DOES A PLACEBO-EFFECT EXIST IN CLINICAL-TRIALS ON MULTIPLE-SCLEROSIS - REVIEW OF THE LITERATURE

To verify whether the outcome in placebo-treated MS patients actually corresponds to that expected on the basis of the natural history and p retrial evolution of the disease, we here review the results of clinic al trials conducted according to a placebo-controlled, randomized desi gn, regardless of the experimental therapy used. The frequency of rela pse in remitting-relapsing patients decreases during follow-up, and di sability in progressive cases increases more slowly than before enroll ment. These data should be borne in mind when evaluating the impact of experimental drugs on the natural course of the disease.