Keywords: Estimand, Oncology
A draft addendum of the ICH E9 guideline on Statistical Principles for Clinical Trials was released in August 2017 and introduced an estimand framework. The new framework aims at aligning trial objectives and statistical analyses by requiring a precise definition of the inferential quantity of interest, the estimand. In clinical trials this corresponds to the definition of the treatment effect, in particular explicitly accounting for events which occur after baseline but before observing the endpoint of interest, e.g. start of another therapy. The addendum is anticipated to have a major impact on drug development, as the choice of the estimand will drive the trial design and sample size, data collection, trial conduct, and analysis. Furthermore, the framework will support discussions among sponsors, regulators, payers, physicians, and patients about relevant treatment effects, interpretation of study results, and added value of drugs. This talk outlines key issues in implementing estimand framework in oncology drug development from a regulatory perspective.