Ocrelizumab is a humanized monoclonal antibody that selectively targets CD20+ B lymphocytes, resulting in their depletion. It was approved in 2017 for relapsing-remitting and primary-progressive MS. Pooled safety analysis from clinical trials revealed an increase incidence of infection, infusion reaction (IR), and neoplasms in ocrelizumab treatment groups. We present a real-world safety analysis of ocrelizumab.

Subjects treated with ocrelizumab at the University of Florida were identified by chart review of electronic records. Longitudinal safety laboratories including and clinical data including disease course, prior disease modifying therapies, IRs and other adverse events (AE) were compiled. This data was analyzed to assess for trends in laboratories and occurrence of AEs.

Thirty-nine of a potential 200 patients have been reviewed thus far. The most common abnormal laboratory values after initiation of Ocrelizumab were leukocyte, neutrophil, lymphocyte, and T-cell counts, as well as decreased immunoglobulin-A and immunoglobulin-M levels. Nine subjects were diagnosed urinary tract infections, 3 with respiratory tract infections and 2 with abscesses. Two subjects were hospitalized for sepsis and appendicitis respectively. Ocrelizumab was discontinued in one patient due to pneumonia. Most infections occurred in subjects above 55 years old. Twelve IRs were reported, and treatment was discontinued in 1 subject due to bronchospasm. One subject was diagnosed with breast cancer and another with uterine fibroma.

Our data revealed that infections and IRs are common amongst patients treated with ocrelizumab, while neoplasms were rare. Though infusion reactions were common, they were mild and resolved quickly. Treatment discontinuations were due to serious IR and pneumonia, but were uncommon. These factors are important to consider when selecting treatment for patients with MS. More data is needed to corroborate trends in laboratory values and potential correlation with AEs.