Fulvestrant (‘Faslodex’) in pre-treated patients with advanced breast cancer: A single-centre experience

Fulvestrant (‘Faslodex’) is a new oestrogen receptor (ER) antagonist with no agonist effects. This report describes the experience of a single centre including 126 postmenopausal women with advanced breast cancer (ABC) in a fulvestrant Compassionate Use Programme. All patients had previously received endocrine treatment for early or ABC. Patients received fulvestrant as first- (n=7), second- (n=51), third- (n=50) or fourth-line endocrine therapy (n=18) for ABC (median duration of treatment: 4 months [range 3–27+ months], follow-up: 13 months [range 1–38+ months]). Twelve patients had partial responses (PR) and 43 patients experienced stable disease (SD) ⩾6 months (objective response rate: 9.5%; clinical benefit [CB] rate: 43.6%). Ten of 12 patients with a PR had HER2-negative tumours, and 9/12 had ER-positive and progesterone receptor (PgR)-positive disease (two patients had unknown HER2 status and one had unknown ER and PgR status). Nine of the 18 patients with HER2-positive tumours experienced CB with fulvestrant. Although CB rates were similar when fulvestrant was given as first- to fourth-line endocrine treatment, the proportion of those experiencing CB who had a PR appeared to decrease when fulvestrant was used later in the sequence. Fulvestrant was well tolerated; six patients experienced adverse events (all grade I/II). These data demonstrate that fulvestrant is an effective and well-tolerated therapy for patients with ABC progressing on prior therapies.