Annualized relapse rates (ARR) in the placebo cohorts of phase-3 randomized controlled trials (RCT) of new treatments for relapsing remitting multiple sclerosis (RRMS) have decreased substantially during the last two decades. The causes of these changes are not clear. We consider a better understanding of this phenomenon essential for valuing the effects of new drugs and by designing new trials.
Annualized relapse rates (ARR) in the placebo cohorts of phase-3 randomized controlled trials (RCT) of new treatments for relapsing remitting multiple sclerosis (RRMS) have decreased substantially during the last two decades. The causes of these changes are not clear. We consider a better understanding of this phenomenon essential for valuing the effects of new drugs and by designing new trials.