Roche has released more data showing that its multiple sclerosis drug Ocrevus works better than Merck's Rebif against the relapsing form of the disease, and also has potential in controlling the primary progressive type, bringing further hope of the first approved treatment option for this subset of patients.

According to the data, Ocrevus (ocrelizumab) significantly increased the proportion of relapsing patients achieving 'no evidence of disease activity' (NEDA) by 75 percent versus Rebif (interferon beta-1a) over 96 weeks, and the relative proportion of those achieving NEDA by 33 percent in weeks 0-24 and by 72 percent in weeks 24-96.

"Controlling clinical and sub-clinical disease activity as early as possible is an important treatment goal for people living with MS," said Professor Gavin Giovannoni, Scientific Steering Committee Member of the OPERA I and II studies and chair of Neurology at Barts and The London School of Medicine and Dentistry.

"These new data suggest that ocrelizumab consistently impacts disease progression and has the potential to change how we approach treating both relapsing and primary progressive MS."

Also, a new post-hoc analyses of the ORATORIO study showed that Ocrevus significantly increased the number of patients with primary progressive MS (PPMS) who experienced 'no evidence of disease progression' (NEP) - which includes three measures of physical disability and reflects no evidence of worsening of a person's physical disability - by 47 percent at week 120 compared with placebo.

"With no approved treatment options, primary progressive MS remains a challenge for physicians and people with MS," said Xavier Montalban, Professor of Neurology and Neuroimmunology at Vall d'Hebron University Hospital, Research Institute and Cemcat, Barcelona, Spain. "Ocrevus significantly impacted three key disability measurements, which further highlight its clinical significance in people with primary progressive MS."

Ocrevus is an investigational, humanised monoclonal antibody designed to selectively target CD20-positive B cells, thought to be a key contributor to myelin and nerve cell damage, which can cause disability in patients with MS.

According to Roche, the fact that efficacy has been shown across both forms of MS "validates the hypothesis that B cells are central to the underlying biology of the disease".

The drug has been filed on both sides of the Atlantic and is currently undergoing a priority review in the US, with a decision expected by the end of December.