Abstract: Acute myeloid leukemia (AML) patients above the age of 60 or with secondary AML generally have an unfavourable outcome. The same is true for high risk myelodysplastic syndrome (MDS) patients ineligible to bone marrow transplantation. Indeed, in spite of an improved CR rate after intensive chemotherapy (about 60–65%), median CR duration and survival remain short (9–12 months in most studies), due to early relapses. (Sekeres MA et al.: Curr Opin Oncol2002;14:24–30. Verbeek W et al.: Ann Hematol2001;80:499–509). On the basis of our previous clinical trials with differentiative agents + low dose chemotherapy in MDS/AML patients unsuitable to intensive treatments, (Ferrero D et al.: Leuk Res1996;20:867–876; Haematologica2004;89:619–620), we adopted the same strategy as a post-remission maintenance therapy to patients with AML or MDS at high risk of relapse and ineligible to allogeneic transplant. Thirty-six patients (27 AML and 9 high risk MDS) who had obtained a CR after different schemes of intensive chemotherapy were scheduled to receive the maintenance treatment with 13-cis-retinoic acid (20–40 mg/day) + 1,25-di-hydroxy-vitamin D3 (1 microgram /day) in association to intermittent, low dose chemotherapy: 6-thioguanine 40 mg/day x 21 days every 5 weeks, alternated every 2–3 months, in 24 patients, to a 14 day course of ARA-C 8 mg/m2 s.c. x 2/day + 6-mercaptopurine 50 mg/day. Patients’ median age was 64 years (range 27–76), with only 9 below the age of 60. Cytogenetic analysis was performed successfully in 27 cases, and an unfavourable karyotype was found in 10. All patients presented at least one poor prognosis determinant, including age 〉 60 (27), previous AML relapse after autologous BMT (1), therapy-related disease (5), AML secondary to MDS (7), resistance to 1st induction therapy (4), hyperleukocytosis (8), RAEB-2 (8), abnormal karyotype (10). Twenty six had received 1 - 4 courses of consolidation treatment, including autologous stem cell transplantation in 2 MDS patients, before starting the maintenance program. Three patients underwent a very early relapse before maintenance start and 1 patient refused to prosecute the therapy after the first 2 months. The other 32 patients received the treatment as outpatients, with good tolerance and no major toxicity, until relapse, death or 4 years of continuous CR. After a median follow up for alive patients of 23 months (6–76), median disease-free (dfs) and overall survival, based on "intention to treat analysis" are 22 (1–74+) and 23 (5–76+) months, respectively, with a 28% 4 year actuarial survival. Inclusion of ARA-C in the maintenance treatment did not significantly prolong CR duration. The 17 patients with a normal karyotype enjoyed better median dfs (43 months) and overall survival (50,5 months) compared to the 10 patients with abnormal cytogenetics (12,5 and 15,5 months respectively); however, the differences are not significant, probably due to sample exiguity. In conclusion, our patients evidenced quite longer dfs and overall survival than expected from literature data on AML/MDS patients with similar features. However some late relapses (after 3–4 years) occurred. Therefore, our maintenance program seems worthy to be evaluated on larger casistics in randomised trials.

Abstract: Abstract 3029 Background. In a recent phase 3 trial, bortezomib–melphalan – prednisone–thalidomide followed by maintenance treatment with bortezomib–thalidomide (VMPT-VT) demonstrated superior efficacy compared with VMP. Peripheral neuropathy (PN) was the most important dose limiting toxicity. To decrease neurologic toxicities, the protocol was amended and patients in both arms received once-weekly instead of the initial twice-weekly bortezomib infusions. This post-hoc analysis assessed the impact of bortezomib dose-modification schedule on clinical outcomes and safety. Methods. Patients (N=511) older than 65 years were randomized to receive nine 6-week cycles of VMPT-VT (N=254; induction:V 1.3 mg/m2, d 1, 4, 8, 11, 22, 25, 29, 32, cycles 1–4, d 1, 8, 22, 29, cycles 5–9; M 9 mg/m2 d 1–4, P 60 mg/m2, d 1–4, T 50 mg d 1–42; maintenance: V 1.3 mg/m2 every 14 days and T 50 mg/day) or VMP (N=257) alone. In March 2007, the protocol was amended: both VMPT-VT and VMP induction schedules were changed to nine 5-week cycles and bortezomib schedule was modified to weekly administration (1.3 mg/m2 d 1,8,15,22, all cycles). Patients receiving VMPT-VT and VMP were pooled together and stratified according to the once-weekly or twice-weekly infusion modality; analyses were also conducted for patients receiving VMP only, to eliminate the influence of thalidomide and of maintenance on efficacy and safety. Results. Patients were evaluated in intention-to-treat: 372 patients received once-weekly and 139 twice-weekly bortezomib infusion. Patient characteristics were similar in the two groups, median age was 71 years. The efficacy data did not appear to be affected by the bortezomib schedule. Overall response rates were 85% with once weekly and 86% with twice- weekly schedule (P = .78), including CR rates of 30% and 35% (P = .27).Three-year PFS was 50% in the once-weekly and 47% in the twice-weekly group (P = 1.00), and 3-year OS was 88% and 89%, respectively (P = .54). Similar outcome was seen in the analyses restricted to VMP patients: CR rates were 23% with once-weekly and 27% with twice-weekly schedule (P = .54), 3-years PFS was 46% in once-weekly and 39% (P = .86) in twice-weekly group and 3-years OS was 87% and 89% (P = .47), respectively. The incidence of grade 3/4 hematologic toxicity was similar in the two groups (44% vs 45%, P = .83), but severe thrombocytopenia was slightly less common in the once-weekly patients (19% vs 26%, P = .08).The incidence of non-hematologic grade 3/4 adverse events was significantly reduced in the once-weekly: 35% vs 51% (P = .003). Grade 3/4 gastrointestinal events (6% vs 11%, P = .08), severe systemic events (4% vs 7%, P = .09) and grade 3/4 dermatologic events (2% vs 7%, P = .006) were less frequent in patients receiving once-weekly bortezomib. There was a significantly reduced overall incidence of grade 3/4 PN (8% vs 28%, P 〈 .001) in the once-weekly group. The median time to onset of grade 3/4 sensory PN was 4.3 months in the once-weekly group and 3.2 months in the twice-weekly group (P = .10). The cumulative incidence of sensory PN appeared to plateau after 12 months of therapy in both groups. Rates of discontinuations (5% versus 15%) and dose reductions (15% versus 41%) due to PN were also significantly lower in the once-weekly group (P 〈 .001). These results were reflected in analysis restricted to VMP patients, in which the incidence of grade 3/4 PN (7% vs 29%, P 〈 .001), the discontinuation rate (4% vs 16%, P = 0.002), and the dose reductions rate (15% vs 41% P 〈 0.001) were significantly lower in once-weekly group. Despite the cumulative planned dose being lower in the once-weekly group (46.8 vs 67.6 mg/m2), the delivered cumulative dose of bortezomib was similar in the two groups (39.4 mg/m2 vs 40.1 mg/m2). No association of PN with age or other baseline characteristics was outlined. The only significant factor influencing the incidence of PN was the reduction of bortezomib infusion from twice- to once-weekly (p 〈 0.001). Low dose thalidomide did not affect grade 3/4 PN rate (p=0.16). Conclusion. These results demonstrate that 1. both once-weekly and twice-weekly schedules in combination with MP ± thalidomide are highly effective in patients ≥ 65 years; 2. once-weekly schedule significantly reduced the incidence of PN and decreased the rate of discontinuation, resulting in similar cumulative bortezomib doses in the two groups; 3. the improvement in the safety profile was not associated with any reduction in the efficacy. Disclosures: Bringhen: Celgene: Honoraria; Janssen Cilag: Honoraria. Leoni:Celgene: Honoraria; Janssen Cilag: Honoraria. Patriarca:Celgene: Honoraria; Janssen Cilag: Honoraria; Roche: Honoraria; Merck: Membership on an entity's Board of Directors or advisory committees. Guglielmelli:Celgene: Honoraria; Janssen Cilag: Honoraria. Elice:Celgene: Honoraria; Novatis: Honoraria. Boccadoro:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Palumbo:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen-Cilag: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Abstract: In a recent phase 3 trial, bortezomib-melphalan-prednisone-thalidomide followed by maintenance treatment with bortezomib-thalidomide demonstrated superior efficacy compared with bortezomib-melphalan-prednisone. To decrease neurologic toxicities, the protocol was amended and patients in both arms received once-weekly instead of the initial twice-weekly bortezomib infusions: 372 patients received once-weekly and 139 twice-weekly bortezomib. In this post-hoc analysis we assessed the impact of the schedule change on clinical outcomes and safety. Long-term outcomes appeared similar: 3-year progression-free survival rate was 50% in the once-weekly and 47% in the twice-weekly group (P 〉 .999), and 3-year overall survival rate was 88% and 89%, respectively (P = .54). The complete response rate was 30% in the once-weekly and 35% in the twice-weekly group (P = .27). Nonhematologic grade 3/4 adverse events were reported in 35% of once-weekly patients and 51% of twice-weekly patients (P = .003). The incidence of grade 3/4 peripheral neuropathy was 8% in the once-weekly and 28% in the twice-weekly group (P 〈 .001); 5% of patients in the once-weekly and 15% in the twice-weekly group discontinued therapy because of peripheral neuropathy (P 〈 .001). This improvement in safety did not appear to affect efficacy. This study is registered at http://www.clinicaltrials.gov as NCT01063179.

Abstract: Introduction: The multicentre, randomized, open-label, phase 3 EMN02/HO95 study for patients with newly diagnosed multiple myeloma (NDMM) included two randomization stages (1:1) to (R1) intensification therapy with either upfront ASCT or bortezomib-melphalan-prednisone (VMP), and thereafter to (R2) consolidation therapy or no consolidation, followed by lenalidomide maintenance in both arms. Results of the final analysis from R1 (M. Cavo et al. Lancet Haematol. 2020, 7, e456-68) showed that at a median follow-up of 60.5 months progression-free survival (PFS), the primary study endpoint, was significantly improved with ASCT compared with VMP (median, 57 versus 42 months; HR 0.73, 95% CI 0.62-0.85, adjusted p=0.0001). However, no difference between these groups was found in terms of overall survival (OS), a secondary endpoint (HR 0·90, 0·71-1·13, adjusted p=0·35). Methods: We performed an updated analysis of the study with longer-term follow-up. Efficacy endpoints included OS, PFS on next-line therapy (PFS2), and time to next treatment (TTnT). Analyses were restricted to patients randomized to either ASCT (n=702) or VMP (n=495). Clinical outcomes of patients randomized to upfront ASCT or receiving ASCT at the time of progression after primary randomization to VMP (delayed ASCT) were also explored. Results: At an extended median follow-up of 75 months (IQR 67-84), patients randomized to ASCT had a significantly longer OS than those randomized to VMP (Figure). Median OS was not reached in both arms, and the 75-month survival estimate was 69% (95% CI 65-73) in the ASCT group versus 63% (95% CI 59-68) in the VMP group (HR 0.81, 95% CI 0.66-0-98, adjusted p=0.034). Patients who benefited the most from randomization to ASCT were those with unfavourable prognostic characteristics at baseline, including ISS disease stage 2-3 (HR 0.78, 95% CI 0.61-0.99, p=0.047), R-ISS stage 2-3 (HR 0.79, 95% CI 0.62-0.99, p=0.042), and the presence of at least one of the following cytogenetic abnormalities on FISH analysis: t(4;14) and/or t(14;16) in ≥10% CD138-positive plasma cells, and/or del(17p) in ≥20% enriched plasma cells. Overall, the 75-month OS estimate for patients with a high-risk cytogenetic profile was 54% with ASCT versus 39% with VMP (HR 0.61, 95% CI 0.42-0.89, p=0.010). The magnitude of OS benefit with ASCT, as measured by the HR value, was the highest for patients with del(17p) positivity (HR 0.49, 95% CI 0.28-0.86, p=0.013). PFS2 from R1 was significantly longer for patients in the ASCT arm than for those in the VMP arm. The 75-month PFS2 estimate was 57% in the ASCT group and it was 49% in the VMP group (HR 0.76, 95% CI 0.64-0.90, adjusted p=0.002) (Figure). Patients randomized to ASCT had a significantly longer TTnT in comparison with those who were randomly assigned to VMP. Median TTnT values for these groups were 66 versus 47 months, respectively (HR 0.71, 95% CI 0.60-0.82, adjusted p & lt;0.001) (Figure). Demographic and clinical characteristics at baseline of patients in the delayed ASCT group were comparable with those of patients who were randomized to upfront ASCT. PFS2 and TTnT in the upfront ASCT group were significantly longer than in the delayed ASCT group. Median PFS2 values were 85 versus 51 months, respectively (HR 0.52, 95% CI 0.40-0.66, p & lt;0.001). Median TTnT values were 59 versus 29 months, respectively (HR 0.32, 95% CI 0.26-0.40, adjusted p & lt;0.001). At the time that this analysis was performed, the rate of events of death was 30% in the upfront ASCT group versus 46% in the delayed ASCT group. In both the ASCT and VMP arms of the study, lenalidomide maintenance at the dose of 10 mg orally on day 1-21 of 28-day cycles was planned until progressive disease or undue toxicity. The median duration of lenalidomide treatment was 34 (IQR 13-63) months; 28% of patients were still on treatment at 60 months after start of lenalidomide and 31% discontinued due to treatment-related adverse events (27%) or second primary malignancies (4%). At a median follow-up of 70 (IQR 60-77) months from start of maintenance therapy, median PFS with lenalidomide was 56 months in the ASCT arm and 42 months in the VMP arm (HR 0.77, 95% CI 0.65-0.91, adjusted p=0.002). OS curves started to diverge at 5 years, and the 70-month estimate was 74% in the ASCT arm versus 69% in the VMP arm, suggesting that longer-term follow-up analysis is required. Conclusions: Upfront ASCT significantly prolonged OS, PFS2 and TTnT in comparison with VMP in NDMM patients. Figure Disclosures Cavo: Jannsen, BMS, Celgene, Sanofi, GlaxoSmithKline, Takeda, Amgen, Oncopeptides, AbbVie, Karyopharm, Adaptive: Consultancy, Honoraria. Gay:AbbVie: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive: Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees. Beksac:Janssen & janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Deva: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Dimopoulos:Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Research Funding, Speakers Bureau; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees. Petrucci:GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees. Zweegman:Amgen: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees; Janssen Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Zamagni:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Speakers Bureau; Takeda: Honoraria, Other: Travel, Accommodations, Expenses, Speakers Bureau; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Speakers Bureau; Celgene Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Speakers Bureau. Palumbo:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Galli:BMS: Honoraria; Celgene: Honoraria; Janssen: Honoraria; Takeda: Honoraria. Maisnar:Janssen, Takeda, Amgen, BMS/Celgene, The Binding Site: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Hansson:Amgen, Celgene, Takeda, Janssen Cilag: Consultancy. Belotti:Celgene: Membership on an entity's Board of Directors or advisory committees; Jannsen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Offidani:Janssen: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Zambello:Celgene: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees. Liberati:Verastem: Research Funding; Janssen: Honoraria, Research Funding; Takeda: Research Funding; Morphosys: Research Funding; Novartis: Research Funding; GSK: Research Funding; Incyte: Honoraria; Oncopeptides: Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Honoraria, Research Funding; Onconova: Research Funding; Pfizer: Research Funding; Karyopharm: Research Funding. Broyl:Janssen, Celgene, Takeda, Amgen: Honoraria. Musto:Amgen: Honoraria; Celgene: Honoraria. Ludwig:Seattle Genetics: Other: Advisory Boards; Takeda: Research Funding; Sanofi: Other: Advisory Boards, Speakers Bureau; Bristol Myers: Other: Advisory Boards, Speakers Bureau; Amgen: Other: Advisory Boards, Research Funding, Speakers Bureau; Janssen: Other: Advisory Boards, Speakers Bureau; Celgene: Speakers Bureau. Hajek:Roche: Consultancy, Honoraria, Research Funding; Oncopeptides: Consultancy, Honoraria, Research Funding; Pharma MAR: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Waage:Janssen: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy; Shire: Honoraria. Mellqvist:Janssen. Celgene, Amgen: Honoraria. Boccadoro:Novartis: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Mundipharma: Research Funding; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Research Funding; AbbVie: Honoraria; Bristol-Myers Squibb: Honoraria, Research Funding. Sonneveld:Karyopharm: Consultancy, Honoraria, Research Funding; Skyline Dx: Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy; Amgen: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding.

Abstract: In newly diagnosed multiple myeloma (MM) patients, the combination melphalan, prednisone and thalidomide (MPT) induces a fast tumor response with a high response rate, but evidence that this translate into improved outcome is limited. This multicenter trial compared the efficacy and the toxicity of oral MPT with oral melphalan and prednisone (MP) in previously untreated patients. From January 2002 to December 2004, we randomised 255 patients, who were older than 65 years of age (median age 72). Data analysis was performed on July 2005. The MPT regimen included oral melphalan (4 mg/m2 for 7 days) and prednisone (40 mg/m2 7 days) for six four week cycles plus thalidomide (100 mg per day continuously until any sign of relapse or progressive disease) The MP regimen was as MPT without thalidomide. Patients who were not assigned to receive thalidomide were permitted to cross over to receive thalidomide after relapse or disease progression. Patients treated with MPT experienced higher response rates and a longer time to progression (primary end points) than patients who did not receive thalidomide. The overall response rate was 76% for MPT and 48% for MP alone (P & lt;0.0001), and the near complete response rates were 28% and 7%, respectively (P & lt;0.0001). Median progression free survival in the MPT and in the MP groups was 33 months and 14 months, respectively (hazard ratio, 0.47; P & lt;0.001). MPT increase median progression free survival by almost 19 months. The 2-yr survival rate was 82% in MPT patients and 65% in MP patients (hazard ratio, 0.68; P=0.2). In MPT group, 33 patients did not complete the 6 courses because of progression disease (9), toxicity (16), death (2), and withdrawal of consent or lost to follow-up (6). In MP group, 32 patients did not complete the 6 courses because of progression disease (19), toxicity (3), death (3), and withdrawal of consent or lost to follow-up (7). By looking at those patients who completed the assigned 6 cycles in both arms, the 2-yr survival rate was 90% in MPT patients and 71% in MP patients, the difference was statistically significant (hazard ratio, 0.39; P & lt;0.01). Grade 3 or 4 adverse events were reported in 49% of patients treated with MPT and in 25% of those treated with MP: they included thromboembolism (12% versus 2% of patients), infections (10% versus 1%), peripheral neuropathy (10% versus 1%), and hematologic toxicity (22% versus 25%) respectively. In the first 64 patients who received MPT, grade 3–4 adverse events were reported in 58% of patients. In the last 65 MPT patients, the incidence of grade 3–4 adverse events was 40%. By comparing the first cohort with the second one, thromboembolism dropped from 22% to 3% (P & lt;0.01) and neurotoxicity from 13% to 8% (P=NS), respectively. The oral MPT was superior to the standard MP in patients with newly diagnosed myeloma. The adequate mangement of side effects reduced toxicity.

Abstract: Background. Autologous stem cell transplantation (ASCT) remains a gold standard treatment for younger patients with multiple myeloma (MM). With the aid of new drugs, the patients live longer and third salvage ASCT is an increasingly used option. However, the outcome of third salvage ASCT has not yet been analyzed. Methods. Between 1997 and 2010, 1288 MM patients who had received at least 3 ASCT were registered in the EBMT database. We excluded patients older than 75 years, those with a time from diagnosis to first ASCT of more than 10 years, patients transplanted with bone marrow, those with a time between relapse and ASCT of less than one month and those with an uncertain relapse date. Planned tandem ASCT was considered to be performed within a 6 month interval and at least 1 month apart. The conditioning regimen for the third transplant was high dosemelphalan alone or in combination withbusulfan orbortezomib. We could distinguish two main groups: 417 patients who received tandem ASCT and then a third ASCT after single relapse (AARA group) and 72 patients who received one ASCT, a second ASCT after first relapse, and a third ASCT after second relapse (ARARA group). A third group, who received tandem ASCT after relapsing following single ASCT comprised only 25 patients and was not studied. Results. We compared the two groups AARA vs ARARA. A third ASCT was performed in the AARA group in more recent years (p=0.047). There were more males than females (65% vs 72%) in both groups (p=NS). The main myeloma isotype was IgG (56% vs 58%). The ISS stage at diagnosis was similar (stage III in 70% vs 72% of cases). The time interval between diagnosis and first ASCT tended to be shorter in the AARA group (p=0.089), being within the first 6 months in 50% vs 38% of patients. The status at third ASCT was different: CR, 5% vs 4%: VGPR or PR, 45% vs 19%: MR or stable disease, 12% vs 15%: primary refractory/progressive disease, 38% vs 62% (p 〈 0.001). A Karnofsky score of 〉 70% at third ASCT was reported in 91% vs 90% of cases. The conditioning regimen at third ASCT was different between the two groups: melphalan 200 mg/m2, 42% vs 18%: melphalan 140 mg/m2, 6%vs 12%: other 52%vs 70% (p=0.018). The median age at third ASCT was 59vs 61 years. There was a trend to a longer time between first ASCT and first relapse (27vs 22 months (p=0.056)) in the AARA group while the interval between first ASCT and third ASCT was much shorter (44vs 64 months (p 〈 0.001)). The time between the last relapse and third ASCT was similar (9vs 11 months (p=0.4)). The median follow-up was similar (70vs73 months (p=0.9)). Engraftment was similar (96%vs93% (p=0.35)).The best response achieved after the third ASCT was superior in the AARA group: CR, 32%vs12%: VGPR or PR, 60%vs71% :MRor SD, 4%vs14%: progression, 4%vs3% (p 〈 0.001). The median OS after third ASCT was much higher in the AARA group: 30vs19 months (p=0.01) (Figure 1). The causes of death were: relapse/progression, 84%vs84%: second primary malignancies (SPM), 0.4%vs3.6%: other, 16%vs13%. There was a trend to more SPM including both hematologic and solid tumors in the ARARA group (p=0.068) with a shorter median time to SPM, 12vs42 months (p=0.004). Focusing on the AARA group, the longer the time from tandem ASCT to first relapse, the better the OS after the third transplant: if relapse occurred within 12 months of tandem ASCT, median OS of 13 months: within 18-24 months, OS of 29 months: within 36-60 months, OS of 59 months (Figure 2). Conclusions.A third ASCT is feasible in MM with more than 80% of patients achieving at least PR although with increased non relapse mortality. This treatment is mostly used in one of two scenarios: tandem ASCT followed by relapse and a third ASCT, or less commonly a first ASCT followed by a first relapse, a second ASCT, a second relapse and subsequently a third ASCT. The first scenario gives much better results, partly due to a better remission status at the third ASCT with no sign of increased SPM. In this AARA group, if relapse occurred more than 3 years after the initial tandem ASCT, the median OS after third ASCT was more than 4 years. These results should be compared with those obtained with the new drugs, especially in combination. Figure 1. AARAvsARARA groups: Overall Survival after the third transplant Figure 1. AARAvsARARA groups: Overall Survival after the third transplant Figure 2. AARA group: Overall Survival after the third transplant according to the time to relapse following tandem ASCT. Figure 2. AARA group: Overall Survival after the third transplant according to the time to relapse following tandem ASCT. Disclosures Garderet: Takeda: Consultancy; Amgen: Consultancy; BMS: Consultancy, Honoraria; Novartis: Consultancy. Dreger:Janssen: Consultancy; Gilead: Speakers Bureau; Novartis: Speakers Bureau; Novartis: Consultancy; Gilead: Consultancy; Roche: Consultancy. Leleu:TEVA: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria; LeoPharma: Honoraria; Pierre Fabre: Honoraria; Amgen: Honoraria; Bristol-Myers Squibb: Honoraria; Takeda: Honoraria; Celgene: Honoraria; Janssen: Honoraria. Peschel:MophoSys: Honoraria. Meuleman:Bristol-Myers-Squibb: Consultancy; Celgene: Consultancy; Amgen: Consultancy; Takeda: Consultancy. Ciceri:MolMed SpA: Consultancy. Schönland:Janssen, Prothena, GSK: Consultancy, Employment, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, accommations, Patents & Royalties, Research Funding, Speakers Bureau. Kröger:Sanofi: Honoraria, Research Funding; Neovii: Honoraria, Research Funding; Riemser: Honoraria, Research Funding; Novartis: Honoraria, Research Funding.

Abstract: Abstract 960 Background and aims: We have recently shown that multiple myeloma (MM) patients undergoing autologous transplantation (ASCT) followed by a consolidation with Bortezomib/Thalidomide/Dexamethasone (VTD) achieve molecular remission in 17% and major tumor shrinking assessed by real time-quantitative (RQ) PCR in the majority of cases (Ladetto et al, ASH Meeting 2008). However little is known on the minimal residual disease (MRD) kinetics occurring after such an extensive cytoreduction. In this study we have investigated the disease kinetics in the post-consolidation phase with the aim of identifying the RQ-PCR patterns associated with persistent remission or increased risk of relapse. Patients and methods: Inclusion criteria and consolidation treatment for this study have been already reported and included: 1) a documented complete or very good partial remission following ASCT delivered as first line treatment; 2) no previous treatment with thalidomide and bortezomib; 3) presence of a molecular marker based on the immunoglobulin heavy chain rearrangement (IgH-R). Consolidation consisted of four courses of: a) Bortezomib 1.6 mg/m2 on days 1, 8, 15, 22; b) Thalidomide at the initial dose of 50 mg/day with increments up to 200 mg; c) Dexamethasone 20 mg/day on days 1 to 4, 8 to 11 and 15 to 18. MRD was assessed on bone marrow samples at diagnosis, study entry, after two VTD courses, at the end of treatment and then at six months intervals. Qualitative and RQ-PCR analysis were carried out using IgH-R derived patient specific primers as already described (Voena et al, Leukemia 1997; Ladetto et al, Biol Bone Marrow Transpl 2000). MRD kinetics of relapsing vs non relapsing patients has been measured using observed marginal medians of ln RQ-PCR values. For the predictive value of MRD kinetics patients were defined as having low tumor burden (TB) if they reached after VTD a MRD level 〈 100 IgH-R/106 diploid genomes and as having active disease whenever a 10-fold tumor burden increase was recorded. Results: Feasibility, toxicity and clinical outcome of the trial have been already reported (Ladetto et al, ASH Meeting 2008). Thirty-nine patients were enrolled. Median follow-up from study entry is currently 32 months (50 from start of first line treatment). Following VTD, six patients achieved molecular remission (MR). Of these none has so far experienced a clinical relapse. MR was persistent in all patients, with an occasional PCR positive result in a patient who later reverted to PCR negativity. Among PCR positive patients 12 clinical relapses have been so far reported (50 months PFS: MR 100% vs no MR 62% - Figure 1A, p 〈 0.001). Figure 2 shows the kinetics of MRD overtime in relapsing vs not relapsing patients (p 〈 0.001), assessed on 230 RQ-PCR determinations at different timepoints. When RQ-PCR results of PCR positive patients were correlated with outcome we observed the following: 1) 14 patients achieved low TB and never had signs of active disease: none of them has so far relapsed except one who refused to undergo MRD monitoring and relapsed three year after the last PCR evaluation; 2) 13 patients never achieved a low TB and 8 of them relapsed; 3) 5 patients achieved a low TB but subsequently showed evidence of active disease: 3 of them relapsed. Patients in the first subgroup showed a 50 months PFS of 100% as opposed to those in group 2-3 who had a PFS of 37% (Figure 1B, p=0.001). Conclusions: Our results indicate that: 1) MRs following VTD are stable over time with no evidence of clinical and molecular relapse; 2) The vast majority of relapses occur in patients failing to achieve a low and stable TB; 3) Molecular monitoring of MRD allows to identify a large subset of patients (51% of cases) with an extremely low-risk of short-term relapse. Disclosures: Ladetto: CELGENE: Honoraria; JANSSEN-CILAG: Research Funding. Cavallo:CELGENE: Honoraria. Caravita:CELGENE: CONSULTANCY. Musto:JANSSEN-CILAG: Honoraria; CELGENE: Honoraria. Boccadoro:CELGENE: CONSULTANCY, ADIVISORY COMMITTEES, Research Funding; JANSSEN-CILAG: CONSULTANCY, ADIVISORY COMMITTEES, Research Funding; PHARMION: CONSULTANCY, ADIVISORY COMMITTEES, Research Funding. Palumbo:CELGENE: Honoraria; JANSSEN-CILAG: Honoraria.

Abstract: The extensive use of new drugs in multiple myeloma (MM) allowed the achievement of unprecedented levels of cytoreduction and major advantages in survival rates, though almost all patients still relapse after a successful treatment. PCR-based minimal residual disease (MRD) studies are powerful prognostic tools, able to indentify patients at high risk of relapse. Thus, there is a growing interest in MRD to modulate therapy also in MM, as already happens in other lymphoid neoplasms. However available reports have a too short follow-up to be conclusive. In particular some points need to be addressed: 1) which is the long-term outcome of patients achieving molecular remission (MR) in the absence of further treatment? 2) What is the prognostic impact of MR loss? 3) How long is the window between MR loss and clinical relapse? These issues have been addressed based on the mature results of the GIMEMA VEL-03-096 trial [EudraCT Number 2004-000531-28], which currently has a median follow-up (mFU) of 93 months. Patients and methods Inclusion criteria and treatment schedule have been already reported [Ladetto et al., J Clin Oncol 2010]. MRD was assessed on bone marrow at diagnosis, study entry, after two VTD courses, at the end of treatment and then every six months up to clinical relapse. Patients underwent MRD detection using both qualitative nested PCR and Real Time Quantitative (RQ)-PCR, employing immunoglobulin heavy chain-derived patient specific primers, as described [Voena et al., Leukemia 1997; Ladetto et al., Biol Bone Marrow Transpl 2000; van der Velden et al., Leukemia 2007] . MR was defined as negative MRD results by nested-PCR or less than 1EE-04 by RQ-PCR. Loss of MR was defined as an increase of MRD levels of at least one log in consecutive samples at whenever timepoint. For survival analysis duration of response (DOR), progression-free survival (PFS), time to next treatment (TNT) and overall survival (OS) rates were used, as detailed in IMWG criteria [Rajkumar et al., Blood 2011]. Results Thirty-nine patients were enrolled. So far 27 serological progressions, 22 clinical relapses needing salvage treatment and 12 deaths (two non-MM-related) were observed. Median PFS was 60 months, median TNT 67 months and OS at mFU was 64%. 270 of the planned samples for MRD monitoring (86%) were actually received by the centralized lab. Currently, 26 MR and 11 MR losses have been registered. The achievement of MR was strongly associated with a better outcome, in terms of median DOR (62 vs 9 months, p 〈 0.001), PFS (67 vs 22 months, p 〈 0.001), TNT (108 vs 30 months, p 〈 0.001) and resulted significant for OS, too (72% vs 48% at mFU, p=0.04, Figure 1A-B). Moreover, patients with ongoing MR, MR loss or not achieving MR at all showed increasing risk of relapse, respectively (DOR not reached vs 38 vs 9 months, PFS 92 vs 63 vs 22 months, TNT not reached vs 72 vs 30 months, each p 〈 0.001, Figure 2). Interestingly, the time lag between MR loss and clinical relapse for patients achieving and then loosing MR was comparable to that between end of consolidation and clinical relapse for patients never obtaining MR (TNT 19 vs 11 months p=0.34). Finally, analyzing the relationship between MR achievement, MR loss and need for a salvage treatment, of the 26 patients who obtained MR only 11 (42%) received a retreatment at a median time of 42 months (range: 22-87 months). Of these 11 clinical relapses, 7 were anticipated by a molecular relapse (64%), occurring at a median time of 9 months (range: 2-39 months). The 4 relapses not anticipated by MR loss occurred in cases with inadequate follow-up sampling or at least two years after the end of the planned molecular follow-up. Conclusions Besides confirming the strong prognostic value of PCR-based MRD monitoring in MM, our long-term results indicate the following: 1) the 42 months TNT of patients achieving MR underlines the excellent disease control of MM patients once obtained MR; 2) the occurrence of MR loss heralds relapse, with a TNT from MR loss comparable to TNT of patients not achieving MR; 3) there is a 9 months lag between MR loss and need for salvage treatment. These observations will have increasing relevance considering that ongoing methodological developments will allow effective MRD monitoring in the vast majority of MM patients. Disclosures: Off Label Use: Bortezomib and thalidomide as post-transplant consolidation during first-line treatment of multiple myeloma. Ladetto:Celgene: Research Funding, Speakers Bureau; Jannsen Cilag: Research Funding, Speakers Bureau; Mundipharma: Research Funding, Speakers Bureau; Roche: Research Funding, Speakers Bureau; Amgen: Research Funding, Speakers Bureau. Cavallo:Celgene: Consultancy, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Jannsen Cilag: Consultancy, Membership on an entity’s Board of Directors or advisory committees, Research Funding. Caravita:Celgene: Honoraria, Research Funding; Jannsen Cilag: Honoraria. Guglielmelli:Celgene: Research Funding. Boccadoro:Celgene: Consultancy, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Jannsen Cilag: Consultancy, Membership on an entity’s Board of Directors or advisory committees, Research Funding. Palumbo:Bristol-Myers Squibb: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Janssen Pharmaceuticals: Consultancy, Honoraria; Millenium: Consultancy, Honoraria; Onyx: Consultancy, Honoraria; Amgen: Consultancy, Honoraria.

Abstract: Abstract 1835 Poster Board I-861 Five studies demonstrated the superiority of MPT over MP regimen in elderly patients with MM not eligible for transplantation. In particular, one of these studies, showed this figure in patients aged more than 75 years who represent more than one third of MM patients. Nevertheless, in this latter study 42.5% of patients withdrawn from the MPT protocol because of toxicity. Therefore, there is a wide room of improving these results in this troublesome patient population. Using ThaDD regimen, including liposomal pegylated doxorubicin, we reported low haematological and non-hematological toxicity in elderly and