Two-stage plans for patient accrual in phase II cancer clinical trials.

This paper considers two-stage patient-accrual plans for phase II trials of anticancer drugs. The purpose is to identify the therapeutic level of drugs as either above or below a reference response rate. Using such a plan, decisions concerning the future disposition of drugs can be made more formally and objectively. The tables used to implement the plan are prepared for a 20% reference response rate, due to its wide acceptance in the design of phase II clinical trials.