Adaptive Clinical Trials: Scientific and Ethical Issues to Consider

Article of Note: Journal of the American Medical Association

JAMA, June 13, 2012 – Vol. 307, No. 22

A recent issue of JAMA features two articles expressing viewpoints about adaptive trials in clinical research that may be of interest.

An adaptive clinical trial is one in which key characteristics, such as randomization ratio, number of treatment arms, and number of interim analyses conducted, are adjusted while enrollment in the trial is ongoing. The adjustments use prospectively defined decision rules, and they respond to the data accumulating in the trial. For example, using accumulating information can increase the probability that future trial participants are assigned to the study group with a better expected outcome, or the least effective drug doses may be eliminated earlier than in a fixed trial.

Broadly speaking, adaptive trials may minimize the harms to study participants and increase the likelihood that participants will directly benefit. However, understanding the performance characteristics of an adaptive trial may be challenging for both IRBs and trial participants.

In addition, scientific concerns about maintaining blinding (as researchers see trial design changes), as well as questions about whether adaptive trials can be replicated, remain challenges that may limit scientific validity.

For the full articles see http://jama.jamanetwork.com/journal.aspx