Leases

12 Months Ended

Dec. 31, 2021

The Company leases office and research and development facilities and equipment under various non-cancellable operating lease agreements.

In January 2010, the Company entered into a lease for office and laboratory space in Malvern, Pennsylvania (the “Malvern Lease”). The Malvern Lease commenced in March 2010 and was amended to extend its term to September 30, 2023, with an option to extend the lease for an additional three years. This lease contains escalating rent payments. In December 2018, the Company entered into a lease for office space in San Diego, California, which expires in October 2022. In June 2020, the Company entered into a lease for additional office space in Malvern, Pennsylvania, which expires in September 2023. As of December 31, 2021, the weighted-average remaining lease term for the Company’s leases was 3.9 years, and the weighted-average discount rate used to determine the right-of-use assets and corresponding operating lease liabilities was 5.9%.

Maturities of operating lease liabilities as of December 31, 2021 are as follows (in thousands):


Year Ending December 31,
2022	$	555
2023	419
2024	279
2025	283
2026	215
Total future minimum lease payments	1,751
Less: Present value adjustment	(202)
Operating lease liabilities	$	1,549

The Company recognizes rent expense for the operating leases on a straight-line basis. Rent expense was $0.7 million and $0.6 million for the years ended December 31, 2021 and 2020, respectively.