Dosing limit solves BioNTech's clinical hold

The good news for BioNTech is that the US clinical hold on BNT326, the anti-HER3 ADC it licensed from China’s MediLink, lasted barely two months. The big question now is whether the company’s apparent way around this hold – focusing development on doses no greater than 3mg/kg – will leave it with enough of a therapeutic window. So far the signs are good, given that phase 1 results presented at ASCO showed a 42% ORR to hold consistently whether the data were cut by the 24 patients dosed at up to 3mg/kg, or the 29 given higher doses. Investors with a nervous disposition will note that eight of the 11 deepest responses (target lesion decrease of at least 50%) came from doses above 3mg/kg. Still, there didn’t appear to be a meaningful difference between the high and low doses in terms of how soon responding patients relapsed – a positive sign given that at up to 3mg/kg BNT326’s safety profile was described as manageable. And there’s also good news for other developers of HER3-targeting projects: the adverse events, in particular neutropenia and mucositis, were not product-specific but are commonly observed with established chemotherapies, BioNTech told ApexOnco.

MediLink's phase 1 data with BNT326/YL202

Source: ASCO & OncologyPipeline.