Purpose: Fulvestrant ('Faslodex') is an oestrogen receptor (ER) antagonist with no agonist effects. The drug was administered to heavily pre-treated patients with advanced breast cancer (ABC). Patients received Fulvestrant after disease progression (PD) on a previous endocrine treatment or as maintenance treatment after chemotherapy.
Material and methods: Fifty-seven postmenopausal women with ER and/or progesterone receptor-positive ABC resistant to previous endocrine treatments prospectively received fulvestrant 250 mg via intramuscular injection q 28.
Results: Twenty-seven patients received fulvestrant after PD and 30 received it as maintenance therapy after chemotherapy. All patients received fulvestrant as second-up to eight-line endocrine treatment for ABC. One patient (2%) had a partial response (PR) and 24 patients (42%) had stable disease > or =12 weeks (SD), including 11 patients who had SD > or =24 weeks. Thirty-two patients (56%) had de novo PD. Clinical benefit (CB; PR + SD > or =24 weeks) occurred in 12 patients (21%). Patients treated as maintenance and treated upon PD had 0 and 4% PR, 43 and 41% SD (including 20 and 19% SD > or =24 weeks), 57 and 55% PD, respectively. Overall, median time to progression (TTP) was 3 months. No differences in CB rate (20% vs. 23%), TTP (3 months vs. 3 months) and time to treatment failure (3 months vs. 3 months) were observed between patients receiving fulvestrant as maintenance therapy and those treated at PD on prior endocrine treatment. No grade 2-4 NCI-CTC toxicity was recorded.
Conclusions: Fulvestrant treatment was associated with prolonged CB and was well tolerated in this group of heavily pre-treated patients with ABC. The outcomes appeared to be similar for patients treated upon PD and those receiving fulvestrant as maintenance therapy.