The 2022 Annual Meeting of Stockholders of 2seventy bio, Inc. will take place on June 8, 2022 at 8:30am EDT. Given the continuing COVID-19 pandemic, we have determined that the Annual Meeting will be held in a virtual meeting format only via the Internet, with no physical in-person meeting.

Attend and participate in the Annual Meeting online at www.virtualshareholdermeeting.com/TSVT2022. Enter the control number found on your proxy card.

Annual Meeting Materials