Overall success rate of a safe and efficacious drug: Results using six phase 1 designs, each followed by standard phase 2 and 3 designs

Without data informing the shape of the dose-toxicity curve, nonstandard phase 1 designs with a modified excessive toxicity rule more easily eliminating unsafe dose levels are recommended. With this modification, MTD overestimation error decreased and overall success rates were similar or higher with nonstandard designs. Among nonstandard designs, the modified CCD and BOIN perform well and are as transparent and simple to implement as the standard 3 + 3 design.