Multidisciplinary considerations for implementing Bayesian borrowing in basket trials.

• Key areas to be evaluated for the application of borrowing are an understanding of the disease groups being studied, the drug mechanism of action, and the measurement that will be borrowed. • Our framework puts each of these domains on a four-category ordered scale indicating the ability to justify applying borrowing. • Scoring of these domains considers them all to be equally important, and the overall evaluation will be dominated by the lowest score across domains. Drug development has historically relied on phase I–III clinical trials including participants sharing the same disease. However, drug development has evolved as the discovery of mechanistic drivers of disease demonstrated that the same therapeutic target may provide benefits across different diseases. A basket trial condenses evaluation of one therapy among multiple related diseases into a single trial and presents an opportunity to borrow information across them rather than viewing each in isolation. Borrowing is a statistical tool but requires a foundation of clinical and therapeutic mechanistic justification. We review the Bayesian borrowing approach, including its assumptions, and provide a framework for how this approach can be evaluated for successful use in a basket trial for drug development. [ABSTRACT FROM AUTHOR]