Design of a Phase 3, Global, Multicenter, Randomized, Placebo-controlled, Double-blind Study of Nipocalimab in Pregnancies At-risk for Severe Hemolytic Disease of the Fetus and Newborn

Nipocalimab is a neonatal fragment crystallizable (Fc) receptor (FcRn)-blocking monoclonal antibody that inhibits placental immunoglobulin G (IgG) transfer and lowers circulating maternal IgG levels. In an open-label, single-arm, phase 2 study, nipocalimab demonstrated evidence of safety and efficacy that support further investigation in a pivotal phase 3 trial of recurrent hemolytic disease of the fetus and newborn (HDFN). The phase 3 AZALEA study aims to evaluate the efficacy and safety of nipocalimab in a larger population at risk for severe HDFN, defined as HDFN associated with poor fetal outcomes or neonatal death.