Exemestane in Preventing Cancer in Postmenopausal Women at Increased Risk of Developing Breast Cancer

• Frequency of Serious Adverse Events [ Time Frame: 5 years ] [ Designated as safety issue: Yes ]
  Frequency of serious adverse events for women who choose to receive 5 years of exemestane as preventative therapy.
• Invasive Breast Cancer Incidence (Breast Cancer-Free Survival) [ Time Frame: Over study (median follow-up 35 months) ] [ Designated as safety issue: No ]
  Invasive breast cancer incidence was estimated from the breast cancer-free survival (BCFS) which was calculated for all women from the day of the randomization to the earliest date of diagnosis for invasive breast cancer. Women who died from other causes were censored at the time of death. If a woman did not develop an invasive breast cancer, or died, BCFS was censored on the date of the last day the woman was known alive (LKA), which was the latest of the date of assessment. Women who had breast cancer before study entry were also censored at the time of randomization.

• Total Incidence of Invasive and Non-invasive (DCIS) Breast Cancer [ Time Frame: Over study (median follow-up 35 months) ] [ Designated as safety issue: No ]
  It was estimated from the Total Breast Cancer-Free Survival (TBCFS), which was calculated for women who developed invasive or non-invasive (DCIS) breast cancer as the time from the date of randomization to the earliest date of diagnosis for invasive or non-invasive (DCIS) breast cancer. Women who died from other causes were censored at the time of death. Women who had breast cancer before entry were censored at the time of randomization. If a woman did not develop an invasive or non-invasive (DCIS) breast cancer, or died, TBCFS will be censored on the date of last known alive.
• Incidence of Lobular Carcinoma in Situ, Atypical Ductal Hyperplasia and Atypical Lobular Hyperplasia Events [ Time Frame: Over study (median follow-up 35 months) ] [ Designated as safety issue: No ]
• Number of Clinical Breast Biopsies [ Time Frame: Over study (median follow-up 35 months) ] [ Designated as safety issue: Yes ]
• Incidence of All Clinical Fractures [ Time Frame: During protocol treatment (up to 5 years) ] [ Designated as safety issue: Yes ]
• Incidence of Clinically Relevant Cardiac Events [ Time Frame: During protocol treatment (up to 5 years) ] [ Designated as safety issue: Yes ]
  Events including myocardial infarctions and angina requiring percutaneous transluminal coronary angioplasty or coronary artery bypass graft, fatal and nonfatal strokes and all vascular deaths
• Incidences of Other Malignancies [ Time Frame: Over study (median follow-up 35 months) ] [ Designated as safety issue: Yes ]
  Other malignancies includes any other malignancy which is not in breast.

RATIONALE: The MAP.3 study was designed to test whether hormone therapy using exemestane may prevent breast cancer by blocking the production of estrogen. This study was analyzed in April 2011 and showed a 65% reduction in the incidence of invasive breast cancer in women receiving exemestane compared to women on placebo.

PURPOSE: The study protocol was amended in May 2011 and the current purpose of the study is to allow all study participants the opportunity to complete 5 years of exemestane.

OBJECTIVES:

Primary

Previously: To determine if exemestane reduces the incidence of invasive breast cancer compared with placebo.

Currently: To determine the frequency of serious adverse events for post-menopausal women at high-risk of developing breast cancer who choose to receive 5 years of exemestane as preventative therapy.

Secondary

Previously: (same as is currently listed in PDQ) Currently: To address the Trial Committee and Sponsor's commitment to allow women who are randomized to the MAP.3 trial to receive 5 years of exemestane therapy.

OUTLINE: This study was a randomized, double-blind, placebo-controlled, multicentre study. Protocol-specified analyses were performed in April 2011. The results of these analyses are posted in the Results section. Following the amendment of May 2011, the study is now open-label and all eligible patients are receiving exemestane from participating sites for a total of 5 years. After exemestane is stopped, there is no further follow-up.

PROJECTED ACCRUAL:There were 4560 women from the United States, Canada, Spain and France who took part in this study.

• Goss PE, Richardson H, Chlebowski R, Johnston D, Sarto GE, Maunsell E, Ingle JN, Alés-Martinez JE. National Cancer Institute of Canada Clinical Trials Group MAP.3 Trial: evaluation of exemestane to prevent breast cancer in postmenopausal women. Clin Breast Cancer. 2007 Dec;7(11):895-900. No abstract available.
• Moy B, Richardson H, Johnston D, et al.: NCIC CTG MAP.3: enrollment and study drug adherence of ethnic minority women in a breast cancer prevention trial. [Abstract] Breast Cancer Res Treat 106 (1): A-3048, S141-2, 2007.
• Richardson H, Johnston D, Goss PE, et al.: Participant characteristics on an international NCIC CTG breast cancer prevention trial. [Abstract] J Clin Oncol 25 (Suppl 18): A-1531, 2007.
• Goss PE, Ingle JN, Alés-Martinez J, Cheung A, Chlebowski RT, Wactawski-Wende J, McTiernan A, Robbins J, Johnson K, Martin L, Winquist E, Sarto G, Garber JE, Fabian CJ, Pujol P, Maunsell E, Farmer P, Gelmon KA, Tu D, Richardson H. Exemestane for primary prevention of breast cancer in postmenopausal women: NCIC CTG MAP.3 - A randomized placebo-controlled clinical trial. J Clin Oncol 29[suppl; abstr LBA504], 2011.
• Richardson H, Johnston D, Pater J, Goss P. The National Cancer Institute of Canada Clinical Trials Group MAP.3 trial: an international breast cancer prevention trial. Curr Oncol. 2007 Jun;14(3):89-96.
• Goss PE, Ingle JN, Alés-Martínez JE, Cheung AM, Chlebowski RT, Wactawski-Wende J, McTiernan A, Robbins J, Johnson KC, Martin LW, Winquist E, Sarto GE, Garber JE, Fabian CJ, Pujol P, Maunsell E, Farmer P, Gelmon KA, Tu D, Richardson H; NCIC CTG MAP.3 Study Investigators. Exemestane for breast-cancer prevention in postmenopausal women. N Engl J Med. 2011 Jun 23;364(25):2381-91. Epub 2011 Jun 4.

• At increased risk of developing breast cancer, due to at least one of the following risk factors:

  • Gail score ≥ 1.66
  • Age ≥ 60 years
  • Prior atypical ductal hyperplasia, lobular hyperplasia, or lobular carcinoma in situ on breast biopsy
  • Prior ductal carcinoma in situ (DCIS) treated with total mastectomy with or without tamoxifen (tamoxifen must have been completed ≥ 3 months prior to randomization)
• No prior DCIS treated with lumpectomy with or without radiation
• No prior invasive breast cancer
• Not BRCA1 or BRCA2 carriers

PATIENT CHARACTERISTICS:

Previous:

• 35 and over
• Female

• Postmenopausal, defined as one of the following:

  • over 50 years of age with no spontaneous menses for at least 12 months before study entry
  • 50 years of age or under with no menses (spontaneous or secondary to hysterectomy) for at least 12 months before study entry AND with follicle-stimulating hormone level within postmenopausal range
  • Underwent prior bilateral oophorectomy
• No other malignancies within the past 5 years except adequately treated nonmelanoma skin cancer, curatively treated carcinoma in situ of the cervix, or other curatively treated solid tumors with no evidence of disease for ≥ 5 years
• No uncontrolled hypothyroidism or hyperthyroidism
• No major medical or psychiatric illness (including substance and alcohol abuse within the past 2 years) that would preclude study participation or compliance
• Must be accessible for treatment and follow-up
• Willing to complete quality of life questionnaires in either English or French

Current: MAP.3 participants who were randomized to the exemestane arm, are currently receiving exemestane as part of the MAP.3 study and who have not completed 5 years of exemestane.

OR MAP.3 study participants who were randomized to the placebo arm and who have either completed 5 years of study drug or who are still receiving placebo. Note: this applies only to centres that choose to allow placebo "cross-over".

PRIOR CONCURRENT THERAPY:

Previous:

• More than 3 months since prior and no concurrent hormone replacement therapies
• More than 3 months since systemic estrogenic, androgenic, or progestational agents

• More than 3 months since prior and no concurrent hormonal therapies, including, but not limited to the following:

  • Luteinizing-hormone releasing-hormone analogs (e.g., goserelin or leuprolide)
  • Progestogens (e.g., megestrol)
  • Prolactin inhibitors (e.g., bromocriptine)
  • Antiandrogens (e.g., cyproterone acetate)
  • Selective estrogen-receptor modulators (e.g., tamoxifen, toremifene, or raloxifene)
• No investigational drug within 30 days or 5 half lives prior to randomization
• No concurrent endocrine therapy
• No concurrent estrogens, androgens, or progesterones
• Concurrent low dose (≤ 100 mg/day) prophylactic aspirin allowed
• Concurrent bisphosphonates for prevention or treatment of osteoporosis allowed
• No other concurrent medications that may have an effect on study endpoints

Current: There are no prior concurrent therapy restrictions for the amended MAP.3 study.

• Grupo Espanol de Investigacion del Cancer de Mama
• UNICANCER