A phase I study of an outpatient regimen of recombinant human interleukin‐2 and alpha‐2a‐interferon in patients with solid tumors

Abstract

This study was undertaken to define the maximum tolerated dose (MTD) of recombinant interleukin‐2 (IL‐2) that could be combined with a fixed dose of alpha‐2a‐interferon (α‐IFN) in an outpatient setting. The schedule called for IL‐2 to be given by a 2‐hour intravenous infusion 5 days a week for 4 weeks. The α‐IFN was given at a dose of 6 × 106 U/m2/d intramuscularly 3 days per week (Monday, Wednesday, and Friday). The IL‐2 dose was escalated in four dose levels from 1 to 4 × 106 U/m2/d. The MTD in this study of 17 patients was at the fourth dose level of IL‐2 (4 × 106 U/m2/d). In addition to the usual IL‐2 toxicities, debilitating fatigue limited outpatient administration of this dose. Although the response rate was low, with partial responses seen in only 1 of 15 patients, 2 of 5 patients with melanoma treated at the higher dose levels had objective tumor shrinkage with one partial and one minor response. Thus, an IL‐2 dose of 3 × 106 U/m2/d combined with a recombinant α‐2a‐IFN dose of 6 × 106 U/m2/d is recommended for Phase II studies. Copyright © 1991 American Cancer Society