Genentech, a Roche company, released full data from its pivotal Phase III SAkuraStar trial of satralizumab as a monotherapy for neuromyelitis optica spectrum disorder (NMOSD). The company presented the data at the 35th Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS).
NMOSD is a rare, debilitating autoimmune disease of the central nervous system (CNS) that mostly damages the optic nerve and spinal cord. It leads to blindness, muscle weakness and paralysis. NMOSD patients have unpredictable, severe relapses that result in cumulative, permanent, neurological damage and disability, sometimes leading to death. The disease affects more than 10,000 people in Europe, 15,000 in the U.S. and up to hundreds of thousands worldwide. It is most common in non-Caucasian women in their 30s and 40s. It is often initially misdiagnosed as multiple sclerosis.
Satralizumab resulted in a 55% decrease in the risk of relapses compared to placebo in the overall patient population. In a subgroup, which actually made up about 67% of the patient population studied, who were seropositive for AQP4-IgG antibodies, the drug reduced the risk of relapses by 74%. Patients with those antibodies usually experience more severe symptoms.
“The positive Phase III results for satralizumab, first as an add-on therapy and now as a monotherapy are exciting to see, and importantly, it achieved efficacy in a broad range of NMOSD patients, reflective of what we see in our everyday practice,” said Jeffrey Bennett, with the University of Colorado Neurology & Ophthalmology. “Satralizumab targets the IL-6 receptor, potentially offering a novel treatment approach. Approved treatment options demonstrating favorable safety and efficacy in controlled clinical trials are urgently needed. Even one relapse may lead to blindness and debilitating motor dysfunction for people with NMOSD.”
In the broader cohort receiving satralizumab, 76.1% were relapse-free at 48 weeks compared to 61.9% in the placebo group. At the 96-week mark, 72.1% were relapse-free compared to 51.2% receiving placebo.
In the AQP4-IgG seropositive subgroup, 82.9% were relapse-free at 48 weeks compared to 55.4% in the placebo group, and at 96 weeks, 76.5% were relapse-free compared to 41.1% receiving placebo.
Satralizumab inhibits IL-6 signaling. This signaling is thought to play a major role in inflammation associated with NMOSD.
“While first described 125 years ago, the underlying biology of NMOSD has only recently been understood,” stated Sandra Horning, Roche’s chief medical officer and head of Global Product Development. “The positive results from the pivotal SAkuraStar and SAkuraSky studies support the hypothesis that IL-6 plays a key role in this devastating disease that can take away people’s independence. We are encouraged by these results and look forward to working with regulators over the coming months to bring satralizumab to people living with NMOSD as soon as possible.”
Data from the other trial, SAkuraSky were presented at the ECTRIMS meeting last year. SAkuraSky evaluated satralizumab in combination with baseline therapy in NMOSD. That trial showed a 62% decrease in the risk of relapses in the overall disease population compared to placebo and a 79% decrease in the AQP4-IgG seropositive subgroup.