Pfizer has discontinued the development of its B7-H4-directed ADC, B7H4V, resulting in a $1 billion impairment charge

The ADC was acquired through Pfizer’s takeover of Seagen and had been in a phase 1 trial for advanced solid tumors

Enrollment was halted in December 2024, and the program is now permanently discontinued

Pfizer cited clinical data showing that felmetatug vedotin (FV) was unlikely to improve outcomes over standard chemotherapy, though no new safety concerns were observed