Temozolomide plus pegylated interferon alfa-2b as first-line treatment for stage IV melanoma: a multicenter phase II trial of the dermatologic cooperative oncology group (DeCOG)

BACKGROUND: Combination of temozolomide (TMZ) with nonpegylated interferon alfa is associated with increased efficacy in terms of response rates compared with monotherapy. A multicenter phase II study was carried out to assess the activity and toxicity of TMZ plus pegylated interferon alfa-2b (peg-IFNalpha-2b), hypothesizing improved efficacy due to modified pharmacokinetic properties of the novel interferon (IFN) formulation. PATIENTS AND METHODS: In all, 124 patients with stage IV melanoma without prior chemotherapy and no cerebral metastases were treated with 100 mug peg-IFNalpha-2b s.c. per week and oral TMZ 200 mg/m(2) (days 1-5, every 28 days). Primary study end point was objective response, and secondary end points were overall and progression-free survival (PFS) and safety. RESULTS: In all, 116 patients were assessable for response: 2 (1.7%) had a complete response and 19 (16.4%) a partial response (overall response rate 18.1%). Of total, 25.0% achieved disease stabilization and 56.9% progressed. Overall survival was 9.4 months; PFS was 2.8 months. Grade 3/4 thrombocytopenia occurred in 20.7% and grade 3/4 leukopenia in 23.3%. CONCLUSIONS: The efficacy of TMZ plus peg-IFNalpha-2b in this large phase II study is moderate and comparable to published results of the combination of TMZ with non-peg-IFN. Likewise, the safety profile of peg-IFNalpha-2b seems to be similar to non-peg-IFN when combined with TMZ.