In August 2007, the Company entered into an operating lease, as amended, for approximately 22,343 square feet of office and laboratory space in Watertown, Massachusetts. In November 2017, the Company amended its lease (“2017 Amendment”) and extended the lease term through April 2023. Initial base rent under the 2017 Amendment was approximately $1.0 million per year. The 2017 Amendment includes annual rent escalations over the term of the operating lease. The Company maintains a letter of credit of approximately $0.3 million securing its obligations under the operating lease which is secured by approximately $0.3 million of certificate of deposits, which are included as restricted cash in the consolidated balance sheets. Rent expense is recognized on a straight-line basis over the terms of occupancy.

In addition to the lease discussed above, the Company is party to an April 2020 lease for office equipment that expires in June 2024. The equipment lease is accounted for as an operating lease.

In April 2021, the Company entered into a clinical supply agreement with a contract manufacturing organization (“CMO”) for clinical production of the Company’s product candidates at an existing facility and a facility under construction. The Company concluded that this clinical supply agreement contains embedded operating leases as the clean rooms in the existing facility and the new facility are designated for the Company’s exclusive use during the term of the agreement and the clinical supply agreement contains fixed commitments and variable costs related to production and material costs in excess of the fixed commitment specified in the agreement. The Company determined that it did not control the new facility during construction and, thus, the lease did not fall in the scope of “build-to-suit” accounting. The term of the clinical supply agreement is five years and will automatically renew for additional successive terms of one year unless either party gives notice of nonrenewal.

The lease period for the existing facility is less than 12 months and the Company has elected to apply the practical expedient in ASC Topic 842, Leases (“ASC 842”), to not recognize a lease liability or right-of-use asset but instead, recognize lease payments as an expense on a straight-line basis over the lease term and variable lease payments that do not depend on an index or rate, as an expense in the period in which the variable lease costs are incurred based on performance or usage in accordance with the clinical supply agreement.

At the inception of the new facility lease, the Company determined the fixed commitment specified in the purchase order issued under the clinical supply agreement was not material and did not recognize a lease liability and right-of-use asset. The lease costs under this purchase order will be recognized as expense in the period in which the lease costs are incurred based on performance or usage in accordance with the purchase order. In the future, the Company will purchase product in batches from the CMO in quantities to be set forth on purchase orders submitted to the CMO, within a certain time period, prior to the requested date of delivery. The quantities of product ordered on each purchase order are binding obligations to purchase from the CMO and considered fixed commitments and the Company will recognize the appropriate lease liability and right-of-use asset at that time.

The components of lease cost recorded in the Company’s condensed consolidated financial statements were as follows (in thousands):


	Three Months Ended March 31,
	2022		2021
Lease Cost:
Operating lease cost	$	264	$	264
Variable lease cost		878		119
Total lease cost	$	1,142	$	383

Variable lease payments include the Company’s allocated share of costs incurred and expenditures made by the landlord in the operation and management of the building and variable lease costs associated with the Company’s CMO embedded lease arrangement. During the three months ended March 31, 2022 and 2021, the Company recorded as research and development expense approximately $0.7 million and $0 of operating lease costs related to the CMO embedded lease, respectively.

The weighted-average remaining lease term and discount rate related to the Company’s operating leases were as follows:


	As of March 31, 2022
Weighted-average remaining lease term (in years)		1.1
Weighted-average discount rate		5.5	%

Maturity of the Company’s operating lease liabilities in accordance with ASC 842 as of March 31, 2022 were as follows (in thousands):


Year ending December 31,
Remainder of 2022	$	851
2023		382
2024		2
Total maturities		1,235
Less: Amount representing interest		(39	)
Present value of operating lease liability		1,196
Less: Current portion of operating lease liability		(1,097	)
Total operating lease liability, net of current portion	$	99