Leases

12 Months Ended

Dec. 31, 2021

The Company currently has operating leases for office and research laboratory space, equipment, and vehicles under agreements expiring at various dates through 2044, which include renewal options on leases which the Company is reasonably certain to exercise.

For the years ended December 31, 2021, and 2020, operating lease expense was $10.0 million and $11.1 million and variable lease expense was $2.1 million and $1.8 million, respectively. For the years ended December 31, 2021, and 2020, the Company paid $8.4 million and $9.6 million, respectively, for amounts included in the measurement of operating lease liabilities and recorded $0.3 million and $1.7 million, respectively, of right-of-use assets and $0.3 million and $0.5 million, respectively, of tenant improvements paid through lease incentives in exchange for new operating lease liabilities.

Commitments under finance leases are not significant for the year ended December 31, 2021.

Supplemental balance sheet information related to operating leases were as follows:


(in thousands, except year and discount rate amounts)	December 31, 2021			December 31, 2020
Operating lease ROU assets, net	$	20,586		$	23,296

Current portion of the operating lease liabilities	$	7,409		$	6,872
Non-current portion of the operating lease liabilities	43,363			45,604
Total operating lease liability	$	50,772		$	52,476

Weighted-average remaining lease terms (years)	19.6			19.8
Weighted-average discount rate	13.1		%	13.0		%

At December 31, 2021, the future minimum operating lease payments were as follows:


(in thousands)	Operating Lease
2022	$	8,514
2023	8,622
2024	8,347
2025	8,304
2026	8,454
Thereafter	145,948
Total lease payments	188,189
Less lease incentives	(28,939)
Less imputed interest	(108,478)
Total operating lease liability	$	50,772

As of December 31, 2021, the Company has an additional operating lease for office space that has not yet commenced, with minimum lease payments of $15.1 million. This operating lease commenced during the first quarter of 2022 with a lease term of ten years.