FACT: An Open-Label Randomized Phase III Study of Fulvestrant and Anastrozole in Combination Compared With Anastrozole Alone as First-Line Therapy for Patients With Receptor-Positive Postmenopausal Breast Cancer.

Abstract

PURPOSE To compare the effect of therapy with anastrozole versus a combination of fulvestrant and anastrozole in women in first relapse of endocrine-responsive breast cancer. PATIENTS AND METHODS Postmenopausal women, or premenopausal women receiving a gonadotropin-releasing hormone agonist, with estrogen receptor- and/or progesterone receptor-positive disease at first relapse after primary treatment of localized disease were open-label randomly assigned to a fulvestrant loading dose (LD) regimen followed by monthly injection plus 1 mg of anastrozole daily or to 1 mg of anastrozole daily alone. The primary end point was time to progression (TTP). RESULTS: 63 patients (24.6%) versus 35 patients (13.8%) in the standard arm (P = .0023). Death owing to AEs was reported in 11 (4.3%) and five patients (2.0%) in the experimental versus standard arm, respectively. CONCLUSION Fulvestrant (250 mg + LD regimen) in combination with anastrozole offered no clinical efficacy advantage over anastrozole monotherapy in this population of individuals with a relatively high proportion of previous adjuvant antiestrogen exposure.