0001628280-21-008983 | 10-Q | XBRL Viewer

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Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
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		46,355,625
Entity Central Index Key	0000887359
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 58,154	$ 33,620
Short-term investments	25,402	42,187
Accounts receivable (net of allowance for doubtful accounts of $121 and $143, respectively)	29,122	34,504
Inventory	10,322	9,356
Other current assets	4,213	3,893
Total current assets	127,213	123,560
Property and equipment, net	9,076	7,633
Restricted cash	211	211
Right-of-use assets	48,943	50,105
Long-term investments	26,021	24,099
Total assets	211,464	205,608
Current liabilities:
Accounts payable	8,826	6,755
Accrued expenses	9,965	11,293
Current portion of operating lease liabilities	4,398	4,394
Other liabilities	41	41
Total current liabilities	23,230	22,483
Operating lease liabilities	47,968	48,789
Other long-term liabilities	57	76
Total liabilities	71,255	71,348
COMMITMENTS AND CONTINGENCIES
Shareholders’ equity:
Common stock, no par value; shares authorized — 75,000; shares issued and outstanding — 46,225 and 45,804, respectively	519,360	510,061
Accumulated other comprehensive income (loss)	(47)	14
Accumulated deficit	(379,104)	(375,815)
Total shareholders’ equity	140,209	134,260
Total liabilities and shareholders’ equity	$ 211,464	$ 205,608

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 121	$ 143
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	46,225,000	45,804,000
Common stock, shares outstanding (in shares)	46,225,000	45,804,000

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Product sales, net	$ 33,627	$ 26,678
Other revenue	941	0
Total revenue	34,568	26,678
Cost of product sales	11,583	9,922
Gross profit	22,985	16,756
Research and development	3,630	3,763
Selling, general and administrative	22,660	18,069
Total operating expenses	26,290	21,832
Loss from operations	(3,305)	(5,076)
Other income (expense):
Interest income	76	306
Other income	(1)	(2)
Interest expense	84	67
Total other income	159	371
Net loss before tax provision	(3,146)	(4,705)
Tax provision	(143)	0
Net loss	$ (3,289)	$ (4,705)
Net loss per share (basic) (in USD per share)	$ (0.07)	$ (0.10)
Net loss per share (diluted) (in USD per share)	$ (0.07)	$ (0.10)
Weighted average number of common shares outstanding (basic) (in shares)	45,984	44,924
Weighted average number of common shares outstanding (diluted) (in shares)	45,984	44,924
Revenue, Product and Service [Extensible List]	us-gaap:ProductMember
Cost, Product and Service [Extensible List]	us-gaap:ProductMember

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (3,289)	$ (4,705)
Other comprehensive loss:
Unrealized gain (loss) on investments	(61)	41
Comprehensive loss	$ (3,350)	$ (4,664)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Accumulated Other Comprehensive Income (loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2019		44,864
Beginning balance at Dec. 31, 2019	$ 111,091	$ 489,749	$ 21	$ (378,679)
Increase (Decrease) in Shareholders' Equity
Net loss	(4,705)			(4,705)
Compensation expense related to stock options and restricted stock units granted, net of forfeitures	3,768	$ 3,768
Stock option exercises (in shares)		57
Stock option exercises	196	$ 196
Shares issued under the Employee Stock Purchase Plan (in shares)		20
Shares issued under the Employee Stock Purchase Plan	224	$ 224
Issuance of stock upon restricted stock unit vesting (in shares)		36
Issuance of stock upon restricted stock unit vesting	0
Restricted stock withheld for employee tax remittance (in shares)		(14)
Restricted stock withheld for employee tax remittance	(163)	$ (163)
Unrealized gain (loss) on investments	41		41
Ending balance (in shares) at Mar. 31, 2020		44,963
Ending balance at Mar. 31, 2020	110,452	$ 493,774	62	(383,384)
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)
Compensation expense related to stock options and restricted stock units granted, net of forfeitures	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 upon restricted stock unit vesting (in shares)		76
Issuance of stock upon 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 gain (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)

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities:
Net loss	$ (3,289)	$ (4,705)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization expense	811	533
Stock compensation expense	7,019	3,768
Foreign currency translation loss	2	7
Gain on sale of fixed assets	(22)	0
Amortization of premiums and discounts on marketable securities	273	(20)
Non-cash lease cost	1,171	794
Changes in operating assets and liabilities:
Inventory	(966)	(466)
Accounts receivable	5,382	7,997
Other current assets	(320)	(549)
Accounts payable	2,174	(59)
Accrued expenses	(1,328)	(1,864)
Operating lease liabilities	(821)	(750)
Net cash provided by operating activities	10,086	4,686
Investing activities:
Purchases of investments	(10,426)	(5,676)
Sales and maturities of investments	24,955	20,135
Expenditures for property, plant and equipment	(2,343)	(717)
Net cash provided by investing activities	12,186	13,742
Financing activities:
Net proceeds from common stock issuance due to stock option exercises	3,781	420
Payments on employee's behalf for taxes related to vesting of restricted stock units	(1,501)	(97)
Other	(18)	(17)
Net cash provided by financing activities	2,262	306
Net increase in cash, cash equivalents, and restricted cash	24,534	18,734
Cash, cash equivalents, and restricted cash at beginning of period	33,831	26,978
Cash, cash equivalents, and restricted cash at end of period	$ 58,365	$ 45,712

Organization	3 Months Ended
Organization	Mar. 31, 2021
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 United States, 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® (concentrate of proteolytic enzymes enriched in bromelain), a registration-stage biological orphan product 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 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 is continually evolving and many state, local and national governments – including those in Massachusetts and Michigan, where the Company's operations are located – have responded at times 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, 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 were, at times, adversely impacted by the effects of COVID-19 during 2020. At the urging of the American College of Surgeons and the United States Surgeon General, hospitals, health systems and surgeons minimized, postponed, or canceled electively scheduled surgeries during the initial wave of the pandemic in the spring of 2020. These recommendations were followed by numerous state level executive orders either restricting or partially restricting elective surgeries. Because MACI is an elective surgical procedure, as a result of these restrictions the Company 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. Although hospitals are now better prepared for a subsequent surge in COVID-19 patients and COVID-19 vaccines have been approved and are being widely distributed in the United States, 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 United States were to rise again, or if new COVID-19 variants emerge which render current vaccine treatments ineffective. Because Epicel is used almost exclusively in the emergent setting by burn centers and surgeons throughout the country, Epicel revenue and procedure volumes have been less affected by the pandemic. At the outset of the pandemic, the Company put in place a comprehensive workplace protection plan, which institutes protective measures in response to COVID-19. These measures include mandatory employee training on social distancing and hygiene protocols, conducting daily health screenings of all employees, vendors and visitors entering our facilities, canceling all international business travel, limiting domestic business travel to essential purposes, requesting that employees limit non-essential personal travel, enhancing our facilities’ janitorial and sanitary procedures, making certain physical modifications and enhancements to our facilities to enable effective social distancing among employees, providing certain personal protective equipment to employees working in our offices, encouraging employees to work from home to the extent their job function enables them to do so, limiting third-party access to the Company’s facilities, encouraging the use of virtual employee meetings, modifying the manner and schedule of on-site production activities, and providing guidance to our field-based commercial teams concerning their communications and contact with customers and healthcare professionals. The Company is reviewing these measures regularly as the pandemic evolves and may take additional actions to the extent required. Depending on the pandemic’s trajectory in the coming months, it may take additional actions to the extent required, or it may ease certain protective measures to the extent available data and state and local rules permit. Going Concern 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, 2021, the Company had an accumulated deficit of $379.1 million, and had a net loss of $3.3 million during the three months ended March 31, 2021. The Company had cash and cash equivalents of $58.2 million and investments of $51.4 million as of March 31, 2021. The Company expects that cash from the sales of our 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. To the extent the United States experiences a resurgence in COVID-19 infections and elective surgery restrictions are reinstated on a widespread basis and significantly impact the Company’s business, the Company 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

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Basis of Presentation

The accompanying Condensed Consolidated Financial Statements as of March 31, 2021 and for the three months ended March 31, 2021 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 our 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 COVID-19 and the actions taken to continue to contain or treat COVID-19, as well as the economic impact on our customers. The Company has made estimates of the impact of COVID-19 within our financial statements and there may be changes to those estimates in future periods. Actual results may differ from these estimates. As of March 31, 2021, the Company has not recorded impairments to investments, inventory, other current assets or long-lived assets as a result of the COVID-19 pandemic and does not expect material impairments in the future.

These Condensed 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, 2020, as filed with the SEC on February 24, 2021 (Annual Report).

Consolidated Statement of Cash Flows

The following table presents certain supplementary cash flows information for the three months ended March 31, 2021 and 2020:


	Three Months Ended March 31,
(In thousands)	2021		2020
Supplementary Cash Flows information:
Non-cash information:

Right-of-use asset and lease liability recognized	$	—	$	326
Additions to property and equipment included in accounts payable	530		105
Restricted shares held for employee tax remittance included in accounts payable	65		66

Cash information:
Interest paid (net of interest capitalized)	$	1	$	2


	Three Months Ended March 31,
(In thousands)	2021		2020
Reconciliation of cash, cash equivalents, and restricted cash reported in the statement of financial position:
Cash and cash equivalents	$	58,154	$	45,623
Restricted cash, included in other long-term assets	211		89
Total cash, cash equivalents, and restricted cash shown in the statement of cash flows	$	58,365	$	45,712

Recent Accounting Pronouncements	3 Months Ended
Recent Accounting Pronouncements	Mar. 31, 2021
Accounting Standards Update and Change in Accounting Principle [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Simplifying the Accounting for Income Taxes In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (ASC 740). The ASU enhances and simplifies various aspects of the income tax accounting guidance in ASC 740, including requirements related to hybrid tax regimes, the tax basis step-up in goodwill obtained in a transaction that is not a business combination, separate financial statements of entities not subject to tax, the intra-period tax allocation exception to the incremental approach, ownership changes in investments, changes from a subsidiary to an equity method investment, interim-period accounting for enacted changes in tax law, and the year-to-date loss limitation in interim-period tax accounting. This guidance became effective for the Company on January 1, 2021 and had no material impact on its Condensed Consolidated Financial Statements.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

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+ Details

Revenue

3 Months Ended

Mar. 31, 2021

Risks and Uncertainties [Abstract]

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. 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 (DMS) for military patients. 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 based on a percentage of published rates. 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. The total allowance for uncollectible consideration as of March 31, 2021 and December 31, 2020 was $6.1 million and $5.3 million, respectively. Changes to the estimate of the amount of consideration that will not be collected could have a material impact to the revenue recognized. A 0.5% change to the estimated uncollectible percentage could result in approximately a $0.2 million increase or decrease in the revenue recognized for the three months ended March 31, 2021.

Changes in estimates of the transaction price are recorded through revenue in the period in which such change occurs. During the three months ended March 31, 2021 and March 31, 2020, changes in estimates related to prior period sales resulted in an increase to revenue of $0.5 million and $1.2 million, respectively. The changes in estimates recorded during the three months ended March 31, 2021 and March 31, 2020, were primarily due to completion of the billing claims process for implants that occurred in 2020 or prior. Upon completion of the billing claims process, the Company concluded that it was probable that a significant reversal in the amount of revenue recognized would not occur.

Additionally, potential credit risk exposure has been evaluated for the Company’s accounts receivable in accordance with ASC 326, Financial Instruments - Credit Losses. The loss percentage is calculated by pooling account receivables containing similar risk characteristics and applying collectability forecasts which are derived from current and historical economic and financial information. The loss percentage calculated was applied to accounts receivables as of March 31, 2021 and December 31, 2020. The allowance related to the potential impacts of COVID-19 on accounts receivable from third-party insurers, government payers, hospitals and patients as of December 31, 2020 included less than $0.1 million, and no additional allowance was recorded during the three months ended March 31, 2021.

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, under which MediWound will manufacture and supply NexoBrid on a unit price basis, which may be increased pursuant to the terms of the agreement. The U.S. Biomedical Advanced Research and Development Authority (BARDA) committed to procure NexoBrid directly from MediWound, under an emergency use authorization. As a result, during 2020, BARDA accepted the first shipments of NexoBrid, per the agreement between BARDA and MediWound. 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. As of March 31, 2021, the Company did not take title to the product or hold a direct contract or distribution agreement with BARDA. During the three months ended March 31, 2021, the Company recognized $0.9 million of revenue. No revenue related to the procurement by BARDA was recognized for the three months ended March 31, 2020. See note 11 for further information.

Revenue by Product and Customer

The following table and description below shows the products from which the Company generated its revenue:


	Three Months Ended March 31,
Revenue by product (in thousands)	2021		2020
MACI implants and kits
Implants based on contracted rate sold through a specialty pharmacy (a)	$	13,206	$	11,338
Implants subject to third party reimbursement sold through a specialty pharmacy (b)	4,280		3,730
Implants sold direct based on contracted rates (c)	4,466		3,109
Implants sold direct subject to third party reimbursement (d)	849		436
Biopsy kits - direct bill	519		466
Change in estimates related to prior periods (e)	477		1,207
Epicel
Direct bill (hospital)	9,830		6,392

Total product revenue	$	33,627	$	26,678
NexoBrid revenue (f)	941		—
Total net revenue	$	34,568	$	26,678

(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 the 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 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 Epicel revenue concentration from a customer for the three months ended March 31, 2021 was 14% and 12% for the same period in 2020. For the Company's total MACI revenue, and MACI and Epicel accounts receivable balances there were no customers for the three months ended March 31, 2021 or March 31, 2020, with a concentration greater than 10%.

Selected Balance Sheet Components

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

Selected Balance Sheet Components

Inventory

Inventory as of March 31, 2021 and December 31, 2020:


(In thousands)	March 31, 2021		December 31, 2020
Raw materials	$	9,409	$	8,775
Work-in-process	884		537
Finished goods	29		44
Inventory	$	10,322	$	9,356

Property and Equipment

Property and Equipment, net as of March 31, 2021 and December 31, 2020:


(In thousands)	March 31, 2021		December 31, 2020
Machinery and equipment	$	3,701	$	3,672
Furniture, fixtures and office equipment	810		809
Computer equipment and software	6,967		6,846
Leasehold improvements	5,594		5,560
Construction in process	4,071		2,021
Financing right-of-use lease	102		111
Total property and equipment, gross	21,245		19,019
Less accumulated depreciation	(12,169)		(11,386)
Property and equipment, net	$	9,076	$	7,633

Depreciation expense for the three months ended March 31, 2021 was $0.8 million and $0.5 million for the same period in 2020.

Accrued Expenses

Accrued Expenses as of March 31, 2021 and December 31, 2020 are as follows:


(In thousands)	March 31, 2021		December 31, 2020
Bonus related compensation	$	2,605	$	5,721
Employee related accruals	4,300		3,482
Other accrued expenses	3,060		2,090
Accrued expenses	$	9,965	$	11,293

Leases

3 Months Ended

Mar. 31, 2021

Leases [Abstract]

Leases

The 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. Certain of the Company’s lease agreements include lease payments that are adjusted periodically for an index or rate. The leases are initially measured using the present value of the projected payments adjusted for the index or rate in effect at the commencement date. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. All operating lease commitments with a lease term greater than 12 months are recognized as right-of-use assets and liabilities, on a discounted basis on the balance sheet. Effective October 21, 2020 the Company entered into an agreement with one of its Cambridge, Massachusetts facility leases. The agreement extended the terms of the lease to expire on February 29, 2032, with monthly contractual lease payments ranging from $0.4 million to $0.6 million. The agreement also provides a tenant improvement allowance of approximately $4.3 million, available through December 31, 2023.

Leases with an initial term of 12 months or less are not recorded on the balance sheet. During the three months ended March 31, 2021 and 2020, lease expense of less than $0.1 million was recorded related to short-term leases. During the three months ended March 31, 2021, the Company recorded $0.2 million of leasehold improvements funded by tenant improvement allowances available under the lease agreements. The contribution toward the cost of tenant improvements is recorded as a reduction of the operating lease assets. For the three months ended March 31, 2021, the Company recognized $1.9 million of operating lease expense and $1.4 million for the same period in 2020. During the three months ended March 31, 2021 and 2020, the Company recognized less than $0.1 million of financing lease expense. The Company’s leases contain non-lease components and activities that do not transfer a good or service to the Company. The Company elected not to combine lease and non-lease components and therefore non-lease costs were not included in the net lease assets or lease liabilities.

Total leased assets and liabilities classified on the balance sheet, as of March 31, 2021 and December 31, 2020 are as follows:


(In thousands)	Classification	March 31, 2021		December 31, 2020
Assets
Operating	Right-of-use assets	$	48,943	$	50,105
Finance	Property and equipment, net	102		111
		$	49,045	$	50,216
Liabilities
Current
Operating	Current portion of operating lease liabilities	$	4,398	$	4,394
Finance	Other liabilities	41		41
		$	4,439	$	4,435
Non-current
Operating	Operating lease liabilities	$	47,968	$	48,789
Finance	Other long-term liabilities	57		76
		$	48,025	$	48,865

Leases

Total leased assets and liabilities classified on the balance sheet, as of March 31, 2021 and December 31, 2020 are as follows:


(In thousands)	Classification	March 31, 2021		December 31, 2020
Assets
Operating	Right-of-use assets	$	48,943	$	50,105
Finance	Property and equipment, net	102		111
		$	49,045	$	50,216
Liabilities
Current
Operating	Current portion of operating lease liabilities	$	4,398	$	4,394
Finance	Other liabilities	41		41
		$	4,439	$	4,435
Non-current
Operating	Operating lease liabilities	$	47,968	$	48,789
Finance	Other long-term liabilities	57		76
		$	48,025	$	48,865

Stock-Based Compensation

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation

Stock Option, Restricted Stock Units and Equity Incentive Plans

The Company has historically had various stock incentive plans and agreements that provide for the issuance of nonqualified and incentive stock options and restricted stock units as well as other equity awards. Such awards may be granted by the Company’s Board of Directors to certain of the Company’s employees, directors and consultants.

Options granted to employees and non-employees under these plans expire no later than ten years from the date of grant. Options and restricted stock units generally become exercisable or vest over a four year period, under a graded-vesting methodology for stock options and annually on the anniversary grant date for restricted stock units, following the date of grant. The Company generally issues new shares upon the exercise of stock options or vesting of restricted stock units.

The Amended and Restated 2019 Omnibus Incentive Plan (2019 Plan) was approved on April 29, 2020 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 2019 Plan shall not be less than the fair market value of the Company’s common stock on the date of grant. The 2019 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 and the 2017 Omnibus Incentive Plan (Prior Plans), and no new grants have been granted under the Prior Plans after approval of the 2019 Plan. However, the expiration or forfeiture of options previously granted under the Prior Plans will increase the number of shares available for issuance under the 2019 Plan.

As of March 31, 2021, there were 2,942,648 shares available for future grant under the 2019 Plan.

Employee Stock Purchase Plan

Employees are able to purchase stock under the Vericel Corporation Employee Stock Purchase Plan (ESPP). The ESPP allows for the issuance of an aggregate of 1,000,000 shares of common stock of which 720,228 shares have been issued since the inception of the plan in 2015. Participation in this plan is available to substantially all employees. The ESPP is a compensatory plan accounted for under the expense recognition provisions of the share-based payment accounting standards. Compensation expense is recorded based on the fair market value of the options at the grant date, which corresponds to the first day of each purchase period and is amortized over the purchase period. In April 2021, employees purchased 11,776 shares resulting in proceeds from the sale of common stock of $0.3 million under the ESPP for the first quarter of 2021.

Service-Based Stock Options

During the three months ended March 31, 2021 and 2020, the Company granted service-based options to purchase common stock of 1,337,955 and 1,186,140, respectively. The exercise price of the options is the fair market value per share of common stock on the grant date, and the options generally vest over four years (other than non-employee director options which vest over one year) and have a term of ten years. The Company issues new shares upon the exercise of stock options. The weighted average grant-date fair value of service-based options granted during the three months ended March 31, 2021 and 2020 was $32.02 and $8.64, respectively.

Restricted Stock Units

During the three months ended March 31, 2021 and 2020, the Company granted 214,113 and 186,136 service-based restricted stock units, respectively. The restricted stock units vest annually over four years in equal installments commencing on the first anniversary of the grant date (other than non-employee director options which vest over one year from the grant date). The Company issues new shares upon the vesting of restricted stock units. Restricted stock units are recorded at fair value at the date of grant, which is based on the closing share price on the grant date. Compensation expense is recorded for restricted stock units that are expected to vest based on their fair value at grant date and is amortized over the expected vesting period. The weighted average grant-date fair value of restricted stock units granted during the three months ended March 31, 2021 was $50.81, and $11.24 for the same period in 2020. The aggregate fair value of restricted stock units granted in the three months ended March 31, 2021 and 2020 was $10.9 million and $2.1 million, respectively.

During the three months ended March 31, 2021 and 2020, 47,857 and 22,340 shares, respectively of common stock were issued upon the vesting of restricted stock units. These amounts are net of 28,240 and 13,872 shares, respectively that were withheld for payment of taxes on the behalf of employees. For the three months ended March 31, 2021 and 2020 the total fair value of restricted stock awards vested was $4.1 million and $0.4 million, respectively. The total fair value of restricted stock units withheld for payment of taxes during the three months ended March 31, 2021 and 2020 was $1.5 million and $0.2 million, respectively.

Stock Compensation Expense

Non-cash stock-based compensation expense (employee stock purchase plan, service-based stock options and restricted stock units) included in cost of product sales, research and development expenses and selling, general and administrative expenses is summarized in the following table:


	Three Months Ended March 31,
(in thousands)	2021		2020
Cost of product sales	$	911	$	493
Research and development	863		513
Selling, general and administrative	5,245		2,762
Total non-cash stock-based compensation expense	$	7,019	$	3,768

Cash Equivalents and Investments

3 Months Ended

Mar. 31, 2021

Cash and Cash Equivalents [Abstract]

Cash Equivalents and 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, 2021 and December 31, 2020:


	March 31, 2021
			Gross Unrealized						Estimated Fair Value
	Amortized Cost		Gains		Losses		Credit Losses
Money market funds	$	15,598	$	—	$	—	$	—	$	15,598
Commercial paper	9,998		—		—		—		9,998
Corporate notes	40,082		—		(47)		—		40,035
U.S. government securities	1,500		—		—		—		1,500
U.S. government agency bonds	1,074		—		—		—		1,074
U.S. asset-backed securities	1,815		—		—		—		1,815
	$	70,067	$	—	$	(47)	$	—	$	70,020
Classified as:
Cash equivalents									$	18,597
Short-term investments									25,402
Long-term investments									26,021
									$	70,020


	December 31, 2020
			Gross Unrealized						Estimated Fair Value
(In thousands)	Amortized Cost		Gains		Losses		Credit Losses
Money market funds	$	3,698	$	—	$	—	$	—	$	3,698

Commercial paper	8,993		1		—		—		8,994
Corporate notes	35,917		—		—		(6)		35,911
U.S. government securities	12,828		14		—		—		12,842
U.S. government agency bonds	5,000		1		—		—		5,001
U.S. asset-backed securities	3,534		4		—		—		3,538
	$	69,970	$	20	$	—	$	(6)	$	69,984
Classified as:
Cash equivalents									$	3,698
Short-term investments									42,187
Long-term investments									24,099
									$	69,984

Investments classified as short-term have maturities of less than one year. Investments classified as long-term are those which: (i) have a maturity of greater than one year, and (ii) the Company does not intend to liquidate within the next twelve months, although these funds are available for use and, therefore, are classified as available-for-sale. The Company’s investment strategy is to buy short-duration marketable securities with a high credit rating. As of March 31, 2021 and December 31, 2020, all marketable securities held by the Company had remaining contractual maturities of three years or less.

Unrealized gains are included as a component of accumulated other comprehensive income in the condensed consolidated balance sheets and statements of stockholders’ equity and a component of total comprehensive income (loss) in the condensed consolidated statements of comprehensive loss, until realized. Unrealized losses are evaluated for impairment under ASC 326, Financial Instruments - Credit Losses, to determine if the impairment is credit-related or non credit-related. Credit-related impairment is recognized as an allowance on the balance sheet with a corresponding adjustment to earnings, and non credit-

related impairment is recognized in other comprehensive income (loss), net of taxes. There were no material realized losses on marketable securities during the three months ended March 31, 2021. There have been no impairments of the Company’s assets measured and carried at fair value during the three months ended March 31, 2021 or March 31, 2020, respectively.

Fair Value Measurements

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

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).

There was no movement between Level 1 and Level 2 or between Level 2 and Level 3 from December 31, 2020 to March 31, 2021. 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, corporate notes, U.S. government securities, U.S. government agency bonds and U.S. asset-backed securities 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. The following table summarizes the valuation of the Company’s financial instruments that are measured at fair value on a recurring basis:


	March 31, 2021								December 31, 2020
			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	$	15,598	$	15,598	$	—	$	—	$	3,698	$	3,698	$	—	$	—

Commercial paper	9,998		—		9,998		—		8,994		—		8,994		—
Corporate notes	40,035		—		40,035		—		35,911				35,911		—
U.S. government securities	1,500		—		1,500		—		12,842				12,842		—
U.S. government agency bonds	1,074		—		1,074		—		5,001				5,001		—
U.S. asset-backed securities	1,815		—		1,815		—		3,538				3,538		—
	$	70,020	$	15,598	$	54,422	$	—	$	69,984	$	3,698	$	66,286	$	—

The fair values of the cash equivalents and marketable securities are based on observable market prices.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Net Loss Per Common Share

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Net Loss Per Common Share

The following reflects the net loss attributable to common shareholders and share data used in the basic and diluted earnings per share computations using the two class method:


	Three Months Ended March 31,
(Amounts in thousands, except per share amounts)	2021		2020
Numerator:
Net loss	$	(3,289)	$	(4,705)
Denominator:
Weighted-average common shares outstanding (basic and diluted)	45,984		44,924

Net loss per share attributable to common shareholders (basic and diluted)	$	(0.07)	$	(0.10)



Anti-dilutive shares excluded from the calculation of diluted earnings per share(a) (amounts in millions):
Stock options	6.2		6.2
Restricted stock units	0.4		0.3

(a) Common equivalent shares are not included in the diluted per share calculation where the effect of their inclusion would be anti-dilutive.

Nexobrid License and Supply Agreements	3 Months Ended
Nexobrid License and Supply Agreements	Mar. 31, 2021
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 30, 2020, the Company announced MediWound's submission of a biologics license application (BLA) to the U.S. Food and Drug Administration (FDA) seeking the approval of NexoBrid. Subsequently, on September 16, 2020, the Company announced that the FDA has accepted the BLA for review and has assigned a Prescription Drug User Fee Act (PDUFA) target date of June 29, 2021. Pursuant to the terms of the license agreement, if the BLA is approved, MediWound will transfer the BLA to the Company and the Company will market NexoBrid in the U.S. Both MediWound and the Company, 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. NexoBrid is approved in the European Union and other international markets and has been designated as an orphan biologic in the United States, European Union and other international markets. In May 2019, the Company paid MediWound $17.5 million in consideration for the license. The $17.5 million upfront payment was recorded to research and development expense during 2019, as the license was considered in process research and development. 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 million contingent upon meeting certain sales milestones, subsequent to approval. 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 million. As of March 31, 2021, the milestone payments were not yet probable and therefore, not considered 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, following approval. 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. BARDA has committed to procure NexoBrid directly from MediWound under an emergency use authorization, and under such commitment the Company will receive a percentage of gross profit for sales directly to BARDA. If BARDA procures NexoBrid directly from the Company, the Company will pay a percentage of gross profits to MediWound on initial committed amounts and a royalty on any additional BARDA purchases of NexoBrid beyond the initial committed amount. As of March 31, 2021, the Company did not hold a direct contract or distribution agreement with BARDA. During 2020, BARDA accepted the first shipments of NexoBrid for emergency use preparedness per the agreement between BARDA and MediWound. During the three months ended March 31, 2021, the Company recognized $0.9 million of revenue. No revenue related to the procurement by BARDA was recognized for three months ended March 31, 2020.

Commitments and Contingencies

3 Months Ended

Mar. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

The Company's purchase commitments consist of minimum purchase amounts of materials used in the Company's cell manufacturing process to manufacture its marketed cell therapy products. In addition, the Company also pays for usage of an offsite warehouse space. In February 2021, the terms of the operating agreement were extended through March 31, 2027. The Company records rent expense related to this agreement on a straight-line basis over the remaining term.

Future minimum payments related to the Company's contractual obligations are as follows:


			Payments Due by Period
Contractual Obligations (in thousands)	Total		April 1, 2021 to December 31, 2021		2022		2023		2024		2025		More than 5 Years

Purchase commitments	$	9,504	$	8,853	$	651	$	—	$	—	$	—	$	—
Warehouse Operating Agreement	4,302		677		896		642		642		642		803
Total	$	13,806	$	9,530	$	1,547	$	642	$	642	$	642	$	803

Basis of Presentation (Policies)	3 Months Ended
Basis of Presentation (Policies)	Mar. 31, 2021
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Simplifying the Accounting for Income Taxes In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (ASC 740). The ASU enhances and simplifies various aspects of the income tax accounting guidance in ASC 740, including requirements related to hybrid tax regimes, the tax basis step-up in goodwill obtained in a transaction that is not a business combination, separate financial statements of entities not subject to tax, the intra-period tax allocation exception to the incremental approach, ownership changes in investments, changes from a subsidiary to an equity method investment, interim-period accounting for enacted changes in tax law, and the year-to-date loss limitation in interim-period tax accounting. This guidance became effective for the Company on January 1, 2021 and had no material impact on its Condensed Consolidated Financial Statements.

Basis of Presentation (Tables)

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Supplementary cash flows information

The following table presents certain supplementary cash flows information for the three months ended March 31, 2021 and 2020:


	Three Months Ended March 31,
(In thousands)	2021		2020
Supplementary Cash Flows information:
Non-cash information:

Right-of-use asset and lease liability recognized	$	—	$	326
Additions to property and equipment included in accounts payable	530		105
Restricted shares held for employee tax remittance included in accounts payable	65		66

Cash information:
Interest paid (net of interest capitalized)	$	1	$	2


	Three Months Ended March 31,
(In thousands)	2021		2020
Reconciliation of cash, cash equivalents, and restricted cash reported in the statement of financial position:
Cash and cash equivalents	$	58,154	$	45,623
Restricted cash, included in other long-term assets	211		89
Total cash, cash equivalents, and restricted cash shown in the statement of cash flows	$	58,365	$	45,712

Revenue (Tables)

3 Months Ended

Mar. 31, 2021

Risks and Uncertainties [Abstract]

Disaggregation of Revenue

The following table and description below shows the products from which the Company generated its revenue:


	Three Months Ended March 31,
Revenue by product (in thousands)	2021		2020
MACI implants and kits
Implants based on contracted rate sold through a specialty pharmacy (a)	$	13,206	$	11,338
Implants subject to third party reimbursement sold through a specialty pharmacy (b)	4,280		3,730
Implants sold direct based on contracted rates (c)	4,466		3,109
Implants sold direct subject to third party reimbursement (d)	849		436
Biopsy kits - direct bill	519		466
Change in estimates related to prior periods (e)	477		1,207
Epicel
Direct bill (hospital)	9,830		6,392

Total product revenue	$	33,627	$	26,678
NexoBrid revenue (f)	941		—
Total net revenue	$	34,568	$	26,678

(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 the 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 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 Components (Tables)

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

Schedule of inventory

Inventory as of March 31, 2021 and December 31, 2020:


(In thousands)	March 31, 2021		December 31, 2020
Raw materials	$	9,409	$	8,775
Work-in-process	884		537
Finished goods	29		44
Inventory	$	10,322	$	9,356

Schedule of property and equipment, net

Property and Equipment, net as of March 31, 2021 and December 31, 2020:


(In thousands)	March 31, 2021		December 31, 2020
Machinery and equipment	$	3,701	$	3,672
Furniture, fixtures and office equipment	810		809
Computer equipment and software	6,967		6,846
Leasehold improvements	5,594		5,560
Construction in process	4,071		2,021
Financing right-of-use lease	102		111
Total property and equipment, gross	21,245		19,019
Less accumulated depreciation	(12,169)		(11,386)
Property and equipment, net	$	9,076	$	7,633

Schedule of accrued expenses

Accrued Expenses as of March 31, 2021 and December 31, 2020 are as follows:


(In thousands)	March 31, 2021		December 31, 2020
Bonus related compensation	$	2,605	$	5,721
Employee related accruals	4,300		3,482
Other accrued expenses	3,060		2,090
Accrued expenses	$	9,965	$	11,293

Leases (Tables)

3 Months Ended

Mar. 31, 2021

Leases [Abstract]

Assets And Liabilities

Total leased assets and liabilities classified on the balance sheet, as of March 31, 2021 and December 31, 2020 are as follows:


(In thousands)	Classification	March 31, 2021		December 31, 2020
Assets
Operating	Right-of-use assets	$	48,943	$	50,105
Finance	Property and equipment, net	102		111
		$	49,045	$	50,216
Liabilities
Current
Operating	Current portion of operating lease liabilities	$	4,398	$	4,394
Finance	Other liabilities	41		41
		$	4,439	$	4,435
Non-current
Operating	Operating lease liabilities	$	47,968	$	48,789
Finance	Other long-term liabilities	57		76
		$	48,025	$	48,865

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

Schedule of non-cash stock-based compensation expense


	Three Months Ended March 31,
(in thousands)	2021		2020
Cost of product sales	$	911	$	493
Research and development	863		513
Selling, general and administrative	5,245		2,762
Total non-cash stock-based compensation expense	$	7,019	$	3,768

Cash Equivalents and Investments (Tables)

3 Months Ended

Mar. 31, 2021

Cash and Cash Equivalents [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, 2021 and December 31, 2020:


	March 31, 2021
			Gross Unrealized						Estimated Fair Value
	Amortized Cost		Gains		Losses		Credit Losses
Money market funds	$	15,598	$	—	$	—	$	—	$	15,598
Commercial paper	9,998		—		—		—		9,998
Corporate notes	40,082		—		(47)		—		40,035
U.S. government securities	1,500		—		—		—		1,500
U.S. government agency bonds	1,074		—		—		—		1,074
U.S. asset-backed securities	1,815		—		—		—		1,815
	$	70,067	$	—	$	(47)	$	—	$	70,020
Classified as:
Cash equivalents									$	18,597
Short-term investments									25,402
Long-term investments									26,021
									$	70,020


	December 31, 2020
			Gross Unrealized						Estimated Fair Value
(In thousands)	Amortized Cost		Gains		Losses		Credit Losses
Money market funds	$	3,698	$	—	$	—	$	—	$	3,698

Commercial paper	8,993		1		—		—		8,994
Corporate notes	35,917		—		—		(6)		35,911
U.S. government securities	12,828		14		—		—		12,842
U.S. government agency bonds	5,000		1		—		—		5,001
U.S. asset-backed securities	3,534		4		—		—		3,538
	$	69,970	$	20	$	—	$	(6)	$	69,984
Classified as:
Cash equivalents									$	3,698
Short-term investments									42,187
Long-term investments									24,099
									$	69,984

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2021

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


	March 31, 2021								December 31, 2020
			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	$	15,598	$	15,598	$	—	$	—	$	3,698	$	3,698	$	—	$	—

Commercial paper	9,998		—		9,998		—		8,994		—		8,994		—
Corporate notes	40,035		—		40,035		—		35,911				35,911		—
U.S. government securities	1,500		—		1,500		—		12,842				12,842		—
U.S. government agency bonds	1,074		—		1,074		—		5,001				5,001		—
U.S. asset-backed securities	1,815		—		1,815		—		3,538				3,538		—
	$	70,020	$	15,598	$	54,422	$	—	$	69,984	$	3,698	$	66,286	$	—

Net Loss Per Common Share (Tables)

3 Months Ended

Mar. 31, 2021

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

The following reflects the net loss attributable to common shareholders and share data used in the basic and diluted earnings per share computations using the two class method:


	Three Months Ended March 31,
(Amounts in thousands, except per share amounts)	2021		2020
Numerator:
Net loss	$	(3,289)	$	(4,705)
Denominator:
Weighted-average common shares outstanding (basic and diluted)	45,984		44,924

Net loss per share attributable to common shareholders (basic and diluted)	$	(0.07)	$	(0.10)



Anti-dilutive shares excluded from the calculation of diluted earnings per share(a) (amounts in millions):
Stock options	6.2		6.2
Restricted stock units	0.4		0.3

(a) Common equivalent shares are not included in the diluted per share calculation where the effect of their inclusion would be anti-dilutive.

Commitments and Contingencies (Tables)

3 Months Ended

Mar. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Future Minimum Payments Related to Contractual Obligations

Future minimum payments related to the Company's contractual obligations are as follows:


			Payments Due by Period
Contractual Obligations (in thousands)	Total		April 1, 2021 to December 31, 2021		2022		2023		2024		2025		More than 5 Years

Purchase commitments	$	9,504	$	8,853	$	651	$	—	$	—	$	—	$	—
Warehouse Operating Agreement	4,302		677		896		642		642		642		803
Total	$	13,806	$	9,530	$	1,547	$	642	$	642	$	642	$	803

Organization - Narrative (Details) $ in Thousands	3 Months Ended
Organization - Narrative (Details) $ in Thousands	Mar. 31, 2021 USD ($) product segment	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of therapy products \| product	2
Number of reportable segments \| segment	1
Net (loss) income	$ (3,289)	$ (4,705)
Accumulated deficit	379,104		$ 375,815
Cash and cash equivalents	58,154	$ 45,623	$ 33,620
Short term investments	$ 51,400

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Basis of Presentation - Supplementary cash flows information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Non-cash information:
Right-of-use asset and lease liability recognized	$ 0	$ 326
Additions to property and equipment included in accounts payable	530	105
Restricted shares held for employee tax remittance included in accounts payable	65	66
Interest paid (net of interest capitalized)	$ 1	$ 2

Basis of Presentation - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and cash equivalents	$ 58,154	$ 33,620	$ 45,623
Restricted cash, included in other long-term assets	211		89
Total cash, cash equivalents, and restricted cash shown in the statement of cash flows	$ 58,365	$ 33,831	$ 45,712	$ 26,978

Revenue (Details)	3 Months Ended
Revenue (Details)	Mar. 31, 2021 USD ($) pharmacy	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
CONCENTRATION
Number of specialty pharmacies \| pharmacy	2
Allowance for doubtful accounts	$ 6,100,000		$ 5,300,000
Change in estimate of uncollectible (percent)	0.50%
Change in revenue recognized due to 0.5% change in uncollectible percentage	$ 200,000
Increase (decrease) to revenues	33,627,000	$ 26,678,000
Other revenue recognized	941,000	0
NexoBrid
CONCENTRATION
Other revenue recognized	900,000	0
NexoBrid \| Provider or Facility
CONCENTRATION
Other revenue recognized	941,000	0
Accounting Standards Update 2014-09 \| Difference between Revenue Guidance in Effect before and after Topic 606
CONCENTRATION
Increase (decrease) to revenues	477,000	$ 1,207,000
COVID-19 potential impacts
CONCENTRATION
Allowance related to the potential impacts of COVID-19 (less than)			$ 100,000
Additional allowance recorded	$ 0

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Product sales, net	$ 33,627	$ 26,678
Other revenue	941	0
Total revenue	34,568	26,678
Accounting Standards Update 2014-09 \| Difference between Revenue Guidance in Effect before and after Topic 606
Disaggregation of Revenue [Line Items]
Product sales, net	477	1,207
MACI Implants and Kits, and Epicel
Disaggregation of Revenue [Line Items]
Product sales, net	33,627	26,678
NexoBid revenue
Disaggregation of Revenue [Line Items]
Other revenue	900	0
Through Intermediary \| Implants \| Contract rate
Disaggregation of Revenue [Line Items]
Product sales, net	13,206	11,338
Through Intermediary \| Implants \| Time-and-materials contract
Disaggregation of Revenue [Line Items]
Product sales, net	4,280	3,730
Time-and-materials contract \| Implants \| Time-and-materials contract
Disaggregation of Revenue [Line Items]
Product sales, net	849	436
Provider or Facility \| Implants \| Contract rate
Disaggregation of Revenue [Line Items]
Product sales, net	4,466	3,109
Provider or Facility \| NexoBid revenue
Disaggregation of Revenue [Line Items]
Other revenue	941	0
Directly to consumer \| Biopsy kits
Disaggregation of Revenue [Line Items]
Product sales, net	519	466
Directly to consumer \| Epicel
Disaggregation of Revenue [Line Items]
Product sales, net	$ 9,830	$ 6,392

Revenue - Schedules of concentration of risk (Details)	3 Months Ended
Revenue - Schedules of concentration of risk (Details)	Mar. 31, 2021	Mar. 31, 2020
Revenue Concentration \| Customer concentration \| Epicel
Product Information [Line Items]
Concentration risk (as a percent)	14.00%	12.00%

Selected Balance Sheet Components - Schedule of inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Inventory:
Raw materials	$ 9,409	$ 8,775
Work-in-process	884	537
Finished goods	29	44
Inventory	$ 10,322	$ 9,356

Selected Balance Sheet Components - Schedule of property and equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Property and equipment, net:
Financing right-of-use lease	$ 102		$ 111
Total property and equipment, gross	21,245		19,019
Less accumulated depreciation	(12,169)		(11,386)
Property and equipment, net	9,076		7,633
Depreciation expense	800	$ 500
Machinery and equipment
Property and equipment, net:
Total property and equipment, gross	3,701		3,672
Furniture, fixtures and office equipment
Property and equipment, net:
Total property and equipment, gross	810		809
Computer equipment and software
Property and equipment, net:
Total property and equipment, gross	6,967		6,846
Leasehold improvements
Property and equipment, net:
Total property and equipment, gross	5,594		5,560
Construction in process
Property and equipment, net:
Total property and equipment, gross	$ 4,071		$ 2,021

Selected Balance Sheet Components - Schedule of accrued expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued expenses
Bonus related compensation	$ 2,605	$ 5,721
Employee related accruals	4,300	3,482
Other accrued expenses	3,060	2,090
Accrued expenses	$ 9,965	$ 11,293

Leases - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
Leases - Narrative (Details) - USD ($) $ in Millions	Oct. 21, 2020	Mar. 31, 2021	Mar. 31, 2020
Lessee, Lease, Description [Line Items]
Short-term lease costs (less than)		$ 0.1	$ 0.1
Operating lease expense		1.9	1.4
Finance lease expense		0.1	$ 0.1
Leasehold improvements
Lessee, Lease, Description [Line Items]
Leasehold improvements recorded		$ 0.2
Cambridge, Massachusetts
Lessee, Lease, Description [Line Items]
Tenant improvement allowance	$ 4.3
Minimum \| Cambridge, Massachusetts
Lessee, Lease, Description [Line Items]
Contractual lease payments	0.4
Maximum \| Cambridge, Massachusetts
Lessee, Lease, Description [Line Items]
Contractual lease payments	$ 0.6

Leases - Assets And Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Operating	$ 48,943	$ 50,105
Finance	102	111
Right-of-use assets	49,045	50,216
Current
Operating	4,398	4,394
Finance	41	41
Lease liability current	4,439	4,435
Non-current
Operating	47,968	48,789
Finance	57	76
Lease liability noncurrent	$ 48,025	$ 48,865
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesCurrent
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesNoncurrent

Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		75 Months Ended
	Apr. 30, 2021	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021
Stock-Based Compensation
Shares issued under the Employee Stock Purchase Plan (in shares)		$ 249	$ 224
Fair value of restricted stock units withheld for payment of taxes		$ 1,501	$ 163
Employee stock
Stock-Based Compensation
Common stock available for issuance (in shares)		1,000,000		1,000,000
Common stock granted since inception (in shares)				720,228
Employee stock \| Subsequent event
Stock-Based Compensation
Shares purchased during period (in shares)	11,776
Shares issued under the Employee Stock Purchase Plan (in shares)	$ 300
Service-based stock options
Stock-Based Compensation
Expiration period		10 years
Vesting period		4 years
Granted (in shares)		1,337,955	1,186,140
Weighted average grant-date fair value (in dollars per share)		$ 32.02	$ 8.64
Service-based stock options \| Nonemployee directors
Stock-Based Compensation
Expiration period		10 years
Vesting period		1 year
Restricted Stock Units (RSUs)
Stock-Based Compensation
Vesting period		4 years
Restricted stock units granted (shares)		214,113	186,136
Weighted-average grant date fair value (in usd per share)		$ 50.81	$ 11.24
Grant-date fair value of restricted stock units granted		$ 10,900	$ 2,100
Shares vested in period (shares)		47,857	22,340
Restricted stock withheld for employee tax remittance (in shares)		28,240	13,872
Fair value of vested restricted stock awards		$ 4,100	$ 400
Fair value of restricted stock units withheld for payment of taxes		$ 1,500	$ 200
Restricted Stock Units (RSUs) \| Nonemployee directors
Stock-Based Compensation
Vesting period		1 year
Common Stock
Stock-Based Compensation
Shares purchased during period (in shares)		14,000	20,000
Shares issued under the Employee Stock Purchase Plan (in shares)		$ 249	$ 224
Restricted stock withheld for employee tax remittance (in shares)		28,000	14,000
Fair value of restricted stock units withheld for payment of taxes		$ 1,501	$ 163
Prior Plans
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		0		0
Omnibus Incentive Plan 2019
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		2,942,648		2,942,648

Stock-Based Compensation - Schedule of non-cash stock-based compensation expense (Details) - Employee stock purchase plan and service-based stock options - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	$ 7,019	$ 3,768
Cost of product sales
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	911	493
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	863	513
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	$ 5,245	$ 2,762

Cash Equivalents and Investments (Details) - USD ($)	3 Months Ended	12 Months Ended
Cash Equivalents and Investments (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Marketable Securities [Line Items]
Amortized Cost	$ 70,067,000	$ 69,970,000
Gains	0	20,000
Losses	(47,000)	0
Credit Losses	0	(6,000)
Estimated Fair Value	$ 70,020,000	$ 69,984,000
Remaining contractual maturity period	3 years	3 years
Impairments of assets	$ 0
Cash equivalents
Marketable Securities [Line Items]
Estimated Fair Value	18,597,000	$ 3,698,000
Short-term investments
Marketable Securities [Line Items]
Estimated Fair Value	25,402,000	42,187,000
Long-term investments
Marketable Securities [Line Items]
Estimated Fair Value	26,021,000	24,099,000
Money market funds
Marketable Securities [Line Items]
Amortized Cost	15,598,000	3,698,000
Gains	0	0
Losses	0	0
Credit Losses	0	0
Estimated Fair Value	15,598,000	3,698,000
Commercial paper
Marketable Securities [Line Items]
Amortized Cost	9,998,000	8,993,000
Gains	0	1,000
Losses	0	0
Credit Losses	0	0
Estimated Fair Value	9,998,000	8,994,000
Corporate notes
Marketable Securities [Line Items]
Amortized Cost	40,082,000	35,917,000
Gains	0	0
Losses	(47,000)	0
Credit Losses	0	(6,000)
Estimated Fair Value	40,035,000	35,911,000
U.S. government securities
Marketable Securities [Line Items]
Amortized Cost	1,500,000	12,828,000
Gains	0	14,000
Losses	0	0
Credit Losses	0	0
Estimated Fair Value	1,500,000	12,842,000
U.S. government agency bonds
Marketable Securities [Line Items]
Amortized Cost	1,074,000	5,000,000
Gains	0	1,000
Losses	0	0
Credit Losses	0	0
Estimated Fair Value	1,074,000	5,001,000
U.S. asset-backed securities
Marketable Securities [Line Items]
Amortized Cost	1,815,000	3,534,000
Gains	0	4,000
Losses	0	0
Credit Losses	0	0
Estimated Fair Value	$ 1,815,000	$ 3,538,000

Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	$ 70,020	$ 69,984
Recurring
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	70,020	69,984
Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	15,598	3,698
Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	54,422	66,286
Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	0	0
Commercial paper \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	9,998	8,994
Commercial paper \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Commercial paper \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	9,998	8,994
Commercial paper \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Corporate Note Securities \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	40,035	35,911
Corporate Note Securities \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0
Corporate Note Securities \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	40,035	35,911
Corporate Note Securities \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
U.S. government securities
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,500	12,842
U.S. government securities \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,500	12,842
U.S. government securities \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0
U.S. government securities \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,500	12,842
U.S. government securities \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
U.S. government agency bonds
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,074	5,001
U.S. government agency bonds \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,074	5,001
U.S. government agency bonds \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0
U.S. government agency bonds \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,074	5,001
U.S. government agency bonds \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Asset-backed Securities
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,815	3,538
Asset-backed Securities \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,815	3,538
Asset-backed Securities \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0
Asset-backed Securities \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	1,815	3,538
Asset-backed Securities \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Money market funds \| Recurring
Liabilities that are measured at fair value on a recurring basis
Money market funds	15,598	3,698
Money market funds \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Money market funds	15,598	3,698
Money market funds \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Money market funds	0	0
Money market funds \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Money market funds	$ 0	$ 0

Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss	$ (3,289)	$ (4,705)
Weighted average number of common shares outstanding (basic) (in shares)	45,984	44,924
Weighted average number of common shares outstanding (diluted) (in shares)	45,984	44,924
Net loss per share (basic) (in USD per share)	$ (0.07)	$ (0.10)
Net loss per share (diluted) (in USD per share)	$ (0.07)	$ (0.10)
Service-based stock options
Anti-dilutive shares excluded from the calculation of diluted earnings per share(a) (amounts in millions):
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)	6,200	6,200
Restricted Stock Units (RSUs)
Anti-dilutive shares excluded from the calculation of diluted earnings per share(a) (amounts in millions):
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)	400	300

Nexobrid License and Supply Agreements (Details) - MediWound Ltd $ in Millions	1 Months Ended
	May 31, 2019 USD ($)
Related Party Transaction [Line Items]
Consideration payment for license	$ 17.5
Payable	17.5
Contingent consideration	7.5
Max contingent consideration	125.0
Sales Initial milestone	$ 75.0
Term of supply agreement	5 years

Commitments and Contingencies - Future Minimum Payments (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Purchase commitments
Total	$ 9,504
April 1, 2021 to December 31, 2021	8,853
2022	651
2023	0
2024	0
2025	0
More than 5 Years	0
Operating Leases
Total	4,302
April 1, 2021 to December 31, 2021	677
2022	896
2023	642
2024	642
2025	642
More than 5 Years	803
Contractual Obligation, Fiscal Year Maturity [Abstract]
Total	13,806
April 1, 2021 to December 31, 2021	9,530
2022	1,547
2023	642
2024	642
2025	642
More than 5 Years	$ 803