Approved Beta Interferons in Relapsing-Remitting Multiple Sclerosis: Is There an Odd One Out?

Three interferons are marketed for the treatment of relapsing-remitting multiple sclerosis. In its pivotal trial, one of them demonstrated impressive efficacy as a once-weekly regimen, but later head-to-head studies and reviews questioned its superiority. Analysis of this pivotal trial in publications and health authority reviews has shown that its early termination might have caused attrition bias. Censored patients were different from those completing the study on magnetic resonance imaging parameters and benefited from placebo in terms of relapse rate. Early progression of disability and differences in follow-up duration could have favored the benefit observed for the progression of disability outcome. Only the raw data could be of help to confirm or refute doubts about this trial. Raw data should be made available to the scientific community.