Copolymer 1 (glatiramer acetate) in relapsing forms of multiple sclerosis: open multicenter study of alternate-day administration.

Daily 20-mg doses of Copolymer 1 have been shown to significantly decrease the relapse rate in patients with multiple sclerosis (MS). In the present open-label study, patients with relapsing MS were treated with the same dose of Copolymer 1 administered on alternate days. Sixty-eight patients were recruited: fifty-one and forty-one patients completed 1 and 2 years of treatment respectively. The relapse rate during the 2 years of treatment decreased by 80.8% compared with the 2 years before treatment (means, 0.56 +/- 1.02 versus 2.91 +/- 1.10, respectively; p < 0.0001). This lower rate is comparable with that obtained with daily open-label administration previously reported by the authors. The score on the Expanded Disability Status Scale did not differ from that at baseline after the first year of treatment, although it increased somewhat at the end of the second year (baseline = 2.72 +/- 1.55, 1 year = 2.71 +/- 1.59, 2 years = 2.97 +/- 1.80; p < 0.008). The drug was very well tolerated. This preliminary open-label study suggests that alternate-day therapy has beneficial effects and is well tolerated, comparing favorably with the effects of daily injections of Copolymer 1 in patients with relapsing MS. These results should be confirmed by randomized double-blind examinations.