Pfizer announced its P-selectin inhibitor inclacumab missed the primary endpoint in the Phase III THRIVE-131 trial for sickle cell disease (SCD), showing no significant reduction in vaso-occlusive crisis rates versus placebo at 48 weeks. The monoclonal antibody (mAb), originally developed by Roche and Genmab before being acquired by Pfizer through its USD 5.4 billion purchase of Global Blood Therapeutics (GBT), demonstrated safety but lacked efficacy in 241 patients aged 16+ receiving 30mg/kg doses every 12 weeks.

The setback follows Pfizer's 2024 withdrawal of Oxbryta (voxelotor) over benefit-risk concerns and the FDA's partial clinical hold on osivelotor, leaving the company without late-stage SCD assets. Inclacumab's failure highlights ongoing challenges in developing non-curative therapies for this inherited blood disorder affecting millions globally.

According to PharmCube's NextBiopharm® database, Pfizer was competing with a number of SCD mAb developers, including a few MNCs. Click here to request a free trial for NextBiopharm®.