Systemic Light Chain Amyloidosis Research Articles

AL amyloidosis: an overview on diagnosis, staging system, and treatment

Systemic light-chain (AL) amyloidosis is a monoclonal plasma cell disease characterized by the deposition of amyloidogenic monoclonal light-chain fragments in organs, causing their dysfunction. Clinical manifestations could be very aspecific, but the most frequent ones are proteinuria with or without renal failure or heart failure, with the kidney and the heart being the first two involved organs. Histological diagnosis with Congo red staining is the gold standard, but typing the amyloid with immunohistochemistry or mass spectrometry of the Congo red positive tissue is necessary to establish if an AL or ATTR amyloidosis could be diagnosed. Staging AL amyloidosis before treatment could help physicians to prognosticate the disease. Recently, staging systems were set separately for different involved organs, using biomarkers. Autologous stem cell transplant after a daratumumab-based induction treatment is the cornerstone of therapy in younger and fit patients, with the goal of reaching a deep and rapid disease hematological and organ response. Novel therapies, borrowed from a therapeutical model of multiple myeloma, are studied to optimize AL amyloidosis outcomes. In this review, we make an overview of diagnostic procedures, staging system, and therapies of AL amyloidosis.

Minimal residual disease in systemic light chain amyloidosis: a systematic review and meta-analysis

PurposeMinimal residual disease (MRD) is a validated prognostic factor in several hematological malignancies. However, its role in systemic light chain (AL) amyloidosis remains controversial, and this systematic review and meta-analysis aims to fill this gap.MethodsWe searched for relevant studies on Pubmed, Embase, and Cochrane Controlled Register of Trials, nine studies involving 451 patients were included and meta-analyzed. This systematic review has been registered in PROSPERO (CRD42023494169).ResultsOur study found that in the group of patients who achieved very good partial response (VGPR) or better, MRD negativity was correlated with higher cardiac and renal response rates [pooled risk ratio (RR) = 0.74 (95% CI 0.62–0.89), 0.74 (95% CI 0.64–0.87), respectively]. Patients with MRD positivity had a higher hematologic progression rate within two years after MRD detection [pooled RR = 10.31 (95% CI 2.02–52.68)]; and a higher risk of hematologic + organ progression in the first year [pooled RR = 12.57 (95% CI 1.73–91.04)]. Moreover, MRD negativity was correlated with a better progression-free survival (PFS) [pooled hazard ratio (HR) = 0.27 (95% CI 0.17–0.45)]; but it did not significantly improve the overall survival (OS) [pooled HR = 0.34 (95% CI 0.11–1.07)].ConclusionIn AL amyloidosis, our study supports that MRD negativity correlates with higher cardiac or renal response rates and indicates a better PFS in the follow-up. However, the correlation between OS and the status of MRD is not significant.

Development and initial validation of the AL-PROfile patient-reported outcome measure in light chain (AL) amyloidosis.

To evaluate the psychometric properties of the AL-PROfile, a patient-reported outcome measure combining the Patient-Reported Outcomes Measurement Information System (PROMIS)-29, two items from PROMIS Cognitive Function, and select Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) items. Content validity was assessed through cognitive debriefing interviews of 20 patients who completed the AL-PROfile (Study 1). Study 2 involved 297 participants who completed the AL-PROfile and Medical Outcomes Study 36-item Short-Form Health Survey (SF-36). Reliability (internal consistency and test-retest reliability) and validity (convergent and discriminant validity, known groups validity by stage/organ involvement) were calculated. Study 1 participants found the AL-PROfile straightforward confirming the relevance of the included content. Some felt that certain questions were not related to their amyloidosis experience. Study 2 demonstrated acceptable internal consistency for all domains/items except PROMIS Cognitive Function and acceptable test-retest reliability for all except PROMIS Cognitive Function and PRO-CTCAE nausea. Large correlations were seen for the same domain across measures while correlations for divergent domains within a measure and different domains across different measures were small. The PRO-CTCAE items showed small to medium correlations with each other and with PROMIS and SF-36 domains. Stage was associated with physical function, fatigue, social roles, swelling, and shortness of breath scores. The AL-PROfile has acceptable reliability and validity for use in systemic light chain amyloidosis patients.

Healthcare Resource Utilization and Cost-of-Illness in Systemic Light Chain (AL) Amyloidosis in Europe: Results From the Real-World, Retrospective EMN23 Study

ObjectivesTo report healthcare resource utilization (HCRU) and safety outcomes in systemic light chain (AL) amyloidosis from the EMN23 study. Materials and MethodsThe retrospective, observational, multinational EMN23 study included 4,480 patients initiating first-line treatment for AL amyloidosis in 2004-2018 and assessed, among other objectives, HCRU and safety outcomes. HCRU included hospitalizations, examinations, and dialysis; safety included serious adverse events (SAEs) and adverse events of special interest (AESIs). Data were descriptively analyzed by select prognostic factors (e.g., cardiac staging by Mayo2004/European) for 2004-2010 and 2011-2018. A cost-of-illness analysis was conducted for the UK and Spain. ResultsHCRU/safety and dialysis data were extracted for 674 and 774 patients, respectively. Of patients with assessed cardiac stage (2004-2010: 159; 2011-2018: 387), 67.9% and 61.0% had ≥ 1 hospitalization, 56.0% and 51.4% had ≥ 1 SAE, and 31.4% and 28.9% had ≥ 1 AESI across all cardiac stages in 2004-2010 and 2011-2018, respectively. The per-patient-per-year length of hospitalization increased with disease severity (cardiac stage). Of patients with dialysis data (2004-2010: 176; 2011-2018: 453), 23.9% and 14.8% had ≥ 1 dialysis session across all cardiac stages in 2004-2010 and 2011-2018, respectively. The annual cost-of-illness was estimated at €40,961,066 and €31,904,386 for the UK and Spain, respectively; dialysis accounted for ∼28% (UK) and ∼35% (Spain) of the total AL amyloidosis costs. ConclusionsEMN23 showed that the burden of AL amyloidosis is substantial, highlighting the need for early disease diagnosis and effective treatments targeting the underlying pathology.

Cardiac MRI feature-tracking-derived torsion mechanics in systolic and diastolic dysfunction in systemic light-chain cardiac amyloidosis

To describe the myocardial torsion mechanics in cardiac amyloidosis (CA), and evaluate the correlations between left ventricle (LV) torsion mechanics and conventional parameters using cardiac magnetic resonance imaging feature tracking (CMR-FT). One hundred and thirty-nine patients with light-chain CA (AL-CA) were divided into three groups: group 1 with preserved systolic function (LV ejection fraction [LVEF] ≥50%, n=55), group 2 with mildly reduced systolic function (40%≤LVEF <50%, n=51), and group 3 with reduced systolic function (LVEF <40%, n=33), and compared with age- and gender-matched healthy controls (n=26). All patients underwent cine imaging and late gadolinium-enhancement (LGE). Cine images were analysed offline using CMR-FT to estimate torsion parameters. Global torsion, base-mid torsion, and peak diastolic torsion rate (diasTR) were significantly impaired in patients with preserved systolic function (p<0.05 for all), whereas mid-apex torsion and peak systolic torsion rate (sysTR) were preserved (p>0.05 for both) compared with healthy controls. In patients with mildly reduced systolic function, global torsion and base-mid torsion were lower compared to those with preserved systolic function (p<0.05 for both), while mid-apex torsion, sysTR, and diasTR were preserved (p>0.05 for all). In patients with reduced systolic function, only sysTR was significantly worse compared with mildly reduced systolic function (p<0.05). At multivariable analysis, right ventricle (RV) end-systolic volume RVESV index and NYHA class were independently related to global torsion, whereas LVEF was independently related to sysTR. RV ejection fraction (RVEF) was independently related to diasTR. LV global torsion performed well (AUC 0.71; 95% confidence interval [CI]: 0.61, 0.77) in discriminating transmural from non-transmural LGE in AL-CA patients. LV torsion mechanics derived by CMR-FT could help to monitor LV systolic and diastolic function in AL-CA patients and function as a new imaging marker for LV dysfunction and LGE transmurality.

Quantification of right ventricular amyloid burden with 18F-florbetapir positron emission tomography/computed tomography and its association with right ventricular dysfunction and outcomes in light-chain amyloidosis.

In systemic light-chain (AL) amyloidosis, quantification of right ventricular (RV) amyloid burden has been limited and the pathogenesis of RV dysfunction is poorly understood. Using 18F-florbetapir positron emission tomography/computed tomography (PET/CT), we aimed to quantify RV amyloid; correlate RV amyloid with RV structure and function; determine the independent contributions of RV, left ventricular (LV), and lung amyloid to RV function; and associate RV amyloid with major adverse cardiac events (MACE: death, heart failure hospitalization, cardiac transplantation). We prospectively enrolled 106 participants with AL amyloidosis (median age 62 years, 55% males) who underwent 18F-florbetapir PET/CT, magnetic resonance imaging, and echocardiography. 18F-florbetapir PET/CT identified RV amyloid in 63% of those with and 40% of those without cardiac involvement by conventional criteria. RV amyloid burden correlated with RV ejection fraction (EF), RV free wall longitudinal strain (FWLS), RV wall thickness, RV mass index, N-terminal pro-brain natriuretic peptide, troponin T, LV amyloid, and lung amyloid (each P < 0.001). In multivariable analysis, RV amyloid burden, but not LV or lung amyloid burden, predicted RV dysfunction (EF P = 0.014; FWLS P < 0.001). During a median follow-up of 28 months, RV amyloid burden predicted MACE (P < 0.001). This study shows for the first time that 18F-florbetapir PET/CT identifies early RV amyloid in systemic AL amyloidosis prior to alterations in RV structure and function. Increasing RV amyloid on 18F-florbetapir PET/CT is associated with worse RV structure and function, predicts RV dysfunction, and predicts MACE. These results imply a central role for RV amyloid in the pathogenesis of RV dysfunction.

Real-world efficacy of single-agent belantamab mafodotin in relapsed systemic AL amyloidosis.

Systemic light chain (AL) amyloidosis is a relapsing plasma cell disorder. Therapy is limited, particularly for triple-class refractory disease. We report the use of belantamab mafodotin, a BCMA-directed drug-antibody conjugate, for relapsed AL amyloidosis, including patients traditionally excluded from clinical trials. Thirty-one patients were reviewed, with a median of three prior lines of therapy. The median follow-up was 12 months (95% CI 4-19), and a median of five doses were delivered. The best haematological overall response rate was 71%, and the complete/very good partial response was 58%. Sixty-eight percent had keratopathy and improved in all. Belantamab mafodotin has high efficacy and good tolerability in patients with relapsed AL amyloidosis.

A Prospective Phase II Clinical Study of Low-Frequency Daratumumab for the Treatment of Systemic Light Chain Amyloidosis

Purpose: Systemic light chain (AL) amyloidosis is a disease caused by the misfolding of monoclonal immunoglobulins light chain to form amyloid, which is deposited in tissues and organs, resulting in structural destruction of tissues, organ dysfunction, and progressive progression. Daratumumab is a human CD38-targeting antibody that has been used for the treatment of patients with AL amyloidosis. This is a prospective, single-arm phase II clinical study designed to explore the efficacy and safety of low-frequency Daratumumab in patients with AL amyloidosis. Methods: A total of 47 patients are expected to be enrolled in this study. As of May. 01, 2023, a total of 38 patients with AL amyloidosis meeting the inclusion criteria were included. Low-frequency Daratumumab was administered at 16 mg/kg every two weeks for weeks 1-8 and every four weeks for weeks 9-24, either alone or in combination with bortezomib. The regimen may be discontinued after week 25, or Daratumumab monotherapy every eight weeks for up to two years for maintenance therapy. The efficacy of the previous treatment was assessed before each regimen of Daratumumab. Follow-up was performed every three months after treatment cessation until disease progression or death of the patient from any cause. Results: Of the included patients, 27 (71.1%) were male, with a median age of 64 years (59-71). The median number of involved organs was 2 (1-3), of which 27 (71.1%) had renal involvement, 34 (89.5%) cardiac involvement, and 6 (15.8%) hepatic involvement. 28 (73.7%) were newly diagnosed patients and 10 (26.3%) were recurrent and refractory patients. There were 25 (65.8%) Mayo 2004 stage III patients and 23 (60.6%) Mayo 2012 stage III/IV patients. The median number of treatment cycles was 5 (2-8). All patients (100%) achieved hematologic very good partial response or above (≥VGPR), of which 18 (48.6%) patients achieved hematologic complete response or above (≥CR). The median time to hematologic remission was 15.0 days (14.0-29.0 days) and the median time to hematologic CR was 92.5 days (28.0-119.3 days). 9 (40.9%) patients achieved renal remission, with a median response time of 41.0 days (29.0-87.0 days).11 (33.3%) patients achieved cardiac remission, with a median response time of 145.0 days (30.0-223.0 days). And 1 (16.7%) patient achieved hepatic remission. At a median follow-up of 11.8 months (9.8-13.7 months), median progression-free survival (PFS) and overall survival (OS) were not reached, with a 6-month PFS of 91.0% and a 6-month survival OS of 91.0%. In terms of safety, the most common adverse events were fatigue (22 cases, 57.9%), infection (18 cases, 47.4%), and fever (16 cases, 42.1%). 7 (18.4%) patients had Daratumumab-related infusion reactions. Conclusion: The results of this study showed that the low-frequency daratumumab regimen demonstrated good hematological and organ efficacy in the treatment of patients with AL amyloidosis. Patients had a high early survival rate and better safety profile.

Monitoring of Systemic Light-Chain Amyloidosis Patients Using Mass Spectrometry (M-inSight) in Serum

Introduction: Systemic light-chain amyloidosis (AL) is a rare disorder characterized by extracellular deposition of monoclonal light-chain immunoglobulins forming insoluble aggregates in different organs. Kidney, heart and liver are principal organs affected by the disease inducing dysfunctions and failures. In this disease, even a low level of circulating light chain can cause significant damages, making challenging the measure of disease burden via peripheral blood. Although a bone marrow aspiration is required to confirm the diagnosis, the evolution of the disease is usually monitored using free light chains dosage, serum and urine electrophoresis, as well as immunofixation. However, these techniques have demonstrated some limitations in terms of sensitivity. Sebia had recently introduced M-inSight TM, a novel, ultra-sensitive and non-invasive assay for monitoring low level disease on blood using targeted mass spectrometry. In this pilot study, M-inSight TM technology is employed to assess the use of mass spectrometry to monitor AL patients. Methods: 14 AL patients were selected to assess the use of M-InSight to detect and quantify AL light chain. 8/14 patients were selected from the AMYDARA study (NCT02816476), consisting in refractory patients treated with Daratumumab. Serum free light-chain assay (Freelite TM), immunofixation on serum/urine as well as bone marrow collection for DNA (ClonoSeq) and RNA (RACE-RepSeq) immunoglobulin next generation sequencing were used to monitor the disease at baseline and end of treatment (EOT) and compared to M-inSight TM. Additionally, 6/14 multicenter patients with normal free light chain level at diagnosis were selected to evaluate the sensitivity of M-InSight. Total mRNA was extracted from BM samples, retrotranscribed to cDNA and then used for immunoglobulin repertoire high-throughput sequencing assay (RACE-RepSeq). cDNA assembly pipeline using IMGT/HighV-QUEST and Vidjil software were used to construct clonotypes and to identify clonal molecular fingerprints and finally their clonotypic peptides for M-InSight analysis. This technology consists of sequence the AL light chain from serum sample and choose clonotypic peptides from the hypervariable regions which then tracked down in the follow-up sample. Results Clonotypic peptides were identified in all eight patients from the baseline sample, which were then confirmed by mass spectrometry. Out of the 8 AMYDARA patients, 5/8 patients achieved very good partial response (VGPR), 2/8 achieved partial response (PR) and 1/8 resulted in complete response (CR). 6 patients had a decrease of the dFLC ratio measure with Freelite TM of 80% or more. 6 out of these 8 patients had MS data highly concordant with that of the serum free light-chain assay. 2 patients had a strong decrease in dFLC while MS measurements were stable or increased. However, detection of the clonotype using RACE-RepSeqand Clonoseq remained elevated, which was more in line with MS than Freelite TM. All patients with normalization of their dFLC were still detected using M-inSight, even those reaching MRD negativity (1 patient) or low number of cells (~10-5, 2 patients) by ClonoSeq. These results were consistent with the RACE-RepSeq which detected the light chain clonotypes in all patients at EOT. Clonotypic peptides using M-InSight were also detected in all 7 patients with normal free light chain at diagnosis. However, in one bi-clonal patient, peptides from only one of both chains were detected, suggesting that only one clone was secreting light chain. Conclusion The goal of this study was to evaluate the M-InSight technique to monitor the evolution of systemic AL amyloidosis in blood samples. The results showed a high concordance with bone marrow MRD measurement and a higher sensitivity than dFLC to monitor the disease. This study shows that MRD monitoring on blood is feasible, using an ultra-sensitive MS technique, avoiding invasive bone-marrow aspirate. M-inSight can track low level AL disease.

Immune Checkpoint Expression Patterns on T Cell Subsets in Light-Chain Amyloidosis: VISTA, PD-1, and Tigit As Potential Therapeutic Targets

Abstract Background: Systemic immunoglobulin light chain amyloidosis (AL amyloidosis) is a rare plasma cell dyscrasia with a poor prognosis. T-cell exhaustion can lead to impaired T cell-mediated antitumor immunity, but there is limited information available regarding the T-cell immunodeficiency status in AL amyloidosis. This study aims to investigate the T-cell immune checkpoint expression patterns in AL amyloidosis and its relationship with clinicobiological characteristics. Methods: Using multi-color fluorescent flow cytometry, we examined the expression levels of V-domain immunoglobulin suppressor of T cell activation (VISTA), programmed death 1 (PD-1), T cell immunoglobulin and mucin-domain-containing-3 (Tim-3), T cell immunoreceptor with Ig and ITIM domains (TIGIT) on CD3+, CD4+, CD8+ T-cell, and regulatory T cell (Treg) in peripheral blood (PB) and bone marrow (BM) from 19 patients with newly diagnosed AL amyloidosis. We used 36 PB and BM samples from patients with newly diagnosed multiple myeloma (MM) and 19 PB and 10 BM samples from healthy individuals (HIs) as controls. Results: Our results showed that PB from patients with AL amyloidosis had significantly higher percentages of VISTA+ and PD-1+ subsets within CD3+, CD4+, CD8+ T cells and Tregs when compared to HIs. No statistical differences for frequency of VISTA+, PD-1+, Tim-3+ and TIGIT+ T-cell in BM were observed between the two groups. The percentages of double-positive VISTA+ PD-1+, VISTA+ Tim-3+, VISTA+ TIGIT+, PD-1+ Tim-3+ and PD-1+ TIGIT+ T cells in PB from the patients with AL amyloidosis were also considerably higher than those in the HIs. Moreover, we discovered that the patients with renal involvement had greater percentages of PD-1+ or TIGIT+ subsets within CD3+, CD4+ T cells and Tregs than the individuals without renal involvement. Additionally, PD-1+CD3+%, PD-1+CD4+%, and PD-1+Treg% were found to be positively correlated with 24-hour proteinuria levels. Furthermore, we observed that the AL amyloidosis patients had significantly higher counts of PD-1+ Treg in PB than the MM patients, while the MM patients had significantly higher counts of TIGIT+ subsets within CD3+, CD4+ and CD8+ T cells than the AL amyloidosis patients. Conclusions: Our findings suggest that there are elevated proportions of VISTA+ and PD-1+ T cells in PB of AL amyloidosis patients, which are indicators of an immunosuppressive milieu. The rise in PD-1+ or TIGIT+ T cells was associated with renal damage. Notably, MM and AL amyloidosis have very distinct immunosuppressive patterns based on immune checkpoint alteration. Overall, VISTA, PD-1, and TIGIT may be considered as potential targets for reversing T cell exhaustion and enhancing T cell activity in AL amyloidosis.

Proteomic Analysis of Monoclonal Plasma Cells from Plasma Cell Dyscrasias

Introduction. Novel agents including Anti-CD38 monoclonal antibodies, proteasome inhibitors and immunomodulatory drugs have improved the therapeutic outcome of plasma cell dyscrasias such as multiple myeloma (MM) and systemic light chain (AL) amyloidosis. Additionally, Next-generation sequencing (NGS) has greatly improved the ability to detect genomic aberrations occurring in monoclonal plasma cells. However, NGS data has not been made use for treatment decisions of plasma cell dyscrasias. Also, mechanisms of resistance to therapeutic agents have not been clearly shown in patient samples. Moreover, in-depth differences of monoclonal plasma cells among plasma cell dyscrasias are yet to be known. In the current study, we analyzed the protein expression in monoclonal plasma cells derived from patients with MM or AL amyloidosis by mass spectrometry to understand the biological differences in cells among those diseases and changes according to treatment. Materials and methods. Bone marrow samples from 47 newly diagnosed plasma cell dyscrasia patients (30 MM patients, 17 AL amyloidosis patients) and 9 relapsed and refractory patients diagnosed at Kumamoto University Hospital and Kumamoto Shinto General Hospital were examined. Patients provided written informed consent in accordance with the Declaration of Helsinki and the institutional ethics policy. Monoclonal plasma cells were obtained from bone marrow aspirates by CD138 magnetic beads selection. Sample preparation for proteomic analysis was performed using the PTS method, and digested peptides were desalted with SDB-XC tip. An Orbitrap Fusion Tribrid was used for peptide analysis, and peptide sequence information was acquired in data independent acquisition mode. Protein identification and quantification were performed by DIA-NN 18.1. Statistical and pathway analyses were performed using ExpressAnalyst, MetaboAnalyst and Metascape. Results. Monoclonal plasma cells from plasma cell dyscrasia patients were statistically divided into 3 groups (Group 1, 2 and 3) according to protein expression. Group 1 samples had enrichment of the Endocytosis and the MAPK signaling, while samples in Group 3 were enriched with the Ribosome pathway. Group 2 seemed to have intermediate phenotype of Group 1 and 3. All the samples in Group 1 and 50% of the samples in Group 2 were from AL amyloidosis, while majority of samples in group 3 were from MM. MM cases belonging to Group 3 tend to have higher R-ISS staging and CD56 positive monoclonal plasma cells compared to Group 2 cases. Among AL amyloidosis samples, all Group 3 cases had cardiac involvement of amyloidosis, proven by significantly higher BNP expression, while Group 2 cases tend to have kidney involvement, indicated by low serum albumin. Serial analysis of samples before and after daratumumab therapy showed reduced expression of CD38 and SLAMF7 in post treatment samples. Proteins related to focal adhesion were decreased in post-daratumumab treated samples compared to pre-daratumumab samples. Samples from carfilzomib refractory patients had higher expression of cell cycle related proteins compared to their pre-treatment samples. Conclusions. Proteomic analysis revealed differences between MM and AL amyloidosis-derived monoclonal plasma cells. While MM samples tend to belong to Group 3, which showed the activation of the Ribosome pathway, AL amyloidosis samples were mainly divided into Group 1 or 2, accompanying high enrichment of the Endocytosis and the MAPK signaling. Comparison of pre- and post-treatment samples showed distinct protein expression patterns according to therapeutic agents (daratumumab and carfilzomib). The current results may contribute to the understanding of differences between each plasma cell dyscrasias and mechanisms of resistance to therapeutic agents.

Using Next Generation Sequencing to Identify Trackable Clonotypic Sequences for Minimal Residual Disease Testing in AL Amyloidosis

Introduction: Recent studies have shown that deeper free light chain responses are associated with improved outcomes in patients with systemic light chain (AL) amyloidosis, yet the optimal long-term goal remains unclear.(N Engl J Med 2018; 378:518-528) Unlike multiple myeloma, where the role of minimal residual disease (MRD) testing is well established, in AL amyloidosis the methods to best identify MRD, and whether achieving MRD would benefit disease outcomes, warrant further investigation. (Blood Cancer J. 2021 Jun 21;11(6):117; PLoS ONE 15(7): e0235713. https://doi.org/10.1371/journal.pone. 0235713) In AL amyloidosis, the toxic misfolded oligomers and amyloid deposits are both due to clonal immunoglobulin light chains and cause organ damage and death. Hence, the tracking of clonotypic light chain sequences could present a promising approach for detecting the maintenance of profound therapeutic responses. Our study aimed to assess the frequency with which next generation sequencing (NGS) detects light-chain clones consistent with the patient's clonal light-chain isotype and to determine whether the light-chain sequences identified were encoded by light-chain variable region genes considered AL-related.(Journal of Clinical Oncology 2019 37:15_suppl, 8010; Blood (2017) 129 (3): 299-306; PLoS One 2022 Feb 25;17(2):e0264407) Methods: Ninety patients diagnosed with AL amyloidosis between September 2016 and July 2023 at Tufts Medical Center and University of California San Francisco were included. Bone marrow samples from the 90 patients were sent to Adaptive Biotechnologies Inc. (Seattle, WA) for initial clone identification using the clonoSEQ Assay. IMGT/BlastSearch database (Version 1.2.1) was used to identify the clonotypic immunoglobulin light chain variable domains detected by the clonoSEQ assay. Samples were then divided in to two groups based on the consistency of paraprotein isotype with the trackable sequences, and Mann-Whitney U test was used to compare the difference of the numbers of clonotypic sequences. Results: Of the 90 patients with bone marrow samples sent for clone identification, 85 (94.4%) had at least one trackable clonotypic sequence, with a median number of 3 and a maximum of 11. Of the 85 patients with trackable sequences, 67 (78.8%) had an AL paraprotein isotype consistent with the detected clonotypic sequence isotype, 48 with light chain and 19 with heavy chain isotypes. Compared to the inconsistent ones, patients who had consistency in paraprotein and trackable sequences exhibited higher numbers of clonotypic sequences ( P = 0.001). With respect to marrow plasma cell infiltrations, both consistent and inconsistent groups had a median of 15% marrow plasma cells with no statistically significant difference between them by two-tailed Mann-Whitney. Of note, consistent with the restricted pattern of germline gene use in AL, the 48 patients also used AL-related variable region Ig light chain genes; the variable region light chain genes identified were AL-related and included IGKV1-33 (8 identified sequences), IGKV4-1 (4), IGKV1-16 (3), IGKV1-5 (1), GKV1-13 (1), IGLV6-57 (8), IGLV3-21 (6), IGLV1-44 (5), IGLV3-1 (4), IGLV1-40 (3), IGLV2-14 (3), IGLV1-51 (2). Conclusion: In patients with AL amyloidosis, the ClonoSEQ assay can identify a sequence consistent with the patient's light or heavy chain isotype almost 80% of the time. Of those cases in which a clonal light chain sequence was consistent with the patient's isotype, the genes identified were from the well described AL-related light chain variable region gene repertoire. These findings indicate that the size of the AL clone does not affect this outcome and suggest that other factors related to the adaptive immune dysregulation of AL or to the multiplex PCR process may be involved. ClonoSEQ can identify trackable clonotypic light chain sequences that are AL-related 56% of the time in patients with AL, a finding that may be relevant to patients with myeloma.

Reduced Early Mortality with Daratumumab-Based Frontline Therapy in Systemic AL Amyloidosis- Experience from the Columbia Amyloidosis Multidisciplinary Program

Introduction: Despite advances in treatmentof systemic light chain (AL) amyloidosis, early mortality (EM) has been substantial up until recently, with a 6-month EM rate of approximately 25% in the era preceding daratumumab (Muchtar et al. Blood. 2017).Daratumumab in combination with bortezomib, cyclophosphamide and dexamethasone (Dara-VCD) is the first FDA-approved therapy for systemic AL amyloidosis based on the ANDROMEDA trial with an unprecedented hematologic complete response (Heme-CR) rate ≈ 50%. However, data on hematologic and cardiac organ response rate and estimated early mortality (EM) in different stages since routine introduction of daratumumab-based frontline therapy are lacking. Methods: We performed a retrospective cohort study of all consecutive patients treated with daratumumab-based combination therapy at Columbia Amyloidosis Multidisciplinary Program (CAMP). Hematologic and cardiac organ response rates are reported on an intention-to-treat (ITT) basis, with patients who died prior to response evaluation or those with missing data classified as non-responders. Time-to-event analyses were performed by the Kaplan-Meier method. Results: Eighty-three consecutive patients treated with daratumumab-based frontline therapy were included in the analysis. The baseline characteristics of our cohort in comparison with Dara-VCD arm of ANDROMEDA is shown in Table 1. The median age at diagnosis was 68 years (range, 40-91), with 65% being males and 13 patients (16%) of Black/African-American race. The median dFLC (involved - uninvolved) was 21.9 mg/dl, with 61% of patients having baseline dFLC&amp;gt;18 mg/dl. Mayo 2004 stage IIIa/IIIb comprised 65% of our cohort compared to 37% of ANDROMEDA trial. Thirty-three patients (44%) had NYHA Class III/IV symptoms. The daratumumab-based frontline regimens used were Dara-VCD (n=78), Dara-VD (n=2), Dara-D (n=2), and Dara-Ixazomib-D (n=1). High-dose melphalan followed by autologous hematopoietic cell transplantation (HDM-AHCT) as a part of frontline therapy was performed in 11 patients (13.4%), with melphalan dose being 140 mg/m 2 in 8, 200 mg/m2 in 2, and 100 mg/m 2 in 1 patient. Hematologic response was evaluable in 78 patients (i.e. dFLC&amp;gt;2 mg/dl at diagnosis). On an ITT basis, Heme-CR was achieved by 39 patients (50%), and very good partial response or better (Heme ≥VGPR) by 57 patients (73.1%). The median time to Heme-CR from treatment initiation was 2.7 months (range, 0.42-13.97). Among patients evaluable for cardiac organ response (i.e. NT-proBNP≥650 pg/ml; n=64), 35 (58.3%) achieved an organ response. The median time to initial cardiac response (&amp;gt;30% reduction in NT pro-BNP with absolute reduction of &amp;gt;300 pg/ml) was 2.95 months (range, 0.43-10.43). Figure 1 demonstrates comparable hematologic and numerically higher cardiac organ response rate in our cohort vs Dara-VCD arm of ANDROMEDA trial. Next, we estimated the EM rate. The estimated EM at 6 months in our cohort was 7.6% (95% CI, 3.4-15.9). 6-month EM in patients with Mayo 2004 stage IIIb was 22.2% (95% CI, 9.5-43.6) vs 1.96% (95% CI, 0.27-12.65) in those with stage I-IIIa ( p&amp;lt;0.001) [Figure 2]. By Mayo 2012 staging, the estimated 6-month EM rate in patients with stage I, II, III, and IV disease was 0% (95% CI, 0-0), 0% (95% CI, 0-0), 9.6% (95% CI, 2.4-31.3), and 12.9% (95% CI, 4.9-29.8) respectively ( p=0.0425). Among patients who underwent upfront HDM-AHCT (n=11), there was no transplant-related mortality at 100 days. On evaluating the prognostic impact of individual factors in Mayo 2012 staging (NT-proBNP, Troponin, and dFLC) on OS, dFLC&amp;gt;18 mg/dl was no longer a significant adverse prognostic factor for survival in both univariate and multivariate analysis. Updated data will be presented at the meeting. Conclusion: Despite a sicker population with more advanced cardiac involvement compared to ANDROMEDA trial, daratumumab-based frontline induction therapy led to similar Heme-CR rate and favorable cardiac organ response rate in our cohort. Additionally, estimated 6-month EM has decreased by approximately 3-fold compared to historical data, with dramatic reduction in Mayo 2004 stage I-IIIa and continued substantial EM in stage IIIb disease. Finally, as clone-directed therapy has significantly improved, light chain burden at baseline may not be a relevant prognostic factor in contemporary era and should be scrutinized in larger datasets to re-design the staging system.

Limited Utility of Mayo 2012 Cardiac Staging System for Risk Stratification of Patients with Advanced Cardiac AL Amyloidosis - Analysis of a Uniformly Treated Cohort of 1275 Patients

Introduction: Systemic light chain (AL) amyloidosis is a rare incurable disorder caused by extracellular deposition of misfolded light chain protein fibrils causing organ dysfunction. Cardiac involvement is present in approximately two thirds of cases at diagnosis. Survival depends largely on the severity of cardiac involvement as well as haematological response to treatment. Two validated cardiac staging systems, Mayo 2012 (stage I-IV) (Kumar, Dispenzieri et al. 2012) and European modification of the standard Mayo staging system 2004 (stage I-IIIb) (Wechalekar, Schonland et al. 2013, Palladini, Sachchithanantham et al. 2015), stratify patients according to different thresholds of biomarkers markers of disease involvement (NTproBNP, troponin T and, additionally for Mayo 2012, difference between involved and uninvolved free light chain [dFLC]). Patients included in these original models were not treated with a uniform induction protocol and treated with regimens such as oral melphalan dexamethasone, which are now rarely used. There is a need to re-assess the predictive performance and robustness of these staging systems with current treatment approaches. We report here the comparison of cardiac staging in a large cohort of patients with AL amyloidosis uniformly treated bortezomib-containing regimens in the first-line setting from the ALChemy study. Methods: Patients enrolled in a prospective observational study at the United Kingdom National Amyloidosis Centre from 2010-2019 treated with bortezomib-based regimens were analysed. Outcomes were stratified according to Mayo 2012 and the European modified Mayo classification. Written consent was obtained from all patients in accordance with the Declaration of Helsinki. Results: 1275 patients (755 male, 520 female) were included. Median age at presentation was 67 years (range 29-89), with a median of two involved organs (range 1-5); 812 (64%) had cardiac involvement, 892 (70%) had renal and 154 (12%) liver involvement. All patients were treated with first-line bortezomib-based therapy: bortezomib-cyclophosphamide-dexamethasone in 1190 [93%]; bortezomib-dexamethasone in 48 [4%]; bortezomib-thalidomide-dexamethasone in 21 [2%] and 16 others. None were treated with a daratumumab based combination or autologous stem cell transplant (ASCT) upfront; 95 (7%) had ASCT at a subsequent line of therapy. Patients were classified by Mayo 2012 staging as: stage I, II, III, IV in 199 (16%), 329 (26%), 413 (32%) and 334 (26%) cases, respectively and by European modified staging as: stages I, II, IIIa and IIIb in 219 (17%), 436 (34%), 424 (33%) and 196 (15%), respectively. The median follow-up was 47 months (95% CI 45-50), median overall survival (OS) was 59 months (95% CI 51-67) and 3-year OS was 59% (95% CI 56-61). Whilst both Mayo 2012 and European modification models were predictive of overall survival, the European modification discernibly discriminated those with the poorest and best outcomes. Median OS by European staging for stage I, II, IIIa, IIIb was: not reached (NR), 76, 34 and 8 months respectively, compared with Mayo 2012 stage I, II, III, IV: NR, 74, 36, and 26 months respectively. European stage II, IIIa, IIIb had a hazard ratio (HR) for death of: 2.42 (95% CI 1.69-3.49), 4.65 (95% CI 3.27-6.61) and 9.18 (95% CI 6.36-13.25), respectively. Mayo stage II, III, IV had a HR of: 2.54 (95% CI 1.72-3.76), 4.66 (95% CI 3.21-6.76) and 5.99 (95% CI 4.12-8.71), respectively. Conclusion: Advanced stage cardiac involvement remains a prognostic predictor of adverse outcomes. In a cohort of bortezomib-treated patients, the European modification has a stronger predictive value for poorer outcome. The Mayo 2012 staging, utilising additional dFLC, did not discriminate the most advanced disease as well suggesting that treatment markedly impacts the predictive capability of cardiac staging systems. Daratumumab-based treatments may have an even greater impact in ameliorating the adverse prognostic significance of high presenting dFLC. Until cardiac staging is revalidated for the modern treatment era of AL amyloidosis, our data should be taken into consideration when using cardiac staging systems in the clinic as well as for clinical trial design.

Clinical Characterization of Hepatic Light Chain Amyloidosis in the Chinese Population: A Single-Center Retrospective Analysis

CONCLUSION Hepatic light chain amyloidosis is caused by malignant plasma cells that abnormally secrete immunoglobulin light chains, which undergo a conformational change to a β-pleated sheet configuration and are deposited in the liver. The amyloid fibrils are deposited mainly in the hepatic sinusoids, the space of Disse and the walls of blood vessels. Previous autopsy studies have shown that the proportion of systemic light chain amyloidosis with liver involvement is extremely high; however, there are fewer systematic analyses of the clinical features in the Chinese population. Therefore, this study retrospectively analysed the clinical data of patients with hepatic lightchain amyloidosis in our center to further explore the clinical characteristics of this disease. A total of 40 patients with hepatic light chain amyloidosis were included in the analysis from 2007 to 2022. Inclusion criteria were positive liver tissue biopsy or positive biopsy of other organs with alkaline phosphatase (AKP) greater than 1.5 times the upper limit of normal or total liver span &amp;gt;15 cm in the absence of heart failure. The median age of these patients was 58±10 years and 80% were male. Of these 40 patients, 66% had light-chain amyloidosis secondary to myeloma and the remainder had primary amyloidosis. The proportion of patients with symptoms related to liver injury as the initial clinical presentation was 33%. Symptoms included malaise, abdominal distention, or jaundice. 40% of patients with symptoms related to abnormal heart function, such as chest tightness, severe shortness of breath, and dizziness. 25% of the patients were first seen for symptoms related to impaired renal function, such as proteinuria with lower limb edema or hypourocrinia. κ-type was found in 28% of the patients and λ-type in 73%. All patients had other sites of involvement, 95% with cardiac involvement (72.9%, Mayo 2004 stage III) and 48% with renal involvement. AKP was elevated in 100% of patients, r-GT in 95%, liver enzymes in 33%, total bilirubin in 44%, and the maximum anteroposterior diameter of the right lobe of the liver was 16.6±1.7 cm (upper limit of normal was 10 cm). In this cohort of patients, 80% received a 2- to 3-drug combination regimen based on proteasome inhibitors and 5% received a 2-drug combination regimen based on melphalan, with a median survival time of 6.5±31.3 months, and patients with a normal total bilirubin level had an overall survival time 2.4 times longer than those with an elevated level (p&amp;lt; 0.05,Figure 1). Contrary to previous reports of hepatic light chain amyloidosis, λ light chain amyloidosis was predominant in our center; elevated total bilirubin was an independent risk factor for survival.

Patterns of CS1 Expression on Natural Killer Cells and Correlated Factors in Plasma Cell Dyscrasias

Abstract BackgroundCS1 is overexpressed on myeloma cells, making it a promising target for immunotherapy in plasma cell dyscrasias (PCDs). However, monoclonal antibody (mAb) targeting CS1 showed limited efficacy when used alone. In addition, few clinical data of anti-CS1 chimeric antigen receptor T cell (CAR-T) have been published to date, suggesting that there may be some barriers to CS1-targeted immunotherapy. From previous studies, CS1 is expressed on some normal lymphocytes and plays an immunomodulatory role, and NK cells in particular play an important role in CS1-mediated immunity against MM. However, there are few studies on CS1 expression by NK cells in patients with plasma cell disease. Therefore, we investigated the expression of CS1 on NK cells, normal lymphocytes, and plasma cells in plasma cell dyscrasias and examined factors related to the CS1 expression level of NK cells and its relationship to survival. Methods Between January 2018 and September 2019, a retrospective analysis was performed in 236 patients with multiple myeloma (MM) and 30 patients with other PCDs, including systemic light chain amyloidosis (AL), monoclonal gammopathy of undetermined significance (MGUS), POEMS syndrome, and monoclonal gammopathy of renal significance (MGRS). CS1 expression levels in NK cells, lymphocytes, and monoclonal plasma cells were assessed in patients with plasma cell dyscrasias. Membrane-bound CS1 of these three cell types was measured by multiparameter flow cytometry. Associations of CS1 expression with clinical and laboratory features were determined by univariate and multivariate analyses. Correlations between CS1 expression and survival were computed using the Cox proportional hazards regression and by plotting Kaplan-Meier survival plots. Results When subgroups of MM and other PCDs were compared, there were no significant differences in CS1 expression in lymphocytes and NK cells alone. MM Patients had significantly higher CS1 expression levels in monoclonal plasma cells than other PCDs patients. In both MM and other PCDs patients, CS1 expression was significantly higher on monoclonal plasma cells than on NK cells and lymphocytes. There was a significant correlation between CS1 expression of monoclonal plasma cells (r = 0.60; P &amp;lt; 0.001) and that of NK cells (r = 0.79; P &amp;lt; 0.001) on univariate and multivariate analysis(Figure 1). Factors such as cytogenetic abnormalities, disease progression, or survival were not associated with CS1 expression level on NK cells. Neither CS1 expression level of monoclonal plasma cells nor that of NK cells was an independent predictor of patient survival. Conclusion We demonstrated that CS1 expression level in NK cells is consistent in plasma cell dyscrasias. CS1 expression in NK cells positively correlates with that in clonal plasma cells. This positive correlation may have implications for the development of immunotherapy targeting CS1.

Single-Center Experience of Carfilzomib-Based Combinations for Patients with Lymphoplasmacytic Lymphoma

Single-Center Experience of Carfilzomib-based Combinations for patients with Lymphoplasmacytic Lymphomas Background Use of bortezomib in Waldenstrom macroglobulinemia (WM) produces a response rate of 60-70% in treatment naïve or relapsed WM(Dimopoulos et al., 2005)(Chen et al., 2006). However, it is associated with an increased risk of peripheral neuropathy (PN). This is important considering that WM can be associated frequently with PN. Carfilzomib(K) is a second-generation proteasome inhibitor that is associated with a lower PN risk and offers a PN-sparing approach for treatment for patients(pts) with WM. In the CARD trial, K-based combinations produced a high ORR with a tolerable safety profile(Treon et al., 2014). We report our single-center experience with the use of K-based combinations in pts with treatment naïve or relapsed lymphoplasmacytic lymphoma (LPL). Patients and Methods We conducted a single-center retrospective study on an IRB-approved protocol for all pts who were treated with K-based combinations at Hackensack University Medical Center between June 2015 and July 2022. Demographic characteristics, molecular studies, treatment and response information were recorded and included in the study. Efficacy outcomes included overall response rates (ORR), progression free survival (PFS), overall survival (OS). Survival analysis was performed using the Kaplan-Meier method including PFS and Overall survival (OS). PFS was defined as time from initiation of treatment to progression of disease or death whichever occurred first. OS was defined as time from initiation of treatment to death. The consensus criteria from the 6 th International Workshop on WM were utilized for response assessment. Results We identified 36 patients with a diagnosis of WM and 1 patient with IgA-kappa LPL who were treated with K-based combinations between June 2015 and July 2022. 4 patients (10.8%) had a concomitant diagnosis of systemic light chain amyloidosis (AL). 67.6% pts were male, the median age at treatment initiation was 67.5 yrs. Majority of the pts were treatment naïve (86.4%, N=32). Data for MYD88 mutation was available in 30 pts, 93.3% (n=28) were found to have MYD88 mutation on next generation sequencing (NGS) performed on bone marrow aspirate samples. As per the RPISSWM risk stratification, 30% (9) pts were found to have poor risk, 33.3% (10) had intermediate risk and 36.7% (11) had good risk. Median bone marrow involvement by WM was 30%. The majority of the pts (91.9%, n=34) received KCD-R (Carfilzomib, cyclophosphamide, dexamethasone and rituximab) as their treatment regimen, while the remaining patients received KD-R(carfilzomib, dexamethasone and rituximab). Pts received a median of 6 cycles of treatment. ORR was found to be 97.3% (n=36) with 48.6%(n=18) pts achieving a very good partial response or better (&amp;gt;=VGPR). Median PFS was found to be 51.08 months and median OS was not reached (NR). Two patients needed treatment discontinuation following 1 cycle or less, due to toxicity (dyspnea, one of which was non-cardiogenic) associated with carfilzomib and were changed to an alternative regimen (Bortezomib, cyclophosphamide, dexamethasone and rituximab). Further data for toxicities are being gathered and will be presented at the meeting. Baseline characteristics and outcomes data are summarized in Table 1. Conclusions K-based combinations produce a high ORR with durable responses in patients with symptomatic LPL. Treatment discontinuation rate due to toxicity was low with only two patients needing change of therapy in our cohort. Our data supports the use of K-based combinations in pts with treatment naïve or relapsed LPL.

[Efficacy and safety analysis of a combination regimen with BCL-2 inhibitor in relapsed/refractory primary systemic light chain amyloidosis with t(11;14) from a single center].

Objective: To explore the efficacy and safety of BCL-2 inhibitor-based treatment in patients with relapsed/refractory t (11; 14) primary systemic light chain amyloidosis. Methods: This was a retrospective case series study. Ten patients with relapsed/refractory t(11;14) primary systemic light chain amyloidosis who had all received treatment with a combination regimen including the BCL-2 inhibitor venetoclax from January 2018 to November 2022 at the Hematology Department of Peking University People's Hospital were included. Adverse events, and hematological and organ responses were evaluated. Results: The median age of the ten enrolled patients was 59 (range 41-78) years, and the male to female ratio was 8∶2. Except for one patient, a very good partial or better response was achieved in 8/9 patients and one patient obtained a partial response. The overall response rate was 100%. The median time to achieve a hematological response was 60 (range 24-236) days. At least one organ response was observed in 7/9 patients. With a median follow-up of 18 months, one patient experienced hematological progression and one patient died. Grade 3 adverse events included lymphocytopenia (3 cases), anemia (1 case), diarrhea (1 case), and appendicitis (1 case). One patient died of pulmonary fungal infection two months after completion of treatment, which was not excluded as being treatment related. Conclusion: A combination regimen including BCL-2 inhibitors in patients with relapsed/refractory t(11;14) primary systemic light chain amyloidosis is a potentially safe and effective treatment option that warrants further investigation.

Systemic light chain amyloidosis: the hope for a cure

Systemic light chain amyloidosis: the hope for a cure

Peripheral Nervous, Hepatic, and Gastrointestinal Endpoints for AL Amyloidosis Clinical Trials: Report from the Amyloidosis Forum Multi-organ System Working Group.

Systemic immunoglobulin light chain (AL) amyloidosis is a heterogeneous rare disease driven by a destructive monoclonal gammopathy and typified by misfolded immunoglobulin light and/or heavy chains which aggregate and deposit in organs as insoluble amyloid fibrils. Disease heterogeneity is driven by the degree of multi-systemic involvement; cardiac, renal, neurological, and gastrointestinal (GI) systems are affected to varying degrees in different patients. While prognosis is primarily driven by hematologic response to treatment and outcomes associated with cardiac events and overall survival, the involvement of the peripheral nervous, hepatic, and GI systems can also have a significant impact on patients. The Amyloidosis Forum ( https://amyloidosisforum.org ) is a public-private partnership between the nonprofit Amyloidosis Research Consortium ( www.arci.org ) and the US Food and Drug Administration (FDA) Center for Drug Evaluation and Research formed to advance drug development for the treatment of systemic amyloid disorders. A series of virtual workshops focused on the development of novel, patient-relevant endpoint components and analytical strategies for clinical trials in AL amyloidosis. This review summarizes the proceedings and recommendations of the Multi-Systemic Working Group which identified, reviewed, and prioritized endpoints relevant to the impacts of AL amyloidosis on the peripheral nervous, hepatic, and GI systems. The Working Group comprised amyloidosis experts, patient representatives, statisticians, and representatives from the FDA, Medicines and Healthcare products Regulatory Agency (MHRA), and pharmaceutical companies. Prioritized neuropathy/autonomic endpoints included a modified form of the Neuropathy Impairment Score (NIS + 7) and the Composite Autonomic Symptom Score (COMPASS-31), respectively. Alkaline phosphatase was identified as the most relevant indicator of liver involvement and disease progression. Following extensive review of potential GI endpoints, the Working Group identified multiple exploratory endpoints. These recommended components will be further explored through evaluation of clinical trial datasets and possible integration into composite endpoint analysis.