Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F2,F3,F4	Feb 3, 2015	C	1,311,597	—	A	1,311,597	I	By ILSF LP1
Common Stock^F1,F2,F3,F4	Feb 3, 2015	C	15,562	—	A	15,562	I	By ILSF Co-Invest
Common Stock^F1,F2,F3,F4	Feb 3, 2015	C	12,529	—	A	12,529	I	By ILSF Strategic
Common Stock^F1,F2,F5,F6	Feb 3, 2015	C	1,781,615	—	A	1,781,615	I	By Fund IV
Common Stock^F5,F6	Feb 3, 2015	P	308,878	$17.00	A	2,090,493	I	By Fund IV
Common Stock^F1,F2,F5,F6	Feb 3, 2015	C	50,581	—	A	50,581	I	By Fund IV Strategic
Common Stock^F5,F6	Feb 3, 2015	P	8,769	$17.00	A	59,350	I	By Fund IV Strategic

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	D/I
Series A Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	1,174,836	D	—	—	Common Stock	293,709	I
Series A Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	13,940	D	—	—	Common Stock	3,485	I
Series A Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	11,224	D	—	—	Common Stock	2,806	I
Series B Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	2,434,052	D	—	—	Common Stock	608,513	I
Series B Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	28,882	D	—	—	Common Stock	7,220	I
Series B Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	23,254	D	—	—	Common Stock	5,813	I
Series C Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	1,213,172	D	—	—	Common Stock	409,375	I
Series C Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	14,395	D	—	—	Common Stock	4,857	I
Series C Convertible Preferred Stock^F1,F2,F3,F4	—	Feb 3, 2015	C	11,590	D	—	—	Common Stock	3,910	I
Series D Convertible Preferred Stock^F1,F2,F5,F6	—	Feb 3, 2015	C	2,977,679	D	—	—	Common Stock	744,419	I
Series D Convertible Preferred Stock^F1,F2,F5,F6	—	Feb 3, 2015	C	84,539	D	—	—	Common Stock	21,134	I
Series E Convertible Preferred Stock^F1,F2,F5,F6	—	Feb 3, 2015	C	4,148,785	D	—	—	Common Stock	1,037,196	I
Series E Convertible Preferred Stock^F1,F2,F5,F6	—	Feb 3, 2015	C	117,788	D	—	—	Common Stock	29,447	I

Explanation of responses

F1Series A, B, C, D and E Convertible Preferred Stock (collectively, the "Preferred Stock") has no expiration date.
F2The Preferred Stock converted into shares (the "Shares") of Issuer common stock upon the closing of the Issuer's initial public offering, giving effect to the 1-for-4 reverse stock split effected by the Issuer on January 12, 2015, which changed the conversion rate for the Series A, B, D and E Convertible Preferred Stock from 1-for-1 to 0.25-for-1 and, for the Series C Convertible Preferred Stock, from 1.3498-for-1 to an approximate 0.3374-for-1 basis (subject to the payment of cash, or the rounding up by a maximum of one share, for any fractional shares, in accordance with the Issuer's certificate of incorporation).
F3International 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.
F4Each 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.
F5SV 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.
F6Each 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.