5-fluorouracil and allopurinol combined with recombinant interferon-alpha 2b in the treatment of patients with advanced prostate cancer: a phase I/II study.

Abstract

We determined the toxicity and preliminary response rate of escalating doses of 5-fluorouracil (670 to 1,500 mg./m.2 per day) combined with a fixed dose of interferon-alpha 2b (5 million units) and allopurinol (300 mg. every 8 hours) in cohorts of patients with metastatic prostate cancer. The trial included 11 men with metastatic prostate cancer. Cohorts of patients received a 5-day constant infusion of 5-fluorouracil combined with subcutaneous interferon-alpha 2b 3 times weekly and allopurinol for 1 week during 5-fluorouracil infusion. Treatment was repeat every 3 weeks. Of 10 patients evaluable for treatment response and toxicity 3 had a partial response as judged by significant decreases in prostate specific antigen measurements (mean followup 13.5 months). Significant dose limiting toxicities encountered included mucositis, diarrhea and leukoneutropenia. Further evaluation of this treatment to determine overall response rates and benefit should take into consideration the significant toxicity experienced.