Assessing and communicating the risks and benefits of gene transfer clinical trials.

The two most important ethical requirements for clinical studies of gene transfer are to ensure that: (i) a protocol's risks are minimized and acceptable in light of the potential benefit to society and to research participants; and that (ii) a valid, informed consent process takes place. The history of gene transfer studies in humans shows that the probability of harm or benefit to participating individuals is extremely low. However, because the risks and benefits of gene transfer remain unpredictable, and because increasing the potential for benefits to individuals is likely to be accompanied by increases in potential for adverse events, close monitoring of human gene transfer research will continue. Recent research on informed consent for phase I studies of serious illnesses has revealed an evolving discussion on the proper standards for disclosure; one important conclusion is that disclosures regarding potential benefits to individuals need to be less ambiguous than they currently are.