Genentech announced the FDA has accepted the company’s biologics license application (BLA) for satralizumab for the treatment of adults and adolescents with neuromyelitis optica spectrum disorder (NMOSD). The European Medicines Agency (EMA) has also validated the company’s Marketing Authorization Application (MAA) for satralizumab, granting it accelerated assessment. The FDA decision and the EMA’s Committee for Medicinal Products for Human Use (CHMP) recommendation are expected in 2020.
“People living with NMOSD experience unpredictable relapses that can cause permanent neurological damage, and although there have been significant strides recently in understanding the disease, more approved options are needed with different treatment approaches. Satralizumab has shown robust efficacy sustained for 96 weeks and significantly reduced the risk of relapse across a broad patient population, while offering self-administered subcutaneous dosing every four weeks,” Levi Garraway, MD, PhD, chief medical officer and head of Global Product Development, said in a company news release. “The FDA and EMA’s acceptances of the satralizumab applications bring us one step closer to providing a new medicine to thousands of people impacted by NMOSD, and we are working with the health authorities to make satralizumab available as soon as possible.”
The satralizumab applications are based on positive results from two phase 3 studies, SAkuraStar and SAkuraSky, evaluating the efficacy and safety of satralizumab as a monotherapy and in combination with baseline immunosuppressant therapy, respectively. In the SAkuraStar study, satralizumab monotherapy achieved a 55% reduction in the risk of relapses compared to placebo in the overall study population of aquaporin-4 antibody (AQP4-IgG) seropositive and seronegative patients (Hazard Ratio [HR]=0.45, 95% Confidence Interval [CI]: 0.23-0.89; p=0.0184). Satralizumab achieved a 74% reduction (HR=0.26, 95% CI: 0.11-0.63; p=0.0014) in the larger (~67%) subgroup of AQP4-IgG seropositive patients, who tend to experience a more severe disease course. In the overall satralizumab-treated population, 76.1% were relapse-free at 48 weeks, and 72.1% relapse-free at 96 weeks, compared to 61.9% and 51.2% with placebo, respectively. Data from the AQP4-IgG seropositive subgroup showed that 82.9% were relapse-free at 48 weeks and 76.5% relapse-free at 96 weeks when treated with satralizumab, compared to 55.4% and 41.1% with placebo, respectively.
Additionally, the SAkuraSky study data showed a 62% reduction in the risk of relapses compared to placebo in the overall study population (HR=0.38, 95% CI: 0.16-0.88; P=0.0184) when used in combination with baseline immunosuppressant therapy, and a 79% reduction in the risk of relapses in AQP4-IgG seropositive patients (HR=0.21, 95% CI: 0.06-0.75; P=0.0086). In the overall satralizumab-treated population, 88.9% were relapse-free at 48 weeks, and 77.6% were relapse-free at 96 weeks, compared to 66.0% and 58.7% with placebo, respectively. Data from the AQP4-IgG seropositive subgroup showed that 91.5% were relapse-free at 48 and 96 weeks when treated with satralizumab, compared to 59.9% and 53.3% with placebo, respectively.
Overall, the proportion of patients with serious adverse events was similar between the satralizumab and placebo treatment groups in both studies. A lower rate of infections (including serious infections) was observed in patients treated with satralizumab compared with the placebo group. Most adverse events were mild to moderate, and the most common adverse events in the satralizumab group were urinary tract infection and upper respiratory tract infection in the SAkuraStar study and upper respiratory tract infection, nasopharyngitis (common cold) and headache in the SAkuraSky study.
The FDA previously granted Breakthrough Therapy Designation to satralizumab for the treatment of NMOSD in December 2018.