Clinical outcomes of patients with multiple sclerosis treated with ocrelizumab in a US community MS center: an observational study

BACKGROUND: To monitor long-term outcomes of ocrelizumab treatment. OBJECTIVE: To evaluate safety and treatment outcomes of ocrelizumab in a community-based multiple sclerosis (MS) population. METHODS: Adult patients with MS prescribed ocrelizumab were eligible. Chart reviews were conducted at the start of ocrelizumab treatment and every 6 months thereafter. RESULTS: Of the 355 patients enrolled, 71.9% were female; mean (SD) age was 51.8 (12.5) years; 78.3% had relapsing MS (RMS). Median baseline Expanded Disability Status Scale (EDSS) (IQR) was 3.0 (2.0-4.0) for RMS, 6.5 (6.0-7.5) for secondary progressive MS, and 6.5 (6.0-7.0) for primary progressive MS. Respiratory infections occurred in 40.1% and urinary tract infections in 33.1% of patients. There was no difference in the percentage of infections among patients <55 (68.5%, n=122), and those ≥55 of age (67.5%, n=104) (p=0.94). Twenty-five hospitalisations were due to infections; 69.2% of these patients were ≥55 with a mean EDSS of 5.7 (±1.86). Four patients have died. Serum IgM and IgG levels did not predict infection risk. Annualised relapse rate was 0.34 for the patients with RMS in the preceding 2 years and 0.09 in patients who received ≥2 ocrelizumab 600 mg courses. The first on-treatment MRI was stable in 262 (90.0%) patients, 6.9% had new T2 lesions, 2.7% had enlarging T2 lesions and 1.4% had gadolinium-enhancing lesions. Median EDSS at 12 months was unchanged. CONCLUSION: Ocrelizumab effectively controlled relapse risk and disability worsening. Although only 12.1% of patients have discontinued ocrelizumab, infections resulting in hospitalisation are a concern, especially in older and disabled patients.