Consolidation Therapy Based on Conventional Chemotherapy and Corticoids Do Not Provide Therapeutic Advantage for Newly Diagnosed Patients after Autologous Transplantation.

Benefit of maintenance and/or consolidation therapy after autologous transplantation (AT) is unclear. CMG 2002 is randomized phase III study comparing efficacy and safety of consolidation therapy versus interferon alfa (IFN) maintenance therapy after AT in patients with newly diagnosed multiple myeloma (MM).

Methods: A total of 545 patients were enrolled to the trial in the period of April 2002 to April 2007. This first analysis (patients enrolled until December 31, 2005) was done in cohort of 269 patients randomly assigned after AT to either IFN 3x3 MU s.c. weekly alone (IFN group) until relapse or four cycles of chemotherapy CED (cyclophosphamide 300–400 mg/m² i.v., etoposide 30–40mg/m² i.v., and dexamethasone 40mg on days 1–4; month 4,8,12 and 16 after transplantation; CED group) followed by IFN 3x3 MU s.c. weekly starting month 18 after AT. All patients received primary therapy with four cycles of VAD regimen (vincristine, doxorubicine, and dexamethasone) followed by mobilization with cyclophosphamide 2.5g/m² and G-CSF 5–10 μg/kg. The conditioning regimen with melphalan 200mg/m² was used for single AT. Response was defined according to Blade’s criteria. Median of follow up is 41 months (range 6.2–56.1)

Results: All basic parameters including median age, gender distribution, measures of disease burden, renal function and also response rate before/after AT, and basic prognostic factors (beta2microglobulin, albumin, LDH, CRP) were comparable between randomized IFN group (n=134) and CED group (n=135) as follows: median age 57.0 vs. 57.0; stage I: 8.1% vs. 5.5%, stage II: 27% vs. 27.3%, stage III: 64.9% vs. 66.7%; stage B 12.8% vs. 17.1%; ISS I: 37.2% vs. 34.0%, ISS II: 29.7% vs. 34.0%, ISS III: 17.6% vs.21.8%, ISS not available: 15.5 vs.10.2%; IgA: 25.7% vs. 29.9%, IgG: 61.5% vs. 51.8%; ORR after AT (CR+PR): 72.3% vs.72.1%, CR: 23.0% vs. 19.0%, VGPR: 17.6 vs. 24.5%, PR 31.8% vs. 28.6%). Four cycles of CED consolidation treatment after AT did not significantly increase response rate achieved after AT in comparison with IFN group (response rate improved in 14,8% in CED group vs. 15,1% in IFN group at 4 months, respectively in 81,5% vs. 75,8% at 18 months after AT). There was no significant difference between CED and IFN groups in time to progression [TTP] (median 34.5 vs.38.2 months, p=0.622), in progression free survival [PFS] (median 32.4 vs. 36.8 months, p=0.515) and also in duration of response [DOR] (29.6 vs. 36.2 months). Median of overall survival was not yet reached (25th percentile 40.8 months for all patients). CED consolidation had acceptable toxic profile.

Conclusions: In the first analysis of CMG 2002 randomized phase III study consolidation therapy based on conventional chemotherapy and corticoids followed by IFN maintenance therapy did not show any benefit for patients if compared with IFN maintenance alone.