Eisai to progress ADC development after BMS collaboration

Eisai announced the conclusion of its collaboration with Bristol Myers Squibb (BMS) regarding the co-development and co-commercialization of farletuzumab ecteribulin (FZEC), an antibody-drug conjugate (ADC) aimed at the folate receptor alpha (FRα). The collaboration, which began in 2021, initially involved BMS providing Eisai with an upfront payment of $650 million. Additionally, Eisai stood to receive up to $2.45 billion in milestone payments. The partnership was designed to jointly develop and market FZEC across Asia, Europe, the United States, and Canada.

With this collaboration ending, Eisai will recover all rights to FZEC and will independently oversee its global development and marketing efforts. For BMS, this decision is in line with the company's strategic portfolio prioritization efforts, which were announced earlier this year. Eisai has expressed its commitment to expediting the development of FZEC. As part of the agreement to terminate the partnership with BMS, Eisai will return a portion of the unused funds from the $200 million received from BMS for research and development expenses.

FZEC is notable as Eisai's first ADC. It consists of farletuzumab, a humanized IgG1 monoclonal antibody targeting the folate receptor alpha, and eribulin, an anticancer agent. These components are linked via an enzymatically cleavable linker. Currently, there are three ongoing clinical studies involving FZEC. Eisai is conducting a phase 1/2 study for solid tumors (NCT04300556). Meanwhile, BMS is running two phase 2 studies, one focusing on ovarian, peritoneal, and fallopian tube cancers (NCT05613088) and the other on non-small cell lung cancer (NCT05577715).

This strategic shift allows Eisai to fully control the future trajectory of FZEC, potentially accelerating its path to market. The decision underlines Eisai's dedication to advancing its oncology portfolio and optimizing the therapeutic potential of its in-house innovations.