Fulvestrant versus anastrozole for the treatment of advanced breast carcinoma: a prospectively planned combined survival analysis of two multicenter trials.
BACKGROUND
Fulvestrant is an estrogen receptor antagonist with no agonist effects. In the second-line treatment of advanced breast carcinoma, fulvestrant was shown previously to be as effective as the third-generation aromatase inhibitor, anastrozole, in terms of time to disease progression and objective response rates. The authors reported the overall survival results from these studies.


METHODS
A prospectively planned, combined, overall survival analysis was performed, including data from two Phase III trials that compared the efficacy and tolerability of fulvestrant (250 mg monthly; n = 428) with anastrozole (1 mg daily; n = 423) in the treatment of postmenopausal women with advanced breast carcinoma who had disease progression after receipt of previous endocrine treatment.


RESULTS
At an extended median follow-up of 27.0 months (range, 0-66.9 months), 319 (74.5%) patients in the fulvestrant group and 322 (76.1%) patients in the anastrozole group had died. Prolonged survival was observed with both drugs, with 10-20% of patients still alive > 5 years after randomization. The median overall survival was similar between treatments, being 27.4 months and 27.7 months in fulvestrant and anastrozole-treated patients, respectively (hazards ratio, 0.98; 95% confidence interval, 0.84-1.15; P = 0.809). Fulvestrant continued to be well tolerated, and was associated with a significantly lower incidence of joint disorders compared with anastrozole (P = 0.0234).


CONCLUSIONS
The current analysis showed that fulvestrant was similar to anastrozole with respect to overall survival in the second-line treatment of postmenopausal women with advanced breast carcinoma.
Howell
Anthony
A
Department of Medical Oncology, Cancer Research UK, Christie Hospital, Manchester, United Kingdom. maria.parker@christie-tr.nwest.nhs.uk
Pippen
John
J
Elledge
Richard M
RM
Mauriac
Louis
L
Vergote
Ignace
I
Jones
Stephen E
SE
Come
Steven E
SE
Osborne
C Kent
CK
Robertson
John F R
JF
D000077384:Anastrozole; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D047072:Aromatase Inhibitors / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy*; D018572:Disease-Free Survival; D004311:Double-Blind Method; D004958:Estradiol / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004965:Estrogen Antagonists / Q000627:therapeutic use; D005260:Female; D000077267:Fulvestrant; D006801:Humans; D009570:Nitriles / Q000009:adverse effects / Q000627:therapeutic use*; D017698:Postmenopause; D016019:Survival Analysis; D015996:Survival Rate; D014230:Triazoles / Q000009:adverse effects / Q000627:therapeutic use*
D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D004965:Estrogen Antagonists; D009570:Nitriles; D014230:Triazoles; D000077267:Fulvestrant; D000077384:Anastrozole; D004958:Estradiol