Purpose: Phase II and III studies have shown that the addition of interleukin-2 (IL-2) and interferon alpha-2b (IFN alpha-2b) in multiagent chemotherapy (CT) for advanced melanoma increases overall response (OR), albeit without clear evidence of an improvement in overall survival (OS). Treatment with high-dose IL-2 can cause severe toxicity and is normally administered in an inpatient setting. We conducted a multicenter prospective randomized clinical trial in outpatients with metastatic melanoma to compare CT with biochemotherapy (bioCT) using immunomodulant doses of IL-2 and IFN alpha-2b.
Patients and methods: One hundred seventy-six eligible patients with advanced melanoma were randomized to receive CT (cisplatin and dacarbazine with or without carmustine every 21 days) or bioCT comprising the same CT regimen followed by low-dose subcutaneous IL-2 for 8 days and IFN alpha-2b three times a week, both for six cycles.
Results: At a median follow-up of 18 (CT) and 16 (bioCT) months, median OS was 9.5 versus 11.0 months (P =.51), respectively. In the 89 CT-arm patients, 18 ORs (20.2%) (three complete responders [CRs] and 15 partial responders [PRs]) were observed according to World Health Organization criteria. In the 87 bioCT-arm patients, 22 ORs (25.3%) (three CRs and 19 PRs) (P =.70) were recorded. Treatment-related toxicity was fairly similar in both arms.
Conclusion: The addition of low-dose immunotherapy did not produce a statistically significant advantage in OS, time to progression, or OR. However, the 11-month median OS in the bioCT arm does not differ greatly from the best results with high-dose IL-2-containing regimens reported in the literature. Furthermore, our treatment schedule was carried out on outpatients and had an acceptable level of toxicity.