The Company leased office and laboratory space at 215 First Street in Cambridge, Massachusetts (“First Lease”) under an operating lease, which commenced in November 2015 and was originally set to expire in December 2020. As discussed below, the Company executed a lease at 399 Binney Street (“Binney Lease”) whereby the Company vacated the 215 First Street lease in January 2019 and the future lease commitments terminated at no cost once the Binney Lease commenced. The lease included certain tenant improvement allowances, which the Company amortized through January 2019, the termination of the lease.

In December 2017, the Company entered into a facility lease agreement for approximately 44,336 square feet of office and laboratory space at 399 Binney Street, Cambridge, Massachusetts, which was increased to 44,807 square feet in January 2018. The Company gained control of the leased space in January 2019 and recorded a right of use asset and a lease liability, accordingly. The lease expires in April 2029, subject to certain renewal options, which have not been included in the Company’s right of use asset and liability, as the Company is not reasonably certain to exercise those options.

In September 2020, the Company entered into an amendment to its facility lease agreement to expand the leased area by approximately 1,824 square feet of office space at 399 Binney Street, Cambridge, Massachusetts. The amended lease expires in April 2029, subject to certain renewal options. The amendment to the lease agreement met the criteria to be accounted for as a separate lease. The Company gained control of the leased space in October 2020 and recorded a right of use asset and a lease liability, accordingly. The right of use asset and lease liability recorded in connection with this amendment were not material.

As discussed in Note 2, the Company provided a letter of credit in the amount of $878 with a financial institution, which expires September 30, 2028.

The following table summarizes the presentation of the Company’s operating leases on its consolidated balance sheets:

		December 31,		December 31,
	Balance sheet location	2020		2019
Assets:
Operating lease assets	Operating lease assets	$	22,579	$	23,560
Liabilities:
Current operating lease liabilities	Operating lease liabilities	$	1,521	$	1,249
Non-current operating lease liabilities	Operating lease liabilities, net of current portion		22,901		23,583
	Total lease liabilities	$	24,422	$	24,832

The following table summarizes the effect of lease costs in the Company’s consolidated statements of operations and comprehensive loss for the years ended December 31, 2020 and 2019:

	Statement of operations location	Year Ended December 31, 2020		Year Ended December 31, 2019
Operating lease costs	Research and development	$	3,273	$	3,216
	General and administrative	748			581
	Total operating lease cost	$	4,021	$	3,797

The Company made cash payments of $4,878 and $2,602 under the lease agreements during the years ended December 31, 2020 and 2019, respectively.

The minimum lease payments as of December 31, 2020 for the next five years and thereafter is expected to be as follows:

Year Ending December 31,	Amount
2021	$	3,985
2022		4,134
2023		4,254
2024		4,377
2025		4,503
Thereafter		15,959
Total lease payments		37,212
Less: interest		(12,790	)
Present value of operating lease liabilities	$	24,422

The weighted average remaining lease term and weighted average discount rate of the operating leases were 8.3 years and 10.4%, respectively, at December 31, 2020. The weighted average remaining lease term and weighted average discount rate of the operating leases were 9.3 years and 10.4%, respectively, at December 31, 2019.