Sesen Bio, Inc. Securities Lawsuit Investigation

Shares drop up to 57% following FDA drug rejection and reports of clinical study violations

On Friday, August 13, Sesen Bio (NASDAQ: SESN) announced that it received a Complete Response Letter (CRL) from the FDA declining to approve an application for its drug candidate, Vicineum. Several days later STAT News reported that the clinical drug trial was marked by thousands of study violations, noncompliance, and signs of toxicity that were not previously disclosed by the company.

Sesen Bio stock plummeted 57% on August 13, 2021, and has continued to drop, causing significant harm to investors.

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Sesen Bio stock drops following FDA rejection and report identifying thousands of violations

On August 13, biotechnology company Sesen Bio announced that it received a negative Complete Response Letter (CRL) from the FDA, determining that it could not approve an application for its leading drug candidate Vicineum, for the treatment of bladder cancer.

Five days later, on August 18, STAT News reported that the Vicineum clinical trial contained more than 2,000 violations, with 215 of those violations classified as “major.” The article also noted that the company may have failed to fully disclose all the potential health risks of the drug, noting that a patient died of liver failure in 2016, and two years later the company claimed at a urology conference that they had not encountered any drug-related deaths. In addition, STAT News reported that multiple doctors acting as investigators in the study had “back-dated” data and engaged in other unethical behavior, potentially putting patients at risk. According to STAT, these allegations were based on hundreds of pages of internal company documents reviewed by STAT reporters.

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