Roche says its investigational drug ocrelizumab is the first to show clinically meaningful and statistically significant efficacy in patients with difficult-to-treat primary progressive multiple sclerosis.

According to Phase III data, the humanised monoclonal antibody reduced the progression of clinical disability and sustained this effect for at least 12 weeks versus placebo, raising hopes that the first approved therapy for this form of the condition could be just around the corner.

Ocrelizumab is designed to selectively target CD20-positive B cells. In another first, study results are showing efficacy across both PPMS (ORATORIO) and relapsing forms of MS (OPERA I and OPERA II), which Roche says “validates the hypothesis that B cells are central to the underlying biology of the disease”.

The Swiss drug giant confirmed that the drug’s filing, which has been pegged for early next year, will seek approval to market ocrelizumab for both primary progressive and relapsing MS, which could provide it with a major competitive edge over rival treatments.