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Researchers Continue Enrollment For National Breast Cancer Prevention Trial (dateline August 2, 2000)


Over 6,000 women at high risk of breast cancer have already enrolled in the STAR clinical trial ,  and researchers are hoping that another 16,000 women will join within the next few years.  The STAR (Study of Tamoxifen and Raloxifene) clinical trial is a national trial run by the National Surgical Adjuvant Breast and Bowel Project (NSABP). STAR is designed to determine whether the drug raloxifene (brand name, Evista) is as effective as the drug tamoxifen (brand name, Nolvadex) in preventing breast cancer.

Tamoxifen, an antiestrogen, has recently been approved by the U.S. Food and Drug Administration (FDA) for women at high risk of developing breast cancer. Research prior to FDA approval showed that tamoxifen can reduce the chances of developing breast cancer by 49% in women at high risk.  Raloxifene, also an anti-estrogen, is FDA approved to help treat and prevent osteoporosis, a degenerative bone disease. Early research has shown that raloxifene may help prevent breast cancer and could have fewer side effects than tamoxifen.

Side effects of tamoxifen may include:

  • Hot flashes
  • Vaginal dryness
  • Unusual vaginal discharge or bleeding
  • Irritation of skin around the vagina

Tamoxifen also increases a woman's chances of developing serious health problems including:

  • Endometrial cancer (cancer of the lining of the uterus)
  • Deep vein thrombosis (blood clots in large veins, particularly in the legs)
  • Pulmonary embolism (blood clot in the lung)
  • Possibly stroke

The STAR trial began one year ago, and recruitment will continue for up to four more years.  STAR is a randomized, double-blind study that will include 22,000 post-menopausal women (age 35 or older) who are at increased risk for developing breast cancer as determined by their age, family history of breast cancer, personal medical history (such as a diagnosis of lobular carcinoma in situ ), age at first menstrual period, and age at first childbirth.  

Candidates must go through a process known as informed consent, during which they learn about the potential benefits and risks of tamoxifen and raloxifene before deciding whether to participate in STAR. The women who choose to enroll are randomly assigned to a regimen of either 20 milligrams of tamoxifen or 60 milligrams of raloxifene daily for five years. All participants will receive close follow-up examinations, including mammography and physician performed clinical breast exams on a regular basis for at least seven years.  Women who participate in STAR will not be charged for the cost of either tamoxifen or raloxifene.  

More than 500 centers in the United States, Canada, and Puerto Rico are enrolling women in STAR. Click here for additional information on eligibility requirements and how to enroll in STAR.

Additional Resources and References