Recent guidelines for high-dose chemotherapy and autologous stem cell transplant for systemic AL amyloidosis: a practitioner's perspective

INTRODUCTION: High-dose melphalan followed by autologous stem cell transplant (ASCT) has been transformative in treating AL amyloidosis since the early nineties. Recently, the European Hematology Association (EHA) and International Society of Amyloidosis (ISA) have developed a combined guideline for the management of patients undergoing an ASCT for AL amyloidosis. AREAS COVERED: In this practitioner's perspective, we review the guideline, focusing on 6 major areas and offer practical advice for its application. We provide a perspective on the optimal use of ASCT and its potential application in the future. EXPERT OPINION: The EHA-ISA guideline comprehensively outlines the practicalities of performing an ASCT in AL amyloidosis. The critical aspect is careful patient selection. Vigilant fluid balance assessments are crucial as associated complications are common and dangerous. The role of ASCT is changing with improving hematological responses associated with novel agents. Evidence is limited for the use of ASCT in patients who achieve a complete hematological response (CR). Therefore, ASCT should be considered for those who only achieve a very good partial response (VGPR)/partial response (PR) and fulfil the strict selection criteria. Future research identifying the cohort who would benefit most from ASCT in the era of novel therapies is warranted

Guidelines for non-transplant chemotherapy for treatment of systemic AL amyloidosis: EHA-ISA working group

Background: This guideline has been developed jointly by the European Society of Haematology and International Society of Amyloidosis recommending non-transplant chemotherapy treatment for patients with AL amyloidosis. / Methods: A review of literature and grading of evidence as well as expert recommendations by the ESH and ISA guideline committees. / Results and Conclusions: The recommendations of this committee suggest that treatment follows the clinical presentation which determines treatment tolerance tempered by potential side effects to select and modify use of drugs in AL amyloidosis. All patients with AL amyloidosis should be considered for clinical trials where available. Daratumumab-VCD is recommended from most untreated patients (VCD or VMDex if daratumumab is unavailable). At relapse, the two guiding principles are the depth and duration of initial response, use of a class of agents not previously exposed as well as the limitation imposed by patients’ fitness/frailty and end organ damage. Targeted agents like venetoclax need urgent prospective evaluation. Future prospective trials should include advanced stage patients to allow for evidence-based treatment decisions. Therapies targeting amyloid fibrils or those reducing the proteotoxicity of amyloidogenic light chains/oligomers are urgently needed

Prognostic importance of the 6 min walk test in light chain (AL) amyloidosis

OBJECTIVES: In AL amyloidosis, organ response assessment is based on surrogates (eg, cardiac biomarkers). An objective functional test, such as the 6 min walk test (6MWT), capturing overall clinical improvement, is required. We aimed to evaluate the prognostic impact of the 6MWT at baseline and change following chemotherapy. METHODS: This study evaluated the outcomes of patients who enrolled in a prospective observational study at the UK National Amyloidosis Centre (2012-2017). Patients underwent comprehensive assessments inclusive of blood testing, echocardiogram and 6MWT at baseline and annually thereafter. RESULTS: In total, 799 patients were included within the study. Median baseline 6 min walk distance (6MWD) was 362 m (IQR: 231 m). 6MWD progressively decreased with worsening cardiac disease stage (458 m, 404 m, 331 m and 168 m for cardiac Mayo stages I, II, IIIa and IIIb, respectively (p<0.0001)). In patients with a baseline 6MWT of ≥350 m, the median overall survival was not reached (vs 30.0 (95% CI 23.2 to 36.8) months if <350 m and 5.0 (95% CI 2.8 to 7.2) months if unable to attempt 6MWT (p<0.0001). Following chemotherapy, only patients in a complete haematological response improved their 6MWD by 12 months (p=0.001). Improvement in 6MWD prolonged survival in patients with cardiac amyloidosis (p=0.005). CONCLUSION: The 6MWT is prognostic in AL amyloidosis. A baseline distance of ≥350 m independently predicts better survival. These data suggest that 6MWT has utility in AL amyloidosis for baseline prognosis and assessing response

The experience of hereditary apolipoprotein A-I amyloidosis at the UK National Amyloidosis Centre

INTRODUCTION: Hereditary apolipoprotein A-I (AApoAI) amyloidosis is a rare heterogeneous disease with variable age of onset and organ involvement. There are few series detailing the natural history and outcomes of solid organ transplantation across a range of causative APOA1 gene mutations. METHODS: We identified all patients with AApoAI amyloidosis who presented to the National Amyloidosis Centre (NAC) between 1986 and 2019. RESULTS: In total, 57 patients with 14 different APOA1 mutations were identified including 18 patients who underwent renal transplantation (5 combined liver-kidney (LKT) and 2 combined heart-kidney (HKT) transplants). Median age of presentation was 43 years and median time from presentation to referral was 3 (0-31 years). Involvement of the kidneys, liver and heart by amyloid was detected in 81%, 67% and 28% of patients, respectively. Renal amyloidosis was universal in association with the most commonly identified variant (Gly26Arg, n = 28). Across all variants, patients with renal amyloidosis had a median creatinine of 159 µmol/L and median urinary protein of 0.3 g/24 h at the time of diagnosis of AApoAI amyloidosis and median time from diagnosis to end-stage renal disease was 15.0 (95% CI: 10.0-20.0) years. Post-renal transplantation, median allograft survival was 22.0 (13.0-31.0) years. There was one early death following transplantation (infection-related at 2 months post-renal transplant) and no episodes of early rejection leading to graft failure. Liver transplantation led to regression of amyloid in all four cases in whom serial 123I-SAP scintigraphy was performed. CONCLUSIONS: AApoAI amyloidosis is a slowly progressive disease that is challenging to diagnose. The outcomes of transplantation are encouraging and graft survival is excellent

Prognostic Value of a 6-Minute Walk Test in Patients With Transthyretin Cardiac Amyloidosis

Background The 6-minute walk test (6MWT) represents a comprehensive functional assessment that is commonly used in patients with heart failure; however, data are lacking in patients with transthyretin cardiac amyloidosis (ATTR-CA). Objectives This study aimed to assess the prognostic importance of the 6MWT in patients with ATTR-CA.Methods A retrospective analysis of patients diagnosed with ATTR-CA at the National Amyloidosis Centre who underwent a baseline 6MWT between 2011 and 2023 identified 2,141 patients, of whom 1,118 had follow-up at 1 year.Results The median baseline 6MWT distance was 347 m (Q1-Q3: 250-428 m) and analysis by quartiles demonstrated an increased death rate with each distance reduction (deaths per 100 person-years: 6.3 vs 9.2 vs 13.6 vs 19.0; log-rank P &lt; 0.001). A 6MWT distance of 35 m) and relative worsening (reduction of &gt;5%) of 6MWT at 1 year was associated with an increased risk of mortality (HR: 1.80; 95% CI: 1.51-2.15; P &lt; 0.001 and HR: 1.89; 95% CI: 1.59-2.24; P &lt; 0.001, respectively), which was similar across the aforementioned subgroups. When combined with established measures of disease progression (N-terminal pro–B-type natriuretic peptide progression and outpatient diuretic intensification), each incremental increase in progression markers was associated with an increased death rate (deaths per 100 person-years: 7.6 vs 13.9 vs 22.4 vs 32.9; log-rank P &lt; 0.001). Conclusions The baseline 6MWT distance can refine risk stratification beyond traditional prognosticators. A worsening 6MWT distance can stratify disease progression and, when combined with established markers, identifies patients at the highest risk of mortality

Expansion of the National Amyloidosis Centre staging system to detect early mortality in transthyretin cardiac amyloidosis

Aims: Transthyretin cardiac amyloidosis (ATTR-CA) is stratified into prognostic categories using the National Amyloidosis Centre (NAC) staging system. The aims of this study were to further expand the existing NAC staging system to incorporate an additional disease stage that would identify patients at high risk of early mortality. Methods and results: The traditional NAC staging system (stage 1: N-terminal pro-B-type natriuretic peptide [NT-proBNP] ≤3000 ng/L and estimated glomerular filtration rate [eGFR] ≥45 ml/min; stage 3: NT-proBNP &gt;3000 ng/L and eGFR &lt;45 ml/min; stage 2: remainder) was expanded by the introduction of a new stage 4 (defined as NT-proBNP ≥10 000 ng/L irrespective of eGFR) and studied in 2042 patients. The optimal NT-proBNP cut-point was established using time-dependent receiver operating characteristic curves in the subgroup of patients with NAC stage 3 disease. Mortality at 1 year according to NAC stage was 2.3% (n = 20/886) for stage 1, 8.8% (n = 62/706) for stage 2, 10.4% (n = 28/270) for stage 3, and 30.6% (n = 55/180) for stage 4 (log-rank p &lt; 0.001). After adjustment for age, mortality hazard for stage 4 was &gt;15-fold higher than that of stage 1 (hazard ratio [HR] 15.5; 95% confidence interval [CI] 9.3-26.1) and &gt;3-fold higher than that of stage 3 (HR 3.4; 95% CI 2.2-5.4). The increased risk of early mortality was consistent across the different genotypes and subclasses of patients based on the severity of heart failure symptoms and echocardiographic parameters. Conclusions: The proposed modification of the NAC staging system identifies patients with ATTR-CA at a high risk of early mortality, who may benefit from a more intensive treatment strategy, and who are most likely to experience an event early in the course of a clinical trial

Albuminuria in transthyretin cardiac amyloidosis: Prevalence, progression and prognostic importance

Aims: Transthyretin cardiac amyloidosis (ATTR-CA) is an infiltrative cardiomyopathy that commonly presents with concomitant chronic kidney disease. Albuminuria is common in heart failure and associated with worse outcomes, but its prevalence and relationship to outcome in ATTR-CA remains unclear.Methods and results: A total of 1181 patients with ATTR-CA were studied (mean age 78.1 +/- 7.9 years; 1022 [86.5%] male; median estimated glomerular filtration rate 59 ml/min/1.73m(2) [interquartile range: 47-74]). Albuminuria was present in 563 (47.7%) patients (499 [88.6%] with microalbuminuria and 64 [11.4%] with macroalbuminuria). Patients with albuminuria had a more severe cardiac phenotype evidenced by higher serum cardiac biomarkers (median N-terminal pro-B-type natriuretic peptide [NT-proBNP]: 4027 ng/L [2173-6889] vs. 1851 ng/L [997-3209], p < 0.001; median troponin T: 69 ng/L [46-101] vs. 48 ng/L [34-68], p < 0.001) and worse echocardiographic indices of systolic (longitudinal strain: -10.0 +/- 3.6% vs. -11.6 +/- 3.8%, p < 0.001) and diastolic function (E/e': 17.5 +/- 6.4 vs. 16.4 +/- 6.7, p < 0.001) than those with a normal urinary albumin to creatinine ratio (UACR). Microalbuminuria and macroalbuminuria were independently associated with mortality in the overall population (hazard ratio [HR] 1.47, 95% confidence interval [CI] 1.13-1.92, p = 0.005 and HR 1.87, 95% CI 1.15-3.05, p = 0.012, respectively). In a subgroup of patients (n = 349) without concomitant hypertension, diabetes mellitus or chronic kidney disease, albuminuria was also associated with mortality (HR 2.98, 95% CI 1.72-5.17, p < 0.001). At 12 months, 330 patients had a repeat UACR measurement; those in whom UACR increased by 30% or more (n = 148, 44.8%) had an increased risk of mortality (HR 1.84, 95% CI 1.06-3.19, p = 0.030).Conclusions: Albuminuria is common in patients with ATTR-CA, and more prevalent in those with a more severe cardiac phenotype. Albuminuria at diagnosis and a significant increase in UACR during follow-up are associated with mortality

Cardiac biomarkers are prognostic in systemic light chain amyloidosis with no cardiac involvement by standard criteria

Patients with systemic immunoglobulin light chain amyloidosis (AL) with no evidence of cardiac involvement by consensus criteria have excellent survival, but 20% will die within 5 years of diagnosis and prognostic factors remain poorly characterised. We report the outcomes of 378 prospectively followed Mayo stage I patients (N-terminal pro b-type natriuretic peptide 10 ng/L and cardiac involvement by magnetic resonance imaging were predictive for survival; on multivariate analysis only N-terminal pro b-type natriuretic peptide >152 ng/L (P152 ng/L were alive. In conclusion, N-terminal pro b-type natriuretic peptide is prognostic for survival in patients with no cardiac involvement by consensus criteria and cardiac involvement is detected by magnetic resonance imaging in such cases. This suggests that N-terminal pro b-type natriuretic peptide thresholds for cardiac involvement in AL may need to be redefined