Comparing duration of response and duration of clinical benefit between fulvestrant treatment groups in the CONFIRM trial: application of new methodology.

Comparisons of duration of response (DoR) and duration of clinical benefit (DoCB) within clinical trials are prone to biases. To address these biases, we used new methodology to prospectively analyze expected DoR and expected DoCB. Objective response rate and clinical benefit rate were calculated for fulvestrant 500 and 250 mg, and used to calculate expected DoR and expected DoCB for each dose group.