Trial Information

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

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.