MPM BIOVENTURES 2018, L.P. sold TRDA

Footnotes

The shares were sold as follows: 13,208 by MPM BioVentures 2014, L.P. ("BV 2014"), 881 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 455 by MPM Asset Management Investors BV2014 LLC ("AM BV2014"), 13,556 by MPM BioVentures 2018, L.P. ("BV 2018"), 720 by MPM BioVentures 2018 (B), L.P. ("BV 2018(B)") and 268 by MPM Asset Management Investors BV2018 LLC ("AM BV2018"). MPM BioVentures 2014 GP LLC and MPM BioVentures 2014 LLC ("BV2014 LLC") are the direct and indirect general partners of BV 2014 and BV 2014(B). BV2014 LLC is the manager of AM BV2014. MPM BioVentures 2018 GP LLC and MPM BioVentures 2018 LLC ("BV2018 LLC") are the direct and indirect general partners of BV 2018 and BV 2018(B). BV 2018 LLC is the manager of AM BV2018. Messrs. Evnin, Foley and Gadicke are managing directors of BV 2014 LLC and BV 2018 LLC.; Price represents the weighted average sale price of the shares sold. The sale price ranged from $6.80 to $7.15 per share. Upon request by the Commission staff, the Issuer, or a security holder of the Issuer, the Reporting Person will provide full information regarding the number of shares sold at each separate price within the range set forth in this Form 4.; The shares are held as follows: 1,908,217 by BV 2014, 127,274 by BV 2014(B), 65,681 by AM BV2014, 1,958,433 by BV 2018, 104,089 by BV 2018(B) and 38,652 by AM BV2018.; Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.