Clinical Trials Arena

J&J publishes nipocalimab Phase II HDFN data as Phase III continues enrolment

The Phase II trial of J&J’s nipocalimab met its primary endpoint, with 54% of the pregnant women achieving a live birth at or after 32 weeks gestational age.

Johnson & Johnson (J&J) has published results from the Phase II UNITY trial evaluating nipocalimab in pregnant women at high risk of developing haemolytic disease of the foetus and newborn (HDFN).

The company first reported positive data for nipocalimab in HDFN from its Phase II UNITY trial (NCT03842189), in June 2023. The company is currently recruiting participants in the Phase III AZALEA trial (NCT05912517) in HDFN.

HDFN commonly occurs when rhesus (RhD) negative maternal blood with antibodies against rhesus D antigen enters the foetal bloodstream, leading to immune haemolysis of foetal/neonatal red blood cells. The maternal antibodies are formed due to a blood transfusion or previous pregnancy. Thereby, increasing the risk of severity of immune response with subsequent pregnancies.

Treatment for HDFN is prophylactic, with RhD-negative pregnant women receiving prophylaxis with Rh immunoglobulins if their foetus was confirmed to be RhD positive, according to the UK’s National Health Service (NHS).

The UNITY trial evaluated the use of nipocalimab in 13 pregnancies at high risk for recurrent early-onset severe HDFN. Seven of the pregnancies resulted in a live birth at or after 32 weeks gestational age without the need for an intrauterine transfusion (IUT). Furthermore, 92% of the pregnancies resulted in live births and only 85% of the participants required IUT.

J&J has had a run of success with nipocalimab. The therapy has also proven effective in two rare disease indications – generalised myasthenia gravis (gMG) and Sjogren’s disease. In February, the company reported the Phase III and II trials evaluating nipocalimab met primary endpoints in gMG and Sjogren’s disease, respectively.

Nipocalimab is an IgG-specific monoclonal antibody that can selectively block neonatal fragment crystallisable receptor (FcRn) to reduce levels of circulating IgG antibodies, including autoantibodies. J&J acquired the therapy through the acquisition of Momenta Pharmaceuticals for $6.5bn in 2020. The therapy received a breakthrough therapy designation in HDFN from the US Food and Drug Administration (FDA) in February.

J&J is also evaluating nipocalimab as a treatment for foetal and neonatal alloimmune thrombocytopenia (FNAIT), a rare immune disorder where maternal alloantibodies bind to the infant’s platelets and cause their destruction during pregnancy and after birth. The company is currently recruiting pregnant participants at risk of developing FNAIT in a Phase III FREESIA-1 trial (NCT06449651).