Many people believe that phase I trials with healthy volunteers are very risky and because they pose risks with no benefits, unethical. But how risky are such trials? Less than 1% of 11,000 healthy volunteers who participated in 394 phase I trials for new drugs experienced serious complications, according to a new meta-analysis of participants in non-cancer, phase I medication trials. In addition, none of the volunteers died or suffered persistent disabilities linked to the experimental drugs.

Source: Serious adverse events rare in healthy volunteers participating in phase I drug trials