Abstract: Abstract 428 Lenalidomide (R) has significant activity in patients with multiple myeloma (MM). R has also shown activity in patients with AL amyloidosis, especially in combination with dexamethasone (D). However, AL patients are usually frail and R at the standard dose of 25 mg/day has been associated with significant toxicity. In MM patients, R with low dose D (Rd) has a better toxicity profile than the combination of R with high dose D. Alkylating agents, such as cyclophosphamide (C), are active in patients with AL and combinations of R with alkylating agents have given promising results in patients with MM. Thus, we designed a phase I/II trial of R, with low dose D and low dose C (RdC) in patients with AL. Primary objective of the study was to determine the maximum tolerated dose (MTD) for RdC and to assess hematologic response. Patients receive D 20 mg on days 1-4 (total 80 mg per cycle) , C on days 1-10, R on days 1-21 every 28 days, according to dose level (level 0: R 10 mg, C 50 mg, level 1: R 10 mg, C 100 mg, level 2: R 15 mg, C 100 mg). In the phase I part of the study, patients were observed for 2 cycles for determination of Dose Limiting Toxicity (DLT) according to a standard 3+3 design. Patients with a creatinine ≤2.5 mg/dL and adequate hepatic function were enrolled. All patients receive low-dose aspirin or LMWH if indicated. So far 23 patients have been enrolled in the study (16 in phase I, 7 in phase II). In the phase I study, 3 patients were enrolled in dose level 0, 7 in dose level 1 and 6 in dose level 2. Dose level 2, (R 15 mg, C 100 mg) is being further explored; 7 patients have been enrolled in phase II and accrual is ongoing. So far, 132 cycles of therapy have been administered; 8 patients have receive ≥6 cycles of RdC and 3 have completed 12 cycles of treatment. According to consensus criteria, heart was involved in 65%, kidneys in 61%, liver in 9% and 17% had AL-related peripheral neuropathy; 95% of the patients were Mayo stage II or III. Most patients (70%) were previously untreated. Among 7 pretreated patients, 2 had refractory disease, 2 had prior thalidomide and 5 had prior bortezomib. Hematologic response rates for patients who received at least 2 cycles of treatment, among all cohorts, was 64% and for the patients treated at dose level 2 was 75%. Median time to hematologic response was 2.5 months (range 0.9-4.8 months) for all patients and 1 month (range 0.9-2.9) for those treated at dose level 2. Organ responses have been recorded in 5 patients so far (3 cardiac and 3 renal responses, 1 patient had both cardiac and renal response). After a median follow-up of 7 months, 7 patients have died; 5 due to progressive heart amyloid, one patient had an acute MI followed by acute stent thrombosis and one died due to sepsis. The most common hematologic toxicities were anemia (grade 3/4 in 17%) and neutropenia (grade 3/4 in 17%). Most common non-hematologic toxicities were infection (grade ≥3 in 22%), fatigue (grade ≥3 in 9%), and rash (in 22%, grade 3 in 4%); also one patient suffered a stroke and one had DVT while on treatment with RdC. In parallel, and on a compassionate basis, AL patients with creatinine 〉 2.5 mg/dL or on dialysis, were offered RdC with R dose adjusted according to CrCl. Initially R was given 15 mg every other day for CrCl 〈 30 ml/min, or 15 mg thrice per week on the day after dialysis but due to toxicity R dose was reduced to 10 mg. So far, 13 patients have been treated with attenuated-dose RdC: 3 patients achieved a CR, one achieved a cardiac and one patient a liver response. However, the non-hematologic toxicity of the combination in patients with renal impairment was significant including fatigue (53%), infections (38%), rash (31%), diarrhea (15%), hyponatriemia (15%). Three patients discontinued treatment due to toxicity after the 1st cycle (including one early death due to non-neutropenic infection). In conclusion, RdC is an effective oral regimen for patients with AL amyloidosis, inducing significant rates of hematologic and organ responses. The recommended dose for RdC was R at dose of 15 mg, C at a dose of 100 mg and 20 mg of D and is further evaluated in the phase II of the study. Toxicity is manageable for patients with serum creatinine 〈 2.5 mg/dL but can be significant for AL patients with more severe renal impairment. Lower doses of R, at 10 mg or less every other day or thrice per week should be used in these patients. Accrual in the phase II study is ongoing and updated results will be presented at the meeting. Disclosures: Dimopoulos: Celgene: Honoraria, Research Funding.

Abstract: Abstract 3052 The combination of bortezomib, doxorubicin, and dexamethasone (PAD) has shown efficacy in both relapsed/refractory and untreated, symptomatic multiple myeloma (MM). The activity of this regimen is largely attributed to the recognized synergy between bortezomib and doxorubicin. Bortezomib is capable of reversing resistance to chemotherapy in MM with adverse prognostic features (high-risk myeloma), which has an unfavorable outcome with conventional chemotherapy followed by high-dose therapy and autologous stem cell transplantation (ASCT). In addition, disease status prior to ASCT has prognostic significance for survival, underscoring the need for highly efficient remission induction strategies. In a prospectively designed phase II trial, we focused on the efficacy and safety of the PAD combination as front-line treatment for high-risk myeloma. The study recruited patients aged ≤70 years with newly diagnosed, symptomatic MM with high-risk features (defined by at least one of the following criteria: ISS stage II/III according to serum albumin and beta2-microglobulin, and/or detection of 13q deletion by FISH or conventional karyotyping). Between 2005 and 2008, 40 patients were enrolled in the protocol. The median age of patients was 59 years (range: 41–70 years), and 27 (67.5%) were male. Each 21-day cycle of PAD included bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11 plus doxorubicin 9 mg/m2 on days 1–4, and dexamethasone 40 mg on days 1–4 and 8–11. According to protocol, patients received 4 induction cycles of PAD before proceeding to stem cell harvest and ASCT. Acyclovir and ciprofloxacin prophylaxis were routinely used. Patients were evaluated for toxicity at each cycle and for response after the end of the fourth cycle. The primary study endpoint was the response rate at the end of induction (assessed by the International Myeloma Working Group uniform response criteria, 2006). Secondary endpoints were toxicity, progression-free survival (PFS), overall survival (OS), ability to mobilize stem cells, and response after ASCT. ISS stage was I in 2 patients (5%), II in 18 (45%), and III in 20 (50%). Nine out of 40 patients (22.5%) presented with renal failure (creatinine 〉 2mg/dl) due to myeloma at diagnosis. Deletion 13q was detected in 19 patients. Bone disease was present in 30 patients (75%) at diagnosis, and 19 (47.5%) had ≥3 lytic lesions on plain skeleton radiograms. Median patient follow-up time was 28.3 months (range, 1.4–49.3). All patients completed the 4 cycles of PAD, with the exception of one who died during the 2nd cycle. The overall response rate assessed after the 4th cycle of PAD was 95%. Complete remission (CR) was achieved in 12/39 (31%), very good partial remission (VGPR) in 15/39 (38.5%), and PR in 10/39 (25.5%). Thirty-one patients were considered eligible for ASCT, and an adequate stem cell harvest was achieved in all. Following ASCT, CR rate reached 52% (16/31) with a CR+VGPR rate of 84% (26/31). PFS was 67% at 2.1 years, and calculated OS was 81.4% at 4 years (Figures 1 and 2). Factors associated with shorter OS were beta2-microglobulin ≥5.5 mg/L (p=0.03), and ISS stage III (p=0.03). By assessment of the glomerular filtration rate (GFR), a significant improvement in renal function was demonstrated after induction with PAD (median GFR pre- and post-induction: 59.7 versus 82.1 ml/min, respectively; p 〈 0.001). Improvement in kidney function was observed irrespective of the type of response. There was only one treatment-related death secondary to infection. Toxicities were manageable in general, and included grade 3–4 neutropenia in 8/40 patients (20%), grade 3–4 thrombocytopenia in 4/40 (10%), and grade 3 peripheral neuropathy in 4/40 (10%). No grade 4 peripheral neuropathy was encountered. We conclude that the PAD regimen is very effective, and produces high-quality responses in a substantial proportion of patients with newly diagnosed, high-risk MM (CR+VGPR: 69.5%). PAD is well tolerated and does not compromise stem cell mobilization and harvest. Upfront treatment with 4 cycles of PAD followed by ASCT resulted in notable PFS and OS rates in this patient group with adverse-prognosis MM. PAD was shown to be particularly beneficial in patients with renal impairment at diagnosis due to myeloma. Disclosures: Baltathakis: Janssen-Cilag: Research Funding. Terpos:Janssen-Cilag: Honoraria. Delimpasi:Janssen-Cilag: Research Funding. Dimopoulos:Janssen-Cilag: Honoraria. Harhalakis:Janssen-Cilag: Research Funding.

Abstract: Introduction: Daratumumab (DARA) is a human IgGκ monoclonal antibody targeting CD38 with a direct on-tumor and immunomodulatory mechanism of action. DARA is approved as monotherapy or in combination with standard-of-care regimens for the treatment of relapsed or refractory multiple myeloma (RRMM). In the primary analysis (median follow-up, 16.9 months) of the phase 3 APOLLO study (NCT03180736), the addition of DARA to pomalidomide and dexamethasone (D-Pd) showed a significant progression-free survival (PFS) improvement over pomalidomide and dexamethasone (Pd) alone in patients (pts) with RRMM (Dimopoulos MA, et al. Lancet Oncol. 2021;22[6]:801-812). Here, we report results from the APOLLO study, including outcomes of pts refractory to lenalidomide based on the last dose of lenalidomide received. Methods: Eligible pts were ≥18 years of age, had RRMM, had received ≥1 prior line of therapy (including both a proteosome inhibitor and lenalidomide), and had responded to prior treatment; pts with only 1 prior line of therapy were required to be refractory to lenalidomide. Pts were randomized 1:1 to Pd ± DARA, stratified via International Staging System disease stage (I vs II vs III) and number of lines of prior therapy (1 vs 2-3 vs ≥4). All pts received 28-day cycles of pomalidomide (4 mg PO daily on Days 1-21) and dexamethasone (40 mg [20 mg for pts ≥75 years of age] , PO daily on Days 1, 8, 15, and 22). Pts in the D-Pd group received DARA subcutaneously (DARA SC; 1,800 mg; co-formulated with recombinant human hyaluronidase PH20 [rHuPH20; ENHANZE ® drug delivery technology, Halozyme, Inc.]) or, prior to a protocol amendment, intravenously (DARA IV; 16 mg/kg; n=7) weekly in Cycles 1-2, every 2 weeks in Cycles 3-6, and every 4 weeks thereafter. Pts receiving DARA IV were allowed to switch to DARA SC starting on Day 1 of Cycle 3 or later. All pts were treated until disease progression or unacceptable toxicity. The primary endpoint was PFS. Results: In total, 304 pts were randomized (D-Pd, n=151; Pd, n=153). At the time of randomization, 120 (79.5%) pts in the D-Pd group and 122 (79.7%) pts in the Pd group were refractory to lenalidomide. Among pts refractory to lenalidomide, the last dose of lenalidomide received was 5-10 mg in 30 (25.0%) pts in the D-Pd group and 31 (25.4%) pts in the Pd group and was 15-25 mg in 86 (71.7%) pts in the D-Pd group and 89 (73.0%) pts in the Pd group. With a median follow-up of 16.9 months, the median PFS in the overall population was 12.4 months in the D-Pd group versus 6.9 months in the Pd group (hazard ratio [HR], 0.63; 95% confidence interval [CI] , 0.47-0.85; P=0.0018); the estimated 18-month PFS rate was 42.1% for the D-Pd group and 25.5% for the Pd group. Among pts refractory to lenalidomide, the median PFS was 9.9 months in the D-Pd group and 6.5 months in the Pd group (HR, 0.66; 95% CI, 0.49-0.90). For lenalidomide-refractory pts who last received a dose of 5-10 mg lenalidomide, the median PFS was 10.3 months for the D-Pd group and 8.5 months for the Pd group (HR, 0.75; 95% CI, 0.41-1.36); for lenalidomide-refractory pts who last received a dose of 15-25 mg lenalidomide, the median PFS was 10.7 months for the D-Pd group and 6.1 months for the Pd group (HR, 0.61; 95% CI, 0.42-0.88) (Figure). Grade 3/4 treatment-emergent adverse events occurred in 130 (87.3%) pts in the D-Pd group and 123 (82.0%) pts in the Pd group; the most frequently reported (≥15% in both groups) were neutropenia (67.8% vs 50.7%), thrombocytopenia (17.5% vs 18.0%), and anemia (16.8% vs 21.3%). Grade 3/4 pneumonia occurred in 20 (13.4%) pts in the D-Pd group and 10 (6.7%) of pts in the Pd group. Serious adverse events occurred in 75 (50.3%) pts in the D-Pd group and 59 (39.3%) pts in the Pd group. Conclusion: The addition of DARA to Pd provided a PFS benefit in the overall pt population and among pts refractory to lenalidomide. The safety profile observed in the APOLLO trial was consistent with previous reports for DARA SC and Pd. Additional analyses for lenalidomide-refractory pts, as well as efficacy and safety data for the overall population at longer follow up, will be presented. Figure 1 Figure 1. Disclosures Sonneveld: Celgene/BMS: Consultancy, Honoraria, Research Funding; SkylineDx: Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Karyopharm: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding. Terpos: Celgene: Consultancy, Honoraria, Research Funding; Genesis: Consultancy, Honoraria, Research Funding; GSK: Honoraria, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Research Funding; Novartis: Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; BMS: Honoraria; Amgen: Consultancy, Honoraria, Research Funding. Boccadoro: Sanofi, Celgene, Amgen, Janssen, Novartis, Bristol-Myers Squibb, and AbbVie: Honoraria; Janssen and GSK: Membership on an entity's Board of Directors or advisory committees; Sanofi, Celgene, Amgen, Janssen, Novartis, Bristol-Myers Squibb, and Mundipharma: Research Funding. Delimpasi: Takeda: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Amgen: Honoraria, Speakers Bureau. Beksac: Amgen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: 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, Speakers Bureau; Oncopeptides: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Katodritou: GSK, Amgen, Karyopharm, Abbvie, Janssen-Cilag, Genesis Pharma, Sanofi: Honoraria, Research Funding. Moreau: Celgene BMS: Honoraria; Sanofi: Honoraria; Oncopeptides: Honoraria; Janssen: Honoraria; Amgen: Honoraria; Abbvie: Honoraria. Symeonidis: Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; MSD: Consultancy, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi/Genzyme: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Demo: Research Funding; WinMedica: Research Funding; GenesisPharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astellas: Consultancy, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Bila: Janssen, Takeda, AMGEN: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Oriol: Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS/Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees. Mateos: Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria; Oncopeptides: Honoraria; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bluebird bio: Honoraria; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sea-Gen: 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; Celgene - Bristol Myers Squibb: 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; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees. Einsele: Janssen, Celgene/BMS, Amgen, GSK, Sanofi: Consultancy, Honoraria, Research Funding. Orfanidis: Health Data Specialists: Current holder of individual stocks in a privately-held company. Kampfenkel: Janssen: Current Employment. Qiu: Janssen: Current Employment. Amin: Janssen: Current Employment, Current equity holder in publicly-traded company. Kosh: Janssen: Current Employment. Tran: Janssen: Current Employment, Current equity holder in publicly-traded company. Carson: Janssen: Current Employment. Dimopoulos: Beigene: Honoraria; Takeda: Honoraria; Janssen: Honoraria; Amgen: Honoraria; BMS: Honoraria. OffLabel Disclosure: The regimen is approved for patients who have received at least two prior therapies, whereas the APOLLO study included patients who have received at least 1 prior therapy.

Abstract: Multiple myeloma of the central nervous system (CNSMM) is a rare and severe clinical entity. The efficacy of novel agents in this setting has not been sufficiently explored. Our aim was to describe the incidence, characteristics and outcome of CNSMM in the era of novel agents, to search for prognostic factors of post CNSMM survival and explore the efficacy of novel agent-based combinations (NAC). Data were provided by 8 Centers of the Greek Myeloma Study Group from January 2000 to December 2013. Documentation of CNSMM required: biopsy that proved CNSMM or MRI/CT findings consistent with CNSMM or detection of plasma cells (PCs) and/or monoclonal immunoglobulin (MC) in the cerebrospinal fluid (CSF). Response to CNSMM treatment was defined as improvement/normalization of at least one of the aforementioned variables. Twenty-four (M/F: 10/14; median age: 63.5 years, range 24-97 years) of 3107 newly diagnosed symptomatic MM patients, who were diagnosed in the same centers during the same period of time, developed CNSMM (0.8%); 2 of them were newly diagnosed and 22 had received previous therapies (6/22 had CNS involvement as the sole feature of MM). Fourteen patients had IgG MM, 2 IgA, 3 light chain, 1 IgD and 4 non-secretory MM. The median time to CNSMM diagnosis was 28.5 months (range: 0-98 months). Clinical manifestations included: visual disturbances/diplopia (37%), paresis/paraplegia (29%), lethargy/confusion (25%), headache (16%) and cranial nerve palsy (12%). MRI or CT documentation was available in 20/24 patients and revealed parenchymal lesions (35%), leptomeningeal lesions (10%), direct MM extension (20%), parenchymal/leptomeningeal (10%), parenchymal/direct MM extension (15%) or leptomeningeal/direct MM extension (10%). Diagnostic lumbar puncture was performed in 17 patients and in 10/17 PCs were detected in the CSF (median number of PCs/μL was 172.5/μL, range: 5-2550/μL). LDH and albumin in the CSF was high in all patients, while MC was detected in the CSF of 4 patients. Sixteen patients (67%) had additional extramedullary disease (EMD) or plasma cell leukemia (PCL) prior to CNSMM diagnosis (plasmacytomas: 9 patients, PCL primary/secondary: 3/3 patients, EMD/PCL: 1 patient). Molecular cytogenetics were available in 12/24; 4 patients had high risk cytogenetics. Patients who developed CNSMM after frontline therapy (n=22) had higher LDH at the time of CNS involvement compared to initial MM diagnosis (267 U/L vs 191 U/L; p=0.02). NAC had been given in 17/22 (77%) such patients prior to CNSMM diagnosis (bortezomib-based: 17, IMiD-based: 13, both: 13). The median number of previous MM treatment lines in these patients was 3 (range: 1-5). Treatment of CNSMM included NAC (bortezomib-based 9 and IMiD-based 3 patients), chemotherapy alone (7 patients) and only intrathecal infusions (ITI) with MTX or AraC (3 patients); 7 patients received both systematic therapy and ITI. Additional radiotherapy (RT) was given to 8 patients; one patient underwent ASCT consolidation. Regarding CNSMM response, 10/22 treated patients had improvement or normalization of initial CNS findings and 6 of them relapsed. At the time of evaluation, 2 patients were alive and 22 patients had died (MM progression: 13, sepsis: 6, cerebral hemorrhage: 2, leishmaniasis: 1 and CNSMM progression: 1). The median post CNSMM survival was 3 months (95% CI: 1.9-4.1). The median post CNSMM survival for patients treated with NAC vs. others was 4 (95% CI: 0-8.6) vs. 2 months (95% CI: 0.7-3.3), respectively (p 〉 0.05). Additional RT did not improve survival (p 〉 0.05). In the cox regression analysis, prior treatment with NAC and presence of EMD/PCL prior to CNSMM diagnosis marginally predicted for shorter post CNSMM survival (p=0.05 and 0.068, HzR: 3.03 and 2.57, respectively). The median post CNSMM survival for previously NAC-exposed patients was 2 months (95% CI: 1-2.9) vs. 6 months (95% CI: 0.8-11) for NAC-naive patients (p=0.03), while that of patients with prior EMD/PCL was 2 months (95% CI: 1.3-2.6) vs. 8 months (95% CI: 0-18) of the others (p=0.06). In the era of novel agents the incidence of CNSMM remains low, but yet outcome is extremely poor. In our study, treatment with NAC ± RT and ITI did not offer any survival advantage. Treatment with NAC and presence of EMD/PCL prior to CNSMM diagnosis seems to predict for shorter post CNSMM survival. Patients with EMD/PCL should be monitored more firmly in order to detect early manifestations of CNSMM. Disclosures No relevant conflicts of interest to declare.

Abstract: Abstract 948 Renal impairment (RI) is a common presenting complication of multiple myeloma (MM) and is associated with increased risk of treatment related toxicity and early death. The management of RI in patients with MM requires vigorous supportive measures and the immediate institution of antimyeloma therapy. After the introduction of novel agents a significant improvement of the survival of patients with MM has been observed; however, the impact of these therapies on the survival of MM patients who present with RI has not been extensively studied. In order to analyze the impact of RI in newly diagnosed patients with MM over the past 20 years, we analyzed 1773 patients with symptomatic myeloma who were treated within the Greek Myeloma Study Group (GMSG). Patients were divided in groups according to the date of initial treatment (1/1/1990-31/12/1994, 1/1/1995-31/12/1999, 1/1/2000-31/12/2004, after 1/1/2005). Thalidomide became available in Greece after 1/1/2000 and bortezomib after 1/1/2005. eGFR was calculated by the modified MDRD formula and the degree of RI was rated as severe when eGFR was 〈 30 ml/min, moderate when eGFR was 30–59 ml/min and mild (or no RI) when eGFR 〉 60 ml/min. The frequency of RI over time was similar as well as the proportion of patients who presented with severe RI (17% vs. 21% vs. 17% vs. 19%) for the respective time periods (p=0.496). More patients 〉 65 years started therapy after 2000 (44% vs. 50% vs. 59% vs. 59%, respectively, p 〈 0.001), especially patients 〉 75 years (13% vs. 18% vs. 24% vs. 32%, respectively, p 〈 0.001). Anemia (Hb 〈 10 g/dl; p=0.007) and ISS-3 disease (p=0.001) were more common after 1/1/1995; there were no other significant differences in the characteristics of the patients during the respective time periods. No patients received upfront novel agents before 31/12/1999, while 20% received upfront novel agent in the period 2000–2004 (almost exclusively thalidomide) and 73% after 1/1/2005 (mostly thalidomide and bortezomib). Myeloma response (≥PR) to frontline therapy was achieved in 56.5% & 54% of patients in the period 1990–1994 & 1995–1999 vs. 67% and 72% of patients in the periods 2000–2004 and after 2005 (p 〈 0.001). The median survival of patients has improved significantly during the past 20 years: 39 months (1990-1994), 31 months (1995-1999), 40.5 months (2000-2004), 54 months after 2005 (p 〈 0.001). The median OS for patients with severe RI has improved significantly from 18 months & 19.5 months in the 1990–1994 & 1995–1999 to 29 months and 32 months for the periods 2000–2004 and after 2005 (p=0.005). For patients with moderate RI the OS improved from 33 & 26 months between 1990–1994 & 1995–1999 to 40 & 44 months in the periods 2000–2004 and after 2005 (p=0.003). For patients with an eGFR ≥60 ml/min the OS improvement was less pronounced (48.5 months vs. 45 months vs. 51 months for the periods 1990–1994 & 1995–1999 & 2000–2004 respectively (p=0.076) and only after 2005 a significant improvement in OS is observed (median OS has not been reached; 3-year OS rate is 73%, p 〈 0.001). For patients with severe RI early death rates ( 〈 2 months from initiation of therapy) were 12% vs. 7% for patients with moderate RI vs. 3% for patients with mild or no RI (p 〈 0.001) and remained unchanged over time. We then adjusted for differences between groups in a multivariate model: treatment after 1/1/2000 was independently associated with improved survival compared to patients treated before 31/12/1999 (p 〈 0.001). After adjusting for the degree of RI in the model, the hazards ratios (HR) for death for patients with severe RI for the 2000–2004 and after 2005 periods were 0.485 & 0.387 respectively compared to patients treated before 2000 (p 〈 0.001 for both comparisons). For patients with moderate RI the respective HRs were 0.65 (p=0.003) & 0.57 (p=0.001), while for patients with mild or no RI the HRs were 0.85 (p=0.1) & 0.66 (p=0.003) for the 2000–2004 and after 2005 periods, respectively. In conclusion, the incidence of RI at diagnosis of MM has remained unchanged during the past 20 years, despite the increasing numbers of older patients who are diagnosed and treated for MM. The risk of early death is almost 2 to 4-fold higher in patients with severe RI vs. patients with moderate or no RI and has not improved over time. However, after the introduction of novel therapies there has been a significant improvement of the survival of patients with RI, which is more pronounced in patients with severe RI. Disclosures: No relevant conflicts of interest to declare.

Abstract: Abstract 1819 Poster Board I-845 Several older studies have shown that high serum LDH is associated with features of advanced disease and with an inferior survival of symptomatic patients with MM who require treatment. It is however unclear whether LDH may add to the prognostic value of ISS and whether it may retain its prognostic significance in patients who have been exposed to novel agent-based therapies either at diagnosis or later in the course of their disease. In order to address these issues we analyzed 996 consecutive symptomatic patients who were included in the data base of the Greek Myeloma Study Group and who received frontline treatment between January 1995 and December 2008. Elevated serum LDH to ≥300 IU/L (normal levels 〈 225 IU/L) was observed in 11% of patients. High LDH was seen more often in patients with impaired performance status (p 〈 0.01), with anemia (p 〈 0.01), with thrombocytopenia (p 〈 0.01), with renal impairment (p 〈 0.01), with high ISS (p 〈 0.01), and with hypercalcemia (p=0.01). The median survival of all patients was 40 months with a clear improvement for patients who started treatment after January 2000 as compared to patients who started treatment before that date (50 months versus 31 months; p 〈 0.01). Multiple clilnical and laboratory variables correlated with the probability of survival in univariate analysis. A multivariate analysis showed that the following variables had an independent prognostic significance: LDH (p 〈 0.001), ISS (p 〈 0.001), performance status (p 〈 0.001), age (p 〈 0.001) and platelet count (p 〈 0.001). The median survival of patients with high versus normal LDH was 15 months versus 44 months (p 〈 0.001). High LDH was observed in 7% of patients with ISS-1, in 10% of ISS-2 and 12% of ISS-3. Within each ISS subgroup the presence of high LDH was associated with a worse median survival. In ISS-1 the median survival of patients with high LDH was 22 months (CI 95%: 10-35) while the median survival of those with normal LDH was 76 months (CI 95%: 61-91; p 〈 0.01). Similarly in ISS-2 the median survival of patients with high and normal LDH was 11 months (CI 95%: 7-14) and 40 months (CI 95%: 32-48), respectively (p 〈 0.001), while in ISS-3 it was 17 months (CI 95%: 11-23) and 27 months (CI 95%: 21-33), respectively (p 〈 0.01). Subsequently, patients were separated into two groups: patients who started treatment between January 1995 and December 1999 and patients who started therapy after January 2000 i.e. patients who had access to novel agent-based therapy. In both groups the presence of high LDH was related with statistically worse survival. In patients who received treatment before January 2000, the median survival in the high LDH group was 10 months (CI 95%: 4-16) versus 36 months in the normal LDH group (CI 95%: 31-42; p 〈 0.001). Similarly, in patients who received treatment after January 2000, the median survival in the high LDH group was 21 months (CI 95%: 12-29) versus 51 months in the normal LDH group (CI 95%: 40-63; p 〈 0.001). We conclude that serum LDH is a readily available and inexpensive variable which has a major impact on the survival of patients with myeloma even when they belong to a low or intermediate ISS subgroup and even when they receive novel agent-based therapy. Disclosures No relevant conflicts of interest to declare.

Abstract: Introduction: Patients with multiple myeloma (MM) have a high rate of relapse resulting in a need for multiple lines of therapy. In contrast to MM with standard risk cytogenetics (SR-Cyto), high-risk cytogenetics (HR-Cyto) in MM such as del(17p), t(4;14), t(14;16), and gain(1q) (≥3 copies), can result in shorter progression-free survival (PFS) and overall survival (OS) with less durable responses. Treatment regimens that can overcome the negative effect of HR-Cyto abnormalities are required to address this area of unmet medical need. Exportin 1 (XPO1), is overexpressed in many hematologic and solid tumor malignancies including MM, and exports tumor suppressor proteins from the nucleus to the cytoplasm, leading to their inactivation. Elevated levels of XPO1 are correlated with more aggressive MM and resistance to therapy and confers a poor prognosis. The potent oral XPO1 inhibitor, selinexor, has been approved as a triplet combination with bortezomib and dexamethasone for previously-treated MM. In the Phase 3 BOSTON study, treatment with XVd in patients with previously treated MM significantly prolonged median PFS and improved the overall response rate (ORR), with a trend towards a prolonged OS amongst all patients as well as those with HR cytogenetics. Methods: We performed post hoc analyses on patients with previously-treated MM from the XVd arm of the Phase 1b/2 study STOMP (NCT02343042) and the Phase 3 BOSTON (NCT03110562) study to determine the effects of cytogenetic abnormalities on outcomes. The HR-Cyto group included patients with at least one of the following cytogenetic abnormalities at initial diagnosis or screening: del(17p), t(4;14), t(14;16), or gain(1q) (≥3 copies). Efficacy was based on independent review committee. Results: A total of 106 patients with HR-Cyto were identified, including del(17p) (n=25), t(4;14) (n=25), t(14;16) (n=10), and gain(1q) (n=80). There were 131 patients classified as SR-Cyto including those with unknown cytogenetics. Baseline demographics were similar between groups with median age of 66 years old (range 40-87). Patients with HR-Cyto had a median PFS of 12.9 months and patients with SR-Cyto had a median PFS of 16.6 months; PFS on the BOSTON Vd control arm were 8.6 and 9.5 months with HR- and SR-Cyto, respectively. Of the individual abnormalities, a PFS of 13.2 and 13.9 months was observed in the t(4;14) and gain1q subgroups, respectively. Of the HR-Cyto subgroups with more than 10 patients, a similar median OS was observed in comparison to SR-Cyto and ranged from 20.4 months to not reached. The response of XVd treatment was maintained across HR-Cyto risk subgroups, with an ORR of 76.4% overall and the following values for subgroups: del(17p) (72.0%), t(4;14) (88.0%), and gain1q (73.8%). The ORR of the SR group was 69.5%. Of all patients that received XVd, there were 6 CRs (5.7%) and 32 VGPRs (30.2%) in the HR group and 9 CRs (6.9%) and 29 VGPRs (22.1%) in the SR group. The ORRs on the BOSTON Vd control arm were 57.7% and 64.7% for HR- and SR-Cyto, respectively. The rates of the most common treatment emergent adverse events (TEAEs) of any grade were similar across risk groups (HR- vs SR-Cyto): thrombocytopenia (65.1% vs. 54.2%), nausea (53.8% vs. 53.4%), fatigue (47.2% vs. 45.0%) decreased appetite (37.7% vs. 42.0%) and anemia (34.6% vs 40.5%). Rates of AEs of any grade peripheral neuropathy (PN) were 35.8% overall, 40.0% in del(17p), t(4;14) (40.0%), t(14;16) (30.0%), gain(1q) (38.8%), and 23.7% in the SR group. The rates of PN in the HR and SR groups of the XVd arm of the BOSTON and STOMP studies were 37.1% and 29.6% and 11.1% and 15.2%, respectively. The corresponding rates for Vd alone in the BOSTON study were 48.6% and 47.0%. Conclusions: Patients with MM with HR-Cyto treated with XVd demonstrated a comparable ORR and PFS, with a manageable safety profile compared to patients with SR-Cyto, supporting the use of XVd in patients with any cytogenetic profile. These results are consistent with the distinct and broad mechanism of action associated with XPO1 inhibition and the use of the agent in earlier lines of therapy. Further assessment of selinexor in combination with other therapies in patients with MM across the entire cytogenetic spectrum is warranted. Figure 1 Figure 1. Disclosures Bahlis: Sanofi: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; GlaxoSmithKline: Consultancy, Honoraria; Genentech: Consultancy; BMS/Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria. Richard: Karyopharm, Janssen: Honoraria. White: Amgen, Antengene, BMS/Celgene, Forus, GSK, Janssen, Karyopharm, Sanofi, Takeda: Consultancy, Honoraria. Chen: Gilead: Research Funding; BMS, Janssen, Abbvie, Novartis, Gilead, AstraZeneca: Consultancy. Delimpasi: Amgen: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Takeda: Honoraria, Speakers Bureau. Sutherland: Amgen: Consultancy; Janssen: Consultancy, Research Funding; GSK: Research Funding; Celgene: Consultancy; Karyopharm: Research Funding. Sebag: Janssen: Research Funding; Bristol Myers-Squibb: Consultancy, Honoraria; Karyopharm Therapeutics: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria. Gavriatopoulou: GSK: Honoraria; Janssen: Honoraria; Takeda: Honoraria; Genesis: Honoraria; Sanofi: Honoraria; Karyopharm: Honoraria; Amgen: Honoraria. Lentzsch: Oncopeptides: Consultancy; Sanofi: Consultancy, Research Funding; Karyopharm: Consultancy, Research Funding; Takeda: Consultancy; GSK: Consultancy; AbbVie: Consultancy; Celularity: Consultancy; Janssen: Consultancy; Caelum Biosciences: Consultancy, Current holder of individual stocks in a privately-held company; Ossium Health: Consultancy; Magenta Therapeutics: Current equity holder in publicly-traded company; Kadmon: Current equity holder in publicly-traded company. Chari: Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi Genzyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Research Funding; Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees; Secura Bio: Consultancy, Membership on an entity's Board of Directors or advisory committees; Shattuck Labs: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Research Funding; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees; Millenium/Takeda: Consultancy, Research Funding; Pharmacyclics: Research Funding; Janssen Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS/Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Antengene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding. Kriachok: Takeda, Roche, Abbvie, Janssen, MSD, Pfizer: Honoraria, Speakers Bureau; Takeda, Roche, Abbivie, Janssen, MSD: Consultancy. Dimopoulos: BMS: Honoraria; Janssen: Honoraria; Amgen: Honoraria; Takeda: Honoraria; Beigene: Honoraria. Auner: Janssen: Speakers Bureau; Amgen: Research Funding; Takeda, Karyopharm: Other: Advisory role. Leleu: Bristol-Myers Squibb: Honoraria; Carsgen Therapeutics Ltd: Honoraria; Celgene: Honoraria; Gilead Sciences: Honoraria; Janssen-Cilag: Honoraria; Karyopharm Therapeutics: Honoraria; Merck: Honoraria; Mundipharma: Honoraria; Novartis: Honoraria; Oncopeptides: Honoraria; Pierre Fabre: Honoraria; Roche: Honoraria; Sanofi: Honoraria; Amgen: Honoraria; AbbVie: Honoraria; Takeda: Honoraria, Other: Non-financial support. Usenko: Janssen: Consultancy, Honoraria, Other: Clinical Trials Investigator; AbbVie: Consultancy, Honoraria, Other: Clinical Trials Investigator; Pfizer: Consultancy, Honoraria; Acerta: Other: Clinical Trials Investigator; Ascentage: Other: Clinical Trials Investigator; Celgene: Other: Clinical Trials Investigator; Il-Yang: Other: Clinical Trials Investigator; Karyopharm: Other: Clinical Trials Investigator; Oncopeptides: Other: Clinical Trials Investigator; Rigel: Other: Clinical Trials Investigator; Takeda: Other: Clinical Trials Investigator; UCB: Other: Clinical Trials Investigator. Hajek: Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, 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; Pharma MAR: Consultancy, Honoraria; Novartis: Consultancy, Research Funding; AbbVie: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding. Venner: Janssen: Honoraria; Amgen: Honoraria; Takeda: Honoraria; Celgene: Research Funding; Amgen: Research Funding. Garg: Takeda Janssen Novartis Sanofi: Other: Travel Accommodations, Expenses; Amgen Janssen Novartis Sanofi Takeda: Honoraria; University Hospital Leicester: Current Employment. Quach: Antengene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen/Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; CSL: Consultancy, Membership on an entity's Board of Directors or advisory committees. Jagannath: Karyopharm Therapeutics: Consultancy; Bristol Myers Squibb: Consultancy; Legend Biotech: Consultancy; Janssen Pharmaceuticals: Consultancy; Sanofi: Consultancy; Takeda: Consultancy. Moreau: Celgene BMS: Honoraria; Sanofi: Honoraria; Janssen: Honoraria; Abbvie: Honoraria; Amgen: Honoraria; Oncopeptides: Honoraria. Levy: Takeda, Celgene, Seattle Genetics, AbbVie, Jazz Pharmaceuticals, Gilead Sciences, Bristol-Myers Squibb, Amgen, Spectrum Pharmaceuticals,Janssen.: Consultancy. Badros: J & J: Research Funding; Janssen: Research Funding; BMS: Research Funding; GlaxoSmithKline: Research Funding. Anderson: Celgene, BMS, Janssen, GSK, Karyopharm, Oncopeptides, Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Mateos: Oncopeptides: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sea-Gen: 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; Celgene - Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: 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; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; Bluebird bio: Honoraria; AbbVie: Honoraria; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees. Cavo: AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; GlaxoSmithKline: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Adaptive Biotechnologies: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Accommodations, Speakers Bureau; Novartis: Honoraria; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES, Speakers Bureau; Bristol-Myers Squib: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. DeCastro: Karyopharm: Current Employment, Current equity holder in publicly-traded company. Chai: Karyopharm: Current Employment. Van Domelen: Karyopharm: Current Employment, Current equity holder in publicly-traded company. Mishal: Karyopharm: Current Employment. Bentur: Karyopharm Therapeutics: Current Employment, Current equity holder in publicly-traded company. Shah: Karyopharm: Current Employment. Shacham: Karyopharm: Current Employment, Current equity holder in publicly-traded company, Patents & Royalties: (8999996, 9079865, 9714226, PCT/US12/048319, and I574957) on hydrazide containing nuclear transport modulators and uses, and pending patents PCT/US12/048319, 499/2012, PI20102724, and 2012000928) . Kauffman: Karyopharm Therapeutics Inc.: Current Employment, Current equity holder in publicly-traded company. Richardson: Secura Bio: Consultancy; Sanofi: Consultancy; AstraZeneca: Consultancy; Oncopeptides: Consultancy, Research Funding; Janssen: Consultancy; Protocol Intelligence: Consultancy; Takeda: Consultancy, Research Funding; Regeneron: Consultancy; Celgene/BMS: Consultancy, Research Funding; GlaxoSmithKline: Consultancy; AbbVie: Consultancy; Karyopharm: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding.