1st Potential Therapy for Primary Progressive MS, Ocrelizumab, Under Priority Review by FDA

The U.S. Food and Drug Administration (FDA) is giving priority review to a request to approve Ocrevus (ocrelizumab) as a treatment for both forms of multiple sclerosis, the drug’s developer, Genentech, announced. If the company’s Biologics License Application (BLA) is approved, Ocrevus will become the first drug able to treat patients with either relapsing or primary progressive MS.

By designating the review a priority, the FDA will make its decision within six months rather than the standard 10, and release that decision on Dec. 28. Approval means the drug will be available for patients in the U.S.

A similar regulatory process is underway in Europe, with the European Medicines Agency (EMA) having approved the company’s Marketing Authorization Application (MAA) for Ocrevus and taken it under review for use throughout the European Union.

“OCREVUS is the first investigational medicine to significantly reduce disability progression in people with relapsing and primary progressive forms of MS,” Sandra Horning, MD, chief medical officer and head of Global Product Development at Genentech, said in a press release. “We are pleased by the FDA’s decision to classify their review of the BLA as priority, because we believe OCREVUS has the potential to help people living with either of these two forms of MS.”

Although a number of treatments already exist for relapsing MS, none are able to treat the disease’s primary progressive form. An estimated 95 percent of all MS patients are diagnosed with either one of these two types.

Genentech’s applications for U.S. and EU approval of Ocrevus are based on three randomized, double-blind, and large Phase 3 clinical trials. OPERA I and OPERA II were identical studies that demonstrated Ocrevus’ superior efficacy in patients with relapsing MS (RMS) compared to Rebif therapy (interferon beta-1a). Ocrevus was shown to decrease annual relapse rate by almost 50%, and to reduce the total number of new or enlarging brain lesions by 77% and 83%, respectively, in the two studies. Furthermore, half of the patients on ocrelizumab therapy had no evidence of relapses, disability progression and brain lesion activity, compared to 25% to 30% of the patients taking Rebif.

Data from the ORATORIO trial, in primary progressive MS patients (PPMS), demonstrated significant reductions in disability progression and reduced brain atrophy compared to placebo. In all three trials, Ocrevus therapy was set at 600 mg given by intravenous infusion every six months.

Ocrevus (ocrelizumab) is a humanized monoclonal antibody designed to selectively target CD20-positive B cells, a type of immune cell thought to contribute to the myelin (a nerve cell insulator) and nerve cell (axonal) damage that results in MS. The therapy is designed to bind to CD20 cell surface proteins expressed on certain B-cells, although not to stem cells or plasma cells, so as to preserve key immune system functions.