A RANDOMIZED TRIAL OF MAINTENANCE INTERFERON FOLLOWING A HIGH-DOSE CHEMOTHERAPY IN MULTIPLE-MYELOMA - LONG-TERM FOLLOW-UP RESULTS

High-dose chemotherapy (melphalan) with autologous marrow stem cell su pport (AMSCS) results in high response rates in multiple myeloma (MM), with up to 50% of patients achieving complete remission, However, the se remissions are generally not durable, As the cytokine interferon al pha has been shown to prolong partial response following conventional chemotherapy, this trial was conducted to evaluate its role following high-dose chemotherapy, 85 patients were randomly assigned to maintena nce treatment with interferon alpha, 3x10(6) units/m(2) subcutaneously three times weekly until relapse or no further treatment following re covery from high-dose chemotherapy (melphalan 140-200mg/m(2) or busulp han 16 mg/kg) combined with AMSCS, At 5.8 years following the accrual of the last patient in this trial, 38 patients had died, 17 in the int erferon arm and 21 in the control arm. The median progression-free sur vival (PFS) in the 42 patients randomized to interferon alpha was 46 m onths versus 27 months in the controls. Both overall survival and PFS, which were highly significant at median follow-up of 52 months, have now ceased tc, be significant, because most patients have ultimately s uccumbed to their disease, Interferon was tolerated by the majority of patients with very good compliance. Toxicity consisted mainly of flu- like symptoms and malaise which were usually self-limiting. The result s of such a pilot study should be carefully interpreted and the benefi ts of interferon should be confirmed in larger multicentre studies in the setting of minimal residual disease following autologous transplan tation.