[Introduction of anticancer agents to phase I clinical trials].

Because about half of patients with cancer could not be cured by the present standard therapy, new effective anticancer agents should be developed and introduced at the clinical level. However, there are several important and specific issues from scientific, medical, statistical, and ethical viewpoints in the design and conducting of phase I clinical trials of new anticancer agents. Clinical safety data management is critically important in phase I clinical trials. Phase I clinical trials are vastly different from phase II or III clinical trials in terms of these issues. This paper discusses issues of early anticancer drug development to be solved or improved.