<qa>  What was the response rate of patients treated with MFP?The first clinical trial to evaluate antiprogestin therapy in patients recruited 22 patients for a third-line study. Patients were treated with MFP, 200 mgday, for 1-3 months. There was an 18 response rate following 3 months of therapy. The long-term tolerance was good. Three other studies were reviewed together with unpublished results from a fifth study . There are no other published clinical results for breast cancer treatment using MFP. 