Agent Shows Promise in Multiple Sclerosis

Data reported at ECTRIMS International Conference show a significant benefit was seen for patients with highly active MS on alemtuzumab.

Genzyme Corporation reported yesterday five-year patient data from its completed Phase 2 multiple sclerosis (MS) trial. This sub-group analysis found that nearly 90 percent of alemtuzumab-treated patients were free of sustained accumulation of disability, and that patients receiving alemtuzumab also maintained improved mean disability scores and a low risk of relapse over the 60-month follow-up period. The majority of alemtuzumab patients received their last course of treatment at month 12 in the study. These accumulated efficacy and safety data were presented in Sweden at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) annual meeting, one of the largest annual international MS conferences.

The CAMMS223 Phase 2 trial, first reported in the New England Journal of Medicine in 2008, compared alemtuzumab to the approved MS therapy Rebif® (high dose interferon beta-1a) in early, active, relapsing-remitting multiple sclerosis (RRMS) patients who had received no prior therapy. In the trial, alemtuzumab was given to patients in two or three annual cycles of not more than five days per cycle, while Rebif was given to patients three times per week, every week for three years.

Results at 60 months of patient follow-up found that:

• Alemtuzumab-treated patients demonstrated consistently lower annualized relapse rates over the entire observation period compared to those treated with Rebif. Annualized relapse rate was 0.11 in those receiving alemtuzumab, compared with 0.35 in patients receiving Rebif.
• The mean disability (EDSS) score for patients receiving alemtuzumab improved, but worsened for patients receiving Rebif.
• Over the 60-month study period, 13 percent of patients receiving alemtuzumab experienced a sustained increase in disability compared with 38 percent of patients taking Rebif.

“These long-term patient follow-up data suggest that alemtuzumab may have a significant disease modifying effect in patients with early, active, relapsing-remitting multiple sclerosis,” said Alasdair Coles, MD, Senior Lecturer, Department of Clinical Neurosciences, University of Cambridge, a lead investigator of the Phase 2 clinical trial and author of the 5-year review abstract.

“We appreciate the tremendous dedication of the patients, physicians, and nurses participating in this important trial, who enabled us to obtain these five-year data,” said Mark Enyedy, Genzyme president for Transplant, Oncology and Multiple Sclerosis. “Their efforts have provided further insights into the potential of alemtuzumab to improve long-term outcomes for patients with multiple sclerosis.” The CAMMS223 Phase 2 trial was larger and follow-up was longer than the typical Phase 2 MS trial.

Strong Benefit Seen in Patients with Highly Active Multiple Sclerosis

A second abstract presented at ECTRIMS found that patients in the Phase 2 trial with highly active RRMS had a significantly decreased annualized relapse rate when receiving alemtuzumab compared to Rebif.

Results at 36-months of patient follow-up found that:

• Annualized relapse rate was significantly reduced for patients receiving alemtuzumab. Annualized relapse rate was 0.09 in patients receiving alemtuzumab as compared with 0.47 in those receiving Rebif, a reduction of 81 percent.
• 91 percent of alemtuzumab-treated patients were free of sustained accumulation of disability, compared to 75 percent of patients taking Rebif.

More than half of the patients enrolled in the Phase 2 trial had highly active RRMS: 56 percent of alemtuzumab treated patients, and 55 percent of Rebif treated patients. Patients with highly active disease had at least two relapses in the year prior to treatment in the trial, and had at least one gadolinium enhancing brain lesion identified through magnetic resonance imaging (MRI).

“In this Phase 2 trial, alemtuzumab was significantly more effective than Rebif at reducing relapses and the accumulation of disability in patients with highly active disease, a population at a typically higher risk for poor MS outcomes,” said Dean Wingerchuk, M.D., Department of Neurology, Mayo Clinic.

Genzyme is conducting two pivotal Phase 3 trials to evaluate alemtuzumab in the treatment of MS. CARE-MS I, a randomized trial comparing alemtuzumab to Rebif, is studying early, active RRMS patients who have received no prior therapy. CARE-MS II, which also compares alemtuzumab to Rebif, is studying RRMS patients who relapsed while on other MS therapies. Data from the Phase 3 trials are expected to be available in 2011.

Alemtuzumab is an investigational drug for the treatment of MS and must not be used in MS patients outside of a formal, regulated clinical trial setting in which appropriate patient monitoring measures are in place.

About CAMMS223 Phase 2 Study

In the Phase 2 trial, 334 patients with active RRMS were randomized to treatment with alemtuzumab at one of two dose levels, or Rebif. The majority of patients last received alemtuzumab at Month 12. Patients were strongly encouraged to continue for two additional years of follow-up beyond the original three years of the study.

Sixty-eight percent of alemtuzumab patients participated in the follow-up program, and 60 percent were evaluated at 60 months. Forty-two percent of Rebif patients participated in the follow-up program, and 35 percent were evaluated at 60 months. Rater-blinded disability scores were assessed quarterly and relapses as-needed. A sensitivity analysis adjusted for patients receiving alternative disease-modifying therapy during the follow-up period, as well as for retreatment with alemtuzumab.

Source: Genzyme