Pharmacological and clinical profile of anastrozole.
Anastrozole (Arimidex, 2,-2[5-(1H-1,2,4-triazol-1-ylmethyl)-1,3-phenylene]bis(2-met hyl)propiononitrile) is a novel, potent aromatase inhibitor belonging to the triazole class. In vitro and in vivo animal studies have revealed the drug to be a potent inhibitor of the aromatase enzyme with no inhibitory activity versus other enzymes involved in steroid synthesis. The drug is a potent suppressor of plasma estrogens in healthy male and postmenopausal female volunteers as well as postmenopausal breast cancer patients, and anastrozole administered as 1 mg or 10 mg daily has been shown to inhibit in vivo aromatization by 96.7 and 98.1%, respectively. Two large, randomized studies revealed anastrozole to cause objective response rates and stable disease comparable to what was achieved with megestrol acetate but with a lower incidence of side effects. While follow-up results have not revealed any significant difference in time to relapse between the drug regimens, they have revealed an improved survival among patients treated with anastrozole 1 mg compared to megestrol acetate 160 mg daily. Further follow-up is required to finally decide whether there may be a survival benefit also among patients treated with anastrozole 10 mg daily and to evaluate whether the improvement in survival is associated with an improved disease-free survival as would be anticipated.
Lønning
P E
PE
Department of Oncology, Haukeland University Hospital Bergen, Norway.
Geisler
J
J
Dowsett
M
M
D000077384:Anastrozole; D018931:Antineoplastic Agents, Hormonal / Q000493:pharmacokinetics / Q000494:pharmacology*; D047072:Aromatase Inhibitors; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D017326:Clinical Trials, Phase III as Topic; D004791:Enzyme Inhibitors / Q000493:pharmacokinetics / Q000494:pharmacology*; D006801:Humans; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy / Q000378:metabolism*; D009570:Nitriles / Q000493:pharmacokinetics / Q000494:pharmacology*; D017698:Postmenopause; D016032:Randomized Controlled Trials as Topic; D014230:Triazoles / Q000493:pharmacokinetics / Q000494:pharmacology*
D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D004791:Enzyme Inhibitors; D009570:Nitriles; D014230:Triazoles; D000077384:Anastrozole