On May 17, 2018, the Company amended the lease for its headquarters in Watertown, Massachusetts. The original five-year lease for approximately 13,650 square feet of combined office and laboratory space was set to expire in April 2019. Under the amendment, the Company leased an additional 6,590 square feet of rentable area of the building, with a commencement date of September 10, 2018. The amendment extended the term of the lease for the combined space through May 31, 2025, and the landlord provided the Company a construction allowance of up to $670,750 to be applied toward renovations and improvements within the total space. On April 5, 2021, the Company further amended the lease to include an additional 1,409 square feet of rentable area of the building through May 31, 2025, with a commencement date of July 1, 2021. On March 8, 2022, the Company further amended the lease (i) to extend the term to May 31, 2028 for 13,650 square feet of laboratory and manufacturing operations space, with the landlord agreeing to provide the Company a construction allowance of up to $555,960 to be applied toward upgrades and improvements within the space; (ii) to rent an additional 11,999 square feet of office space within the building through May 31, 2028, with an anticipated commencement date in the third quarter of 2022; and (iii) to terminate a portion of the lease comprising 7,999 square feet of office space in the building on May 31, 2025. The Company previously provided a cash-collateralized $150,000 irrevocable standby letter of credit as security for the Company’s obligations under the lease, which will remain in effect through the period that is four months beyond the expiration date of the amended lease. The Company will also be required to pay its proportionate share of certain operating costs and property taxes applicable to the leased premises in excess of new base year amounts.

In July 2017, the Company leased approximately 3,000 square feet of office space in Basking Ridge, New Jersey under a lease term extending through June 2022, with two five-year renewal options at 95% of the then-prevailing market rates. In addition to base rent, the Company is obligated to pay its proportionate share of building operating expenses and real estate taxes in excess of base year amounts. In June 2018, the Company subleased an additional 1,381 square feet of adjoining space from Caladrius Biosciences, Inc. (“Caladrius”) through May 2022. The Chief Executive Officer of Caladrius was a director of the Company through June 2020. Per the terms of the lease and sublease agreements, the Company does not have any residual value guarantees. The Company has given notice that the Company will not be renewing this lease and the Company will vacate the facility upon expiration.

The Company identified and assessed the following significant assumptions in recognizing its right-of-use (“ROU”) assets and corresponding lease liabilities:

As of December 31, 2021, the weighted average remaining term of the Company’s operating leases was 3.4 years and the lease liabilities arising from obtaining ROU assets reflect a weighted average discount rate of 12.5%.

Supplemental balance sheet information related to operating leases as of December 31, 2021 and 2020, respectively are as follows (in thousands):

	December 31,		December 31,
	2021		2020
Other current liabilities - operating lease current portion	$	645	$	568
Operating lease liabilities – noncurrent portion		1,860		2,330
Total operating lease liabilities	$	2,505	$	2,898

Operating lease expense recognized related to ROU assets was $885,000 and $852,000, excluding $30,000 and $36,000 of variable lease costs, during each of the years ended December 31, 2021 and 2020, respectively, and were included in general and administrative expense in the Company’s statement of comprehensive loss. Cash paid for amounts included in the measurement of operating lease liabilities was $920,000 and $867,000 for the years ended December 31, 2021 and 2020, respectively.

The Company is a party to three finance leases for laboratory equipment. The equipment leases expire in December 2021, December 2022 and June 2023, respectively.

Supplemental balance sheet information related to the finance lease as of December 31, 2021 and 2020, respectively are as follows (in thousands):

	December 31,			December 31,
	2021			2020
Property and equipment, at cost	$	371		$	239
Accumulated amortization		(205	)		(52	)
Property and equipment, net	$	166		$	187

Other current liabilities – finance lease current portion	$	137		$	119
Other long-term liabilities		36			71
Total finance lease liabilities	$	173		$	190

The components of finance lease expense recognized during the years ended December 31, 2021 and 2020 related to ROU assets were $151,000 and $52,000, respectively. Interest on lease liabilities were $23,000 and $9,000 during the years ended December 31, 2021 and 2020, respectively. Cash paid for amounts included in the measurement of finance lease liabilities was operating cash flows of $23,000 and financing cash flows of $146,000 during the year ended December 31, 2021, respectively. Cash paid for amounts included in the measurement of finance lease liabilities was operating cash flows of $9,000 and financing cash flows of $49,000 during the year ended December 31, 2020, respectively.

As of December 31, 2021, the weighted average remaining term of the Company’s finance lease was 1.3 years and the lease liabilities arising from obtaining ROU assets reflect a weighted average discount rate of 12.5%.

The Company’s total future minimum lease payments under non-cancellable leases at December 31, 2021 were as follows (in thousands):

	Operating Leases			Finance Leases
2022		911			149
2023		877			37
2024		894			—
2025		373			—
Total lease payments	$	3,055		$	186
Less imputed interest		(550	)		(13	)
Total	$	2,505		$	173