A drug similar to rituximab will soon be available to people with MS

Roche Pharmaceuticals, the owner of Genentech, announced positive phase III study results of their anti-CD20 monoclonal antibody called Ocrelizumab yesterday. Ocrelizumab is a humanized monoclonal antibody targeting CD20 on mature B cells, whereas Rituximab is a Chimeric antibody (part mouse and part human) with the same target. This clears the way for FDA approval of Ocrelizumab by late 2015 or early 2016. The two phase III studies involved 1656 relapsing MS patients (both relapsing remitting and secondary progressive) randomized to either an Ocrelizumab infusion every 6 months (600 mg) or Rebif 44 mcg three times a week. Ocrelizumab significantly reduced relapse rates, new lesion formation on MRI and disability progression during the two years of the study compared to Rebif. Amazingly, serous adverse events associated with Ocrelizumab were not more common than serious adverse events with Rebif, a drug considered very safe and a first line therapy for MS. The most common adverse events with Ocrelizumab were infusion related reactions, which can be controlled with premedication. A phase III study of Ocrelizumab in primary progressive MS is still underway.

Why is this important?

1. Many people with MS who have benefited from Rituximab in the past or could benefit from it now are no longer able to receive it because of  insurance restrictions. These study results open the way for FDA approval of this class of medication

2. Only one other MS medication (Lemtrada) has shown significant benefits on relapse rates, disability progression and MRI activity over 2 years when compared to a highly active first line DMT (Rebif). Remember, it is relatively easy to be better than placebo treatment. Not only is Ocrelizumab better than Rebif, it is relatively safe and well tolerated over 2 years of treatment. A full understanding of the relative benefits and risks of Ocrelizumab awaits final release of the actual study data for us to review, but the statements in their press release are very exciting. 

3. Any treatment that can be administered as infrequently as every 6 months will be welcome to most MS patients

4. Depending on our review of the study data, this drug may benefit certain secondary progressive MS patients

All are cause for celebration.

Revere (Rip) Kinkel MD
Director of the Multiple Sclerosis Program
University of California San Diego