The FDA has approved Roche’s humanized monoclonal antibody ocrelizumab (Ocrevus) to treat adult patients with relapsing forms of multiple sclerosis (MS) and primary progressive multiple sclerosis (PPMS). Ocrelizumab is the first drug approved for PPMS, which is characterized by steadily worsening function from the onset of symptoms, often without early relapses or remissions.
About 15% of MS patients have PPMS. Ocrelizumab, which selectively inhibits CD20-positive B cells, is administered via intravenous infusion twice yearly after 2 initial 300 mg doses, a regimen that may be viewed as more convenient for patients. Most of the approved MS drugs are either pills or injectables, taken once or twice daily.
Analysts say ocrelizumab has the potential to earn more than $4 billion annually by 2022 and to be a “major market disrupter.” Roche said it was pricing the drug at an annual cost of $65,000 (that price does not account for rebates and discounts), which represents a 20% discount to the average price of other MS medications, the company noted. Roche intends to launch the drug in the US market in 2 weeks. It is currently under review by the European Medicines Agency.
The FDA granted ocrelizumab breakthrough therapy designation, priority review, and fast track designation. The 2 phase 3 studies of the drug involved 1656 participants treated for 96 weeks, which showed the drug significantly increased the length of time during which patients did not show signs of disease progression—relapse, confirmed disability progression, or new or enlarging lesions seen on MRI—compared with interferon beta-1a (Rebif). Ocrelizumab reduced the annual relapse rate by 50% compared with interferon beta-1a over 2 years. In a third phase 3 trial in patients with PPMS, which involved 732 participants and lasted at least 120 weeks, ocrelizumab performed better than placebo and could reduce signs of the disease, including the spread of MS lesions. The main results of all 3 trials were published in The New England Journal of Medicine.
Ocrelizumab can cause serious infusion-related reactions. The most common side effects of ocrelizumab seen in clinical trials of patients with relapsing-remitting MS were upper respiratory tract infection; for patients with PPMS, the most common reactions were upper respiratory tract infection, skin infection, and lower respiratory tract infection. Ocrelizumab is not recommended for use in patients with hepatitis B infection.