CLINICAL-EXPERIENCE WITH THE COMBINED USE OF RECOMBINANT INTERLEUKIN-2(IL2) AND INTERFERON ALFA-2A(IFN-ALPHA) IN METASTATIC MELANOMA

A multicentre study of IL2 and IFN-alpha has been performed in 58 patients with metastatic melanoma. The scheme consisted of IL2 3.0 BRMP MU/m2/d as a continuous infusion for 4 d combined with subcutaneous administration of IFN-alpha 6 MU/m2/d, day 1 + 4. The cycle was repeated every 2 weeks for a maximum duration of 26 weeks. 54 patients were evaluable for response. One (2%) achieved a complete and 10 (19%) a partial response. 19 (35%) patients were stable and 24 (44%) showed progressive disease. Common side-effects included fever, chills, fatigue, skin rash, anorexia, nausea and diarrhoea. Hypothyroidism was noted in 10% of the patients. These results show that this regimen of IL2 and IFN-alpha is active but, in contrast to what could be expected, not superior to IL2 alone possibly due to suboptimal dosing. In an ongoing study in Rotterdam and Nijmegen, a more intense schedule was chosen, consisting of three daily i.v. doses of IL2 4.5 BRMP MU/m2 and IFN-alpha 3.0 MU/m2 for 5 d. This regimen is repeated at intervals of 3 weeks for a total of three cycles. Presently, nine patients have been entered. One patient achieved a complete response, four a partial response (overall 56%), three had stable disease and one progressed. Toxicity was severe and treatment was prematurely stopped in five patients: myocardial infarction (one patient), atrial fibrillation (one patient), negative T waves and myocardial hypokinesia (one patient) and psychosis (two patients). This regimen can only be justified if the therapeutic results are superb, which has yet to be awaited.