Femara (letrozole), a late-term hormonal therapy, has been approved as a treatment for breast cancer. Femara comes in 2.5 mg doses, recommended once daily.
In a randomized study, 18.4% of patients reported a complete or partial tumor response.
Common side effects reported include musculoskeletal pain (21%), nausea (13%), headache (9%), joint pain (8%), or fatigue (8%).
A second-line anti-estrogen therapy, the drug prevents the transformation of androgen compounds into estrogen by blocking the effects of the aromatase enzyme.