Experience with interferon alpha 2b combined with dacarbazine in the treatment of metastatic malignant melanoma.

A prospectively randomized trial was undertaken to compare dacarbazine (DTIC) alone with DTIC plus interferon in patients with metastatic malignant melanoma. Of the 73 patients who entered on the study, 36 were randomized to receive DTIC alone and 37 were randomized to receive the combination DTIC plus interferon. The two sections were well balanced. There was more toxicity on the combination section, but no life threatening toxicity. The overall response rate for patients on DTIC was 20% (two complete and five partial responses) (95% CI 7-39%) and for patients on DTIC plus interferon was 50% (13 complete and four partial responses) (95% CI 26-72%) (p = 0.007). The median time to treatment failure, was significantly more in favour of the combination treatment (9 versus 2.5 months; p < 0.01, Mantel-Cox). The median survival of 16.7 versus 8 months was in favor of the combination treatment (p < 0.01). The reasons for the improved results with the combination treatment are discussed. The Eastern Cooperative Oncology Group is currently, based on the results of this study, investigating the role of interferon combinations in metastatic malignant melanoma.