Klin Onkol 2002; 15(Suppl 2002): 21-27.
Summary: High-dose therapy (HDT) and autologous stem cell transplantation (ASCT) is superior than conventional therapy in response rates as well as in prolongation of event-free survival (EFS) and overall survival (OS) in multiple myeloma (MM). Optimal maintenance therapy after ASCT is unclear. In order to assess the role of interferon alfa (IFN) and IFN plus dexamethasone (IFN/DEX) as the maintenance therapy after ASCT, 212 previously untreated patients with multiple myeloma (MM) were enrolled to trial 4W from 1996 to 2002. Patients received primary therapy with four cycles of VAD regimen (vincristine, doxorubicin, dexamethasone) followed by mobilization with cyclophosphamide 5g/m2 and G-CSF 10 µg/kg. A conditioning regimen with melphalan 200mg/m2 was used for first and second transplantation. The later was indicated only in patients who did not achieve a good remission (>75% reduction of M-component). After transplantation patients were randomized to two arms of maintenance therapy: IFN 3 x 106 units three times weekly s.c. or the same dose of IFN in alternating cycles with dexamethasone 40 mg in days 1-4, 10-13, 20-23. Data of 151 randomized patients to 31st August 2001 were evaluated in this analysis. One month after transplantation 6 % of patients achieved complete remission (M-component 0% and negative immunofixation), 58 % remission (<75 % reduction of starting level of M-component), 24 % partial remission (<50 % reduction of M-component). Transplant related mortality at day +100 was 2.35 %. All 151 randomized patients received the maintenance therapy, 77 patients in the IFN arm and 74 patients in the IFN/DEX arm. Median of EFS for all 151 patients was 36 months and median of OS was not yet achieved. In this interim analysis, the OS and EFS curves have shown no significant differences between the IFN and IFN/DEX groups (p = 0.593 for EFS; p = 0.316 for OS). Longer follow-up is required to receive final results comparing efficacy of the two types of maintenance therapy after autologous transplantation.
