Genentech, a member of the Roche Group, announced data this week from the Phase III PEMPHIX study evaluating the efficacy and safety of Rituxan® (rituximab) compared to mycophenolate mofetil (MMF) in adults with moderate to severe pemphigus vulgaris (PV). The study met the primary endpoint at week 52 and demonstrated that Rituxan is superior to MMF, with 40.3% of patients treated with Rituxan achieving sustained complete remission (CR) without the use of steroids for 16 consecutive weeks or more, compared to 9.5% in the MMF arm (p<0.0001). All secondary endpoints were statistically significant in favor of Rituxan: lower cumulative oral corticosteroid dose (mean difference: 1595 mg; p=0.0005), fewer flares (6 vs. 44, p<0.0001), a greater likelihood of sustained CR (hazard ratio [HR]=4.83; p=0.0003), a lesser likelihood of flare (HR=0.15; p<0.0001) and a greater improvement in the Dermatology Life Quality Index (DLQI) at week 52 (estimated mean change from baseline -8.87 vs. -6.00, p=0.0012) compared to the MMF arm. Adverse events were generally consistent with those seen in previous Rituxan clinical studies in PV and other approved autoimmune indications.
“The approval of Rituxan for the treatment of pemphigus vulgaris was the first major advancement in the treatment of this rare, serious disease in more than 60 years,” said Levi Garraway, M.D., Ph.D., chief medical officer and head of Global Product Development. “The PEMPHIX study showed that 40% of people in the study could achieve complete remission from painful blistering without the need for corticosteroids for 16 weeks or more and that Rituxan may be a superior treatment option to mycophenolate mofetil.”
The study is ongoing, with patients participating in a 48-week safety follow-up period after treatment completion or discontinuation.