Following an FDA rejection last year, Sesen Bio announced this morning that it will be pausing development on its lead bladder cancer drug.
With the pause, Sesen can save money while it looks for alternatives, the Cambridge, MA-based biotech said in a press release. It noted that it would be looking for a partner for its bladder cancer drug Vicineum.
In August, the FDA rejected Vicineum — which the biotech ascribed to manufacturing issues and the FDA asking for more data. The biotech said its decision for pausing development came after assessing costs for an additional Phase III trial for the drug in bladder cancer.
In a statement, Sesen Bio CEO and president Thomas Cannell noted that the biotech has had four meetings with the FDA since the rejection. He added:
We have also recently observed an evolution of the current treatment paradigm in NMIBC, with substantial uptake of intravesical chemotherapy (monotherapy and combination therapy) during the ongoing BCG shortage. In assessing the impact of the regulatory and commercial landscape, we have made the decision to pause the clinical development of Vicineum.
In a separate SEC filing, the biotech also said that it is selling its line of IL-6 antibodies to Roche, which it originally out-licensed to the Swiss Pharma in 2016, when it was still known as Eleven Bio. In the original deal, the biotech had licensed the antibodies, including one known as EBI-031 for which the FDA had cleared for clinical trials, for an upfront fee of $7.5 million.
In the new deal, Sesen will be completely offloading EBI-031 and its cohort of IL-6 antibodies to Roche for $40 million upfront, along with a potential $30 million if Roche starts a Phase III trial with EBI-031 before the end of 2026. To that end, despite getting an IND back in 2016, EBI-031 has not seen any clinical trial action — it was listed on clinicaltrials.gov for a Phase I trial in diabetic edema in 2016, only for that trial to get withdrawn a few months later.
Sesen’s stock $SESN dropped around 30% this morning to around $0.60, though it had never really recovered from the precipitous falloff it saw when the FDA doled out its Vicineum rejection.