Anastrozole

Status

FDA-approved. FDA-approved labeling exists as Arimidex for adjuvant treatment and for advanced breast cancer in postmenopausal women. There is no approved indication in men. The label documents reductions in bone mineral density, increases in total cholesterol, joint symptoms and ischaemic cardiovascular events in patients with pre-existing disease.

What it is

An oral drug that lowers estrogen by blocking the aromatase enzyme.

What published research measured

A non-steroidal aromatase inhibitor that blocks conversion of androgens to oestrogens, with a large randomized trial base in breast cancer — the ATAC trial established superiority over tamoxifen in postmenopausal early breast cancer, and it has also been studied for risk reduction. Its use in men is off-label and the literature is much thinner: small trials in older men with low testosterone show it raises testosterone and lowers oestradiol as expected, but no outcome trial supports that use. The published concern that carries over directly is skeletal. Oestrogen is the principal regulator of bone density in men as well as women, and aromatase inhibition reduces bone mineral density and increases fracture risk in the cancer trials. Joint pain is the most common reason for discontinuation.

Source

ATAC trial · FDA labeling for Arimidex

Sources

• Half-life source for Anastrozole