A Study of Nipocalimab in Reducing the Risk of Fetal and Neonatal Alloimmune Thrombocytopenia (FNAIT)

Double-blind, Randomized, Placebo-controlled Study Evaluating the Safety and Efficacy of Nipocalimab in Reducing the Risk of Fetal and Neonatal Alloimmune Thrombocytopenia (FNAIT) in At-risk Pregnancies

The purpose of this study is to evaluate the effectiveness of nipocalimab compared with placebo in reducing the risk of severe fetal and neonatal alloimmune thrombocytopenia (FNAIT).

Inclusion Criteria:

• Pregnant and an estimated gestational age (GA; based on ultrasound dating) from Week 13 to 18 at randomization
• Has a history of greater than or equal to (>=) 1 prior pregnancy with fetal and neonatal alloimmune thrombocytopenia (FNAIT) (including neonatal platelet count less than (<) 150×10^9/Liter) with none of them affected by fetal/neonatal intracranial hemorrhage (ICH) or severe hemorrhage based on a clinical review of the medical records
• Current pregnancy with presence of maternal anti- human platelet antigen (HPA)-1a alloantibody and positive fetal HPA-1a genotype as confirmed by cell-free fetal deoxyribonucleic acid (DNA) in maternal blood
• Health status considered stable by the investigator based on physical examination, medical history, vital signs, 12-lead Electrocardiogram (ECG), and clinical laboratory tests performed at screening
• For maternal participant and neonate/infant, willing to forego participation in another clinical study of an investigational therapy until the last follow-up visit

Exclusion Criteria:

• Currently pregnant with multiple gestations (twins or more)
• History of severe preeclampsia in a previous pregnancy
• History of myocardial infarction, unstable ischemic heart disease, or stroke
• Known allergies, hypersensitivity, or intolerance to nipocalimab or its excipients (refer to the Investigator Brochure (IB))
• Has any confirmed or suspected clinical immunodeficiency syndrome or has a family history of congenital or hereditary immunodeficiency unless confirmed absent in the participant