X0306 4 2021-06-22 0 0001662244 Cyteir Therapeutics, Inc. CYT 0001867968 Droia Invest II SCSp 28 BOULEVARD JOSEPH II LUXEMBOURG N4 L-1840 LUXEMBOURG 0 0 1 0 0001867904 Wepaven BV BRUSSELSESTEENWEG 11 MEISE C9 1860 BELGIUM 0 0 1 0 0001867855 DF II GP Sarl 28 BOULEVARD JOSEPH II LUXEMBOURG N4 L-1840 LUXEMBOURG 0 0 1 0 0001868013 IHL SA 28 BOULEVARD JOSEPH II LUXEMBOURG N4 L-1840 LUXEMBOURG 0 0 1 0 0001867886 Verelst Luc 28 BOULEVARD JOSEPH II LUXEMBOURG N4 L-1840 LUXEMBOURG 0 0 1 0 0001864377 Naesens Janwillem 128 SPRING ST, BUILDING A, SUITE 510 LEXINGTON MA 02421 0 0 1 0 Common Stock 2021-06-22 4 C 0 3259026 A 3259026 D Common Stock 2021-06-22 4 P 0 277777 18.00 A 3536803 D Series B Convertible Preferred Stock 2021-06-22 4 C 0 10000000 D Common Stock 2933583 0 D Series C Convertible Preferred Stock 2021-06-22 4 C 0 1109368 D Common Stock 325443 0 D Each share of Series B Convertible Preferred Stock and Series C Convertible Preferred Stock converted into shares of Common Stock at a ratio of 3.4088:1 upon completion of the Issuer's initial public offering. The shares have no expiration date. Shares held by Droia Invest II SCSp. DF II GP Sarl is the general partner of Droia Invest II SCSp. Wepaven BV (represented by Janwillem Naesens) and IHL SA (represented by Luc Verelst), the managers of DF II GP Sarl, share voting and investment power with respect to the shares held of record by Droia Invest II SCSp. Mr. Naesens, a member of the Issuer's board of directors, disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein. Luc Verelst disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein. Droia Invest II SCSp, By: DF II GP Sarl, By: /s/ Janwillem Naesens, Name: Wepaven BV (represented by Janwillem Naesens), Title: Manager 2021-06-24 DF II GP Sarl, By: /s/ Janwillem Naesens, Name: Wepaven BV (represented by Janwillem Naesens), Title: Manager 2021-06-24 Wepaven BV, By: /s/ Janwillem Naesens, Name: Janwillem Naesens, Title: Director 2021-06-24 IHL SA, By: /s/ Luc Verelst, Name: Luc Verelst, Title: Director 2021-06-24 Luc Verelst, By: /s/ Luc Verelst 2021-06-24 Janwillem Naesens, By: /s/ Janwillem Naesens 2021-06-24