Experimental Multiple Sclerosis Drug Shows Best in Class Efficacy Potential

Ocrelizumab may shift MS treatment paradigm.

Based on the results of a pair of recent phase 3 trials, the landscape for multiple sclerosis (MS) treatment may soon shift.

Roche announced this week that its experimental relapsing remitting multiple sclerosis drug ocrelizumab met the primary endpoint in two phase 3 studies showing superior reduction of annual relapse rate (ARR) over a 2-year period, superior reduction of disability progression, and a significant reduction in MRI lesions compared standard-of-care interferon beta-1a (Rebif).

“Ocrelizumab showed remarkable improvements over a standard-of-care medicine across clinical and imaging endpoints in two pivotal studies,” Sandra Horning, MD, chief medical officer and head of Global Product Development said in a press release. “Ocrelizumab has the potential to make a meaningful difference for people with MS, a chronic and debilitating disease. Based on these compelling results, we plan to submit the data for review to US and EU regulatory authorities in the first quarter of 2016.”

Ocrelizumab is the first MS therapy to consistently beat Rebif on all metrics, which indicates best-in-class efficacy with comparable safety to Rebif.

Ocrelizumab is a humanized monoclonal antibody designed to selectively target CD20-positive B cells, which are thought to be a key contributor to myelin and axonal damage. The drug binds to CD20 cell surface proteins expressed on some B cells, but not on stem cells or plasma cells.

As a result, patients treated with ocrelizumab are able to maintain the ability to produce new B cells.

The 2 randomized, double-blind, double-dummy, global multi-center studies evaluated the efficacy and safety of ocrelizumab in a 600 mg dose administered by intravenous infusion every 6 months compared with interferon beta-1a in a 44 mcg dose administered by subcutaneous injection 3 times per week. The primary endpoint of the studies was annualized protocol-defined relapse rate at 2 years.

The secondary endpoints included time to onset for disability progression, the total number of T1 Gadolinium-enhancing lesions, and the total of new and/or enlarging T2 hyperintense lesions. The studies enrolled 1656 relapsing forms MS patients across 307 sites in 40 countries, but the details of the findings were not released. Roche is expected to present the data at a medical conference later this year.

Adverse events associated with ocrelizumab were similar to interferon beta-1a in both studies, with the most common side effect being mild-to-moderate infusion-related reactions.