Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock, $0.001 par value^F1,F2,F3	Jan 31, 2017	S	220,431	$17.00	D	1,091,166	I	By ILSF LP1
Common Stock, $0.001 par value^F1,F2,F3	Jan 31, 2017	S	2,615	$17.00	D	12,947	I	By ILSF Co-Invest
Common Stock, $0.001 par value^F1,F2,F3	Jan 31, 2017	S	2,106	$17.00	D	10,424	I	By ILSF Strategic
Common Stock, $0.001 par value^F1,F4,F5	Jan 31, 2017	S	299,424	$17.00	D	1,791,070	I	By Fund IV
Common Stock, $0.001 par value^F1,F4,F5	Jan 31, 2017	S	8,501	$17.00	D	50,849	I	By Fund IV Strategic

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

F1Represents a public offering price of $17.00 per share before underwriting discounts and commissions pursuant to an Underwriting Agreement dated January 25, 2017, which offering closed on January 31, 2017.
F2International Life Sciences Fund III (GP), L.P. ("Fund III GP") is the general partner of each of: (i) International Life Sciences Fund III (LP1), L.P. ("ILSF LP1"), (ii) International Life Sciences Fund III Co-Investment, L.P. ("ILSF Co-Invest") and (iii) International Life Sciences Fund III Strategic Partners, L.P. ("ILSF Strategic" and collectively, the "Fund III Entities"). ILSF III, LLC (the "ILSF General Partner") is the general partner of Fund III GP and, through an investment committee comprised of James Garvey, Kate Bingham, Eugene D. Hill, III and Michael Ross controls voting and investment decisions over the Issuer's shares held by the Fund III Entities by majority vote.
F3Each member of the investment committee of ILSF General Partner disclaims beneficial ownership over the Shares held by the Fund III Entities except to the extent of any pecuniary interest therein. Each of ILSF General Partner and Fund III GP disclaim beneficial ownership over the Shares held by the Fund III Entities except to the extent of their respective pecuniary interest therein.
F4SV Life Sciences Fund IV (GP), L.P. ("Fund IV GP") is the general partner of each of SV Life Sciences Fund IV, L.P. ("Fund IV") and SV Life Sciences Fund IV Strategic Partners, L.P. ("Fund IV Strategic" and together with Fund IV, the "Fund IV Entities"). SVLSF IV, LLC (the "SVLS General Partner") is the general partner of Fund IV GP and, through an investment committee comprised of David Milne (also a member of the Issuer's board of directors), James Garvey, Kate Bingham, Eugene D. Hill, III and Michael Ross controls voting and investment decisions over the Issuer's shares held by the Fund IV Entities by a majority vote.
F5Each member of the investment committee of SVLS General Partner disclaims beneficial ownership over the Shares held by the Fund IV Entities except to the extent of any pecuniary interest therein. Each of SVLS General Partner and Fund IV GP disclaim beneficial ownership over the Shares held by the Fund IV Entities except to the extent of their respective pecuniary interest therein.