Johnson & Johnson has announced the release of data suggesting a favorable clinical profile for nipocalimab, a novel treatment for immunoglobulin G (IgG)-driven diseases including fetal and neonatal alloimmune thrombocytopenia (FNAIT). Their findings were summarized in a recent press release.
Nipocalimab is a monoclonal antibody designed to bind to and inhibit the neonatal Fc receptor (FcRn), a protein that helps transport maternal antibodies to the fetus to provide passive immunity to the child. In patients with FNAIT, maternal antibodies that attack fetal platelets are transferred into fetal circulation via this receptor, resulting in diminished platelet levels. By blocking FcRn, these maternal antibodies may be prevented from travelling to the fetus’ bloodstream, thereby averting thrombocytopenia.
The results demonstrated that nipocalimab reduces levels of IgG by over 75%, with stronger effects observed over time and at higher doses of the drug. Furthermore, the drug did not appear to impair any other immune functions, and IgG production appeared unaltered in preclinical studies. Thus, nipocalimab may offer a safety advantage over immunosuppressive drugs, such as steroids, that are sometimes prescribed to patients affected by FNAIT.
The study also found that nipocalimab selectively targets FcRn, binding with a high-level of affinity. Notably, binding affinity was found to be unaffected by varying pH levels.
Read more about FNAIT therapies
The researchers then analyzed the mechanism of action of the drug both in-vitro and in-vivo, finding the observed mechanism to be consistent with data from prior Phase 1, 2 and 3 clinical trials. However, they note that the clinical impact of the drug on patients remains unclear.
In March 2024, the U.S. Food and Drug Administration (FDA) granted Fast Track designation, which expedites the drug review process, to nipocalimab for patients with FNAIT. The drug has not yet been been approved by the FDA, though.
Sign up here to get the latest news, perspectives, and information about FNAIT sent directly to your inbox. Registration is free and only takes a minute.
