Purpose: Combination of capecitabine and interferon has shown activity in metastatic renal cell carcinoma. Pegylated interferons might have more clinical activity and fewer side effects. This study evaluated the efficacy, tolerability, and safety of the combination of capecitabine and pegylated interferon alfa-2a.
Methods: In this open label, single institution, non-randomized phase-II first-line study, 26 patients were included. Capecitabine was administered 2,000 mg/m(2) daily for 14 days followed by 1 week rest. Pegylated interferon alfa-2a was given once as weekly injections with a fixed dose of 180 microg. Overall survival, progression-free survival, and response rates were evaluated; safety and tolerability were monitored.
Results: Response rate was 27, with 4% complete responses. Stable disease was achieved in 42%. The treatment discontinued in 4 (15%) patients before first response evaluation because of toxicity. The median progression-free survival was 7.5 months; the median overall survival was 17 months. Grades 3-4 toxicity was seen in 46% of patients, but in 93% of cycles no serious toxicity was experienced. Dose reductions had to be done, but in 81% of cycles intensity of 70% or more was possible. Quality of life was better in cycle five than in the base line.
Conclusions: The combination had moderate, but manageable toxicity. In the future studies, lower dose for capecitabine is recommended. The combination was active and the response rates seen here were in line with phase-II studies on former combinations of non-pegylated interferons. One complete remission was achieved.