INTERFERON-ALPHA FOR INDUCTION AND MAINTENANCE IN MULTIPLE-MYELOMA - RESULTS OF 2 MULTICENTER RANDOMIZED TRIALS AND SUMMARY OF OTHER STUDIES

Background: Interferon (IFN) treatment trials in multiple myeloma have yielded discordant results regarding response rates, maintenance dura tion, and survival times. Further randomized trials and global evaluat ions of available data are urgently needed for clarification. Patients and methods: 256 patients participated in a randomized trial, 125 on IFN + VMCP, and 131 on VMCP alone. 100 patients were randomized to IFN maintenance (n=46) or were untreated controls (n=54). Global evaluati ons are based on 1,518 patients in induction and 924 in maintenance tr ials. Results: The induction trial demonstrated a significantly (p<0.0 5) lower rate of progressive disease under IFN + VMCP (10.6%) than und er VMCP (22.9%), but this benefit was limited to stage I or II patient s. Median progression-free survival was longer in the IFN + VMCP arm ( 23.2 months vs. 15.8 months); median overall survival did not differ s ignificantly (38.9 vs. 30.2 months). The IFN maintenance treatment tri al showed significantly superior results in the IFN arm versus control s (median maintenance duration: 17.8 months and 8.2 months (p<0.01), s urvival: 50.6 and 34.4 months (p<0.05), respectively). Previous IFN tr eatment increased the benefits of IFN maintenance therapy. Adverse eff ects of IFN during induction were hematologic toxicity, fever, and inf ections, requiring dose reductions. Toxic effects of IFN maintenance t reatment were mild. Global evaluations of randomized trials showed sma ll but significant benefits of combined IFN induction therapy and sign ificantly prolonged maintenance duration and survival under IFN mainte nance. Conclusions: Presently available data support the use of IFN ma intenance treatment because it significantly prolongs maintenance dura tion and survival. IFN added to induction chemotherapy resulted in min or improvements at the expense of increased toxicity, highlighting the need for better induction regimens.