Abstract: Carfilzomib is a novel generation proteasome inhibitor. The Carmysap trial demonstrated that twice-weekly KMP (carfilzomib, melphalan, prednisone) might challenge the MPV (melphalan, prednisone, bortezomib) standard. We sought to study KMP weekly, allowing to increase carfilzomib's dose with maintained efficacy and improved safety profile. Patients and Methods: IFM2012-03, a phase I multicenter study of KMP weekly in elderly patients with newly diagnosed multiple myeloma (eNDMM), aimed to determine the MTD of carfilzomib. Carfilzomib was given intravenously at 36, 45, 56, and 70 mg/m2/day on days 1, 8, 15, and 22 with melphalan and prednisone, for nine 35-day induction cycles, followed by carfilzomib maintenance for 1 year. Three dose-limiting toxicities (DLT) determined MTD at the lower dose. Results: Thirty eNDMMs were treated, 6 per cohort at 36, 45, and 56 mg/m2 and 12 at 70 mg/m². There was one DLT at 36 mg/m2 (lymphopenia), one at 45 mg/m2 (lysis syndrome), two at 56 mg/m2 (cardiac insufficiency and febrile neutropenia), and two at 70 mg/m2 (vomiting and elevated liver enzymes). The safety profile was acceptable; however, specific attention must be paid to the risk of cardiovascular events, especially for elderly patients. The overall response rate was 93.3%, with 46.6% complete response. Conclusions: The MTD dose of carfilzomib was 70 mg/m2 in this KMP weekly study in eNDMM. Response rates, and especially CR rate, were remarkable in this population, and would benefit from being assessed in a larger-scale study. The IFM2012-03 study demonstrated that the MTD of carfilzomib weekly is 70 mg/m2 in eNDMM, and 56 mg/m2 for patients older than 75 years. Carfilzomib used weekly in combination has a good efficacy and safety profile in eNDMM.

Abstract: Background. Progression by serum free light chain (sFLC) test without or preceding progression with intact immunoglobulin (Ig) is called light chain escape. This event alone is not considered a progression for patients with Multiple Myeloma (MM) according to International guidelines, although it is often considered a progression in real life and by clinical trials' investigators. We therefore sought to determine whether light chain escape would be a predictor of relapse and thus question a possible need to modify the current criteria for progression according to the International Myeloma Working Group (IMWG). Material and method. We have reviewed 325 (323 for analysis) patients that presented with a progression in the IFM/DFCI2009 phase 3 study (Attal et al. NEJM 2017). Among these 323 patients, 260 had initial tumor bulk measurement with intact Ig by serum protein electrophoresis test (SPEP; Ig ≥ 10 g/L) and 63 light chain MM (Ig 〈 10 g/L) measured using urine protein electrophoresis (UPEP). All progressions were validated in the central laboratory of CHU de Nantes (Dr T. Dejoie) and followed IMWG recommendations. sFLC increase was determined by absolute increase ≥ 100 mg/L and ≥ 25% from nadir value of the difference between involved and uninvolved FLC (ΔiFLC). Light chain escape was defined as sFLC increase without progression by SPEP (Ig increase ≥ 5 g/L and ≥ 25%) or UPEP (increase ≥ 200 mg/24h and ≥ 25%). Results. Among the 260 patients with intact Ig at diagnosis, 3 (1.15%) patients presented a light chain escape: progression by sFLC test without progression by SPEP. In parallel, 228 patients (87.7%) progressed by SPEP, of whom 18/228 (6.25%) showed a sFLC increase preceding the increase of intact Ig, with a median delay of 63 days. Among the 63 light chain MM, 6 (9.5%) patients presented a light chain escape: progression by sFLC test without progression by UPEP. Interestingly, 6 other patients (9.5%) progressed by SPEP even though Ig was 〈 10 g/L at diagnosis. Of the remaining 46 patients, 38 (60.3%) showed sFLC increase before progression by UPEP. Finally, 8 patients (12.7%) progressed but with intact Ig pauci-secreting MM meeting none of the M spike based progression criteria. Median time from iFLC nadir to ΔiFLC ≥ 100 mg/L was 280 days for light chain MM, 496 days for intact Ig MM, and 651 days for light chain escape. Median time from ΔiFLC ≥ 100 mg/L to follow-up visit to assess progression was 402 days light chain MM, 536 days for intact Ig MM, and 713 days for light chain escape. Overall, 9 (3%) patients had true light chain escape with progression by sFLC test without any other progression criteria. In parallel, in 56 (17%) patients, sFLC increase preceded progression to MM by standard test (SPEP or UPEP). Still the vast majority of patients had a regular relapse using the standard markers for progression. Conclusion. Based on a large study of patients treated into a phase 3 clinical trial with centralized assessment of response and progression, we showed that 20% of patients had progression by sFLC without meeting standard progression markers, of whom 3% had true light chain escape and 17% early light chain increase. Even though true light chain escape seems to be a rare phenomenon, analysis of sFLC test could help to avoid delayed or missed diagnosis of progression in 20% of patients in this clinical trial. This data should be confirmed in another database to assess whether a modification in the progression criteria in MM International guidelines should be proposed. Disclosures Hulin: Janssen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Roussel:Amgen: Consultancy; Celgene: Consultancy; Takeda: Consultancy. Hebraud:Amgen: Consultancy; Janssen: Consultancy, Other: Lecture fees; travel and accommodation for congress, Research Funding; Sanofi: Consultancy; Takeda: Consultancy; Celgene: Consultancy, Other: Lecture fees, Research Funding. Karlin: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, Other: travel support; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel support. Belhadj:Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Takeda: Consultancy, Honoraria. Decaux:Celgene: Honoraria; Janssen: Honoraria; Takeda: Honoraria; Amgen: Honoraria. Garderet:Amgen: Consultancy; Takeda: Consultancy; Celgene: Consultancy. Facon:Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Oncopeptides: Membership on an entity's Board of Directors or advisory committees. Avet-Loiseau:Abbvie: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, 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: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Moreau:Amgen: 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; Abbvie: 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; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees. Attal:Amgen: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Janseen: Consultancy, Research Funding; Sanofi: Consultancy. Leleu:Karyopharm: Honoraria; Gilead: Honoraria; Incyte: Honoraria, Other: steering committee membership ; Roche: Honoraria; Sanofi: Honoraria, Other: steering committee membership steering committee membership ; Novartis: Honoraria, Other: steering committee membership ; Amgen: Honoraria, Other: steering committee membership ; Merk: Honoraria, Other: steering committee membership ; Takeda: Honoraria, Other: steering committee membership ; BMS: Honoraria, Other: steering committee membership ; Celgene: Honoraria, Other: steering committee membership ; Janssen: Honoraria, Other.

Abstract: 8029 Background: Prolonged treatments have significantly improved survival in newly diagnosed multiple myeloma (NDMM). Lenalidomide (IMiDs), is currently approved in this indication, but remains a daily treatment, although oral, and may favor side effects in the long run. Furthermore, the use of a proteasome inhibitor (PI) is warranted in certain type of MM, such as high-risk. Carfilzomib, a second generation PI, has proved active combined with an acceptable security profile but its added benefit when given continuously is unknown. We thought to study maintenance Carfilzomib for elderly NDMM (eNDMM). Methods: The IFM 2012-03 multicenter phase I KMP (Carfilzomib, Melphalan, Prednisone) weekly study for eNDMM (≥ 65 years old) determined the maximal tolerated dose of weekly Carfilzomib at 70mg/m². We focus herein on the second part of the study with IV Carfilzomib monotherapy given at 36mg/m² for 13 cycles maintenance on an every 2 weeks schedule. Results: Thirty eNDMM were recruited in IFM 2012-03. Median age is 75, with 56% R-ISS 2 or 3 and 11% high-risk cytogenetic. With K weekly from 36 to 70mg/m², OS is reported at 93.3%, including 46.7% ≥CR; median PFS is 35.8 months and median OS was not reached. Twenty-two (73%) patients started K maintenance and 16 (73%) completed it. Four patients progressed and 2 stopped for AEs (renal amylosis, sensory neuropahty) during the maintenance phase. At maintenance completion, 50% were ≥CR. From the start of maintenance, in landmark analysis, median PFS is 28.1 months and the estimated 36-months OS approximately 70%. Conclusions: Carfilzomib monotherapy can be used safely in maintenance for 1 year in eNDMM, including for patients above 75 years. K maintenance may lead to deep response rate, certainly a most relevant prognostic factor for prolonged survival. Therefore, Carfilzomib maintenance, characterized with a simple administration modality, might be considered as an alternative to Lenalidomide and integrate the armamentarium of prolonged therapy in eNDMM. Clinical trial information: NCT02302495.

Abstract: Serum FLC analysis is a more sensitive indicator of disease than urinalysis. Improved sensitivity of serum over urine measurements during monitoring translates into valuable prognostic information.

Abstract: Purpose: Although the translocation t(4;14) is supposed to be a primary event in multiple myeloma, we have been surprised to observe that in large relapse series of patients, the t(4;14) can be observed only in subpopulations of plasma cells, in contrast to what is seen at diagnosis. This observation raised the question of possible subclones harboring the translocation that would be observable only at the time of relapse. Experimental Design: To address this issue, we analyzed by FISH a cohort of 306 patients for whom we had at least two samples obtained at different disease phases. Results: We observed a “gain” of the t(4;14) in 14 patients, and conversely, a “loss” of the translocation in 11 patients. Two hypotheses were raised: either an acquisition of the translocation during evolution or the existence of small t(4;14)-positive subclones at the time of diagnosis. To address this question, we had the opportunity to analyze two patients at the time of diagnosis by RT-PCR (reverse transcription-polymerase chain reaction) to look for the chimeric Eμ-MMSET transcript, and one patient positive at diagnosis, but negative at relapse. The samples were positive, supporting the second hypothesis. Furthermore, the IGH sequences of two patients who “lose” the t(4;14) were identical at diagnosis and relapse, confirming the existence of a common ancestral clone. Conclusion: Thus, the conclusion of this study is that the t(4;14) is not a primary event in multiple myeloma and that it can be present in silent subclones at diagnosis, but also at relapse. Clin Cancer Res; 19(17); 4634–7. ©2013 AACR.

Abstract: It is important to have an effective therapy for patients with multiple myeloma (MM) at first relapse, particularly if an autologous stem cell transplant (ASCT) is considered at this stage. This multicenter, phase 2 trial evaluated the efficacy and safety of weekly oral pomalidomide-cyclophosphamide-dexamethasone (PCD) in patients with MM in first relapse after treatment with lenalidomide-bortezomib-dexamethasone (RVD). All patients had received RVD as induction and consolidation therapy, plus lenalidomide maintenance for 1 year (arm A). Half had also received an ASCT after induction (arm B). At MM relapse, all patients received 4 oral cycles of pomalidomide 4 mg (days 1-21), cyclophosphamide 300 mg (days 1, 8, 15, and 22), and dexamethasone 40 mg (days 1-4 and days 15-18 of a 28-day cycle; PCD). Responding patients in arm A underwent ASCT and received 2 additional cycles of PCD, whereas those in arm B received 5 cycles of PCD. All patients received pomalidomide-dexamethasone maintenance until disease progression. Primary end point was partial remission or better after the initial 4 cycles of PCD. Responses were obtained in 82/97 (85%) patients evaluated: complete remission (n = 1; 1%), very good partial remission (n = 32; 33%), and partial remission (n = 49; 51%). Three patients (3%) had stable disease, and 6 (6%) had disease progression (6 response failures). Forty-five (94%) of the 48 patients in arm A underwent planned ASCT. PCD was effective therapy after first relapse with RVD. After 4 cycles, the rate of partial remission or better was 85%, and 94% of planned ASCTs were performed. Toxicity was mostly hematologic and manageable. This trial was registered at www.clinicaltrials.gov as #NCT02244125.

Abstract: High-dose melphalan (HDM) and transplantation are recommended for eligible patients with multiple myeloma. No other conditioning regimen has proven to be more effective and/or safer. We previously reported in a phase 2 study that bortezomib can safely and effectively be combined with HDM (Bor-HDM), with a 32% complete response (CR) rate after transplantation. These data supported a randomized phase 3 trial. Randomization was stratified according to risk and response to induction: 300 patients were enrolled, and 154 were allocated to the experimental arm (ie, arm A) with bortezomib (1 mg/m2 intravenously [IV]) on days −6, –3, +1, and +4 and melphalan (200 mg/m2 IV) on day –2. The control arm (ie, arm B) consisted of HDM alone (200 mg/m2 IV). There were no differences in stringent CR + CR rates at day 60 posttransplant (primary end point): 22.1% in arm A vs 20.5% in arm B (P = .844). There were also no differences in undetectable minimum residual disease rates: 41.3% vs 39.4% (P = .864). Median progression-free survival was 34.0 months for arm A vs 29.6 months for arm B (adjusted HR, 0.82; 95% CI, 0.61-1.13; P = .244). The estimated 3-year overall survival was 89.5% in both arms (hazard ratio, 1.28; 95% CI, 0.62-2.64; P = .374). Sixty-nine serious adverse events occurred in 18.7% of Bor-HDM–treated patients (vs 13.1% in HDM-treated patients). The proportion of grade 3/4 AEs was similar within the 2 groups (72.0% vs 73.1%), mainly (as expected) blood and gastrointestinal disorders; 4% of patients reported grade 3/4 or painful peripheral neuropathy in arm A (vs 1.5% in arm B). In this randomized phase 3 study, a conditioning regimen with Bor-HDM did not improve efficacy end points or outcomes compared with HDM alone. The original trial was registered at www.clinicaltrials.gov as #NCT02197221.