Combination of fibroblast interferon (HuIFN beta), carboxamide (DTIC), and cimetidine for advanced malignant melanoma.

In vitro synergism between interferons (IFNs) and chemotherapeutic drugs has been demonstrated, and an enhancement of IFN's antiproliferative effects when combined with cimetidine has been suggested in melanoma patients. In this pilot study, 12 patients with advanced malignant melanoma received HuIFN beta by 30 min i.v. infusion at 30 X 10(6) u/m2 day for 4 days, followed by i.v. decarbazine (DTIC) 1.0 g/m2 on day 5, repeated every 4 weeks. Oral cimetidine, 300 mg q.i.d., was given continuously. All the patients had visceral (bulky) metastases. No objective responses were observed; however, two patients had stable diseases for 16 and 20 weeks, respectively. Mild chills and fever with IFN, and mild to moderate emesis with DTIC, were noted. No additive haemopoietic or hepatic toxicity was observed. Combination of HuIFN beta, DTIC, and cimetidine is relatively nontoxic, but does not appear to have a significant antitumor activity in patients with advanced malignant melanoma.