I posted this on the AR board a month back, and thought I might as well post it here too.
This was an article about the powerful Femara as an aromatase inhibitor:
Femara Effective In Postmenopausal Women With Advanced Breast Cancer
EAST HANOVER, NJ -- February 5, 1998 -- Clinical data published in this month’s Journal of Clinical Oncology show Novartis Pharmaceuticals Corp.’s Femara(TM) (letrozole tablets, USP) 2.5 mg once-a-day therapy to be an effective treatment of advanced breast cancer in postmenopausal women with disease progression following antiestrogen therapy.
The study was an international double-blind trial of 551 advanced breast cancer patients. These patients were randomised to one of three treatment arms: 0.5 mg Femara, 2.5 mg Femara or 160 mg of megestrol acetate (MA). The study showed that 2.5 mg Femara once daily to be effective and generally well-tolerated in postmenopausal women with disease progression following antiestrogen therapy (for example, tamoxifen).
"In the advanced disease setting when antiestrogen therapy fails, it is vital to have additional treatment options," said David Parkinson, MD, vice president of clinical research at Novartis Pharmaceuticals. "These data demonstrate that Femara may be an effective option to help shrink tumours or slow the progression of the disease in postmenopausal women for whom antiestrogen therapy has failed."
In the study, an objective (complete or partial) response to treatment was demonstrated in approximately 24% of those receiving Femara 2.5 mg and in approximately 16% of those receiving megestrol acetate. The study also showed that the median duration of response had not been reached with Femara 2.5 mg; the median duration of response for megestrol acetate had been reached at 18 months.
This trial showed that Femara was generally well tolerated. The most common adverse effects with 2.5 mg Femara were musculoskeletal pain, nausea, headache, arthralgia (joint pain), fatigue, vomiting, and dyspnea (breathing difficulty).
Typically in treating breast cancer, hormone therapies such as antiestrogens and aromatase inhibitors may be used to block actions of hormones, such as estrogen, that stimulate the growth of hormone-dependent cancer cells. Antiestrogens, such as tamoxifen, block estrogen from stimulating cancer cells by binding to estrogen receptors in the cancer cells.
Rather than blocking estrogen from reaching the estrogen receptor sites in cancer cells, aromatase inhibitors reduce the amount of estrogen circulating in the body. As an aromatase inhibitor Femara binds to the enzyme aromatase and inhibits it from converting a precursor hormone -- androstenedione -- to estrogen in tissues, such as fat, liver and muscle.
Women whose disease cannot be controlled by antiestrogen therapy may be switched to other hormone therapies, including aromatase inhibitors. In postmenopausal women, the aromatase pathway is the primary source of estrogen production. According to a recent report, nearly 120,000 U.S. women are living with advanced breast cancer. Of these women, the majority are postmenopausal (over the age of 50).
Also, two studies done recently has shown that femara is more effective as an anti-estrogen than arimidex or nolvadex.
Geisler J, Anker G, Dowsett M, Lonning PE.
Letrozole suppresses plasma estrogen levels in postmenopausal breast cancer patients more completely than anastrozole. Presented at the 36th Annual Meeting of the American Society of Clinical Oncology (ASCO), May 20-23, 2000, New Orleans, Louisiana. Abstract 394.
Mouridsen H, Gershanovich M, Sun Y, et al.
Superior efficacy of letrozole (Femara ®) versus tamoxifen as first-line therapy for postmenopausal women with advanced breast cancer: results of a phase III study of the international Letrozole Breast Cancer Group. J Clin Oncol. 2001; 19(10):2596-2606.
I hope this info is useful to you, StoneColdGold.
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