Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	D/I
Series C Convertible Preferred Stock^F5,F1,F4	—	Oct 25, 2016	C	610,136	D	—	—	Common Stock	1,370,887	D
Series D Convertible Preferred Stock^F5,F2,F4	—	Oct 25, 2016	C	190,154	D	—	—	Common Stock	190,154	D
Series E Convertible Preferred Stock^F5,F3,F4	—	Oct 25, 2016	C	155,548	D	—	—	Common Stock	155,548	D
Series D Preferred Stock Warrant (Right to Buy)^F5,F4	$0.001	Oct 25, 2016	C	72,389	D	Nov 1, 2012	Nov 1, 2019	Common Stock	72,389	D

Explanation of responses

F1The Series C Convertible Preferred Stock converted into Common Stock on a 2.24685484-for-1 basis and had no expiration date.
F2The Series D Convertible Preferred Stock converted into Common Stock on a 1-for-1 basis and had no expiration date.
F3The Series E Convertible Preferred Stock converted into Common Stock on a 1-for-1 basis and had no expiration date.
F4Reflects 5.882698 for 1 reverse stock split which became effective on October 5, 2016.
F5Represents shares directly beneficially owned by New Leaf Ventures II, L.P. ("NLV II"). New Leaf Venture Associates II, L.P. ("NLV Associates II") is the general partner of NLV II and New Leaf Venture Management II, L.L.C. ("NLV Management II") is the general partner of NLV Associates II. Philippe O. Chambon, Jeani Delagardelle, Ronald Hunt, Vijay Lathi and Liam Ratcliffe are the individual managers of NLV Management II (the "Individual Managers"). NLV Associates II and NLV Management II disclaim beneficial ownership of such shares, except to the extent of their pecuniary interest therein. Vijay Lathi is a director of the Issuer and, accordingly, files separate Section 16 reports. As one of five individual managers, each of the Individual Managers disclaims beneficial ownership over the shares reported herein, and in all events disclaims pecuniary interest except to the extent of his or her economic interest.