Phase II Randomized, Multicenter, Crossover Clinical Trial for Administration of Exemestane vs. Anastrozole as First Line Treatment for Postmenopausal Patients With Hormone Receptor Positive Advanced Breast Cancer
The primary study endpoint is objective response rate. The study has been designed following
Simon's test, with a p1-p0=0.15. p1 is the optimum level of activity of the experimental
treatment (exemestane), and p0 is the minimum expected activity. In this study, p1 is 25%
(25% of RR) and p0 is 10% (10% of RR). With an alpha error of 0.05 and a beta error of 0.1,
Simon test establishes a first step of 21 patients per treatment arm. If at least 2
objective responses are observed in exemestane arm, recruitment will continue until 100
patients have been recruited. After this second recruitment phase, at least 7 objective
responses must be observed to confirm the expected exemestane level of activity.
Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Crossover Assignment, Masking: Open Label, Primary Purpose: Treatment
Overall response rate
Antonio Llombart, MD., PhD.
Spanish Breast Cancer Research Group
Spain: Spanish Agency of Medicines