Eisai’s abandoned Enhertu challenger set to live on at BlissBio

CAR-T Digest - August 2020

21 Mar 2025: Eisai’s abandoned Enhertu challenger set to live on at BlissBio

Eisai decided not to exercise its option to acquire BB-1701, a HER2-directed antibody-drug conjugate (ADC) from Bliss Biopharmaceutical, despite initially agreeing to a potential $2 billion deal
Despite Eisai’s withdrawal, BlissBio plans to continue BB-1701’s development independently, keeping the ADC in clinical trials
A Phase 2 trial of BB-1701 showed promise in treating solid tumors, including breast cancer, with Angle’s liquid biopsy technology measuring HER2 status over time
Although not progressing BB-1701, Eisai will remain connected to the project as a licensor for the eribulin payload used in the ADC
Without a global partner, BlissBio must compete in China against companies like Duality Biologics, GeneQuantum Healthcare, and Jiangsu HengRui Medicine, while BioNTech and Johnson & Johnson have invested in rival HER2 ADCs