Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F4	May 7, 2018	C	360,902	—	A	360,902	I	See Footnote
Common Stock^F2,F4	May 7, 2018	C	389,893	—	A	750,795	I	See Footnote
Common Stock^F1,F4	May 7, 2018	C	472,581	—	A	1,223,376	I	See Footnote
Common Stock^F1,F4	May 7, 2018	C	210,147	—	A	1,433,523	I	See Footnote
Common Stock^F3,F4	May 7, 2018	C	163,962	—	A	1,597,485	I	See Footnote
Common Stock^F1,F4	May 7, 2018	C	570,769	—	A	2,168,254	I	See Footnote

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^F4,F1	—	May 7, 2018	C	2,400,000	D	—	—	Common Stock	360,902	I
Series B Convertible Preferred Stock^F4,F2	—	May 7, 2018	C	2,102,315	D	—	—	Common Stock	389,893	I
Series C Convertible Preferred Stock^F4,F1	—	May 7, 2018	C	3,142,670	D	—	—	Common Stock	472,581	I
Series D Convertible Preferred Stock^F4,F1	—	May 7, 2018	C	1,397,478	D	—	—	Common Stock	210,147	I
Series E Convertible Preferred Stock^F4,F3	—	May 7, 2018	C	948,855	D	—	—	Common Stock	163,962	I
Series F Convertible Preferred Stock^F4,F1	—	May 7, 2018	C	3,795,620	D	—	—	Common Stock	570,769	I

Explanation of responses

F1Shares of Series A, Series C, Series D and Series F Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock at a 1-for-0.1504 conversion rate immediately prior to the closing of the Issuer's initial public offering ("IPO") for no additional consideration (subject to the payment of cash in lieu of any fractional shares in accordance with the Issuer's Sixth Amended and Restated Certificate of Incorporation (as amended, the "Certificate of Incorporation")). These shares had no expiration date.
F2Shares of Series B Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock at a 1-for-0.1855 conversion rate immediately prior to the closing of the Issuer's IPO for no additional consideration (subject to the payment of cash in lieu of any fractional shares in accordance with the Issuer's Certificate of Incorporation). These shares had no expiration date.
F3Shares of Series E Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock at a 1-for-0.1728 conversion rate immediately prior to the closing of the Issuer's IPO for no additional consideration (subject to the payment of cash in lieu of any fractional shares in accordance with the Issuer's Certificate of Incorporation). These shares had no expiration date.
F4The shares are held of record by U.S. Venture Partners IX, L.P. ("USVP IX"). Presidio Management Group IX, LLC ("PMG IX") is the general partner of USVP IX and may be deemed to have sole voting and dispositive power over the shares held by USVP IX. Casey Tansey, a director of the Issuer, and each of Irwin Federman, Steven M. Krausz, David E. Liddle, Paul A. Matteucci, Jonathan D. Root, and Philip M. Young, are managing members of PMG IX, and may be deemed to share voting and dispositive power over the shares held by USVP IX. Such persons and entities disclaim beneficial ownership of shares held by USVP IX, except to the extent of any proportionate pecuniary interest therein.