Multi-arm clinical trials of new agents: some design considerations.

A major challenge in the development of anticancer therapies is the considerable time and resources needed for conducting randomized clinical trials (RCT). There is a need for more efficient RCT designs that accelerate development, minimize costs, and make trials more appealing to patients. We review the statistical and logistical characteristics of multi-arm designs that compare several experimental treatments to a common control arm. In particular, we present a rationale for not requiring multiplicity adjustment in multi-arm trials that are designed for logistical efficiency. Relative to conducting separate RCTs for each experimental agent, this multi-arm design is shown to require a lower total sample size than multiple two-arm trials.