Sesen Bio's bladder cancer candidate shows positive preliminary Phase 3 results
Sesen Bio reported 'positive' preliminary efficacy data for the primary endpoint of its ongoing Phase 3 registration trial, the VISTA Trial, of Vicinium for the treatment of patients with high-grade non-muscle invasive bladder cancer who have been previously treated with bacillus Calmette-Guerin and deemed BCG-unresponsive. The data reported show clinically meaningful complete response rates in evaluable Carcinoma in situ patients at three, six, nine and 12 months of follow-up in the trial consistent with the data in the completed Phase 1 and Phase 2 clinical trials. Vicinium continues to be generally well-tolerated in treated patients. The data reported build upon preliminary three-month data presented from a subset of patients in May 2018 and are for the primary endpoint of the VISTA Trial, which is the complete response rate and duration of response in patients in Cohort. The patient population in Cohort 3 represents an opportunity for future label expansion, and the company plans to report efficacy data from this cohort, as well as the secondary endpoints in the VISTA Trial, in mid-2019. As of the December 3, 2018 data cut off, in patients across all three cohorts, 78% of adverse events were Grade 1 or 2. Complete 12-month efficacy data from all patients in the clinical trial are expected to be reported at a medical meeting in mid-2019.