Japan-based pharmaceutical firm Eisai Co. has agreed to end its global strategic collaboration with Bristol Myers Squibb (BMS) for the co-development and co-commercialisation of farletuzumab ecteribulin (FZEC), formerly known as MORAb-202, a folate receptor alpha (FRα)-targeting antibody drug conjugate (ADC) due to ongoing portfolio prioritisation efforts within Bristol Myers Squibb.

Based on the agreement, Eisai now owns all rights to FZEC and will solely conduct the global development and commercialization of the agent.

Eisai will accelerate the development of the agent as a high priority with the hope to deliver it to patients as early as possible. Eisai plans to refund a part of the unused portion of the $200 million payment it received towards research and development expenses from Bristol Myers Squibb under the collaboration agreement and record the remaining as other income.

FZEC is Eisai’s first ADC and is composed of Eisai’s in-house developed farletuzumab, a humanised IgG1 monoclonal antibody that binds to the FRα, and Eisai’s in-house developed anticancer agent eribulin, using an enzymatically cleavable linker. Currently, three clinical studies are ongoing: Eisai’s Phase 1/2 study for solid tumors (NCT04300556), and Bristol Myers Squibb’s Phase 2 studies for ovarian, peritoneal and fallopian tube cancers (NCT05613088) and non-small cell lung cancer (NCT05577715).