The Lancet editorial notes the potential of phase 0 studies, but raises questions about their ethics: "no therapeutic benefit can be conferred by the small doses in a phase 0 study, and while taking part, patients are not allowed to enrol in a trial with therapeutic intent." As I have argued in Journal of Law, Medicine, and Ethics, however, the former issue is a red herring: normal phase 1 trials routinely, and deliberately, deliver levels of drug that are too low to cause therapeutic response. Moveover, whether phase 1 trials in themselves have "therapeutic intent" is debatable.
There are, of course, many ethical concerns surrounding phase 0 studies. Chief among them is whether patients understand their nontherapeutic nature, and whether results are publicly reported (I predict that if phase 0 methods are taken up by the private sector, many results will languish in filing cabinets). But effective engagement with ethical issues in phase 0 cancer studies requires, in my view, that we take a more careful look at whether "therapeutic intent" is really the litmus that determines whether a study pursued in patients is ethical. (photo credit: w i n t e r t w i n e d 2009)