The FDA has approved a new Genentech multiple sclerosis drug, ocrelizumab (Ocrevus), that will become the first ever marketed therapy for the most severe form of the disease.
Multiple sclerosis comes in different forms characterized by the severity and progression of the disease. While many drugs are available to treat MS, up until now, none have worked on people with the “primary progressive” form of the disease, which can lead to a rapid decline in patients’ ability to walk, speak, and function. Of the more than 2.3 million people affected by MS worldwide, approximately 15 percent are diagnosed with primary progressive form of the disease, according to the National Multiple Sclerosis Society.
Ocrelizumab, a drug from Genentech, a South San Francisco-based division of Swiss pharmaceutical company Roche, is now the first approved therapy for primary progressive MS patients. The drug is also approved for a relapsing form of MS, characterized by periods of partial recovery followed by additional attacks.
MS affects the body’s nerves but the disease is caused by the immune system. It’s not clear why but the body’s immune cells attack myelin, the fatty substance that covers nerve cells. Earlier MS drugs try to mitigate this attack by targeting the body’s T cells. The Genentech drug targets a different cell, the B cell.
The FDA based its approval of the Genentech drug on the results of three Phase 3 clinical trials. In the two trials testing the drug in patients with relapsing-remitting MS, ocrelizumab led to lower relapse rates than treatment with standard of care interferon beta-1a. In a third clinical trial of primary progressive patients, the drug slowed patients’ progression towards disability—measured by the volume of lesions in the brain and the patient’s performance on a timed 25-foot walk—compared to a placebo.
The drug, an injectable antibody administered twice a year, has a list price of $65,000 per patient, per year.
The FDA had deferred an approval decision roughly three months ago, citing a request for more details about how the drug is manufactured. But those concerns weren’t about the data. In January, the New England Journal of Medicine published results from the Phase 3 studies, describing the drug’s effect in slowing the progression of disability for primary progressive patients—the first drug to do so. That made the trial “a landmark study in the field,” the Journal wrote in an accompanying editorial.
In a research note issued this morning, Jefferies analyst Jeffrey Holford wrote that the Genentech drug will immediately become the standard of care for patients who have primary progressive MS. The drug’s label does include a warning for progressive multifocal leukoencephalopathy, a rare and potentially fatal viral infection in the brain that can occur in patients who have weakened immune systems, though Holford noted that no such cases were observed in clinical trials. The drug could snatch away market share held by MS drugs sold by Sanofi (NYSE: [[ticker:SNY]]) and Biogen (NASDAQ: [[ticker:BIIB]]), he wrote, but then again some of Biogen’s losses could be offset by a royalty Genentech will have to pay the Cambridge, MA, company for ocrelizumab sales.
Geoffrey Porges, an analyst at Leerink Partners, added in a research note that the $65,000 per year list price of ocrelizumab is a 10 to 25 percent discount to the prices of Biogen’s portfolio of MS drugs, including the MS drug dimethyl fumarate (Tecfidera). While dimethyl fumarate is a pill and Genentech’s drug an IV injection, Porges noted that it only needs to be given every six months, which offers “remarkable convenience for patients.” But Porges cautioned that if a patient were to get a dangerous infection with ocrelizumab, it would be difficult to reverse the drug’s effect and fight it off.
The most common side effects seen in ocrelizumab’s Phase 3 clinical trials were reactions at the site of the infusion and mild to moderate upper respiratory tract infections. Genentech plans to launch the drug “within two weeks,” according to a company statement.
Photo of Genentech sign by Rajiv Patel via a Creative Commons license.