1 Estimands and Their Role in Clinical Trials Frank Bretz (Novartis) EFSPI/PSI UK SeptemAcknowledgements ICH E9(R1) Expert Working Group M Akacha, D Ohlssen, H Schmidli, G Rosenkranz (Novartis) 1 EFSPI/PSI Frank Bretz SeptemEstimands and their role in clinical trialsĢ Aims of this talk Discuss the need for a new framework Illustrate the choice of estimands with real and hypothetical examples 2 EFSPI/PSI Frank Bretz SeptemEstimands and their role in clinical trialsģ Aims of this talk Discuss the need for a new framework Illustrate the choice of estimands with real and hypothetical examples 3 EFSPI/PSI Frank Bretz SeptemEstimands and their role in clinical trialsĤ Background Measure of treatment effect Clinical trials aim to draw inference about the benefit of a medicinal product Trialist selects an appropriate measure of treatment effect For example in a 2-arm diabetes study: Difference in change in HbA1c from baseline to 24 weeks based on all randomized patients Selection often does not account for post-randomization events, e.g.