Potential Myasthenia Gravis Treatment Receives FDA Priority Review

The Food and Drug Administration (FDA) has granted Priority Review designation to the Biologics License Application (BLA) for nipocalimab (Johnson & Johnson, New Brunswick, NJ) for the treatment of people with generalized myasthenia gravis (gMG) who are antibody positive, including anti-acetylcholine receptor (AChR), anti-muscle–specific tyrosine kinase (anti-MuSK), and anti-lipoprotein–related protein 4 (anti-LRP4) antibodies. Nipocalimab is an experimental monoclonal antibody which reduces circulating immunoglobulin G (IgG) antibodies by binding with neonatal Fc receptor proteins.

The FDA based its decision on findings from the multicenter, randomized, double-blind, placebo-controlled phase 3 Vivacity-MG3 clinical study (NCT04951622), which evaluated the safety and efficacy of nipocalimab treatment for people with gMG. Vivacity-MG3 included 199 adult participants with antibody positive (n=153) or negative (n=46) gMG with insufficient response to ongoing treatment using standard of care (SOC). Participants were randomized 1:1 to receive either nipocalimab (n=77) or placebo (n=76) by intravenous (IV) infusion in addition to current SOC.

The primary outcome measure was average change from baseline to weeks 22 through 24 in Myasthenia Gravis–Activities of Daily Living (MG-ADL) score for participants who were antibody positive. People who received nipocalimab and SOC showed a ≥2-point reduction in MG-ADL score compared with placebo (P=.0213), representing a significant reduction in the impacts of gMG. An ongoing open-label extension (OLE) is assessing long-term safety and efficacy.

“We are committed to working closely with the FDA to help bring nipocalimab as a potential treatment to certain patients living with gMG, and we especially thank the participants in the Phase 2 and 3 studies,” said Katie Abouzahr, MD, Vice President of the Autoantibody Portfolio and Maternal Fetal Immunology Disease Area Leader at Johnson & Johnson Innovative Medicine. “If approved, nipocalimab has the potential to treat gMG in antibody positive individuals, including anti-AChR, anti-MuSK, and/or anti-LRP4.”