Assessing Phase I clinical trials

This paper challenges the common view that, when investigating a new drug or treatment, we should always first investigate only the toxicity or safety of the treatment—conduct a so-called Phase I trial. It examines the arguments for investigating safety only, before any investigation of efficacy, and argues that early clinical trials that investigate both safety and efficacy (hybrid Phase I/II trials) are almost always superior—at least ethically—to Phase I trials.