11. Leases

Operating Leases

Agreements for Office Space

In November 2017, the Company entered into a sublease agreement with Auxilium Pharmaceuticals, LLC (the “Sublandlord”) pursuant to which it subleases 33,019 square feet of office space for its headquarters in Wayne, Pennsylvania. The sublease has a term that runs through October 2023. If for any reason the lease between Chesterbrook Partners, LP (“the Landlord”) and Sublandlord is terminated or expires prior to October 2023, the Company’s sublease will automatically terminate.

In February 2019, the Company entered into a sublease agreement with a third party for 21,056 square feet of office and laboratory space in St. Louis, Missouri. The lease commenced in June 2019 and has a term that runs through June 2029.

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


		March 31,		December 31,
Operating Leases:	2020		2019
Gross cost	$	5,213	$	5,213
Accumulated amortization		(633)		(480)
Other Assets	$	4,580	$	4,733

Other current liabilities	$	547		526
Other liabilities		3,404		3,548
Total operating lease liabilities	$	3,951	$	4,074

Amortization expense related to operating lease right-of-use assets and liabilities was $257 and $143 for the three months ended March 31, 2020 and 2019, respectively.

Finance Leases

Laboratory Equipment

The Company leases laboratory equipment which is used in its laboratory space in St. Louis, Missouri under two finance lease financing arrangements which the Company entered into in August 2017 and October 2017. The leases have terms which end in October 2020 and December 2020, respectively.