JOINT FILING AGREEMENT

EXHIBIT 99.1

JOINT FILING AGREEMENT

The undersigned hereby agree that the Statement on Schedule 13G filed herewith (and any amendments thereto), relating to the Shares of 2seventy bio, Inc., a Massachusetts corporation, is being filed jointly with the Securities and Exchange Commission pursuant to Rule 13d-1(c) under the Securities Exchange Act of 1934, as amended, on behalf of each of the undersigned.

This Agreement may be executed in counterparts and each of such counterparts taken together shall constitute one and the same instrument.

Dated May 1, 2023.

CITADEL SECURITIES LLC			CITADEL ADVISORS LLC
By:	/s/ Xxx Xxxxxx		By:	/s/ Xxxx Xxxxxxxx
	Xxx Xxxxxx, Authorized Signatory			Xxxx Xxxxxxxx, Authorized Signatory
CITADEL SECURITIES GROUP LP			CITADEL ADVISORS HOLDINGS LP
By:	/s/ Xxx Xxxxxx		By:	/s/ Xxxx Xxxxxxxx
	Xxx Xxxxxx, Authorized Signatory			Xxxx Xxxxxxxx, Authorized Signatory
CITADEL SECURITIES GP LLC			CITADEL GP LLC
By:	/s/ Xxx Xxxxxx		By:	/s/ Xxxx Xxxxxxxx
	Xxx Xxxxxx, Authorized Signatory			Xxxx Xxxxxxxx, Authorized Signatory
			XXXXXXX XXXXXXX
			By:	/s/ Xxxx Xxxxxxxx
				Xxxx Xxxxxxxx, attorney-in-fact*

* Xxxx Xxxxxxxx is signing on behalf of Xxxxxxx Xxxxxxx as attorney-in-fact pursuant to a power of attorney previously filed with the Securities and Exchange Commission, and hereby incorporated by reference herein. The power of attorney was filed as an attachment to a filing by Citadel Advisors LLC on Schedule 13G for Zentalis Pharmaceuticals Inc. on April 9, 2020.