Ocrelizumab

Parent companies: Genentech, Roche Pharma AG

• Ocrelizumab is administered via intravenous infusion.
  
  
• Like Rituxan, this drug is an anti-CD20 monoclonal antibody. It has the potential advantage of being a more humanized antibody than Rituxan.
  
  
• In a Phase II study of ocrelizumab in 220 patients with RRMS, reductions in the total number of brain lesions detected by MRI scans (the primary endpoint of the study) were highly significant at 96 percent for 2,000-mg ocrelizumab and 89 percent for 600 mg compared to placebo. The annualized relapse rate was significantly lower versus placebo at week 24, with a reduction of 73 percent for ocrelizumab 2,000 mg and 80 percent for ocrelizumab 600 mg. Ocrelizumab's effectiveness was maintained through week 72; the proportion of relapse-free patients at week 72 was 84 percent for the 600-mg group and 82 percent for the 2,000-mg ocrelizumab group. Long-term safety data are not yet available.
  
  
• The Phase III ORATORIO safety and efficacy study of ocrelizumab in 630 patients with PPMS is currently recruiting participants. Patients will receive either ocrelizumab (300 mg given intravenously in two infusions separated by 14 days in each treatment cycle) or placebo. The study is scheduled for March 2011 to August 2017. The primary outcome measure is time to onset of sustained disability progression (for at least 12 weeks); secondary outcome measures include the time to sustained disability progression (for at least 24 weeks), change in the total volume of T2 lesions (as seen on MRI), as well as safety, tolerability, and the incidence of adverse events.
  
  
• A Phase III study to evaluate the safety and efficacy of ocrelizumab in comparison with Rebif in 1,000 individuals with RRMS is not yet open to participants. It was scheduled to begin in April 2011 and for completion in November 2014. The primary outcome measure is annualized relapse rate; secondary measures include time to onset of sustained disability progression, the proportion of relapse-free patients, MRI measures of disease activity, and change in MSFC Scale.