Bronstein, Gewirtz & Grossman, LLC notifies investors that a class action lawsuit has been filed against Sesen Bio, Inc. ("Sesen Bio" or the "Company") (NASDAQ: SESN) and certain of its officers, on behalf of shareholders who purchased or otherwise acquired Sesen Bio securities between December 21, 2020 and August 17, 2021, inclusive (the “Class Period”). Such investors are encouraged to join this case by visiting the firm’s site: www.bgandg.com/sesn.

This class action seeks to recover damages against Defendants for alleged violations of the federal securities laws under the Securities Exchange Act of 1934.

The complaint alleges that throughout the Class Period, Defendants made false and/or misleading statements and/or failed to disclose: (1) that Sesen Bio’s clinical trial for Vicineum had more than 2,000 violations of trial protocol, including 215 classified as "major"; (2) that three of Sesen Bio’s clinical investigators were found guilty of "serious noncompliance," including "back-dating data"; (3) that Sesen Bio had submitted the tainted data in connection with the BLA for Vicineum; (4) that Sesen Bio’s clinical trials showed that Vicineum leaked out into the body, leading to side effects including liver failure and liver toxicity, and increasing the risks for fatal, drug-induced liver injury; (5) that, as a result of the foregoing, the Company’s BLA for Vicineum was not likely to be approved; (6) that, as a result of the foregoing, there was a reasonable likelihood that Sesen Bio would be required to conduct additional trials to support the efficacy and safety of Vicineum; and (7) that, as a result of the foregoing, Defendants’ positive statements about the Company’s business, operations, and prospects were materially misleading and/or lacked a reasonable basis.

A class action lawsuit has already been filed. If you wish to review a copy of the Complaint you can visit the firm’s site: www.bgandg.com/sesn or you may contact Peretz Bronstein, Esq. or his Investor Relations Analyst, Yael Nathanson of Bronstein, Gewirtz & Grossman, LLC at 212-697-6484. If you suffered a loss in Sesen Bio you have until October 18, 2021 to request that the Court appoint you as lead plaintiff. Your ability to share in any recovery doesn't require that you serve as a lead plaintiff.

Bronstein, Gewirtz & Grossman, LLC is a corporate litigation boutique. Our primary expertise is the aggressive pursuit of litigation claims on behalf of our clients. In addition to representing institutions and other investor plaintiffs in class action security litigation, the firm’s expertise includes general corporate and commercial litigation, as well as securities arbitration. Attorney advertising. Prior results do not guarantee similar outcomes.

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