The randomized placebo-phase design for clinical trials.

Randomized controlled trials are the criterion standard method for evaluating the effectiveness of medical treatments. There are situations, however, where the possibility of being in the control group in a randomized controlled trial is unacceptable to potential subjects or their physicians. This lack of acceptance is a reason for poor accrual. We developed and validated a new clinical trial design for survival data that may allay concerns about not receiving an investigational product and should be more acceptable. Called the randomized placebo-phase design, this new design asks whether, on average, those subjects who begin active treatment sooner respond sooner than those who begin it later. Using Monte Carlo computer simulations, we demonstrated that the design is valid and may offer advantages over traditional randomized controlled trials in some situations. The randomized placebo-phase design may be especially useful when highly potent therapies for rare diseases are tested or when accrual may be otherwise difficult.