When Johnson & Johnson acquired nipocalimab as part of the $6.5 billion takeover of Momenta Pharmaceuticals, the hype surrounding the therapy was focused on its potential as a treatment for the hot disease area of myasthenia gravis. But a top-line phase 2 readout for the drug in a fetal disorder is a reminder that nipocalimab could have a far broader reach.
Nipocalimab is the only therapy in clinical development for the treatment of alloimmunized pregnant adults at risk of severe hemolytic disease of the fetus and newborn. The rare autoantibody-driven disease results in the mother’s antibodies crossing the placenta and attacking fetal red blood cells, which can cause fetal hemolysis and anemia.
In this unusual indication is where the anti-Fc receptor antibody has hit its primary endpoint. Specifically, the majority of the 14 pregnant patients who received once-weekly intravenous infusions of nipocalimab achieved a live birth at or after 32 weeks of gestation, without the need for an intrauterine transfusion throughout their entire pregnancy.
Over the roughly 20-week treatment period, nipocalimab’s safety profile supported further development of the drug in this fetal indication, J&J said in a release Monday morning. Katie Abouzahr, M.D., autoantibody portfolio development leader at Janssen Research & Development, said more data will be released at an upcoming scientific medical meeting, while the company plans for a pivotal phase 3 study.
J&J’s willingness to pay well over $6 billion for Momenta back in 2020 reflected the Big Pharma’s belief that nipocalimab could secure multiple blockbuster launches. The interest in the Fc receptor reflected evidence of the role the target plays in the action of autoantibodies, a type of antibody that reacts with self-antigens, in a range of autoimmune diseases.
While nipocalimab has the field to itself for severe hemolytic disease in alloimmunized pregnant adults, there are plenty of competitors when it comes to myasthenia gravis, a rare long-term condition that causes muscle weakness. But even here the race became slightly less crowded last week when Sanofi revealed it had dropped its candidate, a BTK inhibitor called tolebrutinib.
Alexion, now part of AstraZeneca, won approval for Soliris in myasthenia gravis in 2017 before following up with an OK for Ultomiris last year. In between those approvals, argenx secured the green light to sell Vyvgart in the U.S. UCB has filed for approval of two molecules, zilucoplan and rozanolixizumab, in the indication.
J&J is following close behind, with the phase 3 trial of nipocalimab scheduled to get to primary completion by the end of the year. Elsewhere, the drug has a busy schedule, with phase 2 trials in idiopathic inflammatory myopathy, rheumatoid arthritis, systemic lupus erythematosus and Sjogren's syndrome, as well as phase 3 studies in warm autoimmune hemolytic anemia and chronic inflammatory demyelinating polyneuropathy.