Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Series B-1 Preferred Stock^{F2,F3,F4,F5,F6,F1}	—	Mar 8, 2016	C	400,422	D	—	—	Common Stock	400,422	0	D
Series C-1 Preferred Stock^{F2,F3,F4,F5,F6,F1}	—	Mar 8, 2016	C	360,640	D	—	—	Common Stock	360,640	0	D

Explanation of responses

F1All outstanding Preferred Stock automatically converted into Common Stock on a one-for-one basis immediately prior to the closing of the Issuer's initial public offering for no additional consideration. The Preferred Stock had no expiration date.
F2The securities reported as directly beneficially owned by the designated Reporting Person may be deemed to be indirectly beneficially owned by each of the Reporting Owners listed below, each of whom is a managing member of One Palmer Square Associates VIII, LLC, the sole general partner of the designated Reporting Person. Pursuant to Instruction 4(b)(iv) of Form 4, each such individual has elected to report as indirectly beneficially owned the entire number of securities owned by the designated Reporting Person, however each of them disclaims beneficial ownership of any securities, and any proceeds thereof, that exceed his or her pecuniary interest therein and/or that are not actually distributed to him or her.
F3As managing members of the sole general partner of DP VIII Associates, L.P., each Reporting Owner listed below may also be deemed to indirectly beneficially own the securities of the Issuer held by DP VIII Associates, L.P., as reported on a Form 4 for DP VIII Associates, L.P. filed on the same date as this Form 4.
F4As managing members of the sole general partner of Domain Partners VI, L.P., each Reporting Owner listed below (except for Brian K. Halak) may also be deemed to indirectly beneficially own the securities of the Issuer held by Domain Partners VI, L.P., as reported on a Form 4 for Domain Partners VI, L.P. filed on the same date as this Form 4.
F5As managing members of the sole general partner of DP VI Associates, L.P., each Reporting Owner listed below (except for Brian K. Halak) may also be deemed to indirectly beneficially own the securities of the Issuer held by DP VI Associates, L.P., as reported on a Form 4 for DP VI Associates, L.P. filed on the same date as this Form 4.
F6As managing members of Domain Associates, LLC, each Reporting Owner listed below may also be deemed to indirectly beneficially own 13,564 shares of Common Stock held by Domain Associates, LLC.