The FDA has approved elacestrant (Orserdu – Stemline), an oral estrogen receptor antagonist, for treatment of estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer in postmenopausal women or men who had disease progression following endocrine therapy. Elacestrant is the first oral selective estrogen receptor degrader (SERD) to be approved for treatment of breast cancer; the injectable SERD fulvestrant (Faslodex, and generics) was approved more than 20 years ago.

Interim results of a double-blind, placebo-controlled trial suggest that off-label use of the anticholinergic drug oxybutynin may reduce the frequency and severity of hot flashes in women with breast cancer. Extended-release oral oxybutynin (Ditropan XL, and generics) has been shown to reduce the frequency and severity of hot flashes in healthy menopausal women.

Infertility occurs in about 15% of couples. About one-third of cases are due to problems with ovulation or other female factors, another third are due to a male infertility factor, and the remaining third are unexplained. In older women, unexplained infertility is probably caused by diminished quality and quantity of oocytes. The first approach to treatment of female-factor infertility generally is the use of drugs that stimulate oocyte production.

Adjuvant hormone therapy with anti-estrogen drugs has been shown to reduce disease recurrence and mortality in postmenopausal women with estrogen receptor (ER)-positive breast cancer. In recent years, aromatase inhibitors (AI) have become the preferred first-line hormonal treatment over tamoxifen for such patients.1,2

A randomized, placebo-controlled, double-blind trial of exemestane (Aromasin, and others) in postmenopausal women considered at increased risk for breast cancer found that the aromatase inhibitor, over a median follow-up of 35 months, significantly decreased the annual incidence of invasive breast cancer from 0.55% to 0.19% (PE Goss et al. N Engl J Med, epub June 4, 2011).

In addition to surgery and radiation therapy, a variety of drugs are used both singly and in combination to treat breast cancer. This article summarizes the principles of adjuvant therapy and treatment for metastatic disease. A summary of individual drugs and their adverse effects begins on page 3.

Anastrozole (Arimidex - AstraZeneca, Medical Letter 1996; 38:61), an aromatase inhibitor, has received accelerated approval from the FDA for adjuvant treatment of postmenopausal women with early hormone-receptor-positive breast cancer. The drug was approved for treatment of postmenopausal women with metastatic breast cancer in 1996.

Fulvestrant (Faslodex -- AstraZeneca), an estrogen receptor antagonist given intramuscularly (IM) once a month, was recently approved by the FDA for treatment of hormone-receptor-positive metastatic breast cancer in postmenopausal women with disease progession on tamoxifen (Nolvadex, and others) or another antiestrogen.

The FDA has approved exemestane, an aromatase inhibitor, for the treatment of postmenopausal women with advanced breast cancer that has progressed during treatment with tamoxifen.