Thrombotic and bleeding complications in patients with AL amyloidosis.

Haemostatic abnormalities and deregulated coagulation are common complications in AL amyloidosis. The relevant risks of thromboembolic and haemorrhagic events have not been thoroughly evaluated. To describe clinically significant thrombotic/haemorrhagic events in 450 consecutive patients with AL amyloidosis. Venous thromboembolic events (VTEs) were reported in 6% and arterial embolic events (AEEs) in 5% of patients, respectively, during a 55-month median follow-up. Lower albumin, lower eGFR, higher BM infiltration, soft tissue involvement, IMiD-based therapy and prior thrombosis were associated with VTE risk. Prior thrombosis was the only independent prognostic variable (HR 9.3, p = 0.001). Coronary arterial disease, prior AEE, 24-h proteinuria and higher platelet counts were associated with AEE risk. Significant bleeding events were reported in 9%, and associated mortality was 19%. Liver involvement, higher serum creatinine and higher baseline VWF:Ag levels were linked to bleeding risk. Using competing risk analysis, the cumulative probability of thrombosis/bleeding was higher during the first year following diagnosis, but a stable lower risk for both events remained for the duration of follow-up. In AL amyloidosis patients, the risk of thrombotic/arterial embolic events is significant, but the bleeding risk is also high. A multiparametric assessment is required to initiate anti-thrombotic or anti-platelet therapy appropriately.

Pulmonary function tests reveal unrecognised lung dysfunction and have independent prognostic significance in patients with systemic AL amyloidosis.

BACKGROUND: Lung involvement in AL amyloidosis is not very common, but post-mortem data and retrospective studies suggest it is likely underrecognized. AIM: To perform a comprehensive evaluation of lung function with pulmonary function tests (PFTs) in patients with newly diagnosed AL amyloidosis. METHODS: A prospective, non-interventional study of 139 consecutive patients with newly diagnosed AL amyloidosis. RESULTS: PFTs indicated normal breathing physiology in 68% of patients, obstructive in 9% and restrictive in 23%; the latter was associated with worse survival (28.6 vs 76 months for obstructive/normal physiology, p = 0.002) and remained significant after adjustment for Mayo stage and abnormal chest-CT. Forced vital capacity <80% of predicted value, forced expiratory volume <80% of predicted value, and carbon monoxide diffusion capacity <70% were independently associated with poorer survival. Respiratory muscle strength (as assessed by maximal expiratory (Pe) and inspiratory (Pi) pressure) was affected in most patients (64% had Pi < 55% and 57% had Pe < 70% of predicted values). Pe% was an independent prognostic factor for survival (HR: 0.984 per 1% unit increase, p = 0.007). CONCLUSIONS: Pulmonary dysfunction, as assessed with PFTs, is common and underrecognized in patients with systemic AL amyloidosis, with significant prognostic and potentially therapeutic implications, independent of the degree of cardiac dysfunction or chest-CT findings.

Determining patterns of vascular function and structure in wild-type transthyretin cardiac amyloidosis. A comparative study.

BACKGROUND: The impact of wild-type transthyretin-related cardiac amyloidosis (ATTRwt) on functional and structural peripheral vascular measures is unknown. In the present study, we explored patterns of vascular dysfunction in patients with ATTRwt in comparison to diseases with similar cardiac phenotype. METHODS: Treatment-naïve patients with ATTRwt (n = 32) were compared to: 1. Age-and sex-matched reference population without amyloidosis (n = 32), 2. Age-and sex-matched patients with systemic AL amyloidosis (n = 32), and 3. patients with cardiac AL amyloidosis (AL-HF, n = 23) or elderly patients with heart failure with preserved ejection fraction (HFpEF) (n = 16). All subjects underwent peripheral vascular assessment using carotid artery ultrasonography, brachial artery flow-mediated dilation (FMD), measurement of arterial stiffness and aortic hemodynamics including heart rate-adjusted time of return of reflected waves (Tr/HR). RESULTS: After adjustment for traditional cardiovascular risk factors and coronary artery disease (core model), peripheral and aortic blood pressures (BP) were lower in patients with ATTRwt (p < 0.05) whereas other vascular markers were preserved compared to the reference non-amyloidosis group. ATTRwt was independently associated with lower BP and longer Tr/HR compared to AL. Compared to AL-HF, FMD was lower in ATTRwt (p = 0.033). ATTRwt patients had lower BP and higher Tr/HR than HFpEF (p < 0.05). By ROC analysis, Tr/HR discriminated ATTRwt vs. AL-HF (sensitivity 93%, specificity 75%) and HFpEF (sensitivity 100%, specificity 94%) and lower FMD increased the likelihood for ATTRwt at low Tr/HR values. CONCLUSION: ATTRwt patients present a distinct peripheral vascular fingerprint which is different from AL-HF or HFpEF, consisting of lower peripheral and aortic BP, prolonged Tr/HR and FMD at reference-population range.

Consolidation with a short course of daratumumab in patients with AL amyloidosis or light chain deposition disease.

Daratumumab has major and rapid activity in AL amyloidosis with favourable toxicity. We used as a consolidation a short course of daratumumab in 25 patients with AL amyloidosis or light chain deposition disease (LCDD), who had not achieved a haematologic complete response (hemCR) after standard therapy with bortezomib, cyclophosphamide and dexamethasone (VCD). We evaluated minimal residual disease (MRD) and changes in the bone marrow (BM) microenvironment before and after consolidation using next generation flow cytometry (NGF). At the time of consolidation, 21 patients were in very good partial response (VGPR) and four in partial response (PR); all had detectable MRD. One month after consolidation completion, 8 patients (32%) achieved a hemCR, of whom 5 (20%) became also MRD negative. In the BM, we observed significant changes in B-cell precursors, naïve B-cells, T-cells, CD27+ NK & NKT cells, mast cells and erythroblasts. After a median follow-up of 25 months, none of the patients in hemCR has relapsed and all have achieved an organ response; a haematologic relapse occurred in 6/17 patients that did not achieve hemCR. In conclusion, consolidation with a short course of daratumumab can improve depth of response in patients with AL amyloidosis or LCDD and significantly affects BM environment.

Carfilzomib-induced endothelial dysfunction, recovery of proteasome activity, and prediction of cardiovascular complications: a prospective study.

Carfilzomib (CFZ) improves survival in relapsed/refractory multiple myeloma but is associated with cardiovascular adverse events (CVAEs). We prospectively investigated the effect of CFZ on endothelial function and associations with CVAEs. Forty-eight patients treated with Kd (CFZ 20/56 mg/m2 and dexamethasone) underwent serial endothelial function evaluation, using brachial artery flow-mediated dilatation (FMD) and 26S proteasome activity (PrA) measurement in PBMCs; patients were followed until disease progression or cycle 6 for a median of 10 months. FMD and PrA decreased acutely after the first dose (p < 0.01) and FMD decreased at cycles 3 and 6 compared to baseline (p ≤ 0.05). FMD changes were associated with CFZ-induced PrA changes (p < 0.05) and lower PrA recovery during first cycle was associated with more prominent FMD decrease (p = 0.034 for group interaction). During treatment, 25 patients developed Grade ≥3 CVAEs. Low baseline FMD (HR 2.57 lowest vs. higher tertiles, 95% CI 1.081-6.1) was an independent predictor of CVAEs. During treatment, an acute FMD decrease >40% at the end of first cycle was also independently associated with CVAEs (HR = 3.91, 95% CI 1.29-11.83). Kd treatment impairs endothelial function which is associated with PrA inhibition and recovery. Both pre- and posttreatment FMD predicted CFZ-related CVAEs supporting its role as a possible cardiovascular toxicity biomarker.

Next generation flow cytometry for MRD detection in patients with AL amyloidosis.

The treatment of AL amyloidosis aims to eradicate the plasma cell clone and eliminate toxic free light chain production. Only in a minority of patients the plasma cell clone is completely eradicated; residual light chain production may still exist while clonal relapse may occur. We used sensitive next-generation flow cytometry (NGF) to detect minimal residual disease (MRD) in AL amyloidosis patients at complete haematologic response. MRD evaluation was feasible in 51 of 52 (98%) tested patients and at a median sensitivity of 2.3 × 10-6 MRD was undetectable in 23 (45%). An organ response occurred in 86% of MRDneg vs 77% in MRDpos; renal response in 15/17(88%) of MRDneg vs in 14/16(87.5%) of MRDpos and cardiac response in 10/10(100%) of MRDneg vs 11/15(73%) of MRDpos patients. After a median follow-up of 24 months post MRD testing, no MRDneg patient had a haematologic relapse vs 6/28(21%) MRDpos (p = .029). Pooling haematologic and organ progressions, 9 (32%) MRDpos patients had disease progression vs only 1 (4%) MRDneg patient (p = .026). In conclusion, MRD detection using NGF has profound clinical implications, so that AL patients with undetectable MRD have a very high probability of organ response and a very low probability of haematologic relapse.

Daratumumab-based therapy for patients with monoclonal gammopathy of renal significance.

Treatment of the plasma cell clone in monoclonal gammopathy of renal significance (MGRS) is necessary in order to reduce toxic immunoglobulin load to the kidneys and salvage renal function. There are limited data on the use of daratumumab in patients with MGRS. We summarize our experience with the use of daratumumab-based therapy in 25 MGRS patients, 12 of whom were previously untreated. The median follow-up of the cohort is 14 months. The best overall haematologic response in evaluable patients was complete response (CR) in five (22%), very good partial response (VGPR) in five (22%) and partial response (PR) in seven (30%) patients for an overall response rate of 74%. Two of five patients in CR and two patients with initially detectable clones, but non-measurable immunoglobulins, had undetectable minimal residual disease (MRD) with next-generation flow cytometry (NGF) after therapy. Haematologic response rate for previously untreated patients was 83% vs. 69% for previously treated and for daratumumab combinations it was 91% vs. 64%, and with CR/VGPR 82% vs. 29%, compared to daratumumab monotherapy. At six months, 12/22 (55%) patients not on dialysis achieved a reduction of proteinuria >30%, of at least 0·5 g/24 h, without an estimated glomerular filtration rate (eGFR) reduction. The toxicity was mild and predictable. In conclusion, daratumumab-based therapy is a new option for patients with MGRS.

Timing and impact of a deep response in the outcome of patients with systemic light chain (AL) amyloidosis.

A rapid and deep haematologic response is fundamental in order to improve outcomes of patients with AL amyloidosis. We evaluated the impact of timing and depth of haematologic response at early time points (at 1 and 3 months from the start of therapy) in 227 consecutive previously untreated AL patients, who received bortezomib-based primary therapy. After 1 month of therapy, 30.5% had ≥VGPR, 28% PR and 36% no response (NR), with 11% having iFLC <20 mg/L and 15% dFLC <10 mg/L. Deep haematologic response at 1 month (either ≥VGPR or iFLC <20 mg/L or dFLC <10 mg/L), was associated with a high organ response rate. The survival of patients with ≥VGPR was significantly better than those with PR and NR at 1-month landmark (p < .001) but this benefit was mainly driven by those with iFLC <20 mg/L. The depth of haematologic response at 1 month was significant across all Mayo stages. At 3 months, 46% of the patients had not significantly improved the depth of their response but even patients that improved their response from an iFLC ≥20 mg/L at 1 month to iFLC <20 mg/L at 3 months still had inferior outcome to those with an early deep response. Thus, in patients with AL amyloidosis, a very rapid and deep response is crucial, especially for those at high risk, targeting very low FLC levels within the first month of therapy.

Carfilzomib-associated renal toxicity is common and unpredictable: a comprehensive analysis of 114 multiple myeloma patients.

Carfilzomib (CFZ) is a non-reversible proteasome inhibitor approved for the treatment of patients with relapsed and refractory myeloma (RRMM). Its use has been associated with cardiovascular toxicity but although recently a signal of clinically significant renal complications has also been identified, it is less extensively investigated. We analyzed data of 114 consecutive patients with RRMM who received CFZ-based regimens. Renal complications not related to MM progression were observed in 19 (17%) patients; thrombotic microangiopathy (TMA) was seen in 6 (5%) patients, albuminuria >1 gr/day in 7 patients (6%) and at least grade 3 acute kidney injury (AKI) which could not be otherwise explained in 6 patients (5%). A total of 15 patients discontinued CFZ and dosing was reinitiated at a lower level in one patient with AKI. Albuminuria was associated with focal segmental glomerulosclerosis in the renal biopsy (performed in a total of 6 patients). Renal complications during CFZ therapy are common, occur mostly early and are unpredictable. A potential effect of CFZ on the renal endothelium could be implicated in the pathogenesis of these complications and may also share common pathophysiology with cardiovascular effects of CFZ.

Involvement of small nerve fibres and autonomic nervous system in AL amyloidosis: comprehensive characteristics and clinical implications.

Peripheral nerve involvement in immunoglobulin light chain (AL) amyloidosis is common, characterised by severe progressive mixed neuropathy with autonomic dysfunction but there is limited data on the implications and the characteristics of small nerve fibres dysfunction (SNFD). The aim of our prospective study was to evaluate SNFD and its clinical implications in newly diagnosed AL patients. Twenty-three consecutive patients (10 male, mean age 61.78 years) and 21 age- and gender-matched healthy controls (8 male, mean age 61.28 years) underwent clinical evaluation and standard nerve conduction studies (NCS), baroreflex sensitivity (BRS) test, quantitative sensory testing (QST) and skin biopsy at the lower leg for measuring the density of the nerve fibres innervating the epidermis (IENFD). Axonal degeneration of the large nerve fibres was revealed in 15 out of 23 patients while SNFD was indicated by QST and skin biopsy in 56% and 61% of the patients respectively. BRS index significantly correlated with the IENFD and the QST results while low IENFD was associated with significantly poorer survival. Our study provides new insights and also an initial evaluation of new tools for assessment of the involvement of autonomic and small nerve fibres in AL amyloidosis. These findings also appear to have prognostic implications.

Impact of last lenalidomide dose, duration, and IMiD-free interval in patients with myeloma treated with pomalidomide/dexamethasone.

To gain insights into the characteristics of clinical resistance to lenalidomide, we evaluated the outcomes of 147 consecutive patients with multiple myeloma (MM) homogeneously treated with immunomodulatory imide drugs (IMiDs) pomalidomide and dexamethasone (Pd) for relapsed and/or refractory MM (median, 3 prior lines of treatment). We focused our analysis on the effect of the lenalidomide dose at which resistance was developed, the duration of lenalidomide exposure, and lenalidomide-free interval. On intent to treat, 33% of patients achieved ≥partial remission (PR) with Pd. When Pd was given immediately after lenalidomide, ≥PR was 32% (vs 37% after bortezomib). The response rates were similar for patients that received 5 to 15 mg vs 25 mg of lenalidomide (38.5% vs 30.5%, P = .329). Response rates were higher for patients that had received at least 12 months of lenalidomide (44% vs 27%) and for those with ≥18 months from last lenalidomide dose to pomalidomide dose (65% vs 23%). Median progression-free survival (PFS) and overall survival (OS) were 5 and 12.1 months, respectively, which was similar for patients who received lenalidomide, bortezomib or other regimens just before Pd and similar for patients who were receiving different doses of lenalidomide. IMiD-free interval ≥18 months was associated with longer PFS (10.3 vs 3.9 months, P = .003) and OS (27.1 vs 9.3, P = .008) as well as duration of last lenalidomide therapy ≥12 months (PFS: 7.8 vs 3.2, P = .023; OS: 16.5 vs 7.9, P = .005) even after adjustment for the number of prior therapies, duration of disease, and last lenalidomide dose.

Primary treatment of light-chain amyloidosis with bortezomib, lenalidomide, and dexamethasone.

Bortezomib and dexamethasone with cyclophosphamide (CyBorD) or melphalan (BMDex) are commonly used primary treatments for light-chain (AL) amyloidosis, but limited data exist on bortezomib with immunomodulatory drug combinations. We report our experience with primary therapy with a bortezomib, lenalidomide, and dexamethasone (VRD) "light" regimen in 34 consecutive patients with AL amyloidosis. The majority (79%) had cardiac involvement, 15% and 23% were Mayo stage 3A and 3B, respectively, and 54% had renal involvement. After the first VRD cycle, 71% of patients achieved a hematologic response (44% at least very good partial response [VGPR]). On intent to treat, 11 (32%) achieved a complete response (of whom 5 of 11 were minimal residual disease [MRD] negative at 10-5), 17 (50%) a VGPR, and 2 (7%) a partial response. The 12-month survival was 73%. Starting lenalidomide dose was 5 mg in 86% of patients. Hematologic toxicity was mild; nonhematologic toxicities included rash (grade 3/4 [16%]), infections (grade ≥3 [12%]), constipation (grade ≥3 [9%]), and peripheral neuropathy (grade 2 [20%]); 37.5% of patients required lenalidomide dose reduction, 27% discontinued lenalidomide, 38% required bortezomib dose reduction, and 12% discontinued bortezomib. We compared VRD to CyBorD in 68 patients matched for Mayo stage and baseline difference between involved minus uninvolved serum free light chain levels, and observed a trend for deeper response at 3 and 6 months with VRD. In conclusion, VRD can be an active regimen for newly diagnosed patients with AL amyloidosis able to induce very deep hematologic responses at the expense of increased toxicity.

Elevated vWF Antigen Serum Levels Are Associated With Poor Prognosis, and Decreased Circulating ADAMTS-13 Antigen Levels Are Associated With Increased IgM Levels and Features of WM but not Increased vWF Levels in Patients With Symptomatic WM.

BACKGROUND: Waldenström's macroglobulinemia (WM) is a rare malignancy characterized by bone marrow infiltration by lymphoplasmacytic cells and the presence of a monoclonal IgM paraprotein. The interactions of lymphoplasmacytic cells with other cells in their microenvironment, including mast cells and endothelial cells, support their survival and proliferation and can induce resistance to therapy. von Willebrand factor (vWF) plays a key role in primary hemostasis but is also a marker of endothelial "stimulation." High levels of vWF have been associated with an adverse prognosis in patients with symptomatic WM and might reflect the interactions between lymphoplasmacytic cells and other cells of their microenvironment. MATERIALS AND METHODS: Considering vWF and ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) as markers of endothelial dysfunction and activation, we evaluated the prognostic importance of vWF and ADAMTS-13 antigen levels in the serum of patients with previously untreated symptomatic WM to validate vWF as a possible prognostic marker for progression-free and overall survival. We also validated the measurement of vWF in the serum instead of citrated plasma and investigated the possible correlations of ADAMTS-13 antigen levels with disease characteristics. The analysis included 42 patients with symptomatic WM and 19 matched healthy controls. RESULTS: The serum levels of vWF antigen provided significant prognostic information, and patients with levels ≥ 200 IU/dL had a very poor prognosis compared with patients with lower levels. The ADAMTS-13 antigen levels were decreased in WM patients and correlated with the IgM levels, ß2-microglobulin, and extent of bone marrow infiltration. CONCLUSION: vWF levels measured in the serum could become an important prognostic marker in patients with WM and requires further investigation.

Efficacy of lenalidomide as salvage therapy for patients with AL amyloidosis.

We retrospectively evaluated 55 consecutive patients who received at least one dose of lenalidomide for relapsed/refractory AL amyloidosis. Their median age was 63 years; 72% had heart and 75% kidney involvement and 13% were on dialysis; while 20%, 46% and 34% had Mayo stage -1, -2 and -3 disease, respectively. Median time from start of primary therapy to lenalidomide was 15 months (range 2-100) and median number of prior therapies was 1 (range 1-4); 73% of the patients had prior bortezomib and 42% were bortezomib-refractory. On intent to treat, haematologic response rate was 51% (5.5% CRs, 20% VGPRs) and was 56% versus 40% for patients with and without prior bortezomib and 47% versus 62.5% for bortezomib refractory versus non-refractory patients (p = .351). Organ response was achieved by 16% of evaluable patients (22% renal, 7% liver and 3% cardiac); however, 10 (21%) patients progressed to dialysis. Median survival post lenalidomide was 25 months. Bortezomib-refractory patients had worse outcome (median survival of 10.5 versus 25 months for bortezomib-sensitive patients versus not reached for bortezomib-naive patients, p = .011). Median lenalidomide dose was 10 mg and no patient received the 25 mg dose; however, in 60% a dose reduction was required. Median duration of lenalidomide therapy was 7.2 months and 46% discontinued lenalidomide before completion of planned therapy, mainly due to toxicity (26%) or disease progression/no response (13%). We conclude that although lenalidomide is a major salvage option for patients with relapsed/refractory AL amyloidosis, its toxicity in patients with AL amyloidosis is significant and doses should be adjusted for optimal tolerability.