Over the last few years, Thalidomide-Dexamethsone (TD) has been one of the most commonly used induction regimens for the treatment of newly diagnosed multiple myeloma (MM). In a phase III study conducted by the Italian Myeloma Network GIMEMA, TD was compared with Velcade-Thalidomide-Dexamethasone (VTD) as induction therapy in preparation for, and as consolidation after, melphalan (200 mg/m2)-based double autologous stem-cell transplantation (ASCT) in pts aged ≤65 years with symptomatic MM. Up-front VTD comprised Velcade, 1.3 mg/m2 on d 1, 4, 8, and 11; Dexamethasone, 40 mg on each day of and after Velcade administration; Thalidomide, 200 mg/d through d 1 to 63. Pts randomized to TD received Thalidomide as in VTD and Dexamethasone, 40 mg/d on d 1–4 and 9–12 of every cycle. Primary study end point was the rate of complete response (CR)/near CR (nCR) following three 21-d cycles of induction therapy. The study was started in May 2006 and was closed to accrual in April 2008, after a total of 480 pts were enrolled. Of these, 399 pts (199 randomized to VTD and 200 to TD) could be evaluated for primary study end point and toxicity of induction regimens (secondary end point). All analyses were intent to treat. In comparison with TD, VTD effected significantly higher rates of response (≥partial response: 78.5% vs 92%, P<0.001), including CR (6% vs 21%, P<0.001), CR+nCR (12% vs 33%, P<0.001) and ≥very good partial response (VGPR) (30% vs 61%, P<0.001). Remarkably, no pt treated on VTD had disease progression, as compared to 4.5% of pts on TD (P=0.002). Serious adverse events were recorded in 13.5% of pts randomized to VTD vs 12.5% of those assigned to TD. Although grade ≥3 peripheral neuropathy (PN) and skin rash (SR) were more frequent with VTD than TD (PN: 9% vs 2.5% of pts, P=0.005) (SR: 7.5% vs 1% of pts, P=0.001), only 4 pts in the VTD arm (2 in each of the two toxicity sub-groups) necessitated early treatment discontinuation. Overall, discontinuation of primary therapy due to treatment-related adverse events was required in 4.5% of pts on VTD vs 5% of those on TD, including a single pt in VTD and 2 pts in TD who died early. Eight additional pts randomized to TD discontinued induction therapy and went off study due to disease progression. Peripheral blood stem-cell (PBSC) harvest and response to first ASCT (secondary study end points) could be assessed in 297 pts (145 randomized to VTD and 152 to TD) for whom data were available at the time of analysis. Pts who achieved the minimum threshold dose of CD34+ cells to safely perform double ASCT (≥4×106/kg) were 91% in the VTD arm vs 87% in TD; median yields were 9.3 and 10.6 (×106 CD34+ cells/Kg), respectively. Pts who actually received the first ASCT were 89% (129/145) in VTD and 80% (121/152) in TD. On an intention-to-treat basis, the rates of high-quality responses in the VTD arm were significantly higher than in TD, including CR (41% vs 20%, P<0.001), CR+nCR (54% vs 29%, P<0.001) and ≥VGPR (75% vs 53%, P<0.001). After a median follow-up of 15 months, progression-free survival (PFS) was significantly superior with VTD as compared to TD (20-month estimate: 93% vs 86%, P=0.04), while the 20-month overall survival rate was 93% for both treatment groups. We conclude that, in comparison with TD, three 21-d cycles of VTD as primary therapy for newly diagnosed MM significantly increased the CR+nCR rates, up to values previously seen with one or two autotransplants preceded by conventional chemotherapy. Importantly, response benefit with up-front VTD vs TD translated into significantly higher CR+nCR rates after ASCT and significantly improved PFS. Effective combinations of novel induction agents, such as VTD, can, thus, have a remarkable impact on both pre and post-ASCT clinical outcome. Updated results, including response to second ASCT and consolidation therapy, will be presented at the meeting.

No abstract

In May 2006, the Italian Myeloma Network GIMEMA initiated a multicenter, randomized phase III study comparing VTD (arm A) with TD (arm B) incorporated into ASCT for newly diagnosed MM. Both VTD and TD were planned to be administered before (induction) and after (consolidation) double ASCT with melphalan 200 mg/m2 (MEL-200). In both arms, induction therapy consisted of three 21-d courses [63 days (d)]. The VTD regimen included Vel, 1.3 mg/m2 on d 1, 4, 8, and 11, plus Dex, 40 mg on each day of and after Vel administration; Thal was given at 200 mg/d from d 1 to 63. Patients randomized to TD received Thal as in arm A and Dex 40 mg/d on d 1–4 and 9–12 of every 21-d cycle. Primary study end point was complete response [either immunofixation negative (CR) or immunofixation positive (nCR)] to induction therapy. Secondary study end points included CR+nCR to consolidation therapy, time to progression, event-free survival, overall survival and toxicity. An interim analysis was planned to be performed after one year from study initiation to assess efficacy and toxicity of induction therapy. As of May 30, 2007, 234 patients entered the study and 187 were evaluated for response to induction therapy and adverse events (AEs). Of these patients, 92 were randomly assigned to receive VTD and 95 to receive TD. Efficacy and toxicity analyses were performed on an intention-to-treat basis. The rate of CR+nCR to VTD was 38% vs 7% to TD (P<0.001); 60% of patients in VTD arm and 25% of patients in the control group attained at least a very good partial response (P<0.001). Patients who failed at least a partial response to VTD were significantly less than those who failed on TD (7% vs 21%, respectively; P=0.004). Grade ≥ 2 and grade ≥ 3 AEs were similar in both arms, with the exception of grade ≥ 3 skin rash (6.5% in VTD arm vs 1% in TD arm; P=0.04). Grade 3 peripheral neuropathy was reported in 8% of patients randomly assigned to VTD and in 2% of patients treated with TD (P=0.07). All patients received acyclovir prophylaxis against reactivation of varicella zoster virus (VZV). VZV infection occurred in 2% of patients in VTD arm and in 1% of patients in the control group. Treatment discontinuation due to AEs was required in a single patient in each of the two treatment arms. No patient died for any cause during the induction phase. In a subgroup of patients with longer follow-up response to first ASCT was also evaluated. The rate of CR or CR+nCR to MEL-200 was significantly higher in VTD arm than in the control group (P=0.02 for CR comparison and P=0.05 for CR+nCR comparison between the two treatment arms). Preliminary analysis of this study provides demonstration that VTD is a highly active and well tolerated induction regimen, resulting in a significantly higher CR or CR+nCR rate compared to TD both before ASCT and after the first autologous transplantation with MEL-200.

42 We prospectively compared thalidomide-dexamethasone (TD) with bortezomib-thalidomide-dexamethasone (VTD) as induction therapy before, and consolidation after, double autologous stem-cell transplantation (ASCT) in patients with newly diagnosed multiple myeloma (MM). Three 21-d cycles of either VTD (V, 1.3 mg/m2 twice-weekly; T, 200 mg/d through d 1 to 63; D, 320 mg/cycle) or TD were given as induction therapy. Consolidation therapy comprised two 35-d cycles of VTD (V, 1.3 mg/m2 once-weekly; T, 100 mg/d through d 1 to 70; D, 320 mg/cycle) or TD. 474 patients randomized to the VTD (n=236) or TD (n=238) arm were analyzed on an intention-to-treat basis for response rate, PFS and OS. Centrally reassessed CR/nCR rate was significantly higher in the VTD compared with the TD arm after all treatment phases, including induction therapy (30% vs 10%, p<0.0001), double autotransplantation (54% vs 42%, p=0.008) and consolidation therapy (60% vs 44%, p=0.001). Best confirmed overall CR/nCR rate was 71% in the VTD arm compared with 52% in the TD arm (p<0.0001); the corresponding values for VGPR or better were 89% vs 72%, respectively (p<0.0001). To evaluate the role of consolidation therapy we performed a per-protocol analysis of 323 patients, 161 treated with VTD and 162 with TD. Overall, upgraded responses with VTD and TD as consolidation therapy were observed in 55% vs 37% of patients, respectively (p=0.01; OR:1.15-3.77). Furthermore, the probability to improve responses from less than CR before consolidation to CR after consolidation was 28% with VTD vs 15% with TD (p=0.02; OR:1.07-4.57) (p=0.003 using the Mc Nemar's test). Post-consolidation molecular detection of minimal residual disease was the objective of a substudy; detailed results are reported in a separate abstract. Briefly, both qualitative and quantitative analyses confirmed the statistically significant superiority of VTD over TD in effecting higher rates of molecular remissions and reducing the burden of residual myeloma cells after ASCT. Any grade 3–4 non-hematologic adverse events were 10% with VTD (peripheral neuropathy: 1.3%, skin rash: 0.6%) vs 12% with TD. With a median follow-up of 31 months, median PFS was 42 months in the TD arm and was not yet reached in the VTD arm (44-month projected rate: 61%) (HR: 0.62 [CI: 0.45–0.87], p=0.006). Superior PFS in the VTD vs TD arm was retained across patient subgroups with poor prognosis, including those with t(4;14) and/or del(17p). Randomization to VTD overcome the adverse influence of t(4;14) on PFS (40-month projected rates: 69% vs 67% according to the presence or absence of this abnormality, respectively; p=0.6). By the opposite, in the TD arm corresponding median PFS values were 24.5 vs 41.5 months, respectively (p=0.01). The small numbers of patients with del(17p) in both arms of the study precluded a statistical comparison with del(17p)-negative group. In a multivariate analysis, variables favorably influencing PFS were beta2-m lower than 3.5 mg/L (HR:0.47; p=0.000), absence of t(4;14) and/or del(17p) (HR:0.52; p=0.000), randomization to VTD arm (HR:0.57; p=0.002), attainment of at least VGPR (HR:0.50; p=0.009) and CR (HR:0.8; p=0.01). No statistically significant difference between the overall treatment protocols was seen in terms of OS, although curves seemed to initially diverge after 40 months (44-month projected rates: 84% vs 74% for VTD and TD arms, respectively). A multivariate analysis showed the independent role of absence of t(4;14) and/or del(17p) (HR:0.42; p=0.003), ISS stage1-2 (HR:0.49; p=0.02) and randomization to VTD (HR:0.53; p=0.04) in prolonging OS. When time-dependent CR entered the model, absence of t(4;14) and/or del(17p) and less advanced ISS stage retained their positive prognostic value; attainment of CR (strictly related to VTD randomization) was an additional favorable variable. In conclusion, in comparison with the TD arm of the study, 1) VTD induction emerges as a new standard of care for maximizing the degree and speedy of tumor reduction in preparation for ASCT; 2) VTD consolidation effected significantly higher rates of upgraded responses, including CR, and of molecular remissions; 3) double ASCT incorporating VTD as induction and consolidation therapy resulted in significantly longer PFS, a benefit confirmed in a multivariate regression analysis and maintained in the subgroup of patients with adverse cytogenetic abnormalities. Disclosures: Cavo: Janssen-Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium Pharmaceuticals: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Off Label Use: Use of bortezomib and thalidomide as induction therapy before, and consolidation after, autologous transplantation in newly diagnosed multiple myeloma. Baccarani:NOVARTIS: Honoraria; BRISTOL MYERS SQUIBB: Honoraria.

Over the last years, incorporation of novel agents into autologous stem cell transplantation (ASCT) has improved markedly the outcomes of younger patients with newly diagnosed multiple myeloma (MM). Superior results with experimental treatments vs previous standards of care have been frequently reported after preliminary analyses and need to be confirmed with longer follow up. The randomized phase 3 GIMEMA-MMY-3006 study was designed to compare bortezomib-thalidomide-dexamethasone (VTD) vs thalidomide-dexamethasone (TD) as induction therapy before, and consolidation after, double ASCT. Data from the initial analysis, with a median follow up of 36 months, demonstrated that patients randomized to the VTD arm enjoyed superior complete/near complete response (CR/nCR) rates after both induction and consolidation therapy, and had a significantly longer PFS compared to those prospectively assigned to the TD arm. We performed an updated analysis of the study after a median follow up of 59 months and results are herein reported. A persistent TTP and PFS benefit with incorporation of VTD into ASCT was confirmed. On an intention-to-treat analysis of 236 patients randomized to the VTD arm, median TTP was 62 months and median PFS was 57 months. The median values for 238 patients randomly assigned to the TD arm were 45 months for TTP (HR=0.64, p=0.001) and 42 months for PFS (HR=0.66, p=0.001) (Fig. 1). With the longer follow up of this analysis, an initial divergence between OS curves could be appreciated after 4 years, although the difference was not yet statistically significant at 6 years (75% for VTD vs 69% for TD). Superiority of VTD over TD for TTP and PFS was retained across prespecified subgroups of patients with high risk and low risk disease. In particular, PFS benefit with VTD was seen for patients age >60 years (HR=0.62, p=0.013) and younger than 60 years (HR=0.70, p=0.026), with ISS stage 1 (HR=0.59, p=0.009) and ISS stage 2-3 (HR=0.69, p=0.018), and for those with t(4;14) and/or del(17p) (HR=0.43, p<0.001) and with t(4;14) alone [t(4;14) positivity but lack of del(17p)] (HR=0.41, p=0.001). In comparison with patients with t(4;14) positivity who were randomized to TD, those assigned to the VTD arm had significantly longer PFS (median: 24 vs 53 months, HR=0.41, p=0.0007) (Fig. 2) and a trend towards longer OS (4-year estimates: 66% vs 81%, p=0.052). By the opposite, similar PFS curves were seen for patients in the VTD group regardless of the presence or absence of t(4;14) (Fig. 3). On multivariate Cox regression analysis, randomization to the VTD arm was an independent factor predicting for prolonged PFS (HR=0.64, P=0.001). Additional disease- and treatment-related variables independently affecting PFS included attainment of CR/nCR after both induction (HR=0.64, p=0.010) and consolidation therapy (HR=0.57, p<0.001), β2-m >3.5 mg/L (HR=1.7, p<0.001) and presence of t(4;14) and/or del(17p) (HR=2.0, p<0.001). On multivariate analysis, β2-m, cytogenetic abnormalities and attainment of CR/nCR after consolidation therapy were independently associated with OS. With an updated median follow-up of 49 months from the landmark of starting consolidation therapy, median PFS was 50 months for patients receiving VTD consolidation and 38 months for those treated with TD (HR= 0.69, P=0.015) (Fig. 4). Superior PFS with VTD vs TD consolidation therapy was observed for patients who failed CR/nCR after the second ASCT (HR=0.48, P=0.003) and was retained in both low risk and high risk subgroups. Finally, duration of OS from relapse or progression was similar between the two treatment groups (median, 42 for VTD vs 35 months for TD, p=0.47), even when bortezomib was incorporated into salvage therapy. In conclusion, this updated analysis of the GIMEMA-MMY-3006 study demonstrated: 1) a persistent PFS benefit with VTD vs TD in the overall population, as well as in subgroups of patients with high risk and low risk MM; 2) the ability of VTD, but not of TD, incorporated into double ASCT to overcome the adverse prognosis related to t(4;14); 3) the significant contribution of VTD consolidation to improved outcomes seen for patients randomized to the VTD arm; 4) the lack of more resistant relapse after exposure to VTD as induction and consolidation therapy compared to TD. A longer follow up is required to assess the OS benefit, if any, with VTD plus double ASCT. Disclosures: Cavo: Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Onyx: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Millennium: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees. Tacchetti:Janssen and Celgene: Honoraria. Zamagni:Celgene: Honoraria; Janssen-Cilag: Honoraria. Caravita:Celgene: Honoraria, Research Funding. Brioli:Celgene: Honoraria.