In October 2019, the Company entered into a noncancelable facility lease agreement (the “the 2019 Lease”) for 34,522 square feet of research and development and office space in Watertown, Massachusetts. The term of the 2019 Lease is 120 months and expires on March 31, 2030. The 2019 Lease has an option to be extended for an additional five years. The lease is not reasonably certain to be extended and as such the additional term is not included in the measurement of the lease. The 2019 Lease includes a rent escalation clause, and rent expense is being recorded on a straight-line basis. In accordance with the lease agreement, the Company is required to maintain a security deposit and provided a letter of credit to the landlord for $1.6 million, which is recorded in restricted cash as of June 30, 2022 and December 31, 2021.

In December 2021, the Company entered into a noncancelable lease (the "2021 Lease") for 100,624 square feet of office and laboratory space in Watertown, Massachusetts, which the Company expects to begin occupying in November 2023. The 2021 Lease is subject to base rent of $0.8 million per month beginning two months after the commencement date, plus the Company’s ratable share of taxes, maintenance and other operating expenses. Base rent is subject to a 3% annual increase over the lease term of approximately 134 months following the commencement date. The Company also has two consecutive options to extend the term of the lease for five years each at then-market rates. The 2021 Lease also includes a tenant improvement allowance of approximately $20.1 million. In connection with the signing of the 2021 Lease, the Company issued a letter of credit for $4.5 million which is classified as restricted cash as of June 30, 2022 and December 31, 2021. The Company also paid first month’s rent of $0.8 million upon execution of the 2021 Lease in December 2021 which is classified as other non-current assets as of June 30, 2022 and December 31, 2021. As of June 30, 2022, the Company has not taken control of the space associated with the 2021 Lease and therefore, the Company has not recorded a right of use asset or lease liability related to the space as of June 30, 2022.

The Company’s finance lease obligations consist of certain property and equipment financed through finance leases.

The components of the lease costs for the three and six months ended June 30, 2022 and 2021, were as follows (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Operating lease costs	$	524	$	524	$	1,047	$	1,047
Finance lease costs:
Amortization of right-to-use assets, finance leases		279		193		558		371
Interest expense for finance lease liabilities		40		21		86		37
Variable lease costs		244		153		573		385
Total lease costs	$	1,087	$	891	$	2,264	$	1,840

Supplemental cash flow information relating to the Company’s leases for the six months ended June 30, 2022 and 2021, were as follows (in thousands):


	Six Months Ended June 30,
	2022		2021
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows used in operating leases	$	1,281	$	1,428
Operating cash flows used in finance leases	$	489	$	350
Financing cash flows used in finance leases	$	86	$	37

Weighted average remaining lease terms and discount rates as of June 30, 2022 and 2021 were as follows:


	Six Months Ended June 30,
	2022			2021
Remaining lease term:
Operating lease	7.84 years			8.84 years
Finance lease	1.79 years			2.68 years
Discount Rate:
Operating lease		10.50	%		10.50	%
Finance lease		8.74	%		8.51	%

The undiscounted future lease payments for operating and finance leases as of June 30, 2022, were as follows (in thousands):


Fiscal Year	Operating Leases			Finance Leases
2022 (excluding the first and second quarters)	$	1,300		$	628
2023		2,659			1,097
2024		2,732			473
2025		2,814			64
2026		2,898			—
Thereafter		10,027			—
Total minimum lease payments		22,430			2,262
Less amounts representing interest or imputed interest		(7,224	)		(177	)
Present value of lease liabilities	$	15,206		$	2,085

Excluded from the table above are all future payments related to the 2021 Lease.