September 24, 2008
Merck’s Phase IIIb Multiple Sclerosis Study Meets Endpoint
Merck Serono, a division of Merck KGaA, Darmstadt, Germany, has announced that the ongoing Improve study met its primary endpoint.
The primary objective of the Improve study was to evaluate the efficacy of the new formulation of Rebif, compared to placebo, in patients with relapsing-remitting multiple sclerosis (RRMS) and active disease by means of magnetic resonance imaging (MRI) at the end of 16 weeks of treatment. The 16-week study results show that the mean number of combined unique active brain MRI lesions per patient was reduced by 69% in patients treated with the new formulation of Rebif compared with those receiving placebo, a statistically significant result.
The Improve study is a two-arm, randomized, double-blind, controlled, multicenter, international Phase IIIb study to evaluate the efficacy, safety and tolerability of the new formulation of Rebif in patients with RRMS according to the revised McDonald criteria and evidence of active disease. A total of 180 patients were randomized in a 2:1 ratio to receive either the new formulation of Rebif 44 micrograms three times a week subcutaneously, or placebo for an initial period of 16 weeks.
At the end of this initial 16-week treatment period, patients from the placebo group have been switched in a single-blinded fashion to treatment with the new formulation of Rebif 44 micrograms three times a week subcutaneously for a period of 24 weeks (the physician assessing treatment response and side effects is blinded). Patients who were initially assigned to the new formulation of Rebif group continue to receive active treatment for an additional period of 24 weeks. The duration of the whole treatment period is 40 weeks.
The primary efficacy analysis showed that, at week 16, the number of combined unique active brain lesions was significantly lower in patients treated with the new formulation of Rebif than in patients who received a placebo (p
The median number of combined unique active brain lesions at week 16 was zero in the group treated with the new formulation of Rebif and one in the placebo group. Over half (53%) of patients treated with the new formulation of Rebif had zero combined unique active brain lesions at week 16, compared to only 16.7% in the placebo group.
The company has said that the results for the secondary and tertiary endpoints of the Improve study will be available at the end of the 40-week treatment period. The safety profile of the new formulation of Rebif reported in this study is consistent with the known safety profile of Rebif. No unexpected safety concerns were identified in this study.
Mark Freedman, investigator of the Improve trial, said: "These data demonstrate a significant effect of the new formulation of Rebif on disease activity and provide further evidence of its benefit in treating patients with relapsing-remitting multiple sclerosis."