Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	D/I
Series D Preferred Stock^F2,F1	—	Jul 5, 2017	C	5,934,050	D	—	—	Common Stock	597,167	D
Series E-2 Preferred Stock^F2,F1	—	Jul 5, 2017	C	1,329,993	D	—	—	Common Stock	133,842	D
Series E-3 Preferred Stock^F2,F1	—	Jul 5, 2017	C	1,153,606	D	—	—	Common Stock	116,091	D
Series F Preferred Stock^F2,F1	—	Jul 5, 2017	C	1,083,119	D	—	—	Common Stock	108,998	D

Explanation of responses

F1The Series D, Series E-2, Series E-3 and Series F Preferred Stock converted into Common Stock on a 9.937-for-one basis upon the closing of the Issuer's initial public offering without payment of consideration. The Series D, Series E-2, Series E-3 and Series F Preferred Stock were convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial pubic offering. The shares had no expiration date.
F2Excel Medical Ventures, LLC is the general partner of Excel Medical Fund, L.P. Steven R. Gullans, Frederick R. Blume and Juan Enriquez are the Managing Directors of Excel Medical Ventures, LLC. Excel Medical Ventures, LLC and each of these individuals may be deemed to share voting and dispositive power with respect to all shares held by Excel Medical Fund, L.P. Each of the filing persons disclaims beneficial ownership of the shares except to the extent of any pecuniary interest therein.