Riliprubart Receives Orphan Drug Status in Japan for Chronic Inflammatory Demyelinating Polyneuropathy

The Japanese Ministry of Health, Labour and Welfare (MHLW) has recognized riliprubart with orphan drug status, a significant step for individuals suffering from chronic inflammatory demyelinating polyneuropathy (CIDP). This monoclonal antibody operates by selectively inhibiting activated C1s in the classical complement pathway, specifically targeting those with CIDP, a rare neurological disorder. Despite existing therapies, a notable portion of CIDP patients continue to endure symptoms such as weakness, numbness, and fatigue, which can severely affect their quality of life and lead to long-term disability. In Japan alone, around 4,000 individuals are diagnosed with CIDP, with 30% of these patients not responding to standard treatments.

Orphan drug status in Japan is granted to medications that address rare diseases or conditions where significant medical needs remain unmet. The award of this designation to riliprubart reflects broader international regulatory acknowledgment, having already received similar designations from authorities in the US and Europe. Erik Wallstroem, MD, PhD, the Global Head of Neurology Development at Sanofi, emphasized the company's dedication to leveraging its expertise in the immune system to tackle rare neurological disorders, highlighting that many CIDP patients continue to experience debilitating symptoms despite available treatments.

Notably, riliprubart demonstrated sustained long-term efficacy and safety in a 76-week phase 2 study, with the results presented at a recent Peripheral Nerve Society meeting in Edinburgh, UK. The findings suggest that riliprubart might offer prolonged benefits across a diverse group of CIDP patients. Currently, the drug is undergoing two phase 3 trials: the MOBILIZE study involving patients unresponsive to standard care and the VITALIZE study focusing on those treated with intravenous immunoglobulin (IVIg).

Riliprubart, known scientifically as SAR445088, is a humanized monoclonal antibody of the IgG4 type that specifically targets the C1s component in the classical complement pathway. By doing so, it potentially inhibits inflammatory mechanisms that contribute to demyelination and axonal injury in CIDP. While currently in clinical trials, its safety and efficacy have not yet received evaluation by any regulatory body.

CIDP itself is characterized by progressive weakness and sensory loss in the limbs due to the immune system attacking the myelin sheaths surrounding peripheral nerve cells. Prompt diagnosis is crucial, as it allows for appropriate treatment, which is vital to preventing long-term disability. Despite the presence of treatments, many patients experience persistent symptoms that can significantly affect their daily lives. Only a small percentage of those with CIDP achieve complete remission without ongoing treatment.

Sanofi, the company behind riliprubart's development, is a biopharmaceutical entity driven by research and development and enhanced by artificial intelligence. The company is committed to improving global health through innovative medicines and vaccines. Guided by their mission to advance scientific frontiers, Sanofi aims to make significant contributions to healthcare by addressing pressing challenges with an innovative pipeline aimed at benefitting millions worldwide.