A Phase 3 Randomized, Placebo-Controlled, Double-Blind, Multicenter Study to Evaluate the Efficacy and Safety of Nipocalimab in Pregnancies at Risk for Severe Hemolytic Disease of the Fetus and Newborn (HDFN).

The primary objective of this Phase 3 randomized, placebo-controlled, double-blind, multicenter study is to evaluate the **efficacy** of **nipocalimab** compared with placebo in reducing the risk of fetal anemia in pregnant participants at risk for severe **Hemolytic Disease of the Fetus and Newborn (HDFN)**. This is clinically relevant as fetal anemia is a significant complication of HDFN, which can lead to severe morbidity or mortality in neonates. By assessing the potential of nipocalimab to mitigate this risk, the study aims to provide insights into a novel therapeutic approach for managing pregnancies complicated by severe HDFN.

The clinical trial involves a total of **92 participants** who are exclusively female, aged between **18 to 45 years**. The study population comprises pregnant women at risk for severe **Hemolytic Disease of the Fetus and Newborn (HDFN)**. Participants were selected based on specific criteria, including a history of severe HDFN in a prior pregnancy and the presence of maternal alloantibody to RhD, Kell, Rhc, RhE, or RhC antigen with titers above critical levels. The trial focuses on a vulnerable population, as it involves pregnant women. The participants' general health status is not specified beyond the inclusion criteria related to HDFN risk. Lifestyle considerations such as diet, physical activity, or habits are not detailed in the available data.

The clinical trial is a **Phase 3**, randomized, double-blind, placebo-controlled, multicenter study designed to evaluate the efficacy and safety of **nipocalimab** in pregnancies at risk for severe **Hemolytic Disease of the Fetus and Newborn (HDFN)**. The primary objective is to assess the ability of nipocalimab to reduce the risk of fetal anemia in pregnant participants. The trial is expected to commence recruitment on January 31, 2024, and conclude by July 10, 2029, with a maximum treatment period of 23 weeks for each participant.

Participants will be randomly assigned to receive either nipocalimab or a placebo, administered as a **solution for infusion** via **intravenous use**. The study will include several key visits: an initial screening visit to confirm eligibility based on inclusion criteria such as age, pregnancy status, and history of severe HDFN, followed by regular follow-up visits to monitor the health of both the mother and fetus. The end-of-study visit will assess the final outcomes and any adverse events.

The expected duration of participant involvement is up to 23 weeks, aligning with the treatment period. Conditions that may lead to early termination from the study include significant adverse reactions, withdrawal of consent, or any medical condition that, in the investigator's opinion, would compromise the participant's safety or the integrity of the study. The trial will adhere to rigorous ethical standards and regulatory requirements to ensure the safety and well-being of all participants.

The clinical trial involves the administration of **nipocalimab**, an experimental medication, under the product code JNJ-80202135. Nipocalimab is provided in two pharmaceutical forms: a **solution for infusion** and a **solution for injection**. The active substance, nipocalimab, is a protein classified as a monoclonal antibody targeting the neonatal Fc receptor. The medication is administered via **intravenous use**. The dosing schedule and specific dosage units are not explicitly defined in the provided data, but the maximum treatment period is specified as 23 weeks. The trial aims to evaluate the efficacy of nipocalimab in reducing the risk of fetal anemia in pregnancies at risk for severe Hemolytic Disease of the Fetus and Newborn (HDFN).

In addition to the experimental treatment, a **placebo** is utilized in the study, specifically a **Saline, 0.9% Sodium Chloride Solution for Injection**. This placebo serves as a comparator to assess the efficacy of nipocalimab. The saline solution is administered in a manner consistent with standard clinical practices for placebo administration in intravenous studies. The use of a placebo is integral to maintaining the double-blind nature of the trial, ensuring unbiased assessment of the treatment's efficacy and safety.

The efficacy of **nipocalimab** in the clinical trial will be assessed by evaluating its ability to reduce the risk of fetal anemia in pregnant participants at risk for severe Hemolytic Disease of the Fetus and Newborn (HDFN). The primary endpoint is the comparison of nipocalimab with placebo in achieving this reduction, with the outcome measured by the presence of live neonates. The trial is designed as a Phase 3 randomized, placebo-controlled, double-blind, multicenter study. The assessment of efficacy will involve the collection and analysis of data related to fetal anemia, which is a critical condition in pregnancies affected by severe HDFN. The trial will utilize central laboratory results to confirm the presence of maternal alloantibodies and antigen positivity, which are essential for determining the risk of fetal anemia. The study is scheduled to begin recruitment on January 31, 2024, and is estimated to conclude by July 10, 2029.