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

OBJECTIVES: To report healthcare resource utilization (HCRU) and safety outcomes in systemic light chain (AL) amyloidosis from the EMN23 study. MATERIALS AND METHODS: The 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. RESULTS: HCRU/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. CONCLUSIONS: EMN23 showed that the burden of AL amyloidosis is substantial, highlighting the need for early disease diagnosis and effective treatments targeting the underlying pathology.

Detection of serum M-protein in acetonitrile precipitates by MALDI-TOF mass spectrometry: A novel, low-cost methodology.

BACKGROUND: Several studies have demonstrated the analytical sensitivity of MALDI-TOF mass spectrometry (MALDI-TOF MS) by immunoenrichment for M-protein analysis. We report the results of a novel, low-cost, reagent-based extraction process using acetonitrile (ACN) precipitation to enrich for κ and λ light chains which can be analysed by MALDI-TOF MS. METHODS: Institutional Ethics committee approval was obtained. Serum samples from patients with monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma (MM), plasmacytoma, AL amyloidosis and Waldenström macroglobulinemia (WM) underwent ACN precipitation. The images obtained were overlaid on apparently healthy donor serum samples to confirm the presence of M-protein. A sample was considered positive for M-protein if there was a sharp or broad peak within the κ or λ mass/charge (m/z) range: m/z- [M + 2H]2+: 11,550-12,300 Da and λ m/z- [M + 2H]2+: 11,100-11,500 Da. Images were acquired at a m/z range of 10,000-29,000 Da. Corresponding serum protein electrophoresis (SPEP), serum immunofixation electrophoresis (IFE) and serum free light chain (sFLC) assay by nephelometry were performed for all the samples. RESULTS: Two-hundred-and-two serum samples were included in the study: MM- 184 (91%); AL amyloidosis- 2 (1%); plasmacytoma- 8 (4%); MGUS- 6 (3%) and WM- 2 (1%). All the SPEP positive samples were identified by MALDI-TOF MS. Out of 179 samples positive for M-protein by IFE, MALDI-TOF MS was positive in 176 samples (98%). Compared to IFE, the sensitivity and specificity of M-protein identification by MALDI-TOF MS were 98.3% and 52.2%, respectively. CONCLUSIONS: This study demonstrates the feasibility of qualitatively identifying M-protein without the need for antibody-based immunoenrichment, making the technique cost-effective.

Immunoglobulin Light Chain Amyloidosis: Diagnosis and Risk Assessment.

Immunoglobulin light chain (AL) amyloidosis is a clonal plasma cell disorder with multiple clinical presentations. The diagnosis of AL amyloidosis requires a high index of suspicion, making a delay in diagnosis common, which contributes to the high early mortality seen in this disease. Establishing the diagnosis of AL amyloidosis requires the demonstration of tissue deposition of amyloid fibrils. A bone marrow biopsy and fat pad aspirate performed concurrently have a high sensitivity for the diagnosis of AL amyloidosis and negate the need for organ biopsies in most patients. An accurate diagnosis requires amyloid typing via additional testing, including tissue mass spectrometry. Prognostication for AL amyloidosis is largely driven by the organs impacted. Cardiac involvement represents the single most important prognostic marker, and the existing staging systems are driven by cardiac biomarkers. Apart from organ involvement, plasma cell percentage on the bone marrow biopsy, specific fluorescence in situ hybridization findings, age at diagnosis, and performance status are important prognostic markers. This review elaborates on the diagnostic testing and prognostication for patients with newly diagnosed AL amyloidosis.

State-of-the-art review on AL amyloidosis in Western Countries: Epidemiology, health economics, risk assessment and therapeutic management of a rare disease.

Amyloidosis is the term to define a broad array of rare protein misfolding syndromes. Among them, light chain (AL) amyloidosis is the most common, affecting roughly 10 people per million/year. The core purpose of the present literature review is to shed light on the academic and clinical knowledge on the condition, encompassing its i) epidemiology, ii) economic burden, and iii) quality of life consequences. The areas of interest are Europe and North America. Literature search was primarily performed on Embase® and finally integrated with additional, deemed eligible, sources. Pre-defined PICOS criteria were employed for the inclusion and exclusion processes. A total of 64 studies were comprehensively included in the current literature review as compliant with the inclusion criteria. The results were presented according to the outcomes of interest and eventually triangulated and compared to available literature studies. A broad picture on the main aspects of AL amyloidosis is delivered.

Real-world treatment patterns, costs, and outcomes in patients with AL amyloidosis: analysis of the Optum EHR and commercial claims databases.

BACKGROUND: This study characterised real-world treatment patterns, clinical outcomes, and cost-of-illness in patients with light-chain (AL) amyloidosis. METHODS: Data were extracted from the US-based Optum® EHR and Clinformatics® Data Mart (claims) databases (2008-2019) for patients newly diagnosed with AL amyloidosis and who initiated anti-plasma cell therapies. Healthcare resource utilisation (HCRU) and related costs were compared across lines of therapy (LOT). Incidences of cardiac and renal failure were evaluated using the Kaplan-Meier method. RESULTS: About 1347 patients (EHR, n = 776; claims, n = 571) were included. Median age was 68 years; 56.8% were male. At initial diagnosis, 33.1% and 15.1% of patients had cardiac and renal failure, respectively. Most patients received bortezomib-containing treatment in LOT1 (69%); bortezomib-cyclophosphamide-dexamethasone was most common (26%). HCRU was similar across LOTs. Mean per-patient-per-month and per-patient-per-LOT costs were $19,343 and $105,944 for LOT1, $19,183 and $95,793 for LOT2, and $16,611 and $128,446 for LOT3, respectively. Costs were primarily driven by anti-plasma cell therapies, outpatient visits, and hospitalisations. The 5-year cardiac and renal failure rates following initial diagnosis were 64.5% and 39.0%, respectively. CONCLUSION: AL amyloidosis is associated with substantial costs and suboptimal outcomes, highlighting the need for new therapeutic approaches to prevent organ deterioration, and reduce disease burden.

Diagnostic amyloid light chain amyloidosis hospitalizations associated with high acuity and cost: analysis of the Premier Healthcare Database.

Aim: Estimate the frequency and costs of diagnostic admissions among hospitalized patients with amyloid light chain (AL) amyloidosis. Materials & methods: This retrospective analysis used nationally representative hospital discharge data from 2017 to 2020 to report resource use and cost for hospitalizations during which AL amyloidosis was diagnosed. Results: Of 1341 admissions, 17.6% were diagnostic. Bone marrow (79.5%) and kidney (44.9%) biopsies were the most common qualifying biopsies. Diagnostic hospitalizations had longer length of stay (14.5 vs 8.4 days; p < 0.001) and higher cost ($40,052 [USD] vs $24,360; p < 0.001) than nondiagnostic ones. Conclusion: Diagnostic admissions are more likely to be urgent/emergent, require longer stays and have higher costs compared with hospitalizations in known AL amyloidosis patients. Improved diagnostic pathways toward early diagnosis are needed.

Systematic literature review of evidence in amyloid light-chain amyloidosis.

Introduction: Treatment of amyloid light-chain (AL) amyloidosis, a rare disease with a <5-year lifespan, remains challenging. This systematic literature review (SLR) aimed to evaluate the current evidence base in AL amyloidosis. Methods: Literature searches on clinical, health-related quality of life, economic and resource use evidence were conducted using the Embase, MEDLINE and Cochrane databases as well as gray literature. Results: This SLR yielded 84 unique studies from: five randomized controlled trials; 54 observational studies; 12 health-related quality of life studies, none with utility values; no economic evaluation studies; and 16 resource use studies, none with indirect costs. Conclusion: This SLR highlights a paucity of published literature relating to randomized controlled trials, utility values, economic evaluations and indirect costs in AL amyloidosis.

Prospective urinary albumin/creatinine ratio for diagnosis, staging, and organ response assessment in renal AL amyloidosis: results from a large cohort of patients.

OBJECTIVES: Quantification of 24 h-proteinuria is the gold standard for diagnosing, staging, and monitoring of patients with renal AL amyloidosis. However, 24 h-urine collection is cumbersome and may result in preanalytical error. In this prospective study, we investigated the role of urinary albumin/creatinine ratio (UACR) (cut-off: 300 mg/g) identifying renal involvement, evaluated a UACR-based staging system (UACR cut-off: 3,600 mg/g) and assessed whether UACR response (UACR decrease >30% without worsening in eGFR >25%) predicts renal outcome in 531 patients with newly-diagnosed AL amyloidosis. METHODS: From October 2013 paired 24 h-proteinuria and UACR (on first morning void) were measured in all newly-diagnosed patients with AL amyloidosis. Correlation between 24 h-proteinuria and UACR at baseline was assessed by Pearson's r test. Impact of UACR response on renal outcome was assessed in randomly created testing (n=354) and validation (n=177) cohorts. RESULTS: A strong linear correlation was found between 24 h-proteinuria and UACR at baseline (r=0.90; p<0.001). After a median follow-up of 31 months, 57 (11%) patients required dialysis. A UACR-based renal staging system identified three stages with significantly higher dialysis rate at 36 months comparing stage I with stage II and stage II with stage III. Achieving a renal response, according to a UACR-based criterion, resulted in lower dialysis rate in both testing and validation cohorts. CONCLUSIONS: UACR is a reliable marker for diagnosis, prognosis, and organ response assessment in renal AL amyloidosis and can reliably replace 24 h-proteinuria in clinical trials and individual patients' management.

The role of induction therapy before autologous stem cell transplantation in low disease burden AL amyloidosis patients.

BACKGROUND: Induction therapy is recommended before autologous stem cell transplantation (ASCT) for AL amyloidosis patients with high disease burden [bone marrow plasma cells (BMPCs) > 10%], but the role of induction therapy before ASCT in patients with low disease burden (BMPCs ≤ 10%) is still unknown. METHODS: A total of 227 patients with AL amyloidosis were included in this study. Among 227 patients, 124 patients received bortezomib-based induction prior to ASCT and were defined as group A, 35 patients received other chemotherapeutic induction and were defined as group B, and the other 68 patients without induction were defined as group C. We compared the differences of efficacy and prognosis between the three groups. RESULTS: The haematological overall response rates (ORR) of groups A, B and C were 91%, 67% and 75%, respectively. The complete response rates (CR) of groups A, B and C were 50%, 25% and 20%, respectively. Both the ORR and CR rates of group A were significantly higher than those of groups B and C. The renal response rates of groups A, B and C were 64%, 46% and 47%, respectively. The cardiac response rates of groups A, B and C were 74%, 45% and 40%, respectively. The renal and cardiac responses rates of group A were also significantly higher than those of the other two groups. After a median follow-up of 44 months, the median OS was not reached. The 5-year estimated overall survival (OS) rates of groups A, B and C were 81%, 57% and 67%, respectively. The median progression-free survival (PFS) was 83 months for all patients. The 5-year estimated PFS rates of groups A, B and C were 61%, 38% and 49%, respectively. Both the OS and PFS of group A were higher than those of both group B and group C. On multivariate analysis, baseline dFLC > 50 mg/L was associated with worse survival, but induction with bortezomib was associated with better survival. CONCLUSION: Our study demonstrated that low disease burden AL patients who are eligible for ASCT may benefit from bortezomib-based induction therapy.

Challenges in the management of patients with systemic light chain (AL) amyloidosis during the COVID-19 pandemic.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated coronavirus disease 2019 (COVID-19) is primarily manifested as a respiratory tract infection, but may affect and cause complications in multiple organ systems (cardiovascular, gastrointestinal, kidneys, haematopoietic and immune systems), while no proven specific therapy exists. The challenges associated with COVID-19 are even greater for patients with light chain (AL) amyloidosis, a rare multisystemic disease affecting the heart, kidneys, liver, gastrointestinal and nervous system. Patients with AL amyloidosis may need to receive chemotherapy, which probably increases infection risk. Management of COVID-19 may be particularly challenging in patients with AL amyloidosis, who often present with cardiac dysfunction, nephrotic syndrome, neuropathy, low blood pressure and gastrointestinal symptoms. In addition, patients with AL amyloidosis may be more susceptible to toxicities of drugs used to manage COVID-19. Access to health care may be difficult or limited, diagnosis of AL amyloidosis may be delayed with detrimental consequences and treatment administration may need modification. Both patients and treating physicians need to adapt in a new reality.

A validated composite organ and hematologic response model for early assessment of treatment outcomes in light chain amyloidosis.

Newly diagnosed AL amyloidosis patients were evaluated to develop a model for early assessment of treatment benefit at 6 months, integrating both hematologic (HR) and organ response (OR) assessment (testing cohort, Mayo: n = 473; validation cohort, Pavia: n = 575). Multiple OR were assessed as follows: All OR (AOR): response in all organs, mixed OR (MOR): response in some organs, no OR (NOR)]. AOR rates at 6 months improved with deepening HR; complete response (CR; 38%, 35%), very good partial response (VGPR; 30%, 26%), and partial response (PR; 16%, 21%), respectively. A composite HR/OR (CHOR) model was developed using incremental scoring based on hazard ratios with scores of 0-3 for HR (0-CR, 1-VGPR, 2-PR, 3-no response) and 0-2 for OR (0-AOR, 1-MOR, 2-NOR). Patients could be divided into two distinct CHOR groups (scores 0-3 and 4-5), with median OS in group 1 and group 2: Not reached vs. 34 months, p < 0.001 [Mayo] and 87 vs. 23 months, p < 0.001 [Pavia]. In conclusion, we developed a model that can assess multiple organs concurrently, and integrate both HR and OR assessments to determine early clinical benefit with treatment, which may be used as a surrogate end-point in trials and to compare outcomes with different therapies.

Assessment of minimal residual disease using multiparametric flow cytometry in patients with AL amyloidosis.

Despite achieving a hematologic complete response after treatment, many patients with AL amyloidosis do not attain recovery of organ function and/or experience hematologic relapse. A persistent plasma cell clone producing amyloidogenic light chains at levels below the detection threshold of traditional serologic methods is hypothesized to impede organ response in some patients. Assessment of minimal residual disease (MRD) may therefore have clinical importance as a more stringent treatment response tool for patients in a hematologic complete response. We used 2-tube, 10-color combination multiparametric flow cytometry to assess for MRD at a minimum sensitivity of 1 in 105 nucleated cells. Of 65 patients in hematologic complete response, 36 (55%) were found to have a residual clonal plasma cell population in the bone marrow. Comparing the MRD-negative and MRD-positive groups, renal response was observed in 88% vs 64% (P = .06), cardiac response in 75% vs 59% (P = .45), and any organ response in 90% vs 75% (P = .20) of patients. Depth of organ response as measured by the percent decrease in 24-hour proteinuria and brain natriuretic peptide was 96% vs 91% (P = .16) and 55% vs 46% (P = .66), respectively. These data suggest a possible correlation between MRD negativity and higher probability of organ response after treatment in AL amyloidosis. Future prospective studies with a larger cohort are needed to determine the clinical relevance of these improvements. This trial was registered at www.clinicaltrials.gov as #NCT00898235.

Assessment of prognosis in immunoglobulin light chain amyloidosis patients with severe heart failure: a predictive value of right ventricular function.

Although the benefit of updated therapeutic regimens, including bortezomib, on the survival of immunoglobulin light chain (AL) amyloidosis patients with heart failure (HF) has been reported, predictors of mortality in the patients treated with the updated therapy remain unclear. We retrospectively enrolled AL amyloidosis patients who had severe HF at the time of diagnosis and received the updated therapy, including bortezomib (n = 19, 61 ± 6 years old, 68% male). Severe HF was defined as the presence of both NYHA functional class III or IV and BNP > 200 pg/ml or NT-pro-BNP > 900 pg/ml. One-year mortality rate during follow-up after commencement of the treatment was 37%. Left ventricular morphological parameters and indexes of left ventricular diastolic function on admission were similar in the non-survivors and survivors. However, non-survivors had higher incidences of atrial fibrillation and ventricular tachycardia, higher serum total bilirubin levels (1.34 ± 0.55 vs. 0.61 ± 0.29 mg/dl), higher right atrial volume index (RAVI 49.7 ± 29.9 vs. 27.3 ± 6.8 ml/m2), lower tricuspid annular peak velocities during systole (RVs' 8.0 ± 1.8 vs. 11.6 ± 3.7 cm/sec) and late diastole (RVa' 3.4 ± 0.9 vs. 11.4 ± 5.3 cm/sec), and larger inferior vena cava dimension (22.7 ± 6.4 vs. 16.3 ± 4.9 mm) than those in survivors. Kaplan-Meier curve analyses showed that larger RAVI and lower RVs' and RVa', but not left ventricular systolic/diastolic dysfunction, predicted higher mortality during 1-year follow-up. The present results suggest that the presence of right-sided heart abnormality on admission is associated with high 1-year mortality in AL amyloidosis patients with severe HF under the updated therapeutic regimens.

New developments in diagnosis, risk assessment and management in systemic amyloidosis.

Amyloidosis is a group of disorders characterized by a misfolded protein that deposits in organs and compromise their function. Clinician should have a high index of suspicion because in most cases, the clinical picture is non-specific. Typing of amyloid is of utmost importance and should be an integral part of accurately diagnosing a patient. AL amyloidosis is the most common systemic amyloidosis in the western world in which the misfolded proteins are immunoglobulin light chains secreted by clonal plasma cells. New data about prognostication of AL amyloidosis patients are accumulating. The treatment goal is to eradicate the amyloidogenic plasma cell clone, by using high dose melphalan and/or novel agents (proteasome inhibitors, immunomodulatory drugs, monoclonal antibodies against CD38). Early diagnosis is important for effectively treating the patient as late diagnosis hampers chances for organ recovery. ATTR amyloidosis is less recognized but is increasingly seen due to better recognition and improved diagnostic tools. New data about treatment options (patisiran, inotersen and tafamidis) have recently been published and are discussed.

Patient-reported outcomes in systemic AL amyloidosis with functional assessment of cancer therapy-general (FACT-G) and patient-reported outcomes measurement information system-global health (PROMIS-GH) in a real-world population.

We performed an observational study on health-related quality of life (HRQoL) in patients with AL amyloidosis diagnosed between 2012 and 2017 at our institution. A total of 81 patients were included, with a median age of 64 years. The mean FACT-G (Functional Assessment of Cancer Therapy-General) total score at baseline (≤2 months from diagnosis) was 74 (±15), compared to a normative score of 80 (±18) in the general U.S. population. Significant HRQoL deficit was noted only in the functional well-being (FWB) domain of FACT-G. Using PROMIS-GH (Patient-Reported Outcomes Measurement Information System-Global Health) at baseline (n = 18), a greater deficit was noted in the global physical health (GPH) compared to global mental health (GMH) domain. FACT-FWB and PROMIS-GPH domain scores were able to significantly discriminate between revised Mayo stages. Development and validation of an amyloid-specific PRO instrument incorporating specific domains of interest is urgently needed to pursue patient-centered drug development.

Left ventricular assessment in patients with systemic light chain amyloidosis: a 3-dimensional speckle tracking transthoracic echocardiographic study.

Cardiac involvement in systemic light chain (AL) amyloidosis carries a poor prognosis mainly through involvement of the left ventricular (LV) myocardium. Despite its limitations, two-dimensional transthoracic echocardiography (2D-TTE) remains the main tool used for the assessment of LV systolic function in AL patients. We hypothesize that 3D-TTE coupled with speckle tracking imaging allows earlier detection of LV systolic dysfunction than 2D-TTE in AL amyloidosis. We prospectively studied 71 subjects including 58 patients with confirmed AL amyloidosis (mean age 66 ± 10 years, 60% male) and 21 healthy control (mean age 64 ± 7 years, 48% male) from 2011 to 2014 at the University Hospital of Limoges. The AL patients were divided into three groups according to Mayo Clinic (MC) staging and all subjects underwent 2D-TTE and 3D-TTE at the same setting. Using 2D-TTE, there was no significant difference in LV ejection fraction (EF) between the groups [LVEF = 63 ± 7% (control), 59 ± 6% (MC stage I), 60 ± 8% (MC stage II) and 57 ± 14% (MC stage III) (p = 0.24)]. In contrast, 3D-TTE demonstrated significantly worse LV systolic function in stage II and III patients using 3D-LVEF [MC II and III 45 ± 8% and 39 ± 12% vs. control 53 ± 8% (p < 0.0001)], global longitudinal strain (GLS) [MC II and III - 11 ± 4% and - 8 ± 3% vs. control - 15 ± 3% (p < 0.0001)] and global radial strain (GRS) [MC II and III 14 ± 9% and 10 ± 8% vs. control 25 ± 10% (p < 0.0001)]. Furthermore, MC III patients had significantly worse global circumferential strain and area tracking [- 17 ± 6% and - 25 ± 8% vs. - 24 ± 7% and - 36 ± 7% for control (p < 0.0001)]. Additionally, MC I had significantly better 3D GLS, GRS and global strain (- 15 ± 3%, 25 ± 10% and 28 ± 12%) than MC II (- 11 ± 4%, 14 ± 9% and 16 ± 10%) and MC III patients (- 8 ± 3%, 10 ± 8% and 12 ± 8%), respectively. Despite an apparently preserved LVEF by 2D-TTE, AL patients in MC stage II and III demonstrate evidence of LV systolic dysfunction by 3D imaging using LVEF and strain analysis. Worse LV involvement by AL amyloidosis was associated with more impaired 3D-TTE LV systolic parameters.

Flow cytometry for fast screening and automated risk assessment in systemic light-chain amyloidosis.

Early diagnosis and risk stratification are key to improve outcomes in light-chain (AL) amyloidosis. Here we used multidimensional-flow-cytometry (MFC) to characterize bone marrow (BM) plasma cells (PCs) from a series of 166 patients including newly-diagnosed AL amyloidosis (N = 94), MGUS (N = 20) and multiple myeloma (MM, N = 52) vs. healthy adults (N = 30). MFC detected clonality in virtually all AL amyloidosis (99%) patients. Furthermore, we developed an automated risk-stratification system based on BMPCs features, with independent prognostic impact on progression-free and overall survival of AL amyloidosis patients (hazard ratio: ≥ 2.9;P ≤ .03). Simultaneous assessment of the clonal PCs immunophenotypic protein expression profile and the BM cellular composition, mapped AL amyloidosis in the crossroad between MGUS and MM; however, lack of homogenously-positive CD56 expression, reduction of B-cell precursors and a predominantly-clonal PC compartment in the absence of an MM-like tumor PC expansion, emerged as hallmarks of AL amyloidosis (ROC-AUC = 0.74;P < .001), and might potentially be used as biomarkers for the identification of MGUS and MM patients, who are candidates for monitoring pre-symptomatic organ damage related to AL amyloidosis. Altogether, this study addressed the need for consensus on how to use flow cytometry in AL amyloidosis, and proposes a standardized MFC-based automated risk classification ready for implementation in clinical practice.