ABSTRACT
Though many differing approaches for conducting phase I trials have been proposed over the past three decades, they all aim to target a specific dose level while minimizing the risk of patients in the trial experiencing intolerable toxicities. Here, we cover the two main types of phase I designs—rule-based and model-based—and provide an overview of the many designs available. We also discuss other design aspects, such as start-up rules and stopping rules, and summarize how clinical practice has changed over the years when it comes to designing a phase I trial.
