The Food and Drug Administration (FDA) has approved the supplemental Biologics License Application (sBLA) for a shorter 2-hour infusion time for Ocrevus® (ocrelizumab; Genentech) for patients with relapsing or primary progressive multiple sclerosis (MS).

The approval was based on data from the randomized, double-blind phase 3b ENSEMBLE PLUS study that compared the frequency and severity of infusion-related reactions for a 2-hour Ocrevus infusion time to the previously approved 3.5-hour infusion time in patients with relapsing-remitting MS. Patients received the approved initial dosing schedule of two 300mg intravenous (IV) infusions separated by 2 weeks followed by subsequent doses of 600mg IV infusion over a shorter 2-hour time every 6 months. 

The primary end point was the proportion of patients with infusion-related reactions following the first randomized 600mg infusion; frequency and severity were assessed during and for 24 hours after the infusion.

Results showed that the frequency of infusion-related reactions was comparable between the 2-hour (24.6%) and 3.5-hour infusion times (23.1%). The majority of reactions were mild or moderate and greater than 98% resolved in both treatment arms without complication. There were no discontinuations due to infusion-related reactions and no new safety signals were detected. 

Ocrevus, a CD20-directed cytolytic antibody, has been associated with infusion reactions such as pruritus, rash, urticaria, erythema, bronchospasm, throat irritation, oropharyngeal pain, dyspnea, pharyngeal or laryngeal edema, flushing, hypotension, pyrexia, fatigue, headache, dizziness, nausea, tachycardia, and anaphylaxis. Across multiple trials, the incidence of infusion reactions in treated patients was observed to be 34-40% with the highest incidence linked to the first infusion. To reduce the frequency and severity of infusion reactions, it is recommended that patients be premedicated with methylprednisolone and an antihistamine; an antipyretic may also be considered.

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1.    FDA approves Genentech’s Ocrevus (ocrelizumab) shorter 2-hour infusion for relapsing and primary progressive multiple sclerosis. [press release]. South San Francisco, CA: Genentech; December 14, 2020. 

2.    Ocrevus [package insert]. South San Francisco, CA: Genentech; 2020.