Eisai announced today that it's ADC collaboration with Bristol Myers Squibb for the co-development and co-commercialization of farletuzumab ecteribulin (FZEC), an antibody-drug conjugate targeting the folate receptor alpha (FRα), has come to an end.
The collaboration was inked back in 2021, with BMS handing Eisai $650 million upfront. Eisai was eligible for up to $2.45 billion in milestone payments. The pair had planned to jointly develop and market the ADC in Asia, Europe, the U.S. and Canada.
Going forward, Eisai will regain all rights to FZEC and will independently manage its global development and commercialization. For BMS, the decision aligns with the company's ongoing portfolio prioritization efforts, announced earlier this year.
Eisai has committed to accelerating the development of FZEC, and as part of the agreement to end the collab with BMS, the drugmaker plans to refund a portion of the unused funds from the $200 million payment received from BMS for R&D expenses.
FZEC, Eisai's first ADC, is composed of the company's in-house developed farletuzumab — a humanized IgG1 monoclonal antibody that targets FRα — and the anticancer agent eribulin, connected via an enzymatically cleavable linker.
Currently, three clinical studies are underway: Eisai's phase 1/2 study for solid tumors (NCT04300556) and BMS' phase 2 studies for ovarian, peritoneal and fallopian tube cancers (NCT05613088) and non-small cell lung cancer (NCT05577715).