Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2017

Schedule of Future Minimum Lease Payments Under Non-Cancelable Operating Leases

As of June 30, 2017, future minimum lease payments under non-cancelable operating leases are as follows (in thousands):

	Operating
	Leases
2017 (remainder of year)	$	802
2018		1,638
2019		1,687
2020		1,626
2021		665
Thereafter		952
Total minimum lease payments	$	7,370

The Trustees of the University of Pennsylvania [Member]

Summary of Expenses Incurred by Company

Expenses incurred by the Company related to its license from Penn were as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Sublicense fees	$	656	$	225	$	701	$	257
Royalties on sales of reagents		4		7		4		9
Maintenance of licensed patents		85		14		169		43
	$	745	$	246	$	874	$	309

GlaxoSmithKline LLC [Member]

Summary of Expenses Incurred by Company

Expenses incurred by the Company related to its license from GSK were as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Sublicense fees	$	656	$	225	$	701	$	257
Royalties on sales of reagents		2		4		2		6
Maintenance of licensed patents		14		137		159		230
	$	672	$	366	$	862	$	493