Nipocalimab (M281; Johnson & Johnson) has received Breakthrough Therapy Designation (BTD) for managing the risk of severe hemolytic disease of the fetus and newborn (HDFN) in pregnant patients with alloimmunization by the FDA.
Takeaways
- Nipocalimab receives FDA Breakthrough Therapy Designation (BTD) for severe HDFN in pregnant patients, offering a significant treatment advancement.
- HDFN arises from maternal-fetal red blood cell incompatibility, leading to fetal anemia and neonatal complications if untreated.
- Nipocalimab selectively blocks FcRn, reducing circulating immunoglobulin G levels, providing a non-surgical intervention for HDFN.
- Positive results from the UNITY trial support the BTD, with most participants achieving live birth without intrauterine transfusion and minimal severe adverse events.
- Fast Track designation and orphan drug status accelerate nipocalimab's development, now advancing to phase 3 AZALEA trial for severe HDFN in pregnancy.
HDFN occurs in pregnancies when certain red blood cell types have maternal-fetal incompatibility. This causes alloantibodies from the maternal immune system to cross the placenta and attack fetal red blood cells, leading to fetal anemia. If HDFM persists after birth, it can cause neonatal hyperbilirubinemia and anemia.
Symptoms of HDFN may be mild such as jaundice, or more severe such as neurotoxic hyperbilirubinema and fetal anemia requiring invasive intervention. There are currently no non-surgical interventions against early-onset severe HDFM approved for use in the United States.
Nipocalimab is a monoclonal antibody developed to decrease circulating immunoglobulin G antibody levels by selectively blocking FcRn. It is the only antibody being evaluated across 3 key autoantibody segments. These include rare autoantibody diseases, maternal fetal diseases mediated by maternal alloantibodies, and prevalent rheumatology.
The BTD is supported by data from the phase 2 open-label UNITY clinical trial, evaluating the efficacy of nipocalimab in achieving live birth at or after 32 weeks’ gestation without intrauterine transfusion during pregnancy. This endpoint was met by a majority of participants, and severe adverse events were low and associated with pregnancy, HDFN, and gestational age at birth.
A Fast Track designation was given to nipocalimab in July 2019 and orphan drug status in June 2020. With the BTA, the development and regulatory review of the drug can accelerate. Nipocalimab in pregnant patients at risk of severe HDFM will be evaluated in the AZALEA phase 3 pivitol trial.
Reference
Johnson & Johnson's nipocalimab granted US FDA Breakthrough Therapy Designation for the treatment of individuals at high risk for severe hemolytic disease of the fetus and newborn (HDFN). Johnson & Johnson. February 9, 2024. Accessed February 9, 2024. https://www.prnewswire.com/news-releases/johnson--johnsons-nipocalimab-granted-us-fda-breakthrough-therapy-designation-for-the-treatment-of-individuals-at-high-risk-for-severe-hemolytic-disease-of-the-fetus-and-newborn-hdfn-302058561.html?tc=eml_cleartime
