Rare Daily Staff

Japan’s Ministry of Health, Labor and Welfare has approved the extension of the current marketing authorization of Alexion Pharmaceuticals Soliris to include the prevention of relapse in patients with anti-aquaporin-4 (AQP4) antibody-positive neuromyelitis optica spectrum disorder (NMOSD), including neuromyelitis optica.

NMOSD is a rare complement-mediated disorder of the central nervous system characterized by relapses. Each relapse results in stepwise accumulation of disability that include blindness and paralysis, and sometimes premature death. Patients who have anti-AQP4 auto-antibodies represent approximately three quarters of all patients with NMOSD.

There are currently no approved therapies for this disease.

“We are pleased that the Japanese health authorities have approved Soliris as a new treatment for patients suffering from this complex and unpredictable disease,” said John Orloff, executive vice president and head of Research and Development at Alexion. “Nearly all patients treated with Soliris were relapse free at 48 weeks in the phase 3 PREVENT study, providing new hope for Japanese patients with NMOSD and their clinicians.”

Soliris, eculizumab, is a first-in-class complement inhibitor that works by inhibiting the C5 protein in the terminal part of the complement cascade, a part of the immune system. The terminal complement cascade, when activated in an uncontrolled manner, plays a role in severe rare and ultra-rare disorders.

The approval of Soliris was based on comprehensive results from the phase 3 randomized, double-blind placebo controlled PREVENT trial, and a long-term extension study that is still underway.  The results demonstrated that Soliris reduced the risk of NMOSD relapse by 94.2 percent compared to placebo. At 48 weeks, 97.9 percent of patients receiving Soliris were free of relapse compared to 63.2 percent of patients receiving placebo. Soliris was generally well tolerated with a safety profile consistent with that seen in previous clinical studies and real-world use in its three approved indications.

“The understanding of NMOSD has rapidly evolved in recent years since complement activation by AQP4 antibodies was identified as an underlying cause of the disease,” said Kazuo Fujihara, professor at Fukushima Medical University, director of the Multiple Sclerosis & Neuromyelitis Optica Center at Southern Tohoku Research Institute, and a principal investigator in the PREVENT trial. “With the first approved medicine for NMOSD in Japan, Soliris will provide highly effective treatment to prevent future relapses in these patients.”

Soliris was approved for the treatment of NMOSD in adult patients who are anti-AQP4 antibody-positive by the U.S. Food and Drug Administration in June 2019 and by the European Commission in August 2019. It received Orphan Drug designation for the treatment of NMOSD in the U.S., EU and Japan.

Photo: John Orloff, executive vice president and head of Research and Development at Alexion

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