Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F2,F3	Oct 2, 2017	C	839,110	—	A	839,110	I	See Footnote
Common Stock^F1,F2,F3	Oct 2, 2017	C	1,118,722	—	A	1,957,832	I	See Footnote
Common Stock^F1,F4,F5	Oct 2, 2017	C	279,703	—	A	279,703	I	See Footnote
Common Stock^F1,F4,F5	Oct 2, 2017	C	1,118,722	—	A	1,398,425	I	See Footnote
Common Stock^F1,F4,F5	Oct 2, 2017	C	372,883	—	A	1,771,308	I	See Footnote
Common Stock^F4,F5	Oct 2, 2017	P	375,000	$17.00	A	2,146,308	I	See Footnote

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	D/I
Series B-1 Preferred Stock^F2,F3,F1	—	Oct 2, 2017	C	148,515	D	—	—	Common Stock	839,110	I
Series B-2 Preferred Stock^F2,F3,F1	—	Oct 2, 2017	C	198,004	D	—	—	Common Stock	1,118,722	I
Series B-1 Preferred Stock^F4,F5,F1	—	Oct 2, 2017	C	49,505	D	—	—	Common Stock	279,703	I
Series B-2 Preferred Stock^F4,F5,F1	—	Oct 2, 2017	C	198,004	D	—	—	Common Stock	1,118,722	I
Series C Preferred Stock^F4,F5,F1	—	Oct 2, 2017	C	65,997	D	—	—	Common Stock	372,883	I

Explanation of responses

F1Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into 5.65 shares of common stock of the Issuer.
F2The reportable securities are owned directly by New Leaf Ventures III, L.P. ("NLV III"). New Leaf Venture Associates III, L.P. ("NLV Associates III") is the sole general partner of NLV III. New Leaf Venture Management III, L.L.C. ("NLV Management III") is the sole general partner of NLV Associates III. New Leaf Venture Partners, L.L.C. ("NLVP") is the investment adviser of NLV III. Each of NLV Associates III and NLV Management III disclaim beneficial ownership of these securities and this report shall not be deemed an admission that NLV Associates III or NLV Management III are beneficial owners of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein.
F3(Continuation from footnote 2) Each of Liam Ratcliffe, a member of the Issuer's board of directors, Jeani Delagardelle, Ronald M. Hunt and Vijay K. Lathi (each, a "Member" and collectively, the "Members") is a member of NLV Management III and may be deemed to have shared voting and dispositive power of these securities. Each of the Members disclaims beneficial ownership of these securities and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein.
F4The reportable securities are owned directly by New Leaf Biopharma Opportunities I, L.P. ("Biopharma I"). New Leaf BPO Associates I, L.P. ("NLBA I") is the sole general partner of Biopharma I. NLV Management III is the sole general partner of NLBA I. NLVP is the investment adviser of Biopharma I. Each of NLBA I and NLV Management III disclaim beneficial ownership of these securities and this report shall not be deemed an admission that NLBA I or NLV Management III are beneficial owners of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein.
F5(Continuation from footnote 4) Each of the Members may be deemed to have shared voting and dispositive power of these securities. Each of the Members disclaims beneficial ownership of these securities and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein.