Security	Date	Code	Shares	Price	A/D	Owned after	D/I
Common Stock^F1,F2	Mar 19, 2018	C	1,767,676	—	A	1,767,676	D
Common Stock^F1,F2	Mar 19, 2018	C	875,087	—	A	2,642,763	D
Common Stock^F1,F2	Mar 19, 2018	C	427,660	—	A	3,070,423	D
Common Stock^F1,F3	Mar 19, 2018	C	470,427	—	A	470,427	D

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	D/I
Series A Preferred Stock^F2,F1	—	Mar 19, 2018	C	1,767,676	D	—	—	Common Stock	1,767,676	D
Series B Preferred Stock^F2,F1	—	Mar 19, 2018	C	875,087	D	—	—	Common Stock	2,642,763	D
Series C Preferred Stock^F2,F1	—	Mar 19, 2018	C	427,660	D	—	—	Common Stock	3,070,423	D
Series C Preferred Stock^F3,F1	—	Mar 19, 2018	C	470,427	D	—	—	Common Stock	470,427	D

Explanation of responses

F1Immediately prior to the closing of the Issuer's initial public offering of its common stock, each share of Series A, Series B and Series C preferred stock automatically converted into one share of common stock. The Series A, Series B and Series C preferred stock had no expiration date.
F2The securities are directly held by The Column Group II, LP ("TCG II") and indirectly held by The Column Group II GP, LP ("TCG II GP") the general partner of TCG II. TCG II GP has voting and dispositive power with respect to these shares. The individual managing partners of TCG II GP are Peter Svennilson and David Goeddel, who may be deemed to have shared voting, investment and dispositive power with respect to these shares. Each individual managing partner disclaims beneficial ownership of these shares, except to the extent of his pecuniary interest in such shares
F3The securities are directly held by Ponoi Capital, LP ("Ponoi LP") and indirectly held by Ponoi Management, LLC ("Ponoi LLC") the general partner of Ponoi LP. Ponoi LLC has voting and dispositive power with respect to these shares. The individual managing partners of Ponoi LLC are Peter Svennilson, David Goeddel and Tim Kutzkey, who may be deemed to have shared voting, investment and dispositive power with respect to these shares. Each individual managing partner disclaims beneficial ownership of these shares, except to the extent of his pecuniary interest in such shares.