10-year clinical results with continuous glatiramer acetate

A 10-year follow-up assessment of participants in an ongoing glatiramer acetate study has found that those who continued to use the drug over the decade had significantly less disability than those who withdrew from treatment before follow-up.The US Glatiramer Acetate Trial began in 1991 and is described by the authors as unique in that it is the only ongoing, open-label study of more than 10 years' duration to prospectively evaluate continuous immunomodulatory therapy in relapsing-remitting MS patients. The study began with a double-blind, placebo-controlled phase for a mean of 30 months, in which participants were assigned either daily glatiramer acetate (20mg) or placebo injection. At the end of the double-blind phase, all patients were offered active treatment in an open-label phase. Previously-reported results showed that, at 8-year follow-up, patients who began active treatment during the double-blind phase had better outcomes than those who were first assigned placebo and thus did not receive active therapy until 2.5 years later, when they commenced the open-label phase of the trial. This new report describes the long-term experience with the drug in all patients who received it during the double-blind and/or open-label phases of the study. It also describes the differences in outcomes between those who continued therapy over 8-10 years and those who discontinued therapy and withdrew from the study.A total of 108 participants remaining in the study and on glatiramer acetate and 50 of the 124 patients who had withdrawn from the drug and the study agreed to a 10-year follow-up visit to assess disability status and relapse rates. Mean glatiramer acetate exposure was 10.1 years for patients still using glatiramer acetate and 4.26 years in patients who had withdrawn from the study. The authors report, "At 10 years after beginning GA therapy, all measures indicated that Withdrawn with ?Elong-term follow-up?I patients fared significantly worse than Ongoing patients!KDisability measures indicated these Withdrawn patients worsened over time, regardless of whether, how long, or which immunomodulatory therapy they took after leaving the study." Compared with patients who continued therapy, EDSS increases were significantly higher in patients who had withdrawn. While on glatiramer acetate, relapse rates were reduced by over 80% from rates at the start of therapy, to a rate of approximately one relapse every five years, and nearly all patients remained ambulatory.Reference...