11. Leases

The Company has operating leases for office space and laboratory facilities, and finance leases for fleet vehicles leased for its sales force and laboratory equipment. The components of lease expense were as follows:


	Six Months Ended
	June 30,
	2019
Operating lease expense	$	302

Finance Leases:
Amortization of right-to-use assets	$	313
Interest expense		67
Total finance lease expenses	$	380

During the three and six months ended June 30, 2018 the Company recorded $201 and $478, respectively, of rent expense which was recognized on a straight-line basis over the term of the lease.

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. Subject to the consent of Chesterbrook Partners, LP (“Landlord”) as set forth in the lease by and between them and Sublandlord, the sublease has a term that runs through October 2023. If for any reason the lease between 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 with total future total rent payments of $3,538. The Company has also agreed to pay $1,472 of the total renovation and improvement costs incurred by the landlord, which is collateralized by a standby letter of credit held by the Company. 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:


		June 30,
Operating Leases:	2019
Gross cost	$	5,207
Accumulated amortization		(177)
Operating lease right-of-use assets	$	5,030

Other current liabilities	$	488
Other liabilities		3,794
Total operating lease liabilities	$	4,282

Finance Leases

Laboratory Equipment

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

Fleet Vehicles

The Company leases automobiles for its sales force and other field-based employees under the terms of a master lease agreement with a third party. The lease term for each automobile begins on the date the Company takes delivery and continues for a period of four years.

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


		June 30,
Finance Leases:	2019
Property and equipment, gross	$	2,557
Accumulated depreciation		(763)
Property and equipment, net	$	1,794

Other current liabilities	$	503
Other liabilities		1,173
Total finance lease liabilities	$	1,676

Supplemental information related to operating and finance leases is as follows:


	Six Months Ended
	June 30,
Supplemental Cash Flow Lease Information:	2019
Operating cash flows from operating leases	$	309
Operating cash flows from finance leases		61
Financing cash flows from finance leases		240

Leased assets obtained in exchange for new operating lease liabilities	$	3,060


Weighted-Average Remaining Lease Term (in years):
Operating leases		7.19
Finance leases		2.74

Weighted-Average Discount Rate:
Operating leases		10.10	%
Finance leases		6.94	%

Future maturities of lease liabilities under operating and finance leases as of June 30, 2019 are as follows:


		Operating		Finance
Year Ending December 31,		Leases		Leases
2019	$	419	$	295
2020		909		567
2021		934		448
2022		959		180
2023		877		—
Thereafter		2,024		—
Total undiscounted lease payments		6,122		1,490
Less: unrecognized interest		(1,840)		(187)
Plus: residual value guarantees		—		373
Total lease liability	$	4,282	$	1,676

The undiscounted lease payments presented in the table above are consistent with the future minimum lease payments disclosed in the Company’s Annual Report on Form 10-K filed with the SEC on March 18, 2019 under the prior lease guidance.