Two Doses of Conjugated Estrogen (Premarin) in Patients With Androgen-Independent Prostate Cancer

A Phase II Trial of Two Doses of Conjugated Estrogens (Premarin) in Patients With Androgen-Independent Prostate Cancer

Beth Israel Deaconess Medical Center, Massachusetts General Hospital, Brigham and Women's Hospital, Lowell General Hospital, South Shore Hospital, Emerson Hospital, Concord, MA, Saint Anne's Hospital

The purpose of this study is to see if Premarin is useful against androgen-independent prostate cancer and to help understand how drugs such as Premarin may work.

Patients will be randomly assigned to one of two study groups (arm A or Arm B). Arm A will receive 1.25mg of Premarin once daily and arm B will receive 1.25mg of Premarin three times a day. Patients will also receive coumadin daily to help prevent thromboembolic disease. After reviewing the first 30 patients on Arm A, it was determined that arm A (low dose Premarin) was not effective. Arm A was then closed and patients on Arm A were given the choice to switch to Arm B. Treatment will continue until there is evidence of disease progression or unacceptable side effects. Every 4 weeks while receiving Premarin, a physical exam and blood work will be performed. Every 12 weeks a CT scan of the abdomen and pelvis and a bone scan will be performed. Patients will also be encouraged to undergo standard preventative breast irradiation prior to starting Premarin or up to 4 weeks after starting treatment.

Group A: 1.25mg once a day Group B: 1.25mg three time a day Group A has been closed and participants have been given the option of enrolling in Group B. Treamtment can continue until disease progression or serious side effects.

To evaluate the efficacy of two different doses of Premarin in the treatment of patients with androgen-independent prostate cancer

Inclusion Criteria: Documented histologic evidence of prostate cancer. Progressive androgen-independent prostate cancer as defined by the Prostate-Specific Antigen (PSA) Working Group after conventional androgen deprivation and antiandrogen withdrawal. PSA > 2ng/ml and serum testosterone of < 50ng/ml No history of thromboembolic disease within the prior year ECOG performance status of 0-2 Creatinine < 2 x upper limit of normal Bilirubin < 2 x upper limit of normal AST < 2 x upper limit of normal Exclusion Criteria: Unstable angina or change in anginal symptoms within the past 6 months. Prior therapy with estrogens or PC-SPECS. Concurrent megestrol acetate or steroid hormones Major surgery or radiation therapy within 4 weeks Strontium-89 or samarium-153 therapy within 8 weeks