Xynomic Pharma to pay over $500 million for rights to novel RAF inhibitor

US clinical-stage cancer drug developer Xynomic Pharma has acquired exclusive global rights to develop, manufacture and commercialize BI 882370, a second-generation RAF inhibitor, from family-owned German pharma major Boehringer Ingelheim.

Under the terms of the agreement Xynomic will pay Boehringer upfront, milestone and royalty payments up to approximately $502 million.

BI 882370 is a potent and selective RAF inhibitor uniquely binding to the DFG-out conformation, whereas marketed BRAF inhibitors occupy the DFG-in conformation.  BI 882370 inhibited proliferation of BRAFmut melanoma cell lines with 100x higher potency (EC50 1 – 10 nM) than vemurafenib (VEM), a marketed BRAF inhibitor.