In February 2018, the Company entered into a noncancelable facility lease agreement (the “Lease”) for 9,836 square feet of research and development and office space in Cambridge, Massachusetts. In March 2020, the Company signed a termination agreement for this lease which was determined to be a lease modification that resulted in a reduction of the right-of-use asset and liability of $2.2 million. The lease termination was effective July 31, 2020 and the Company no longer has any obligations under the Lease.

In accordance with the lease agreement, the Company was required to maintain a security deposit and provided a letter of credit to the landlord for $0.2 million, which was recorded in other assets as of December 31, 2019 and other current assets as of September 30, 2020. In October 2020, the Company was released from the security deposit and letter of credit and collected the $0.2 million previously classified in other current assets.

In April 2019, the Company entered into a facility sublease agreement (the “Sublease”) for 1,471 square feet of office space in Cambridge, Massachusetts. The term of the lease began on June 24, 2019 and terminated on June 30, 2020, and following termination, the Company had no further obligations under the Sublease. The Sublease required the Company to share in prorated operating expenses and property taxes based upon actual amounts incurred; those amounts were considered variable lease costs and, therefore, are not included in the measurement of the lease and are instead recognized to expense as incurred.

In October 2019, the Company entered into a noncancelable facility lease agreement (the “New Lease”) for 34,522 square feet of research and development and office space in Watertown, Massachusetts. The term of the New Lease is 120 months and expires on March 31, 2030. The New 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 New Lease includes a rent escalation clause, and rent expense is being recorded on a straight-line basis. The Company will receive a tenant incentive allowance of $5.5 million in 2020 as the tenant improvements are completed and submitted for reimbursement. 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 other assets as of September 30, 2020.

The Company has received $5.3 million of cash reimbursements from the landlord through September 30, 2020. The tenant improvement receivable in other current assets is $0.2 million at September 30, 2020.

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

The components of the lease costs for the three and nine months ended September 30, 2020 and 2019 were as follows (in thousands):

	Three Months Ended September 30, 2020				Nine Months Ended September 30,
	2020		2019		2020		2019
Operating lease costs	$	606	$	247	$	2,195	$	674
Financing lease costs:
Amortization of right-to-use assets, financing leases		183		80		539		239
Interest expense for financing lease liabilities		29		4		94		16
Variable lease costs		216		103		431		286
Total lease costs	$	1,034	$	434	$	3,259	$	1,215

Supplemental cash flow information relating to the Company’s leases for the nine months ended September 2020 and 2019 was as follows (in thousands):

	Nine Months Ended September 30,
	2020			2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows used in (provided by) operating leases	$	(3,793	)	$	607
Operating cash flows used in finance leases	$	437		$	253
Financing cash flows used in finance leases	$	94		$	16

Weighted average remaining lease terms and discount rates as of September 30, 2020 and December 31, 2019 were as follows:

	September 30,			December 31,
	2020			2019
Remaining lease term:
Operating lease	9.59 Years			9.7 Years
Financing lease	2.99 Years			3.7 Years
Discount Rate:
Operating lease		10.5	%		10.3	%
Financing lease		8.1	%		7.8	%

The undiscounted future lease payments for operating and finance leases as of September 30, 2020, were as follows (in thousands):

Fiscal Year	Operating Leases			Financing Leases
2020 (excluding the nine months ended September 30, 2020)	$	797		$	178
2021		2,691			712
2022		2,581			459
2023		2,659			245
2024		2,732			—
Thereafter		15,739			—
Total minimum lease payments		27,199			1,594
Less amounts representing interest or imputed interest		(10,139	)		(150	)
Present value of lease liabilities	$	17,060		$	1,444