Natalizumab Treatment for Relapsing-Remitting Multiple Sclerosis: The Experience From Saudi Arabia

Natalizumab is the first targeted humanized monoclonal antibody to be approved for the treatment of relapsing-remitting multiple sclerosis (RRMS). Natalizumab appears to be more effective than current first-line disease-modifying therapies. In our study, we aimed to evaluate the outcome of Saudi patients with active RRMS treated with natalizumab and compare the results with other outcomes in the Gulf and international trials.

We conducted a retrospective single-center observational study involving 32 patients with RRMS at King Abdulaziz Medical City in Jeddah, Saudi Arabia. The inclusion criteria included all patients diagnosed with RRMS according to the revised McDonald criteria who are currently receiving or received natalizumab treatment in the past for a minimum of 6 months.

The mean baseline Expanded Disability Status Scale score was 4.50 ± 1.80 (range, 1.5-6; median, 5), whereas the mean Expanded Disability Status Scale at the follow-up was 4.02 ± 2.08 (range, 1-6; median, 4.25) (P = 0.3274). The mean annualized relapse rate was significantly reduced from 2.41 ± 2.48 at baseline to 0.16 ± 0.37 at the last follow-up (P < 0.0001). Twenty-seven patients (84.4%) had no relapses since the treatment with natalizumab was started, whereas 5 patients (15.6%) had only 1 relapse. In addition to clinically measurable improvement, radiological improvement was observed through magnetic resonance imaging. Magnetic resonance imaging activity was significantly improved at follow-up magnetic resonance imaging studies when compared with baseline.

Our single-center study in Saudi Arabia provides further support for the efficacy of natalizumab in the clinical practice setting. The sharp decrease in relapse rate and progression of disability following the initiation of natalizumab treatment was similar to other observational studies conducted in different countries across the globe. Natalizumab was a satisfactory therapy for the management of our MS population, both from the patients' and the physicians' perspectives.