Petrucci, Maria Teresa

Abstract Abstract 2877 Poster Board II-853 Background and Objective: In newly diagnosed multiple myeloma (MM) patients, treatment with lenalidomide plus high-dose dexamethasone (RD) was superior to high-dose dexamethasone in terms of both response rates and 1-year progression-free survival (PFS) (Zonder JA et al, Blood 2007;110:77). Preliminary results suggest that the combination lenalidomide plus low-dose dexamethasone (Rd) compared to the RD regimen yields significantly better 2-year overall survival (OS) (Rajkumar SV et al, J Clin Oncol 2008;26:8504). The combination of melphalan, prednisone, and lenalidomide (MPR) has been investigated in a phase I/II study showing promising results (Palumbo A et al, J Clin Oncol 2007; 25:4459-4465). The goal of this case –control study was to compare the efficacy and the toxicity of the lenalidomide/dexamethasone (len/dex) combination vs MPR as primary therapy for newly diagnosed elderly MM patients, to determine the additive value of melphalan compared to a regimen of lenalidomide plus corticosteroid. Patients and methods: Data from 51 newly diagnosed MM patients enrolled in Italy in a phase I/II dose-escalating trial, from January to October 2005, with MPR, were analyzed. For comparison of their outcome, 37 patients were identified among newly diagnosed patients seen at the Mayo Clinic from March 2005 to December 2008 who received len/dex as primary therapy and were enrolled in phase II or III trials. Patients treated with MPR received 9 monthly cycles of oral melphalan (doses ranging from 0.18 to 0.25 mg/kg on days 1-4), prednisone (2 mg/kg on days 1-4) and lenalidomide (doses ranging from 5 to 10 mg/day on days 1-21). After 9 cycles, patients started maintenance with lenalidomide alone (10 mg, days 1-21) until relapse or progression. Patients treated with len/dex received oral lenalidomide (25 mg/day, days 1-21) plus dexamethasone, either at low-dose (n=17) (40 mg orally days 1, 8, 15, 22) or at high-dose (n=21) (40 mg orally on days 1-4, 9-12, and 17-20). Treatment was continued until progression, relapse or unacceptable toxicity, or could be stopped at the physician's discretion. Patients (n=13) were allowed to receive transplant if they wished and were deemed eligible. Outcome was analyzed on an intention-to-treat basis. The Chi-square or the rank sum tests were used to compare variables. Time-to-event analysis was performed using the Kaplan-Meier method and comparisons were determined by the log-rank test and the Cox proportional hazards model. Results: On intention-to-treat analysis, 15.7% versus 23.7% patients, respectively in the MPR and in the len/dex group, (p=0.342) achieved a complete response, and 43.2% vs 47.4%, (p=0.691) achieved at least a very good partial response. Time-to-progression (TTP) (median: 24.7 vs 27.5 in MPR and len/dex groups, respectively; HR 1.04; 95% CI 0.55-1.98; p=0.903), PFS (median: 24.7 vs 27.5 in MPR and len/dex groups, respectively; HR 1.03; 95% CI 0.55-1.92; p=0.926) and OS (2-year OS: 86.2% in MPR group vs 89.1% in len/dex, HR 0.86; 95% CI 0.38-1.98; p=0.730) were not significantly different between the 2 groups. No significant differences in TTP, PFS and OS were reported when MPR patients were compared with the subgroup of patients treated with low-dose dexamethasone plus lenalidomide. Similar results were found when the analysis was restricted to MPR patients and len/dex pair mates receiving lenalidomide plus low/dose dexamethasone, matched according to age and sex, and who did not received transplant. The toxicity profile was different in the two groups. Hematologic grade 3-4 toxicities were more common with MPR compared with len/dex, in particular neutropenia (66.7% vs 21.1%, p < 0.001) and thrombocytopenia (31.4% vs 2.6%, p < 0.001), respectively. Grade 3-4 gastrointestinal events (13.2% vs 2.0%, p= 0.080), thrombotic events (13.2 vs 5.9, p= 0.279) and fatigue (10.5% vs 3.9%, p= 0.395) were more common with len/dex compared with MPR. Conclusion: Results of this case-control study show that both MPR and Rd are efficacious regimens for elderly MM patients. Data need however to be carefully evaluated and randomized control trials are needed to confirm these results. Disclosures: Off Label Use: research drug in combination to standard of care. Kumar:celgene: Research Funding; millenium: Research Funding; bayer: Research Funding; novartis: Research Funding; genzyme: Research Funding. Dispenzieri:celgene: Research Funding. Gertz:celgene: Honoraria; genzyme: Honoraria; millenium: Honoraria; amgen: Honoraria. Lacy:celgene: Research Funding. Musto:celgene: Honoraria. Fonseca:medtronic: Consultancy; genzyme: Consultancy; celgene: Consultancy; amgen: Consultancy; BMS: Consultancy; otsuka: Consultancy. Petrucci:celgene: Honoraria; Janssen Cilag: Honoraria. Greipp:celgene: Research Funding. Boccadoro:jansen Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; pharmion: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Palumbo:Janssen-Cilag: Honoraria; Celgene: Honoraria.

Abstract Background: Bortezomib (VELCADE®) is a first-in-class, reversible proteasome inhibitor with activity in multiple myeloma (MM) and other malignancies. Bortezomib showed significant activity in previous phase 2 and 3 studies in patients (pts) with previously treated MM. This international multicenter open-label phase 3b study allowed expanded access to bortezomib therapy in pts with relapsed/refractory MM treated with ≥ 2 previous lines of therapy. Methods: Pts with MM were eligible if they had received ≥ 2 prior lines of therapy and required treatment due to relapsed or progressive disease. Pts with grade ≥ 2 peripheral neuropathy (PN) were excluded. Pts received 1.3 mg/m2 IV bolus bortezomib on days 1, 4, 8, and 11 of each 3-week cycle for up to 8 cycles; dexamethasone (20 mg/d PO on the day of and day after bortezomib dose) could be added after cycle 2 for progressive disease or after cycle 4 for stable disease. Adverse events (AEs) were assessed beginning at the start of treatment and continuing until 30–42 days after treatment and were graded based on NCI-CTC version 2.0. Efficacy assessment was performed based on changes in disease burden as measured by monoclonal (M)-protein concentration in serum and urine every 2 cycles (6 weeks). Response was assessed using modified SWOG criteria: complete response (CR) was a 100% reduction in M-protein; very good partial response (VGPR), 75–99% reduction; partial response (PR), 50–74% reduction; minimal response (MR), 25–49% reduction; and stable disease, < 25% reduction. Increasing M-protein levels indicated progressive disease. Results: 624 pts in 93 centers from 21 countries received at least 1 dose of treatment and were evaluable for safety (55.3% male; median age 62.7 years). 68% of pts received 3–11 lines of previous therapy. Karnofsky performance status was ≤70 in 25.6% of pts; 141 pts (22.6%) were ≥ 70 years of age. Pts completed a median of 5 cycles of therapy (range 0–13); 39.3% of pts completed all 8 planned cycles. Grade 3/4 treatment-emergent (related and unrelated) AEs were reported in 430 pts (68.9%), with thrombocytopenia (29.2%), neutropenia (13.3%), and anemia (11.7%) the most common hematologic AEs. Grade 3/4 PN was reported in 8.2% of pts. Overall, 165 pts (26.4%) discontinued therapy due to treatment-related AEs. Best responses among evaluable pts (n = 593) included 12.0% CR, 23.1% VGPR, 19.1% PR, and 16.5% MR, for an overall response rate of 70.7%. Median time to first response was 42 days (range 7–125), and median time to best response was 63 days (range 7–235). Conclusions: Bortezomib 1.3 mg/m2 administered biweekly q3 weeks was well tolerated with manageable toxicities in pts with relapsed and/or refractory MM. Response rates with bortezomib were high, even in heavily pretreated pts, inducing > 25% CR/VGPR. This study confirms results from initial clinical trials in a broader population.