According to the Complaint, Sesen Bio, Inc. is a late-stage clinical company that purports to advance targeted fusion protein (“TFP”) therapeutics for cancer treatments. Its most advanced product candidate is Vicineum (VB4-845), a locally administered TFP developed as a treatment of bacillus CalmetteGuérin (“BCG”)-unresponsive non-muscle invasive bladder cancer (“NMIBC”). Sensen Bio reported preliminary efficacy data from its ongoing Phase 3 clinical trial for Vicineum, the VISTA trial, in August 2019. On December 21, 2020, the Company announced that it had submitted its Biologics License Application (“BLA”) to the U.S. Food and Drug Administration (“FDA”) for Vicineum for the treatment of BCG-unresponsive NMIBC.

The Complaint alleges that throughout the Class Period, Defendants made materially false and/or misleading statements, as well as failed to disclose material adverse facts about the Company’s business, operations, and prospects. Specifically, the Complaint alleges Defendants failed to disclose to investors: (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.

On October 29, 2021, the Court issued an Order consolidating cases and appointing Lead Plaintiffs and Counsel. All future docketing was ordered to be done in the lead case 21-CV-07025.

Lead Plaintiffs filed an amended Complaint on December 6, 2021. Defendants filed a Motion to Dismiss the amended Complaint on March 7, 2022.

On July 27, 2022, the parties notified the Court that they had reached an agreement in principle to settle the case. The parties entered into a Stipulation and Agreement of Settlement on August 3.

On August 31, 2022, the Court issued an Order denying without prejudice Defendants' Motion to Dismiss the amended Complaint, as the parties had reached a Settlement. On October 3, the Court granted preliminary approval of the Settlement. On January 31, 2023, the Court granted final approval of the Settlement and entered Final Judgment.

On October 26, 2023, the Court issued an Order approving distribution of the Settlement fund.