Abiraterone Acetate for Castrate Resistant Prostate Cancer

Study Summary

This research study is a Pilot clinical trial. Pilot clinical trials often examine new tests (such as laboratory or radiology tests) in patients who receive either standard cancer treatments or new treatments that have been well-tested in many patients on other trials. It is often difficult to determine how prostate cancer is going to behave when a new treatment is started. Physicians have no way to predict how a patient's tumor will respond to treatment. Although scientists have learned about changes that happen in tumors due to treatment, it is difficult to get cells from tumors because a biopsy (surgical procedure to remove a small piece of tissue) is needed. This study will evaluate a method to detect tumor cells that are circulating in the blood without getting a biopsy. It is known that tumors shed a small number of cells into the blood stream every day. These are called circulating tumor cells or CTCs. Some early studies indicate the amount and type of CTCs in the blood can help determine the status of the tumor itself and the way it is responding to treatment. In this study, the investigators will examine protein levels in CTCs from patients' blood at different times before and after drug treatment to determine if they correlate with response to the drug. The new test will not affect whether subjects continue on the study drug. Abiraterone acetate is a marketed drug that has been studied for the treatment of metastatic CRPC. It blocks the remaining or residual male hormones in the body that may be helping prostate cancer to grow. Abiraterone acetate is now FDA-approved for patients with metastatic CRPC who have not yet received docetaxel chemotherapy. Abiraterone acetate has been used by a large number of participants in previous clinical trials. In most of these trials, participants with CRPC have been given abiraterone acetate with prednisone. Prednisone is a man-made hormone commonly referred to as a steroid. Prednisone has been approved in the US, Ca

Primary Outcome

To assess AR signaling in CTCs and correlate with PSA response and/or measurable disease response, if applicable. The investigators have developed a protein-based test to evaluate whether the AR signal is active ("AR-on") or inactive ("AR-off") or indeterminate ("AR-mixed"). The investigators will examine the AR signaling present in CTCs prior to and during abiraterone therapy. By correlating the baseline or post-treatment change in AR signaling with other measures of clinical benefit, the inves

Interventions

• DRUG Prednisone
• DRUG Abiraterone