AegirBio AB (publ) announced the findings of recent study published in the Multiple Sclerosis and Related Disorders journal. The research sheds light on the importance of understanding the interaction between a drug called natalizumab and a protein in the body called IgG4 for patients undergoing this treatment. Natalizumab is used to treat relapsing-remitting multiple sclerosis (MS), a condition affecting the central nervous system.

The study, conducted in partnership with the Rocky Mountain Multiple Sclerosis Center at the University of Colorado, focused on how the levels of IgG4 in patients impact the effectiveness of natalizumab. The study examined blood serum and saliva samples from a small group of MS patients. Researchers measured levels of intact natalizumab, total natalizumab, IgG, and IgG4.

Thefindings revealed that when IgG4 levels are high, the rate at which natalizumab interacts with other molecules in the body increases. This interaction reduces the amount of intact natalizumab available, which can weaken the drug's effectiveness in treating MS. Interestingly, the study also showed that saliva samples can be a useful non-invasive tool for monitoring natalizumab levels in MS patients. The results from saliva samples closely matched those from blood serum samples, supporting the idea of using saliva to monitor treatment effectiveness.

Understanding these interactions is crucial for optimizing treatment outcomes for MS patients. For instance, the studyfound that patients with lower levels of IgG4 may have higher concentrations of intact natalizumab, even if their total natalizumab levels are lower. This insight could help explain why some patients experience a rare brain infection called progressive multifocal leukoencephalopathy (PML) while on natalizumab treatment.