Clinical Trial: The CAT Study: Atamestane Plus Toremifene Versus Letrozole in Advanced Breast Cancer

Study Status: Terminated
Recruit Status: Terminated
Study Type: Interventional

Official Title: Phase 3 Study of Atamestane Plus Toremifene Versus Letrozole in Advanced Breast Cancer

Brief Summary: The purpose of this study is to determine whether maximal estrogen suppression achieved via the combination of an experimental drug, atamestane, plus an FDA-approved drug, toremifene (Fareston®), is more effective than another approved drug, letrozole (Femara®), in delaying the growth of breast cancer, and whether the side effects of the combined hormonal therapy are different from the side effects of letrozole.

Detailed Summary: Aromatase is an enzyme expressed in tissues such as muscle and fat in postmenopausal women. These non-ovarian tissues become the dominant sources of estrogen in postmenopausal women. Breast cancer cells are often very dependent on estrogens to continue to grow. Atamestane blocks the formation of estrogens from androgenic precursors in the body via the aromatase enzyme. Toremifene blocks circulating and intracellular estrogens from stimulating estrogen receptors in breast cancer cells. The goal of therapy with atamestane, an aromatase inhibitor, in combination with the estrogen receptor antagonist, toremifene, is to achieve complete suppression of estrogen stimulation of breast cancer cells. This study is designed to determine whether combined hormonal therapy will lengthen the time to disease progression and the rate of objective response, as compared to single agent therapy with the approved aromatase inhibitor letrozole.
Sponsor: Intarcia Therapeutics

Current Primary Outcome: Time to progression

Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Response rate
  • Safety
  • Overall survival


Original Secondary Outcome: Same as current

Information By: Intarcia Therapeutics

Dates:
Date Received: November 22, 2004
Date Started: December 2004
Date Completion: August 2006
Last Updated: August 21, 2007
Last Verified: August 2007