Tandon, Nidhi

AbstractBackgroundMagnetic resonance imaging (MRI) in patients with legacy cardiovascular implantable electronic devices (CIEDs) in situ is likely underutilized. We hypothesized the clinical benefit of MRI would outweigh the risks in legacy CIED patients.MethodsThis is a single‐center retrospective study that evaluated and classified the utility of MRI using a prospectively maintained database. The outcomes were classified as aiding in diagnosis, treatment, or both for the patients attributable to the MRI. We then assessed the incidence of adverse effects (AE) when the MRI was performed.ResultsIn 668, MRIs performed on 479 patients, only 13 (1.9%) MRIs did not aid in the diagnosis or treatment of the patient. Power‐on reset events without clinical sequelae in three scans (0.45%) were the only AE. The probability of an adverse event happening without any benefit from the MRI scan was 1.1 × 10−4. A maximum benefit in diagnosis using MRI was obtained in ruling out space‐occupying lesions (121/185 scans, 65.4%). Scans performed in patients for elucidating answers to queries in treatment were most frequently done for disease staging at long term follow‐up (167/470 scans, 35.5%). Conservative treatment (184/470 scans, 39%) followed by medication changes (153/470 scans, 28.7%) were the most common treatment decisions made.ConclusionsThe utility of MRI in patients with non‐MRI‐conditional CIEDs far outweighs the risk of adverse events when imaging is done in the context of a multidisciplinary program that oversees patient safety.

Abstract Introduction: IgM light chain amyloidosis (AL) is a rare complication of IgM associated disorders, with very limited data on biology and outcomes. Our study compares the clinical characteristics, laboratory findings and outcomes in a large cohort of patients with IgM vs. non-IgM AL to delineate the underlying disease biology of this entity. Methods: Patients with newly diagnosed AL (2006-15) were identified from a prospectively maintained institutional database and grouped by IgM heavy chain. Bone marrow (BM) morphology was reviewed by an expert hematopathologist (RLK). FISH testing included probes for t(11;14) and trisomies of odd numbered chromosomes. MYD88L265P testing was carried out by allele specific PCR and CXCR4WHIM mutation testing was performed by bridged nucleic acid (BNA)-enhanced Sanger sequencing. Results: Patients with IgM AL comprised 6.6% (75/1128) of the study cohort. Baseline characteristics are listed in Table 1. IgM AL patients were older and had a higher proportion of males. They had less frequent cardiac involvement (60 vs. 75%) and less frequent involvement of > 1 organ. Light chain burden was lower in this group (dFLC 12.5 vs. 22.7 mg/dL), while there was no difference in BM clonal cell percentage (10% each). Morphology: BM morphology in 71 patients with IgM AL revealed a pure plasma cell disorder (PPCD type) in 25% (n=18); low-grade B-cell lymphoma (LGBCL) with plasmacytic features (LPL type) in 62% (n=44) [well defined LPL: 38% (n=27), LGBCL with plasmacytic features: 24% (n=17)]; LGBCL, other: 6% (n=4). In the remaining 7%, three patients had other diagnoses and no BM disease in two patients. Median clonal cell % in LPL vs. PPCD type IgM AL was 20% vs. 5%, p<0.001. Genetics: In patients with IgM AL vs. non-IgM AL, t(11;14) was present in 27% vs. 49%, p=0.009 and trisomies in 9% vs. 24% of patients, p=0.06, respectively. In the IgM AL cohort, MYD88 mutation was seen in 56% (23/41) & CXCR4 mutation in 15% (5/34; S388 type: 3, other: 2) of patients. Importantly, MYD88 and CXCR4 mutations were found only in patients with LPL morphology, while t(11;14) was found only in the PPCD morphology group. There were no patients with both t(11;14) and MYD88 abnormalities (N=26 for both tested). Mutations seen in the LPL vs. PPCD type IgM AL were: MYD88, 88% (22/25) vs. 0% (0/14), p<0.001 and CXCR4, 26% (5/19) vs. 0% (0/13), p=0.02. Conversely, t(11;14) was seen in 0% (0/18) in LPL type vs. 60% (9/15) in PPCD type IgM AL, p <0.001. Treatment details were known in 63 patients with IgM AL; rituximab-based: 21 (33%), bortezomib/alkylator: 16 (25%), transplant 17 (27%), steroids: one and no treatment: 8 (13%). Treatment in IgM AL LPL type (n=36) was: rituximab based: 16 (44%),bortezomib/alkylator: 5 (14%), transplant: 10 (28%) and none: 5 (14%). In PPCD type [n=17), treatment was rituximab based: 2 (12%), bortezomib/alkylator: 8 (47%), transplant: 7 (41%). At 6 months, very good partial response or better was observed in 26% (10/39) vs. 41% (270/660) of patients with IgM vs. non-IgM AL, p=0.05. There was no difference in overall survival (OS) when all patients with IgM AL were compared to non-IgM AL (Fig 1a). However, when stratified by early (Stage 1/2) or advanced (stage 3/4) 2012 Mayo stage, patients with IgM AL fared worse (Fig 1b-c). On multivariate analysis, IgM AL was an independent predictor for inferior OS [HR with 95% CI: 1.6 (1.1-2.4), p=0.02] after adjusting for age, Mayo 2012 stage and type of therapy (transplant vs. not). However, when OS was adjusted for 6 month VGPR, there was no difference in OS for IgM AL vs. non IgM AL, p=0.2. In the IgM AL cohort, patients with LPL type IgM AL had inferior OS compared with PPCD type IgM AL, 21 vs. 82 months, p=0.01 (Fig 1d). Conclusions: Patients with IgM AL have distinct clinical and genetic features, with lower rates of cardiac involvement and a lower frequency of t(11;14) or trisomies compared with non-IgM AL. Even though IgM AL is a rare entity, we were able to delineate two distinct sub-types of IgM AL: LPL type and PPCD type, with implications for therapy and outcomes. Along with unique morphologic findings, presence of MYD88 and CXCR mutations was only seen in LPL type IgM AL and t(11;14) in PPCD type IgM AL. Despite lower cardiac involvement, IgM AL was associated with inferior OS outcomes, likely due to lower response rates, particularly in LPL IgM AL group, which had the lowest OS. Therapeutic approaches targeted towards disease biology to achieve deep responses are needed in this disorder. Disclosures Sidana: Janssen: Honoraria. Dispenzieri:Celgene, Takeda, Prothena, Jannsen, Pfizer, Alnylam, GSK: Research Funding. Kapoor:Takeda: Research Funding; Celgene: Research Funding. Lacy:Celgene: Research Funding. Kumar:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; KITE: 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; KITE: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Roche: Research Funding; Novartis: Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding. Gertz:Abbvie: Consultancy; Ionis: Honoraria; spectrum: Consultancy, Honoraria; Apellis: Consultancy; Amgen: Consultancy; Prothena: Honoraria; Teva: Consultancy; Alnylam: Honoraria; celgene: Consultancy; Medscape: Consultancy; janssen: Consultancy; Research to Practice: Consultancy; Physicians Education Resource: Consultancy; annexon: Consultancy.

Abstract Introduction High dose chemotherapy and autologous stem cell transplantation (ASCT) is an effective therapy for eligible patients with newly diagnosed systemic AL amyloidosis. Dose attenuated melphalan is used in patients with older age, renal dysfunction, and multi-organ involvement in an effort to limit treatment related mortality. Reducing the dose of melphalan compromises response rates and survival outcomes, but this is often contributed to frailty of these patients. The revised Mayo staging (MS) system improves risk stratification and helps develop risk-adapted therapies. We analyzed the outcomes of ASCT following standard [(200 mg/m2); SD group] versus risk adapted [(140-160 mg/m2); RD group] melphalan conditioning, in the context of the factors typically leading to dose modification. Methods Three hundred and twenty nine patients with newly diagnosed systemic AL amyloidosis who underwent conditioning with melphalan followed by ASCT at Mayo Clinic between 2006 and 2015 were identified using existing databases. The clinical and laboratory data, treatment and follow - up details were collected by chart review and analyzed retrospectively. Overall survival(OS) was defined as the time from start of initial therapy until death from any cause or last follow up. Progression free survival(PFS) was defined as the time to relapse or progression requiring change or reinstitution of treatment or death from any cause. The OS and PFS curves were estimated using Kaplan-Meier method while log rank test was used to estimate their difference. Multivariate survival analysis was performed using the Cox proportional hazards model. Results Among the 329 patients, 240 patients were in SD group and 89 patients were in RD group (1 patient received 120 mg/ m2, 2 received 160 mg/m2 and the rest received 140 mg / m2). In the SD group, median age was 58.5 years (25.6 - 72.3); 59.6% were males; 38.7% / 61.7 %/ 7.5% had cardiac / renal /hepatic involvement; and 47.1% / 35.7% / 8.8% / 8.4% had MS I/II/III/IV. In the RD group, median age was 60.8 years (40 - 73.7); 62.9% were males; 66.3% / 71.9 %/ 11.2% had cardiac / renal /hepatic involvement; and 26.2% / 32.5% / 21.2% / 20% had MS I/II/III/IV. The response rates for patients in the SD group [complete response (CR) - 53.7%, very good partial response (VGPR) - 19.6%, partial response (PR) - 12.5%, no response (NR) - 1.2%, progressive disease (PD) - 1.6%] were significantly higher than patients in the RD group (CR - 34.8%, VGPR - 20.2%, PR - 15.7%, NR - 10.1%, PD - 1.1%) (85.8 vs 70.7%; p < 0.002). The PFS and OS for both the groups according to Mayo stage are presented in Figure 1. Multivariate survival analysis for PFS and OS was performed using age (≤ vs > 70 years), serum creatinine (≤ vs > 2 mg/dL), number of major organs involved (heart, kidney, liver, gastrointestinal tract and autonomic neuropathy), MS (1 vs 2 vs 3 and 4) and dose of melphalan (SD vs RD). The dose of melphalan (p=0.0002), MS (p=0.03) and the number of organs involved (p=0.04) were significant for PFS while the dose of melphalan (p=0.0001) and the MS (p = 0.004) were significant for OS. Conclusion Reducing the dose of melphalan during conditioning for frontline ASCT in systemic AL amyloidosis renders more patients eligible for transplant but compromises on the response rates. There is no impact on PFS and OS in Mayo stage I patients. However the OS as well as PFS in Mayo stage II, III and IV were significantly lower in RD group as compared to SD group. These results suggest a suboptimal outcome with use of reduced dose melphalan, even after accounting for the pother prognostic factors, suggesting that high dose therapy should potentially be limited to those eligible to receive the full dose conditioning. Disclosures Dispenzieri: Jannsen: Research Funding; pfizer: Research Funding; GSK: Membership on an entity's Board of Directors or advisory committees; Alnylam: Research Funding; Prothena: Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding. Kapoor:Takeda: Research Funding; Amgen: Research Funding; Celgene: Research Funding. Kumar:Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Research Funding; BMS: Consultancy; AbbVie: Research Funding; Array BioPharma: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; Glycomimetics: Consultancy; Kesios: Consultancy; Noxxon Pharma: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Millennium: Consultancy, Research Funding.

Abstract Introduction Immunoglobulin light chain amyloidosis (AL Amyloidosis) is a monoclonal plasma cell proliferative disorder that is characterized by tissue deposits of misfolded insoluble κ or λ light chain derived amyloid fibrils, leading to organ dysfunction. The prognosis of patients depends on the number and severity of organ involvement, especially cardiac involvement. Autologous stem cell transplant (ASCT), if eligible, alkylator (melphalan) and novel drugs like proteasome inhibitors (PI) and immunomodulators (IMiD) have improved the overall survival (OS) during the past decades. But still, nearly half of the patients die within a year of diagnosis. We analyzed the factors predicting early relapse / progression or death (within 12 months) after first line therapy for systemic AL amyloidosis. Methods Clinical and laboratory data of all consecutive patients with systemic AL amyloidosis seen at Mayo Clinic within 90 days of their diagnosis, between 2006 and 2015, was collected by chart review and analyzed retrospectively. Patients who died within 3 months of starting the first line treatment were excluded from analysis. Early relapse (ER) was defined as relapse / progression requiring treatment change / re-institution or death within 12 months of starting first line treatment. Patients in the cohort with ER were compared with patients with a follow up of more than 12 months who had a relapse / progression beyond 12 months or had continuing response at the time of analysis. Categorical variables were analyzed using chi - square and Fisher's exact test and continuous variables using Kruskal- Wallis test and Wilcoxon rank sum test. Multivariate analysis was done using logistic regression model. Results Seven hundred and eighty six patients with newly diagnosed systemic AL amyloidosis met the study criteria and were included in the analysis. Among these, 230 (29.3%) patients had ER within 12 months of starting initial therapy while 556 (70.7%) patients either relapsed after 1 year or had continuing response at the time of analysis. Baseline demographics, organ involvement and type of first line therapy are presented in Table1. The median estimated follow up for the entire cohort from start of initial therapy was 62.9 months (95% CI; 59.9, 67.3). The variables included in the univariate and multivariate analyses for factors predicting ER were age at diagnosis (≤ vs > 70 years ), revised mayo stage (I and II vs III and IV), bone marrow plasma cell percentage (BMPC; ≤ 10% vs > 10%), presence of any chromosomal abnormalities, trisomies or IgH translocations by fluorescence in situ hybridization (FISH), multiorgan involvement [(>1 vs 1) (heart, liver, kidney, gastrointestinal tract, autonomic neuropathy), incorporation of ASCT in initial therapy. In univariate analysis, mayo stage (p<0.0001), multiorgan involvement (p=0.0008) and inclusion of ASCT as part of initial therapy (p<0.0001) were significantly associated with ER, while age (p=0.06), BMPC(p=0.9), FISH abnormalities (p=0.2) were not. However, in multivariate analysis, only mayo stage (III + IV vs I + II; p=0.01) and non-inclusion of ASCT in first line treatment (p=0.0001) were significantly predictive of ER. Conclusions Despite the introduction of ASCT and novel drugs, the early mortality in systemic AL amyloidosis remains high. This study demonstrates that patients with ER are older with higher prevalence of cardiac involvement and multiorgan involvement and higher Mayo stage (III and IV). Incorporation of ASCT as part of the initial therapy was associated with reduced early relapse, but it is difficult to separate the influence of the eligibility for ASCT from the effect of ASCT itself. This will help us in characterizing these patients to better understand their mechanisms of resistance to therapy and gives an insight to the type of initial therapy that benefits them. Disclosures Dispenzieri: GSK: Membership on an entity's Board of Directors or advisory committees; Jannsen: Research Funding; Prothena: Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Alnylam: Research Funding; pfizer: Research Funding. Kapoor:Takeda: Research Funding; Amgen: Research Funding; Celgene: Research Funding. Kumar:Celgene: Consultancy, Research Funding; Kesios: Consultancy; BMS: Consultancy; Sanofi: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; Glycomimetics: Consultancy; Millennium: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; AbbVie: Research Funding; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Research Funding.

Abstract Introduction Immunoglobulin light chain amyloidosis (AL Amyloidosis) is a plasma cell disorder characterized by deposition of misfolded insoluble protein fibrils (composed of monoclonal κ or λ light chains) in tissues causing progressive organ dysfunction. Chemotherapy and autologous stem cell transplant (ASCT), when eligible, are standard treatment options but relapses remain inevitable for most patients. However, there is a paucity of literature describing relapsed or refractory patients. We performed a retrospective study to analyze the outcomes upon relapse and the impact of type of therapy and retreatment with the same therapy at relapse. Methods Clinical and laboratory data of 1327 consecutive patients with systemic AL amyloidosis seen at Mayo Clinic within 90 days of their diagnosis, between 2006 and 2015, was collected by chart review and analyzed retrospectively. Of these patients, 219 (16.5%) were lost to follow-up. Among the remaining 1108 patients, 366 patients experienced a documented hematological or organ relapse or progression requiring change of first line or start of second line therapy and form the current study population. Overall survival (OS) was calculated from start of second line treatment or progression mandating therapy until death from any cause or the date of last follow up. The OS was estimated using the Kaplan-Meier method and log rank test was used to estimate the difference in survival curves. Results The median age was 62.8 years (36.1 - 85.3); 63.1% were males; 64.7% / 59.3% / 11.4% had cardiac / renal / hepatic involvement and 24.2% / 32.1% / 23.3% / 20.3% had MS I/II/III/IV. The median estimated follow up for this cohort was 69.4 months (95% CI; 64.4, 76.8) from the start of first line therapy and 45.2 months (95% CI; 36.5, 50.6) from the start of second line therapy or progression requiring treatment. The median time to second line treatment or relapse /progression mandating therapy was 16.2 months (1-93) from the start of first line therapy. At relapse, 14 patients underwent ASCT, 165 were treated with proteasome inhibitor (PI) based therapy, 83 with immunomodulator (IMiD) based therapy, 33 with alkylator based therapy, 15 with a combination of PI and IMiD, 10 with steroids, 8 with other therapies and 38 did not receive treatment. Among the 366 patients, 124 (33.9%) required change or reinstitution of therapy during follow up at the time of analysis. The median time to third line treatment or relapse /progression mandating therapy was 31 months (95% CI; 24, 40.5) from the start of second line treatment. The median overall survival (OS) was 76.4 months (95% CI; 65.2, 83.6) from the start of first line therapy and 38.8 months (95% CI; 29.6, 52.6) from the start of second line therapy. The type of therapy at relapse (ASCT vs PI vs IMiD vs melphalan vs steroids and others) did not alter the time to next therapy (ASCT, 43.1m; PI, 31m; IMiD, 37m; melphalan, 20.8m; steroids and others, 20m; p=0.3) and OS (ASCT, 66.9m; PI, 51.1m; IMiD, 51.3m; melphalan, 37.2m; steroids and others, 80.7m; p=0.9) from the start of the second line treatment; as depicted in Figure 1. Retreatment with a different drug class (as the first line treatment) at relapse significantly reduced the time to next treatment (32.3m vs 22 m; p= 0.01) as compared to same therapy; but did not have any impact on survival (30.8m vs 51.1m; p = 0.5); as presented in Figure 2. Conclusion This study provides novel information about outcomes of patients with systemic AL amyloidosis who relapse or progress after first line therapy which could be useful in planning salvage therapies and designing clinical trials. Retreatment with a different therapy at relapse improves time to next therapy but does not impact OS. Hence, we conclude that the patients can fare well post relapse/ progression and can benefit from various treatment regimens including retreatment with the same agent. Disclosures Dispenzieri: Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Membership on an entity's Board of Directors or advisory committees; Prothena: Membership on an entity's Board of Directors or advisory committees; Jannsen: Research Funding; pfizer: Research Funding; Alnylam: Research Funding; Celgene: Research Funding. Kapoor:Amgen: Research Funding; Takeda: Research Funding; Celgene: Research Funding. Kumar:BMS: Consultancy; Kesios: Consultancy; Glycomimetics: Consultancy; Onyx: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; AbbVie: Research Funding; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Millennium: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding.

Abstract Introduction: Melphalan based chemotherapy is commonly used for treatment of light chain amyloidosis (AL). Patients with AL often receive chemotherapy before autologous stem cell transplantation (ASCT) if they have high plasma cell burden or while awaiting ASCT. Melphalan is an alkylator and can affect bone marrow stem cells. Limited data is available on the effect of melphalan on stem cell mobilization in patients with amyloidosis. This study aims to identify the impact of melphalan therapy on collection of stem cells and ASCT in amyloidosis. Methods: All patients with AL seen at our institution within 90 days of diagnosis over a 10-year period (2006 to 2015) who underwent stem cell harvest were identified from an institutional database. Data pertaining to demographics, diagnosis, treatment, stem cell harvest and ASCT was extracted from the electronic medical records. Analysis was carried out by chi-square and Fisher's exact test for categorical variables and Kruskal-Wallis and Wilcoxon rank sum test for ordinal and continuous variables. Results: Three hundred and seventy two patients with AL who met the inclusion criteria were identified, of whom 10% (n=38) received melphalan based chemotherapy prior to harvesting, 28.5% (n=106) received non-melphalan based chemotherapy and 61.3% (n=228) received no chemotherapy prior to stem cell collection. Bortezomib based regimens were the most common (78%, n=83) non-melphalan based chemotherapy. All three groups were similar in terms of median age at diagnosis (59.1 years), median age at collection (59.4 years), gender distribution (59% males, n=221) and type of involved free light chain (FLC), with lambda being more common (72.2%, n=268). Patients who received melphalan-based chemotherapy had more cardiac (73.8% vs. 45.2% vs. 46.4%, p=0.005) and renal (84.2% vs. 50.9% vs. 68%, p=0.0002) involvement compared to other chemotherapy and no chemotherapy groups, respectively. In contrast, patients who received non-melphalan based chemotherapy had higher plasma cell burden (15% vs. 6% vs. 10%, p< 0.0001) and greater difference between involved and uninvolved FLC (44.2 mg/dL vs. 13.3 mg/dL vs. 13.2 mg/dL, p< 0.0001) compared to melphalan and no chemotherapy, respectively. Median duration of melphalan based chemotherapy was shorter at 54 days (34.5 to 79.5) or estimated 2 cycles compared to 101 days (60 to 135.5) or estimated 4 cycles (p=0.0019). Despite shorter duration of chemotherapy, total stem cell yield (million CD34/kg) was lower in patients who received melphalan based chemotherapy (5.54) compared to non-melphalan based chemotherapy (8.14) or no prior chemotherapy (7.94); p<0.0001. Similarly, day one stem cell yield (million CD34/kg) was the lowest in the melphalan group (2.71), followed by other chemotherapy group (3.63) and highest in no chemotherapy group (4.84); p<0.0001. This trend persisted for average stem cell yield per collection as illustrated in table 1. Filgrastrim (GCSF) alone was the most common mobilizing agent. However, patients with any chemotherapy prior to harvesting had higher utilization of plerixafor; 26.3% (n=10) in the melphalan group and 39.6% (n=42) in the non-melphalan group compared to 11.6% (n=27) if no prior chemotherapy (p<0.0001). However, no statistically significant difference was seen for melphalan vs. non-melphalan chemotherapy groups (p=0.44). In patients who underwent ASCT (85%, n=315), median stem cell dose (million CD34/kg) was different in the melphalan (3.66), non-melphalan (4.2) and no chemotherapy groups (4.44) (p=0.047), though the difference was not statistically significant amongst the 2 chemotherapy groups (p=0.34). There was also no difference in time to engraftment (table 1). Conclusions: Melphalan based chemotherapy, even if used for a short duration of time, significantly decreases both total stem cell yield and the yield on day one. It therefore has the potential to add to resource utilization with more collections needed. As much as possible, limited cycles of melphalan based chemotherapy or non-melphalan based treatment should be utilized in patients who are transplant eligible. Disclosures Dispenzieri: GSK: Membership on an entity's Board of Directors or advisory committees; Alnylam: Research Funding; Prothena: Membership on an entity's Board of Directors or advisory committees; Jannsen: Research Funding; Celgene: Research Funding; pfizer: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding. Kapoor:Amgen: Research Funding; Takeda: Research Funding; Celgene: Research Funding. Kumar:Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Research Funding; Glycomimetics: Consultancy; BMS: Consultancy; Sanofi: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Millennium: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; Kesios: Consultancy.

Abstract Introduction: Chemotherapeutic options for patients with systemic light chain amyloidosis (AL) who are not transplant candidates include bortezomib based therapy, melphalan with dexamethasone, and less commonly, immunomodulatory drugs (IMiDs). However, prospective clinical trial data comparing these regimens are lacking. This study aims to compare efficacy of bortezomib-based treatment to other therapies. Methods: All patients with AL seen within 90 days of diagnosis at our institution over a 10-year period (2006 to 2015) who did not undergo a stem cell transplant were identified from our institutional database. Data pertaining to demographics, diagnosis, treatment and follow-up were extracted from electronic medical records. Analyses were carried out by chi-square and Fisher's exact test for categorical variables and Kruskal-Wallis and Wilcoxon rank sum test for ordinal and continuous variables. Progression free survival (PFS) is defined as time to death, progression requiring treatment change or relapse requiring re-institution of treatment. PFS and overall survival was analyzed via the Kaplan-Meier method. Results: Seven hundred and twenty five patients met the inclusion criteria, of which 38% (n=275) received bortezomib containing regimens and 62% (n=450) received non-bortezomib based therapies. Bortezomib was used with dexamethasone in 24% (n=67) patients; and with other drugs, most commonly cyclophosphamide, in 76% (n=208) patients. Non-bortezomib treatment regimens included melphalan-based treatment in the majority (92%, n=414) followed by IMiDs with steroids and other drugs (8%, n=36). Baseline variables similar in both groups and their distribution in the entire cohort was as follows: gender distribution (63.3% males, n=459), median age of diagnosis (66.3 years, range 32.2 to 93.6), type of involved free light chain (FLC) (lambda 73%, n=523) and median plasma cell burden (10%, range 0 to 91). Median difference between the involved and uninvolved free light chain (dFLC) was higher in the bortezomib group (29 mg/dL vs. 23 mg/dL; p=0.017). There was no difference in organ involvement. In the bortezomib group, organ involvement was as follows: cardiac (81%, n=219), renal (62%, n=168) and hepatic (18%, n=48). In the non-bortezomib group, the rates of organ involvement were similar: cardiac (78%, n=346), renal (57%, n=247) and hepatic (19%, n=85). Median duration of first line treatment was similar in the 2 groups, with 178 days in the bortezomib cohort and 187 days in the non-bortezomib cohort. Response rates are illustrated in Table 1. Rates of very good partial response (VGPR) or better response were higher in the bortezomib group (64 % vs. 54%, p=0.0002). Patients treated with bortezomib achieved VGPR faster with higher rates of VGPR or better response seen at 3 months (48% vs. 27%, p <0.0001) and 6 months (57% vs. 34%, p < 0.0001) after initiation of therapy compared to non-bortezomib treatment. Rates of organ response were similar amongst the 2 groups as shown in Table 1. However, median time taken to achieve a cardiac response was shorter in the bortezomib group (23 vs. 38 weeks, p=0.0026). In a multivariable model, bortezomib-based treatment and dFLC at diagnosis were predictors of VGPR. Relapse or progression requiring change in therapy was more common in patients treated with non-bortezomib based therapy (38%, n=143/372) compared to bortezomib-based treatment (28%, n=67/236); p =0.01). However, no difference in overall survival was observed in patients treated with bortezomib (2.2 years; 95% confidence interval (CI): 1.7 to 3.3) vs. non-bortezomib therapies (1.7 years; 95% CI: 1.3 to 2.5). Conclusion: Treatment with bortezomib-based regimens results in a deeper response including higher rates of early VGPR at 3 and 6 months from starting therapy. Moreover, these patients achieve cardiac response faster and have lower rate of relapse. However, no difference in overall survival was seen, which may be explained by subsequent use of bortezomib-based therapies in this population. Disclosures Dispenzieri: Celgene: Research Funding; Alnylam: Research Funding; pfizer: Research Funding; Jannsen: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Membership on an entity's Board of Directors or advisory committees; Prothena: Membership on an entity's Board of Directors or advisory committees. Kumar:Millennium: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; AbbVie: Research Funding; Janssen: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding; BMS: Consultancy; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Array BioPharma: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; Kesios: Consultancy; Glycomimetics: Consultancy.

Abstract Introduction: Hematologic response criteria for light chain amyloidosis (AL) requires that difference in involved and uninvolved free light chains (dFLC) be at least 5 mg/dL (or 50 mg/L). However, many patients do not meet these criteria and are often excluded from clinical trials. These patients are challenging to follow clinically as organ response takes much longer and therefore response to treatment is difficult to evaluate in the first few cycles. This study aims to evaluate patients who had non-evaluable FLC (dFLC< 5 mg/dL) at diagnosis and compare them to those who had evaluable FLC (dFLC≥ 5 mg/dL). Methods: All patients with newly diagnosed AL seen within 90 days of diagnosis at our institution over a 10-year period (2006-2015) were identified from an institutional database. Data pertaining to demographics, diagnosis, treatment and follow-up was extracted from electronic medical records. Analysis was carried out by chi-square and Fisher's exact test for categorical variables and Kruskal-Wallis and Wilcoxon rank sum test for ordinal and continuous variables. Progression free survival (PFS) is defined as time to progression requiring treatment change or relapse requiring re-institution of treatment or death. PFS and overall survival (OS) were analyzed via the Kaplan-Meier method. Results: Of 1336 patients meeting inclusion criteria, dFLC at diagnosis was known in 1290. 85.4% (n=1101) had dFLC ≥ 5 mg/dL, while 14.6% (n=189) had non-evaluable FLC. Median age at diagnosis (65.2 vs. 63.9 years), gender distribution (males 56.1% vs.64.8%) and involved FLC (lambda: 72.2% vs. 72.9%) was similar in FLC < 5 mg/dL and FLC ≥ 5 mg/dL group. Cardiac (38.1 vs. 76.3%, p <0.0001) and liver (10.2% vs. 16.3%, p=0.03) organ involvement were less common in patients with non-evaluable FLC (table 1). NT-ProBNP was significantly lower in the group with dFLC < 5 mg/dL in patients with and without cardiac involvement, as was Mayo cardiac stage (table 1). A trend towards less gastrointestinal (GI) involvement (17.1% vs. 24%, p=0.09) was also seen with dFLC < 5 mg/dL. In contrast, a trend towards higher renal involvement was seen in patients with dFLC < 5 mg/dL (64.6% vs. 55.9%, p=0.08), though this was not statistically significant. Median 24 hour urine protein was significantly higher in all patients (with and without renal involvement) with dFLC < 5 mg/dL compared to dFLC ≥ 5 mg/dL group (table 1). Treatment details are listed in Table 1. ASCT (autologous stem cell transplant) was utilized more commonly in patients with dFLC < 5 mg/dL compared to patients with dFLC ≥ 5 mg/dL(43.2% vs. 26.1%, p <0.0001), including ASCT alone without chemotherapy (35.4% vs. 15.3%, p <0.0001).Rates of cardiac response (53.3% vs. 50.3%, p=0.88), and time to response (27.7 weeks vs. 35.6 weeks, p=0.67), were similar in both groups. Similarly, there was no difference in rates of renal and liver response and time taken to achieve a response (table 1). In patients with evaluable FLC, hematologic response was complete response (27.3%, n=245), very good partial response (21%, n=189), partial response (18%, n=160), no response (8%, n=74), progression (2%, n=15) and not known in 26.1% (n=216). In patients who had follow up data available, 30.6% (44/144) with dFLC < 5mg/dL experienced a relapse/progression with median PFS of 4.1 years (95% confidence interval (CI): 3 to 5.7), while 34.7% (304/875) with FLC ≥ 5 mg/dL experienced a relapse/progression with median PFS of 1.3 years (95% CI 1.1 to 1.5); p<0.0001. Median OS was higher in patients with dFLC < 5 mg/dL at diagnosis at 8.3 years compared to 2.4 years in patients with dFLC ≥ 5 mg/dL (p < 0.0001) as depicted in Figure 1. Conclusions: Patients with non-evaluable FLC at diagnosis have significant differences in organ involvement and survival compared to those with FLC ≥ 5 mg/dL at diagnosis. They have less cardiac and liver involvement and a trend towards less GI involvement, which may be secondary to low serum FLC burden and consequent less organ deposition. However, a trend towards higher renal involvement was seen in dFLC < 5 mg/dL group, with significantly higher urinary protein excretion. Loss of FLC in urine may result in lower serum FLC levels in this group. Survival was significantly better in patients with dFLC < 5 mg/dL, which may be explained by less cardiac involvement, lower cardiac stage and lower median FLC at diagnosis. Disclosures Dispenzieri: GSK: Membership on an entity's Board of Directors or advisory committees; Prothena: Membership on an entity's Board of Directors or advisory committees; pfizer: Research Funding; Celgene: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Alnylam: Research Funding; Jannsen: Research Funding. Kapoor:Amgen: Research Funding; Takeda: Research Funding; Celgene: Research Funding. Kumar:Celgene: Consultancy, Research Funding; Janssen: Research Funding; Sanofi: Consultancy, Research Funding; Skyline: Consultancy, Honoraria; BMS: Consultancy; AbbVie: Research Funding; Noxxon: Consultancy, Honoraria; Amgen: Consultancy, Research Funding; Takeda: Consultancy, Research Funding.

SummaryThis study evaluated the differences in clinical features of 1077 newly diagnosed AL amyloidosis patients with renal involvement (n = 229, 21%), both cardiac and renal involvement (n = 443, 41%) and cardiac involvement (n = 405, 38%). Significant differences in dFLC (difference in involved and uninvolved light chains) were noted (renal, both, cardiac median: 83, 234 and 349 mg/l, P < 0.001). The proportion of patients with ≥ 10% bone marrow plasma cells (BMPCs) was lowest in renal only patients: 44%, 57%, 64%, respectively, P < 0.001. In a multivariate linear regression model incorporating organ involvement type and BMPCs ≥10%, organ involvement was a significant predictor of dFLC (P < 0.001). Median overall survival (OS) across the three groups was 83 vs. 19 vs. 16 months (P < 0.001) in patients not undergoing transplant and 5‐year OS in patients undergoing transplant was 90% vs. 75% vs. 64% (P = 0.007), respectively. In conclusion, renal involvement alone or renal + cardiac involvement in AL amyloidosis is associated with lower circulating light chain burden, which cannot be fully explained by BMPC burden alone. Increased sensitivity of the kidney to light chains, given significant interactions with the renal tubular system and secretion of modified light chain products may play a role in pathogenesis of renal AL amyloidosis and warrants further investigation.

Abstract We evaluated the impact of achieving a rapid response in 840 newly diagnosed multiple myeloma patients from 2004 to 2015. Rates of very good partial response (VGPR) or better were 29% (240/840) after 2 cycles of treatment, 42% (350/840) after 4 cycles of treatment, and 66% (552/840) as best response. Early responders after 2 cycles of treatment had higher rates of light chain disease, anemia, renal failure, International Staging System (ISS) stage III disease, and high-risk cytogenetics, especially t(4;14), and were more likely to have received triplet therapy and undergo transplant. Median progression-free survival (PFS) and overall survival (OS) were not different among patients with ≥VGPR and &lt;VGPR after 2 cycles (PFS, 28 vs 30 months, P = .6; OS, 78 vs 96 months, P = .1) and 4 cycles (PFS, 31 vs 29 months; OS, 89 vs 91 months, P = .9), although both were improved, with ≥VGPR as best response (PFS, 33 vs 22 months, P &lt; .001; OS, 102 vs 77 months, P = .003). On multivariate analysis stratified by transplant status, achievement of ≥VGPR after 2 cycles was not associated with improved PFS (hazard ratio [95% confidence interval]; transplant cohort, 1.1 [0.7-1.6]; nontransplant cohort, 1.2 [0.8-1.7]) or OS (transplant cohort, 1.6 [0.9-2.9]; nontransplant cohort, 1.5 [1.0-2.4]). Covariates in the model included high-risk cytogenetics, ISS stage III, triplet therapy, creatinine ≥2 mg/dL, light chain disease, and age. Although patients with high-risk disease are more likely to achieve early response, a rapid achievement of a deep response by itself does not affect long-term outcomes.