Multiple Sclerosis 15 June 2004, vol. 10, no. Supplement 1, pp. 65-72(8)
K J.S.W.; The Promise Trial StudyGroup
University of Texas Health Science Center at Houston, Houston, TX, USA
The PROMiSe trial is a multinational, multicentre, double-blind, placebo-controlled trial evaluating the effects of glatiramer acetate treatment over 3 years in patients with primary progressive multiple sclerosis (PPMS).
A total of 943 patients were enrolled, and all those remaining on-study had completed at least 24 months as of October 2002.
Baseline clinical and MRI characteristics and select correlations are reported here.
A total of 3.9% of patients exhibited confirmed relapse over 1904 patient-years of exposure, indicating success of efforts to exclude relapsing MS types.
Of the 26.3% of patients who have prematurely withdrawn from the study, only 36% discontinued after meeting the study primary endpoint of disease progression.
The progression rate in patients in the low Expanded Disability Status Scale (EDSS) stratum (3.0-5.0) observed thus far is markedly lower than the 50% annual progression rate estimate used for determining size and statistical power of the trial; progression was observed in 16.1% of patients with 12 months of study exposure.
These early findings raise some concern about the ability of the trial to demonstrate a significant treatment effect, and suggest that the short-term natural history of PPMS may not be as aggressive as previously assumed.