ESMO 2023 – BioNTech still has work to do on Claudin6

On the face of it a 59% response rate with BioNTech’s Claudin6-targeting Car-T therapy BNT211 seems promising. But a closer look at the results presented at ESMO yesterday, from a phase 1/2 trial in Claudin6-positive solid tumours, shows that this was achieved with a dose of 1x10⁸ Car-T cells that “seems to be toxic”, according to the discussant, Centre Léon Bérard’s Dr Philippe Cassier. 15 of 27 patients receiving this dose experienced cytokine release syndrome. Across the whole trial, the ORR was 45% among 38 evaluable patients – still a respectable result in a study population dominated by ovarian and germ cell cancers. The investigators are now “backfilling” doses to find a recommended phase 2 dose. After last year’s ESMO update covered a manual manufacturing process yesterday's data involved automation, which adds potency and toxicity alike. Some patients also received a mRNA vaccine, called CarVac, designed to boost BNT211. The ESMO presentation didn’t break out responses according to who had received CarVac, although biomarker data suggested that the vaccine could improve BNT211’s persistence. BioNTech still has much to iron out ahead of its phase 2 trial of BNT211, set to begin next year. Still, the company is ahead in the Claudin6 arena.

Source: Dr John Haanen & ESMO.

The Claudin6-targeting pipeline

Source: OncologyPipeline.