicel grafts and other sources following the five-step model in Accounting Standards Codification 606, Revenue Recognition. MACI Biopsy Kits MACI biopsy kits are sold directly to hospitals and ambulatory surgical centers based on contracted rates in an approved contract or sales order. The Company recognizes MACI kit revenue upon delivery of the biopsy kit, at which time the customer (the facility) is in control of the kit. The kit is used by the doctor to provide a sample of cartilage tissue to the Company, which can later be used to manufacture a MACI implant. The ordering of the kit does not obligate the Company to manufacture an implant nor does the receipt of the cartilage tissue by the Company from the customer following biopsy. The customer’s order of an implant is separate from the process of ordering the biopsy kit. Therefore, the sale of the biopsy kit and any subsequent sale of an implant are distinct contracts and are accounted for separately. MACI Implants The Company contracts with two specialty pharmacies, Orsini Pharmaceutical Services, Inc. (“Orsini”) and AllCare Plus Pharmacy, Inc. (“AllCare”) to distribute MACI in a manner in which the Company retains the credit and collection risk from the end customer. The Company pays both specialty pharmacies a fee for each patient to whom MACI is dispensed. Both Orsini and AllCare perform collection activities to collect payment from customers. The Company engages a third party to provide services in connection with a patient support program to manage patient cases and to ensure complete and correct billing information is provided to the insurers and hospitals. In addition, the Company also sells MACI directly to DMS Pharmaceutical Group, Inc.(“DMS”) for patients treated at military treatment facilities. The sales directly to DMS are made at a contracted rate. Prior authorization and confirmation of coverage level by the patient’s private insurance plan, hospital or government payer is a prerequisite to the shipment of product to a patient. The Company recognizes product revenue from sales of all MACI implants upon delivery at which time the customer obtains control of the implant and the claim is billable. The total consideration which the Company expects to collect in exchange for MACI implants (the “Transaction Price”) may be fixed or variable. Direct sales to hospitals or distributors are recorded at a contracted price, and there are typically no forms of variable consideration. When the Company sells MACI, the patient is responsible for payment; however, the Company is typically reimbursed by a third-party insurer or government payer, subject to a patient co-pay amount. Reimbursements from third-party insurers and government payers vary by patient and payer and are based on either contracted rates, publicly available rates, fee schedules or past payer precedents. Net product revenue is recognized net of estimated contractual allowances, which considers historical collection experience from both the payer and patient, denial rates and the terms of the Company’s contractual arrangements. The Company estimates expected collections for these transactions using the portfolio approach. The Company records a reduction to revenue at the time of sale for its estimate of the amount of consideration that will not be collected. In addition, potential credit risk exposure has been evaluated for the Company’s accounts receivable in accordance with ASC 326, Financial Instruments - Credit Losses . The Company assesses risk and determines a loss percentage by pooling account receivables based on similar risk characteristics. The loss percentage is calculated through the use of forecasts that are based on current and historical economic and financial information. This loss percentage was applied to the accounts receivables as of March 31, 2022. The total allowance for uncollectible consideration as of March 31, 2022 and December 31, 2021 was $6.7 million and $7.0 million, respectively. Changes to the estimate of the amount of consideration that will not be collected could have a material impact on the revenue recognized. A 50 basis points change to the estimated uncollectible percentage could result in an approximately $0.3 million decrease or increase in the revenue recognized for the three months ended March 31, 2022. Changes in estimates of the Transaction Price are recorded through revenue in the period in which such change occurs. Changes in estimates related to prior periods are shown in the Revenue by Product and Customer table below and relate primarily to changes in the initial expected reimbursement or collection expectation upon completion of the billing claims process for MACI implants that occurred in a prior year. Epicel The Company sells Epicel directly to hospitals and burn centers based on contracted rates stated in an approved contract or purchase order. Similar to MACI, there is no obligation to manufacture Epicel grafts upon receipt of a skin biopsy, and Vericel has no contractual right to receive payment until the product is delivered to the hospital. The Company recognizes product revenue from sales of Epicel upon delivery to the hospital, at which time the customer is in control of the Epicel grafts and the claim is billable to the hospital. NexoBrid The Company entered into exclusive license and supply agreements with MediWound in May 2019, under which MediWound will manufacture and supply NexoBrid on a unit price basis, which may be increased pursuant to the terms of the agreements. The U.S. Biomedical Advanced Research and Development Authority (“BARDA”) has committed to procure NexoBrid from MediWound and, as of March 31, 2022, the Company did not hold a direct contract or distribution agreement with BARDA, or take title to the product. The Company recognizes revenue based on a percentage of gross profits for sales of NexoBrid to BARDA upon delivery, at which time BARDA is in control of the product. Revenue by Product and Customer The following table and descriptions below show the products from which the Company generated its revenue: Three Months Ended March 31, Revenue by product (in thousands) 2022 2021 MACI implants and kits Implants based on contracted rates sold through a specialty pharmacy (a) $ 15,190 $ 13,206 Implants subject to third party reimbursement sold through a specialty pharmacy (b) 3,369 4,280 Implants sold direct based on contracted rates (c) 5,634 4,466 Implants sold direct subject to third-party reimbursement (d) 861 849 Biopsy kits - direct bill 522 519 Change in estimates related to prior periods (e) 419 477 Total MACI implants and kits 25,995 23,797 Epicel Direct bill (hospital) 9,857 9,830 NexoBrid revenue (f) 222 941 Total revenue $ 36,074 $ 34,568 (a) Represents implants sold through Orsini and AllCare whereby such specialty pharmacies have a direct contract with the underlying insurance provider. The amount of reimbursement is based on contracted rates at the time of sale supported by the pharmacy’s direct contracts. (b) Represents implants sold through Orsini or AllCare whereby such specialty pharmacy does not have a direct contract with the underlying payer. The amount of reimbursement is established based on a payer or state fee schedule and/or payer history. (c) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. Also represents direct sales under a contract to specialty distributor DMS. (d) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. The payment terms are subject to third-party reimbursement from an underlying insurance provider. (e) Primarily represents changes in estimates related to implants sold through Orsini or AllCare in which such specialty pharmacy does not have a direct contract with the underlying payer. The initial estimate of the amount of reimbursement is established based on a payer or state fee schedule and/or payer history. The change in estimates is a result of additional information, changes in collection expectations or actual cash collections received in the current period. (f) Represents revenue based on a percentage of gross profits for sales of NexoBrid to BARDA, pursuant to the license agreement between the Company and MediWound. Concentration of Credit Risk The Company’s total revenue concentration from an Epicel customer for the three months ended March 31, 2022 and 2021 was 8% and 14%, respectively. For the Company’s total accounts receivable balances, there were no customers as of March 31, 2022 or December 31, 2021, with a concentration greater than 10%.

Selected Balance Sheet Componen

Selected Balance Sheet Components	3 Months Ended
	Mar. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Selected Balance Sheet Components	Selected Balance Sheet Components Inventory Inventory as of March 31, 2022 and December 31, 2021: (In thousands) March 31, 2022 December 31, 2021 Raw materials $ 13,264 $ 12,676 Work-in-process 1,057 644 Finished goods 64 61 Total inventory $ 14,385 $ 13,381 Property and Equipment Property and Equipment, net as of March 31, 2022 and December 31, 2021: (In thousands) March 31, 2022 December 31, 2021 Machinery and equipment $ 4,514 $ 4,522 Furniture, fixtures and office equipment 1,551 1,551 Computer equipment and software 7,934 7,769 Leasehold improvements 10,616 10,617 Construction in process 4,966 3,097 Financing right-of-use lease 65 74 Total property and equipment, gross 29,646 27,630 Less accumulated depreciation (15,195) (14,322) Total property and equipment, net $ 14,451 $ 13,308 Depreciation expense for the three months ended March 31, 2022 and 2021 was $0.9 million and $0.8 million, respectively. Accrued Expenses Accrued Expenses as of March 31, 2022 and December 31, 2021 are as follows: (In thousands) March 31, 2022 December 31, 2021 Bonus related compensation $ 2,483 $ 6,305 Employee related accruals 3,112 3,616 Insurance reimbursement-related liabilities 5,111 3,973 Other accrued expenses 87 151 Total accrued expenses $ 10,793 $ 14,045

Leases

Leases	3 Months Ended
	Mar. 31, 2022
Leases [Abstract]
Leases	LeasesThe Company leases facilities in Ann Arbor, Michigan and Cambridge, Massachusetts. The Ann Arbor facility includes office space, and the Cambridge facilities include clean rooms, laboratories for MACI and Epicel manufacturing, and office space. The Company also leases offsite warehouse space, vehicles and computer equipment. On January 28, 2022, the Company entered into a Lease Agreement (the “Burlington Lease”) to lease approximately 126,000 square feet of to-be-constructed manufacturing, laboratory and office space in Burlington, Massachusetts (the “Premises”). Once constructed, the Premises will serve as the Company’s new corporate headquarters and primary manufacturing facility. The term of the Burlington Lease is scheduled to begin 12 months following the landlord’s commencement of construction of the core and shell of the building in which the Premises are located, which is currently expected to be February 28, 2023 (the “Commencement Date”). The Company’s obligation to pay rent for the Premises will begin on the earlier of: 13 months from the Commencement Date; or the date on which the Company first occupies the Premises to conduct operations (the “Rent Commencement Date”). The initial term of the Lease is 144 months following the Rent Commencement Date. The Company has a one-time option to extend the term of the Lease for an additional 10 years, exercisable under certain conditions and at a market rate determined in accordance with the Burlington Lease. The annual base rent of the Burlington Lease is initially $57 per square foot per year, subject to annual increases of 2.5%. Monthly contractual payments are expected to range from $0.6 million to $0.8 million. Additionally, the Company is responsible for reimbursing the landlord for the Company’s share of the Premises’ property taxes and certain other operating expenses. The Burlington Lease also provides for a tenant improvement allowance from the landlord in an amount equal to $200 per square foot of the Premises, or approximately $25.1 million in total, towards the design and construction of certain tenant improvements made to the Premises, subject to the terms set forth in the Burlington Lease. The Company is not involved in the initial construction of the core and shell of the building and will record the lease liability and right-of-use asset on its condensed consolidated balance sheet, when the construction is substantially completed and it obtains control of the Premises, which is currently expected to be on or around the Commencement Date. In January 2022, in connection with the execution of the Burlington Lease, the Company issued a letter of credit collateralized by cash deposits of approximately $6.0 million. Such letter of credit shall be reduced to approximately $4.2 million and $1.8 million at the conclusion of the third and sixth lease years, respectively, provided certain conditions set forth in the Burlington Lease are satisfied. For the three months ended March 31, 2022 and 2021, lease expense of less than $0.1 million was recorded related to short-term leases. For the three months ended March 31, 2022 and 2021, the Company recognized $1.7 million and $1.9 million, respectively, of operating lease expense. For the three months ended March 31, 2022 and 2021, the Company recognized less than $0.1 million of financing lease expense. Operating and finance lease assets and liabilities are as follows: (In thousands) Classification March 31, 2022 December 31, 2021 Assets Operating Right-of-use assets $ 44,653 $ 45,720 Finance Property and equipment, net 65 73 Total leased assets $ 44,718 $ 45,793 Liabilities Current Operating Current portion of operating lease liabilities $ 3,147 $ 2,950 Finance Other current liabilities 41 41 $ 3,188 $ 2,991 Non-current Operating Operating lease liabilities $ 46,053 $ 47,147 Finance Other long-term liabilities 19 44 Total leased liabilities $ 46,072 $ 47,191
Leases	LeasesThe Company leases facilities in Ann Arbor, Michigan and Cambridge, Massachusetts. The Ann Arbor facility includes office space, and the Cambridge facilities include clean rooms, laboratories for MACI and Epicel manufacturing, and office space. The Company also leases offsite warehouse space, vehicles and computer equipment. On January 28, 2022, the Company entered into a Lease Agreement (the “Burlington Lease”) to lease approximately 126,000 square feet of to-be-constructed manufacturing, laboratory and office space in Burlington, Massachusetts (the “Premises”). Once constructed, the Premises will serve as the Company’s new corporate headquarters and primary manufacturing facility. The term of the Burlington Lease is scheduled to begin 12 months following the landlord’s commencement of construction of the core and shell of the building in which the Premises are located, which is currently expected to be February 28, 2023 (the “Commencement Date”). The Company’s obligation to pay rent for the Premises will begin on the earlier of: 13 months from the Commencement Date; or the date on which the Company first occupies the Premises to conduct operations (the “Rent Commencement Date”). The initial term of the Lease is 144 months following the Rent Commencement Date. The Company has a one-time option to extend the term of the Lease for an additional 10 years, exercisable under certain conditions and at a market rate determined in accordance with the Burlington Lease. The annual base rent of the Burlington Lease is initially $57 per square foot per year, subject to annual increases of 2.5%. Monthly contractual payments are expected to range from $0.6 million to $0.8 million. Additionally, the Company is responsible for reimbursing the landlord for the Company’s share of the Premises’ property taxes and certain other operating expenses. The Burlington Lease also provides for a tenant improvement allowance from the landlord in an amount equal to $200 per square foot of the Premises, or approximately $25.1 million in total, towards the design and construction of certain tenant improvements made to the Premises, subject to the terms set forth in the Burlington Lease. The Company is not involved in the initial construction of the core and shell of the building and will record the lease liability and right-of-use asset on its condensed consolidated balance sheet, when the construction is substantially completed and it obtains control of the Premises, which is currently expected to be on or around the Commencement Date. In January 2022, in connection with the execution of the Burlington Lease, the Company issued a letter of credit collateralized by cash deposits of approximately $6.0 million. Such letter of credit shall be reduced to approximately $4.2 million and $1.8 million at the conclusion of the third and sixth lease years, respectively, provided certain conditions set forth in the Burlington Lease are satisfied. For the three months ended March 31, 2022 and 2021, lease expense of less than $0.1 million was recorded related to short-term leases. For the three months ended March 31, 2022 and 2021, the Company recognized $1.7 million and $1.9 million, respectively, of operating lease expense. For the three months ended March 31, 2022 and 2021, the Company recognized less than $0.1 million of financing lease expense. Operating and finance lease assets and liabilities are as follows: (In thousands) Classification March 31, 2022 December 31, 2021 Assets Operating Right-of-use assets $ 44,653 $ 45,720 Finance Property and equipment, net 65 73 Total leased assets $ 44,718 $ 45,793 Liabilities Current Operating Current portion of operating lease liabilities $ 3,147 $ 2,950 Finance Other current liabilities 41 41 $ 3,188 $ 2,991 Non-current Operating Operating lease liabilities $ 46,053 $ 47,147 Finance Other long-term liabilities 19 44 Total leased liabilities $ 46,072 $ 47,191

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2022
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based CompensationThe 2022 Omnibus Incentive Plan (“2022 Plan”) was approved on April 27, 2022, and provides incentives through the grant of stock options, stock appreciation rights, restricted stock awards and restricted stock units. The exercise price of stock options granted under the 2022 Plan shall not be less than the fair market value of the Company’s common stock on the date of grant. The 2022 Plan replaced the 1992 Stock Option Plan, the 2001 Stock Option Plan, the Amended and Restated 2004 Equity Incentive Plan, the 2009 Second Amended and Restated Omnibus Incentive Plan, the 2017 Omnibus Incentive Plan, and the Amended and Restated 2019 Omnibus Incentive Plan (“Prior Plans”), and no new grants have been granted under the Prior Plans after approval. However, the expiration or forfeiture of options previously granted under the Prior Plans will increase the number of shares available for issuance under the 2022 Plan. Stock Compensation Expense Non-cash stock-based compensation expense (service-based stock options, restricted stock units and employee stock purchase plan) is summarized in the following table: Three Months Ended March 31, (in thousands) 2022 2021 Cost of product sales $ 1,118 $ 911 Research and development 1,350 863 Selling, general and administrative 7,063 5,245 Total non-cash stock-based compensation expense $ 9,531 $ 7,019 Service-Based Stock Options During the three months ended March 31, 2022 and 2021, the Company granted service-based options to purchase common stock of 993,589 and 1,337,955, respectively. The weighted-average grant-date fair value of service-based options granted during the three months ended March 31, 2022 and 2021 was $20.99 and $32.02 per option, respectively. Restricted Stock Units

Investments

Investments	3 Months Ended
	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Marketable debt securities held by the Company are classified as available-for-sale pursuant to ASC 320, Investments – Debt and Equity Securities , and carried at fair value in the accompanying condensed consolidated balance sheets on a settlement date basis. The following tables summarize the gross unrealized gains and losses of the Company’s marketable securities as of March 31, 2022 and December 31, 2021: March 31, 2022 Gross Unrealized Estimated Fair Value (In thousands) Amortized Cost Gains Losses Credit Losses Commercial paper $ 15,241 $ — $ (38) $ — $ 15,203 Corporate notes 53,063 — (575) — 52,488 $ 68,304 $ — $ (613) $ — $ 67,691 Classified as: Short-term investments $ 44,888 Long-term investments 22,803 $ 67,691 December 31, 2021 Gross Unrealized Estimated Fair Value (In thousands) Amortized Cost Gains Losses Credit Losses Commercial paper $ 10,243 $ — $ (12) $ — $ 10,231 Corporate notes 50,666 — (142) — 50,524 $ 60,909 $ — $ (154) $ — $ 60,755 Classified as: Short-term investments $ 35,068 Long-term investments 25,687 $ 60,755 As of March 31, 2022 and December 31, 2021 , all marketable securities held by the Company had remaining contractual maturities of three years or less. There have been no impairments of the Company’s assets measured and carried at fair value during the three months ended March 31, 2022 and 2021.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company’s fair value measurements are classified and disclosed in one of the following three categories: • 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 liability; • 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). Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The commercial paper and corporate notes are classified as Level 2 as they were valued based upon quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant inputs are observable in the market or can be corroborated by observable market data for substantially the full term of the assets. There were no transfers into or out of Level 3 from December 31, 2021 to March 31, 2022. The following table summarizes the valuation of the Company’s financial instruments that are measured at fair value on a recurring basis: March 31, 2022 December 31, 2021 Fair value measurement category Fair value measurement category (In thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Assets: Money market funds $ 1,884 $ 1,884 $ — $ — $ 1,258 $ 1,258 $ — $ — Commercial paper (a) 15,203 — 15,203 — 18,229 — 18,229 — Corporate notes 52,488 — 52,488 — 50,524 — 50,524 — $ 69,575 $ 1,884 $ 67,691 $ — $ 70,011 $ 1,258 $ 68,753 $ — (a) Approximately $8.0 million of commercial paper had an original maturity of 90 days or less and was recorded as a cash equivalent as of December 31, 2021.

Net Loss Per Common Share

Net Loss Per Common Share	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Net Loss Per Common Share	Net Loss Per Common ShareA summary of net loss per common share is presented below: Three Months Ended March 31, (Amounts in thousands, except per share amounts) 2022 2021 Net loss $ (7,091) $ (3,289) Basic weighted-average common shares outstanding 46,985 45,984 Effect of dilutive stock options and restricted stock units — — Diluted weighted-average common shares outstanding 46,985 45,984 Basic loss per common share $ (0.15) $ (0.07) Diluted loss per common share $ (0.15) $ (0.07) Anti-dilutive shares excluded from diluted net loss per common share: Stock options 6,479 6,183 Restricted stock units 625 406

NexoBrid License and Supply Agr

NexoBrid License and Supply Agreements	3 Months Ended
	Mar. 31, 2022
Related Party Transactions [Abstract]
NexoBrid License and Supply Agreements	NexoBrid License and Supply Agreements On May 6, 2019, the Company entered into exclusive license and supply agreements with MediWound to commercialize NexoBrid and any improvements to NexoBrid in North America. NexoBrid is a topically-administered biological product that enzymatically removes nonviable burn tissue, or eschar, in patients with deep partial and full-thickness thermal burns. On June 29, 2021, the Company announced that MediWound had received a complete response letter from the U.S. Food & Drug Administration (“FDA”) with respect to a biologics license application (“BLA”), which MediWound had previously submitted to the FDA seeking marketing approval for the product in the U.S. As part of the complete response letter, the FDA communicated to MediWound that it had completed its review of the BLA, as amended, and had determined that it cannot approve the BLA in its present form. The Company continues to work with MediWound, BARDA and the FDA to address the issues identified in the agency’s complete response letter, to prepare and submit a BLA resubmission to the FDA and to seek the potential approval of NexoBrid. Pursuant to the terms of the license agreement, if the BLA is approved, MediWound will transfer the BLA to Vericel and Vericel will market NexoBrid in the U.S. Both MediWound and Vericel, under the supervision of a Central Steering Committee comprised of members of both companies will continue to guide the development of NexoBrid in North America (the “Central Steering Committee”). NexoBrid is approved in the European Union (“EU”) and other international markets and has been designated as an orphan biologic in the U.S., EU and other international markets. In May 2019, the Company paid MediWound $17.5 million in consideration for the license, which was recorded as research and development expense during 2019. The Company is also obligated to pay MediWound $7.5 million, which is contingent upon U.S. regulatory approval of the BLA for NexoBrid and up to $125.0 million contingent upon meeting certain sales milestones. The first sales milestone of $7.5 million would be triggered when annual net sales of NexoBrid or improvements to it in North America exceed $75.0 million. As of March 31, 2022, the milestone payments are not yet probable and therefore, not recorded as a liability. The Company also will pay MediWound tiered royalties on net sales ranging from mid-high single-digit to mid-teen percentages, subject to customary reductions. The Company also entered into a supply agreement with MediWound under which MediWound will manufacture NexoBrid for the Company on a unit price basis which may be increased based on a published index. MediWound is obligated to supply the Company with NexoBrid for sale in North America on an exclusive basis for the first five years of the term of the supply agreement. After the exclusivity period or upon supply failure, the Company will be permitted to establish an alternate source of supply.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies From time to time, the Company could be a party to various legal proceedings arising in the ordinary course of business. The costs and outcome of litigation, regulatory, investigatory or other proceedings cannot be predicted with certainty, and some lawsuits, claims, actions or proceedings may be disposed of unfavorably to the Company and could have a material adverse effect on the Company’s results of operations or financial condition. In addition, intellectual property disputes often have a risk of injunctive relief which, if imposed against the Company, could materially and adversely affect its financial condition or results of operations. If a matter is both probable to result in material liability and the amount of loss can be reasonably estimated, the Company estimates and discloses the possible material loss or range of loss. If such loss is not probable or cannot be reasonably estimated, a liability is not recorded in its condensed consolidated financial statements. As of March 31, 2022, the Company has no material ongoing litigation in which the Company was a party or any material ongoing regulatory or other proceedings and had no knowledge of any investigations by government or regulatory authorities in which the Company is a target that could have a material adverse effect on its current business.

Basis of Presentation (Policies

Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements No new Accounting Standards were adopted during the quarter ended March 31, 2022.

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 31, 2022
Risks and Uncertainties [Abstract]
Disaggregation of Revenue	The following table and descriptions below show the products from which the Company generated its revenue: Three Months Ended March 31, Revenue by product (in thousands) 2022 2021 MACI implants and kits Implants based on contracted rates sold through a specialty pharmacy (a) $ 15,190 $ 13,206 Implants subject to third party reimbursement sold through a specialty pharmacy (b) 3,369 4,280 Implants sold direct based on contracted rates (c) 5,634 4,466 Implants sold direct subject to third-party reimbursement (d) 861 849 Biopsy kits - direct bill 522 519 Change in estimates related to prior periods (e) 419 477 Total MACI implants and kits 25,995 23,797 Epicel Direct bill (hospital) 9,857 9,830 NexoBrid revenue (f) 222 941 Total revenue $ 36,074 $ 34,568 (a) Represents implants sold through Orsini and AllCare whereby such specialty pharmacies have a direct contract with the underlying insurance provider. The amount of reimbursement is based on contracted rates at the time of sale supported by the pharmacy’s direct contracts. (b) Represents implants sold through Orsini or AllCare whereby such specialty pharmacy does not have a direct contract with the underlying payer. The amount of reimbursement is established based on a payer or state fee schedule and/or payer history. (c) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. Also represents direct sales under a contract to specialty distributor DMS. (d) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. The payment terms are subject to third-party reimbursement from an underlying insurance provider. (e) Primarily represents changes in estimates related to implants sold through Orsini or AllCare in which such specialty pharmacy does not have a direct contract with the underlying payer. The initial estimate of the amount of reimbursement is established based on a payer or state fee schedule and/or payer history. The change in estimates is a result of additional information, changes in collection expectations or actual cash collections received in the current period. (f) Represents revenue based on a percentage of gross profits for sales of NexoBrid to BARDA, pursuant to the license agreement between the Company and MediWound.

Selected Balance Sheet Compon_2

Selected Balance Sheet Components (Tables)	3 Months Ended
	Mar. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Schedule of inventory	Inventory as of March 31, 2022 and December 31, 2021: (In thousands) March 31, 2022 December 31, 2021 Raw materials $ 13,264 $ 12,676 Work-in-process 1,057 644 Finished goods 64 61 Total inventory $ 14,385 $ 13,381
Schedule of property and equipment, net	Property and Equipment, net as of March 31, 2022 and December 31, 2021: (In thousands) March 31, 2022 December 31, 2021 Machinery and equipment $ 4,514 $ 4,522 Furniture, fixtures and office equipment 1,551 1,551 Computer equipment and software 7,934 7,769 Leasehold improvements 10,616 10,617 Construction in process 4,966 3,097 Financing right-of-use lease 65 74 Total property and equipment, gross 29,646 27,630 Less accumulated depreciation (15,195) (14,322) Total property and equipment, net $ 14,451 $ 13,308
Schedule of accrued expenses	Accrued Expenses as of March 31, 2022 and December 31, 2021 are as follows: (In thousands) March 31, 2022 December 31, 2021 Bonus related compensation $ 2,483 $ 6,305 Employee related accruals 3,112 3,616 Insurance reimbursement-related liabilities 5,111 3,973 Other accrued expenses 87 151 Total accrued expenses $ 10,793 $ 14,045

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2022
Leases [Abstract]
Assets and Liabilities	Operating and finance lease assets and liabilities are as follows: (In thousands) Classification March 31, 2022 December 31, 2021 Assets Operating Right-of-use assets $ 44,653 $ 45,720 Finance Property and equipment, net 65 73 Total leased assets $ 44,718 $ 45,793 Liabilities Current Operating Current portion of operating lease liabilities $ 3,147 $ 2,950 Finance Other current liabilities 41 41 $ 3,188 $ 2,991 Non-current Operating Operating lease liabilities $ 46,053 $ 47,147 Finance Other long-term liabilities 19 44 Total leased liabilities $ 46,072 $ 47,191

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2022
Share-based Payment Arrangement [Abstract]
Schedule of Non-cash Stock-based Compensation Expense	Non-cash stock-based compensation expense (service-based stock options, restricted stock units and employee stock purchase plan) is summarized in the following table: Three Months Ended March 31, (in thousands) 2022 2021 Cost of product sales $ 1,118 $ 911 Research and development 1,350 863 Selling, general and administrative 7,063 5,245 Total non-cash stock-based compensation expense $ 9,531 $ 7,019

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Schedule of fair value of securities, not including cash	The following tables summarize the gross unrealized gains and losses of the Company’s marketable securities as of March 31, 2022 and December 31, 2021: March 31, 2022 Gross Unrealized Estimated Fair Value (In thousands) Amortized Cost Gains Losses Credit Losses Commercial paper $ 15,241 $ — $ (38) $ — $ 15,203 Corporate notes 53,063 — (575) — 52,488 $ 68,304 $ — $ (613) $ — $ 67,691 Classified as: Short-term investments $ 44,888 Long-term investments 22,803 $ 67,691 December 31, 2021 Gross Unrealized Estimated Fair Value (In thousands) Amortized Cost Gains Losses Credit Losses Commercial paper $ 10,243 $ — $ (12) $ — $ 10,231 Corporate notes 50,666 — (142) — 50,524 $ 60,909 $ — $ (154) $ — $ 60,755 Classified as: Short-term investments $ 35,068 Long-term investments 25,687 $ 60,755

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Summary of valuation of the Company's investments and financial instruments that are measured at fair value on a recurring basis	The following table summarizes the valuation of the Company’s financial instruments that are measured at fair value on a recurring basis: March 31, 2022 December 31, 2021 Fair value measurement category Fair value measurement category (In thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Assets: Money market funds $ 1,884 $ 1,884 $ — $ — $ 1,258 $ 1,258 $ — $ — Commercial paper (a) 15,203 — 15,203 — 18,229 — 18,229 — Corporate notes 52,488 — 52,488 — 50,524 — 50,524 — $ 69,575 $ 1,884 $ 67,691 $ — $ 70,011 $ 1,258 $ 68,753 $ — (a) Approximately $8.0 million of commercial paper had an original maturity of 90 days or less and was recorded as a cash equivalent as of December 31, 2021.

Net Loss Per Common Share (Tabl

Net Loss Per Common Share (Tables)	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Schedule of net loss attributable to common shareholders and share data used in the basic and diluted earnings per share computations using the two class method	A summary of net loss per common share is presented below: Three Months Ended March 31, (Amounts in thousands, except per share amounts) 2022 2021 Net loss $ (7,091) $ (3,289) Basic weighted-average common shares outstanding 46,985 45,984 Effect of dilutive stock options and restricted stock units — — Diluted weighted-average common shares outstanding 46,985 45,984 Basic loss per common share $ (0.15) $ (0.07) Diluted loss per common share $ (0.15) $ (0.07) Anti-dilutive shares excluded from diluted net loss per common share: Stock options 6,479 6,183 Restricted stock units 625 406

Organization (Details)

Organization (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)productsegment	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of therapy products | product	2
Number of reportable segments | segment	1
Accumulated deficit	$ 390,377		$ 383,286
Net loss	7,091	$ 3,289
Cash and cash equivalents	55,659	$ 58,154	$ 68,330
Short term investments	$ 67,700

Revenue - Narrative (Details)

Revenue - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022USD ($)pharmacy	Dec. 31, 2021USD ($)
Risks and Uncertainties [Abstract]
Number of specialty pharmacies | pharmacy	2
Allowance for doubtful accounts	$ 6.7	$ 7
Change in estimate of uncollectible (percent)	0.50%
Change in revenue recognized due to 0.5% change in uncollectible percentage	$ 0.3

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Product sales, net	$ 35,852	$ 33,627
Other revenue	222	941
Total revenue	36,074	34,568
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606
Disaggregation of Revenue [Line Items]
Product sales, net	419	477
MACI implants Aad kits
Disaggregation of Revenue [Line Items]
Product sales, net	25,995	23,797
Through Intermediary | Implants | Contract rate
Disaggregation of Revenue [Line Items]
Product sales, net	15,190	13,206
Through Intermediary | Implants | Time-and-materials contract
Disaggregation of Revenue [Line Items]
Product sales, net	3,369	4,280
Time-and-materials contract | Implants | Time-and-materials contract
Disaggregation of Revenue [Line Items]
Product sales, net	861	849
Provider or Facility | Implants | Contract rate
Disaggregation of Revenue [Line Items]
Product sales, net	5,634	4,466
Provider or Facility | NexoBid revenue
Disaggregation of Revenue [Line Items]
Other revenue	222	941
Directly to consumer | Biopsy kits
Disaggregation of Revenue [Line Items]
Product sales, net	522	519
Directly to consumer | Epicel
Disaggregation of Revenue [Line Items]
Product sales, net	$ 9,857	$ 9,830

Revenue - Schedules of concentr

Revenue - Schedules of concentration of risk (Details)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Revenue Concentration | Customer concentration | Epicel
Product Information [Line Items]
Concentration risk (as a percent)	8.00%	14.00%

Selected Balance Sheet Compon_3

Selected Balance Sheet Components - Schedule of inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Inventory:
Raw materials	$ 13,264	$ 12,676
Work-in-process	1,057	644
Finished goods	64	61
Total inventory	$ 14,385	$ 13,381

Selected Balance Sheet Compon_4

Selected Balance Sheet Components - Schedule of property and equipment, net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property and equipment, net:
Financing right-of-use lease	$ 65	$ 74
Total property and equipment, gross	29,646	27,630
Less accumulated depreciation	(15,195)	(14,322)
Total property and equipment, net	14,451	13,308
Machinery and equipment
Property and equipment, net:
Total property and equipment, gross	4,514	4,522
Furniture, fixtures and office equipment
Property and equipment, net:
Total property and equipment, gross	1,551	1,551
Computer equipment and software
Property and equipment, net:
Total property and equipment, gross	7,934	7,769
Leasehold improvements
Property and equipment, net:
Total property and equipment, gross	10,616	10,617
Construction in process
Property and equipment, net:
Total property and equipment, gross	$ 4,966	$ 3,097

Selected Balance Sheet Compon_5

Selected Balance Sheet Components - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Balance Sheet Related Disclosures [Abstract]
Depreciation and amortization expense	$ 873	$ 811

Selected Balance Sheet Compon_6

Selected Balance Sheet Components - Schedule of accrued expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accrued expenses
Bonus related compensation	$ 2,483	$ 6,305
Employee related accruals	3,112	3,616
Insurance reimbursement-related liabilities	5,111	3,973
Other accrued expenses	87	151
Total accrued expenses	$ 10,793	$ 14,045

Leases - Narrative (Details)

Leases - Narrative (Details) ft² in Thousands, $ in Millions	Jan. 28, 2022USD ($)ft²uSDollarPerSquareFoot	Jan. 31, 2022USD ($)	Mar. 31, 2022USD ($)	Mar. 31, 2021USD ($)
Lessee, Lease, Description [Line Items]
Short-term lease costs (less than)			$ 0.1	$ 0.1
Operating lease expense			1.7	1.9
Finance lease expense (less than)			$ 0.1	$ 0.1
25 Network Drive, Burlington, Massachusetts
Lessee, Lease, Description [Line Items]
Area of real estate property | ft²	126
Lease comment, grace period	12 months
Rent start date, term	13 months
Term of contract	144 months
Lease option to extend term	10 years
Annual lease per square foot | uSDollarPerSquareFoot	57
Annual lease increase limit, percentage	2.50%
Tenant improvement allowance per square foot | uSDollarPerSquareFoot	200
Tenant improvement allowance	$ 25.1
Letter of credit cash deposit		$ 6
Letter of credit cash deposit lease year three		4.2
Letter of credit cash deposit lease year four		$ 1.8
Minimum | 25 Network Drive, Burlington, Massachusetts
Lessee, Lease, Description [Line Items]
Contractual lease payments	0.6
Maximum | 25 Network Drive, Burlington, Massachusetts
Lessee, Lease, Description [Line Items]
Contractual lease payments	$ 0.8

Leases - Assets And Liabilities

Leases - Assets And Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets
Operating	$ 44,653	$ 45,720
Finance	65	73
Total leased assets	44,718	45,793
Current
Operating	3,147	2,950
Finance	41	41
Lease liability current	3,188	2,991
Non-current
Operating	46,053	47,147
Finance	19	44
Total leased liabilities	$ 46,072	$ 47,191
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property and equipment, net
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other current liabilities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other long-term liabilities

Stock-Based Compensation - Expe

Stock-Based Compensation - Expense (Details) - Employee stock purchase plan and service-based stock options - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	$ 9,531	$ 7,019
Cost of product sales
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	1,118	911
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	1,350	863
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	$ 7,063	$ 5,245

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - $ / shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Stock options
Stock-Based Compensation
Granted (in shares)	993,589	1,337,955
Weighted average grant-date fair value (in dollars per share)	$ 20.99	$ 32.02
Restricted stock units
Stock-Based Compensation
Restricted stock units granted (shares)	343,022	214,113
Weighted-average grant date fair value (in dollars per share)	$ 34.97	$ 50.81

Investments (Details)

Investments (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Marketable Securities [Line Items]
Amortized Cost	$ 68,304,000		$ 60,909,000
Gains	0		0
Losses	(613,000)		(154,000)
Credit Losses	0		0
Estimated Fair Value	$ 67,691,000		$ 60,755,000
Remaining contractual maturity period	3 years		3 years
Impairments of assets	$ 0	$ 0
Short-term investments
Marketable Securities [Line Items]
Estimated Fair Value	44,888,000		$ 35,068,000
Long-term investments
Marketable Securities [Line Items]
Estimated Fair Value	22,803,000		25,687,000
Commercial paper
Marketable Securities [Line Items]
Amortized Cost	15,241,000		10,243,000
Gains	0		0
Losses	(38,000)		(12,000)
Credit Losses	0		0
Estimated Fair Value	15,203,000		10,231,000
Corporate notes
Marketable Securities [Line Items]
Amortized Cost	53,063,000		50,666,000
Gains	0		0
Losses	(575,000)		(142,000)
Credit Losses	0		0
Estimated Fair Value	$ 52,488,000		$ 50,524,000

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	$ 67,691	$ 60,755
Recurring
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	69,575	70,011
Recurring | Level 1
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	1,884	1,258
Recurring | Level 2
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	67,691	68,753
Recurring | Level 3
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	0	0
Recurring | Commercial paper
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	15,203	18,229
Recurring | Commercial paper | Cash and Cash Equivalents
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value		8,000
Recurring | Commercial paper | Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring | Commercial paper | Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	15,203	18,229
Recurring | Commercial paper | Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring | Corporate notes
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	52,488	50,524
Recurring | Corporate notes | Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring | Corporate notes | Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	52,488	50,524
Recurring | Corporate notes | Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring | Money market funds
Liabilities that are measured at fair value on a recurring basis
Money market funds	1,884	1,258
Recurring | Money market funds | Level 1
Liabilities that are measured at fair value on a recurring basis
Money market funds	1,884	1,258
Recurring | Money market funds | Level 2
Liabilities that are measured at fair value on a recurring basis
Money market funds	0	0
Recurring | Money market funds | Level 3
Liabilities that are measured at fair value on a recurring basis
Money market funds	$ 0	$ 0

Net Loss Per Common Share (Deta

Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Net Income (Loss) Attributable to Parent [Abstract]
Net loss	$ (7,091)	$ (3,289)
Basic weighted-average common shares outstanding (in shares)	46,985	45,984
Diluted weighted-average common shares outstanding (in shares)	46,985	45,984
Basic loss per common share (in USD per share)	$ (0.15)	$ (0.07)
Diluted loss per common share (in USD per share)	$ (0.15)	$ (0.07)
Stock options
Anti-dilutive shares excluded from diluted net loss per common share:
Aggregate number of common equivalent shares (related to options, warrants and preferred stock) that have been excluded from computations of diluted net loss per common share (in shares)	6,479	6,183
Restricted stock units
Net Income (Loss) Attributable to Parent [Abstract]
Effect of dilutive stock options and restricted stock units	0	0
Anti-dilutive shares excluded from diluted net loss per common share:
Aggregate number of common equivalent shares (related to options, warrants and preferred stock) that have been excluded from computations of diluted net loss per common share (in shares)	625	406

NexoBrid License and Supply A_2

NexoBrid License and Supply Agreements (Details) - MediWound Ltd $ in Millions	1 Months Ended
	May 31, 2019USD ($)
Related Party Transaction [Line Items]
Consideration payment for license	$ 17.5
Contingent consideration	7.5
Max contingent consideration	125
Sales Initial milestone	$ 75
Term of supply agreement	5 years