Leases

12 Months Ended

Dec. 31, 2025

Leases [Abstract]

Leases

Leases

The Company leases facilities in Ann Arbor, Michigan, Cambridge, Massachusetts and Burlington, Massachusetts. The Ann Arbor facility includes office space, and the Cambridge facility includes clean rooms, laboratories for MACI and Epicel manufacturing and office space. The Company also leases certain equipment.

On January 28, 2022, the Company entered into a lease agreement (as amended, the “Burlington Lease”) to lease approximately 126,000 square feet of manufacturing, laboratory and office space in Burlington, Massachusetts (the “Premises”). The Burlington facility is complete, and the Company is currently utilizing the facility’s office space. The remaining tenant improvements to the manufacturing suites and related equipment will be placed in service when they are ready for their intended uses. Once validated, the facility’s manufacturing component will eventually become the primary manufacturing facility for MACI and Epicel.

In April 2023, in connection with the Burlington Lease, the Company entered into a construction escrow agreement (the “Construction Escrow Agreement”) with the facility’s landlord and an escrow agent. Pursuant to the terms of the Construction Escrow Agreement, in April 2023, the Company began funding, into an escrow account maintained by the escrow agent, a portion of its share of tenant improvement construction costs at the facility, which were designated as restricted cash. At the same time, the facility’s landlord began funding a portion of its tenant improvement allowance through a separate escrow account. The Company funded the remaining 50% of its required cost amount, or approximately $28.3 million, with cash on hand, pursuant to the Construction Escrow Agreement in April 2024. During the second quarter of 2025, the amounts deposited by the Company into its escrow account pursuant to the Construction Escrow Agreement were disbursed. The Company’s escrow account is now closed and approximately $5.2 million, which remained in the Company’s escrow account at the time of closure, was returned to the Company and is no longer restricted cash.

The Company has determined that certain improvements to the Premises are landlord-owned improvements and costs incurred for these improvements are accounted for as a variable lease payment. In the year ended December 31, 2024, the Company recorded a right-of-use asset related to landlord-owned improvements incurred of approximately $3.6 million.

For the years ended December 31, 2025 and 2024, lease expense of $0.3 million, and for the year ended December 31, 2023, lease expense of less than $0.1 million, was recorded related to short-term leases. For the years ended December 31, 2025, 2024 and 2023, the Company recognized $11.9 million, $12.7 million and $10.3 million, respectively, of operating lease expense. For the years ended December 31, 2025, 2024 and 2023, the Company recognized less than $0.1 million of financing lease expense.

Operating and finance lease assets and liabilities are as follows:

		December 31,
(In thousands)	Classification	2025		2024
Assets
Operating	Right-of-use assets	$	64,774	$	70,098
Finance	Property and equipment, net	686		686
Total leased assets		$	65,460	$	70,784
Liabilities
Current
Operating	Current portion of operating lease liabilities	$	13,969	$	9,257
Finance	Other current liabilities	116		116
Non-current
Operating	Operating lease liabilities	82,284		89,593
Finance	Other long-term liabilities	522		570
Total leased liabilities		$	96,891	$	99,536

Cash paid for amounts included in the measurement of the Company’s operating lease liabilities was $9.3 million and $1.7 million for the years ended December 31, 2025 and 2023, respectively. Cash received for amounts included in the measurement of the Company’s operating lease liabilities was $1.4 million for the year ended December 31, 2024. Cash paid for amounts included in the measurement of the Company’s finance lease liabilities was less than $0.1 million for the year ended December 31, 2025.

Future minimum lease payments under non-cancellable leases as of December 31, 2025 are as follows:

(In thousands)	Operating Leases		Finance Leases		Total
2026	$	13,969	$	116	$	14,085
2027	14,351		116		14,467
2028	14,743		116		14,859
2029	15,146		116		15,262
2030	15,561		116		15,677
Thereafter	57,779		167		57,946
Total lease payments	$	131,549	$	747	$	132,296
Less: interest	(35,296)		(109)		(35,405)
Present value of lease liabilities	$	96,253	$	638	$	96,891

Lease terms and discount rates are as follows:

	December 31,
	2025	2024
Weighted-average remaining lease term (years)
Operating leases	8.8	9.7
Finance leases	6.4	6.9
Weighted-average discount rate
Operating leases	6.9%	6.9%
Finance leases	5.0%	5.0%

Leases

Leases

The Company leases facilities in Ann Arbor, Michigan, Cambridge, Massachusetts and Burlington, Massachusetts. The Ann Arbor facility includes office space, and the Cambridge facility includes clean rooms, laboratories for MACI and Epicel manufacturing and office space. The Company also leases certain equipment.

On January 28, 2022, the Company entered into a lease agreement (as amended, the “Burlington Lease”) to lease approximately 126,000 square feet of manufacturing, laboratory and office space in Burlington, Massachusetts (the “Premises”). The Burlington facility is complete, and the Company is currently utilizing the facility’s office space. The remaining tenant improvements to the manufacturing suites and related equipment will be placed in service when they are ready for their intended uses. Once validated, the facility’s manufacturing component will eventually become the primary manufacturing facility for MACI and Epicel.

In April 2023, in connection with the Burlington Lease, the Company entered into a construction escrow agreement (the “Construction Escrow Agreement”) with the facility’s landlord and an escrow agent. Pursuant to the terms of the Construction Escrow Agreement, in April 2023, the Company began funding, into an escrow account maintained by the escrow agent, a portion of its share of tenant improvement construction costs at the facility, which were designated as restricted cash. At the same time, the facility’s landlord began funding a portion of its tenant improvement allowance through a separate escrow account. The Company funded the remaining 50% of its required cost amount, or approximately $28.3 million, with cash on hand, pursuant to the Construction Escrow Agreement in April 2024. During the second quarter of 2025, the amounts deposited by the Company into its escrow account pursuant to the Construction Escrow Agreement were disbursed. The Company’s escrow account is now closed and approximately $5.2 million, which remained in the Company’s escrow account at the time of closure, was returned to the Company and is no longer restricted cash.

The Company has determined that certain improvements to the Premises are landlord-owned improvements and costs incurred for these improvements are accounted for as a variable lease payment. In the year ended December 31, 2024, the Company recorded a right-of-use asset related to landlord-owned improvements incurred of approximately $3.6 million.

For the years ended December 31, 2025 and 2024, lease expense of $0.3 million, and for the year ended December 31, 2023, lease expense of less than $0.1 million, was recorded related to short-term leases. For the years ended December 31, 2025, 2024 and 2023, the Company recognized $11.9 million, $12.7 million and $10.3 million, respectively, of operating lease expense. For the years ended December 31, 2025, 2024 and 2023, the Company recognized less than $0.1 million of financing lease expense.

Operating and finance lease assets and liabilities are as follows:

		December 31,
(In thousands)	Classification	2025		2024
Assets
Operating	Right-of-use assets	$	64,774	$	70,098
Finance	Property and equipment, net	686		686
Total leased assets		$	65,460	$	70,784
Liabilities
Current
Operating	Current portion of operating lease liabilities	$	13,969	$	9,257
Finance	Other current liabilities	116		116
Non-current
Operating	Operating lease liabilities	82,284		89,593
Finance	Other long-term liabilities	522		570
Total leased liabilities		$	96,891	$	99,536

Cash paid for amounts included in the measurement of the Company’s operating lease liabilities was $9.3 million and $1.7 million for the years ended December 31, 2025 and 2023, respectively. Cash received for amounts included in the measurement of the Company’s operating lease liabilities was $1.4 million for the year ended December 31, 2024. Cash paid for amounts included in the measurement of the Company’s finance lease liabilities was less than $0.1 million for the year ended December 31, 2025.

Future minimum lease payments under non-cancellable leases as of December 31, 2025 are as follows:

(In thousands)	Operating Leases		Finance Leases		Total
2026	$	13,969	$	116	$	14,085
2027	14,351		116		14,467
2028	14,743		116		14,859
2029	15,146		116		15,262
2030	15,561		116		15,677
Thereafter	57,779		167		57,946
Total lease payments	$	131,549	$	747	$	132,296
Less: interest	(35,296)		(109)		(35,405)
Present value of lease liabilities	$	96,253	$	638	$	96,891

Lease terms and discount rates are as follows:

	December 31,
	2025	2024
Weighted-average remaining lease term (years)
Operating leases	8.8	9.7
Finance leases	6.4	6.9
Weighted-average discount rate
Operating leases	6.9%	6.9%
Finance leases	5.0%	5.0%