Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F2,F5	Jul 20, 2018	C	2,560,613	—	A	2,560,613	I	See Footnote
Common Stock^F1,F3,F5	Jul 20, 2018	C	353,590	—	A	353,590	I	See Footnote
Common Stock^F1,F2,F5	Jul 20, 2018	C	413,040	—	A	2,973,653	I	See Footnote
Common Stock^F1,F3,F5	Jul 20, 2018	C	57,035	—	A	410,625	I	See Footnote
Common Stock^F2,F5	Jul 20, 2018	P	51,686	$17.00	A	3,025,339	I	See Footnote
Common Stock^F3,F5	Jul 20, 2018	P	7,137	$17.00	A	417,762	I	See Footnote
Common Stock^F4,F6	Jul 20, 2018	P	141,177	$17.00	A	141,177	I	See Footnote
Common Stock^F7,F4,F6	Jul 20, 2018	P	153,180	$20.73	A	294,357	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 Preferred Stock^F1,F2,F5	—	Jul 20, 2018	C	8,424,416	D	—	—	Common Stock	2,560,613	I
Series A Preferred Stock^F1,F3,F5	—	Jul 20, 2018	C	1,163,311	D	—	—	Common Stock	353,590	I
Series B Preferred Stock^F1,F2,F5	—	Jul 20, 2018	C	1,358,903	D	—	—	Common Stock	413,040	I
Series B Preferred Stock^F1,F3,F5	—	Jul 20, 2018	C	187,648	D	—	—	Common Stock	57,035	I

Explanation of responses

F1The shares of the Issuer's Series A Preferred Stock and Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock, for no additional consideration, at a ratio of 3.29 to 1 share, immediately prior to the consummation of the Issuer's initial public offering. The Series A Preferred Stock and Series B Preferred Stock had no expiration date.
F2These securities are held of record by Vivo Capital Fund VIII, L.P. ("VCF").
F3These securities are held of record by Vivo Capital Surplus Fund VIII, L.P. ("VCSF").
F4These securities are held of record by Vivo Opportunity Fund, L.P. ("VOF").
F5Vivo Capital VIII, LLC ("Vivo LLC") is the general partner of VCF and VCSF. Vivo Capital LLC is the management company of Vivo LLC. The voting members of each of Vivo Capital LLC and Vivo LLC are Frank Kung, Albert Cha, Edgar Engleman, Chen Yu and Shan Fu, none of whom has individual voting or investment power with respect to these securities. Jack B. Nielsen, M.Sc., a director of the Issuer, is a Managing Director at Vivo Capital LLC. Each of the above-listed individuals disclaims beneficial ownership of such shares, except to the extent of its pecuniary interest therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for the purposes of Section 16 or for any other purposes.
F6Vivo Opportunity, LLC is the general partner of VOF. Vivo Capital LLC is the management company of Vivo Opportunity, LLC. The voting members of Vivo Opportunity, LLC are Frank Kung, Albert Cha, Shan Fu, Gaurav Aggarwal and Michael Chang, none of whom has individual voting or investment power with respect to these securities. Each of the above-listed individuals disclaims beneficial ownership of such shares, except to the extent of its pecuniary interest therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for the purposes of Section 16 or for any other purposes.
F7The price reported herein is a weighted average price. These shares were sold in multiple transactions at prices ranging from $19.25 to $24.5, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (7) to this Form 4.