Randomized Phase II Trial of Doxil With or Without Dexamethasone for Metastatic Hormone Refractory Prostate Cancer

Primary Objectives: To assess the anti-tumor activity of Doxil by assessing response rates in patients with hormone refractory prostate cancer with or without dexamethasone pre-treatment. Secondary Objectives: To assess and estimate in patients with hormone refractory prostate cancer treated with Doxil with or without pre-treatment dexamethasone: 1) overall survival 2) toxicity, 3) quality of life parameters, 4) dose intensity administered in both treatment groups. Study Design: We will perform an open labeled, parallel, randomized phase II study using a two-stage design to determine if there is sufficient anti-tumor activity in either arm to warrant further study. Assumptions made in this study: an unacceptable overall response rate is \</= 10% and we will pursue further study if the overall response rate is \>/= 30%. The overall response rate for this study will be based on the total number of responses observed defined as: complete responses + partial responses (both by RECIST)+biochemical responses (in patients with no measurable target lesions a \>/= 50% decrease in PSA for \>/= 4 weeks). Fifteen patients will be randomized in the first phase (to both Arm 1 and Arm 2). No further patients will be accrued if \<2/15 responses are noted in a given arm. Ten additional patients will be enrolled if \>/= 2/15 responses are observed. If there are \>/= 5/25 responses then further studies will be pursued with that regimen. We will determine the overall incidence and severity of toxicities in both arms. Treatment: Arm 1: Doxil: Dose: 50 mg/m2, IV. Frequency: day 5 of each 28 day cycle. Arm 2: Doxil: Dose: 50 mg/m2, IV. Frequency: day 5 of each 28 day cycle. Arm 1 only: Dexamethasone: Dose: 12 mg bid po. Frequency: days 1,2,3,4,5 of each 28 day cycle. Number of Cycles for both Arm 1 and 2: until progression or unacceptable toxicity develops.