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.

Belantamab mafodotin, lenalidomide and dexamethasone in transplant-ineligible patients with newly diagnosed multiple myeloma: Part 1 results of a phase I/II study.

Preclinical and clinical data demonstrate synergy between belantamab mafodotin (belamaf) and immunomodulatory drugs with limited overlapping toxicities. We investigated the safety and efficacy of belamaf with lenalidomide 25mg on days 1-21 every 28 days and dexamethasone 40mg weekly (belamaf-Rd) in transplant ineligible patients with newly diagnosed multiple myeloma. 36 patients (median age 72.5 years) were randomized to receive belamaf at three different doses (2.5/1.9/1.4 mg/kg) every 8 weeks (q8w). Dosing schedule was extended to every 12 weeks (q12w) to account for ocular toxicity. Most common ≥ Grade (Gr) 3 adverse events were fatigue (n=21, 58.3%), rash (n=6, 16.7%), diarrhea (n=8, 22.2%) and COVID-19 (n=5, 13.9%). Gr 3-4 ocular adverse events (OAEs), comprising of visual acuity decline from baseline and/or keratopathy, were reported in 39/216(18.1%)/ 33/244(13.5%)/ 26/207(12.6%) ophthalmological assessments in cohorts 2.5/1.9/1.4 mg/kg. Importantly, Gr 3-4 keratopathy was identified in 9/216 (4.2%)/ 1/244(0.4%)/ 1/207(0.5%) assessments. Most patients (32/36, 88.9%) were treated in the extended q12w schedule, where dose holds due to OAEs were 40, 33 and 16 in cohorts 2.5/1.9/1.4. Overall, ≥VGPR and ≥CR rates were 83.3% and 52.8%, without significant differences among cohorts. Over a median follow-up of 20.3 months no disease progression was reported; 6 patients discontinued treatment due to infection-related death (n=4 COVID-19, n=2 pneumonia) and 1 patient withdrew consent. Based on toxicity/efficacy balance, the recommended phase 2 dose was 1.9 mg/kg q8w, extended to q12w for toxicity. Belamaf-Rd, with the extended schedule for belamaf, has shown important clinical activity and a significant improvement of OAEs with minimal impact on vision-related functioning in an elderly, non-transplant eligible population.

Outcomes of patients with light chain (AL) amyloidosis after failure of daratumumab-based therapy.

As daratumumab use in AL amyloidosis increases, more patients will either relapse after or become refractory to daratumumab. We present the outcome of 33 patients with AL who failed on daratumumab (due to haematological relapse in 21 [64%] patients and inadequate haematological response in 12 [36%]) and received further treatment. Overall response rate in the post-daratumumab failure treatment was 55% (CR/VGPR: 14 [42%] and PR: 3 [9%] patients). Patients retreated with daratumumab and patients harbouring +1q21 had lower rates of response. Treatment of patients with AL who fail daratumumab therapy is feasible when non-cross-resistant drugs or other targeted therapies are available.

Outcomes for patients with systemic light chain amyloidosis and Mayo stage 3B disease.

Patients with cardiac light chain amyloidosis and Mayo stage 3b disease define a high-risk population with very poor prognosis. Here, we report treatment outcomes of 80 consecutive patients with newly diagnosed AL and Mayo 3b who received novel regimens. Early mortality (<1 month) rate was 12.5%. On intention-to-treat, overall hematologic response rate was 40%, with complete response (CR)/very good partial response (VGPR) in 25% and partial response (PR) in 15%. At 1- and 3- month landmark analysis CR or VGPR/PR rates were 25%/23.5% and 34%/25.5%, respectively. Among patients that were treated with daratumumab-based therapies, 52.6% and 85.7% achieved at least VGPR within one 1 and 3 months, respectively. Three-month cardiac response rate was 11.3% and 6-month was 18.8%. At least hemVGPR at 3 months was associated with cardiac response at 6 months (p = 0.034). Median overall survival (OS) was 6.3 months. At 1-month landmark at least hemPR was associated with better median OS (24.1 vs. 4.9 months, p = 0.017) and at 3-month landmark, at least hemVGPR was associated with a median OS of 40.7 versus 17 months for hemPR and 7.4 months for those without hematologic response (p = 0.028). Cardiac response at 3 months was associated with longer median OS (59.7 vs. 10.9 months, p = 0.044). Factors associated with poorer survival were κ-light chain amyloidosis (median OS 2.9 vs. 7.4 months, p = 0.028), peripheral nerve involvement (3.4 vs. 10.45 months, p = 0.024), systolic blood pressure <90 mmHg (2 vs. 8 months, p = 0.002), baseline LVEF <55% (median OS 3.4 vs. 32 months, p = 0.29) and New York Heart Association (NYHA) class (2.7 months for NYHA 3B-4 vs. 8 months for NYHA 2-3A, p = 0.02). Twenty-one patients (26.3%) received salvage therapy and ORR was 57.1%. Median OS for patients who received second line therapy was 24 months. In conclusion, patients with Mayo 3b disease benefit from early hematologic response but cardiac response rates remain low.

Prognostic impact of translocation t(11;14) and of other cytogenetic abnormalities in patients with AL amyloidosis in the era of contemporary therapies.

OBJECTIVES: Translocation t(11;14) is the most common cytogenetic abnormality in patients with systemic AL amyloidosis with prognostic and therapeutic relevance, which has not been clearly defined in the most recent therapeutic era. METHODS: We assessed its prognostic role in 146 newly-diagnosed patients who received novel agent-based treatment combinations. Event-free survival (EFS), a composite endpoint defined by hematological progression, start of a new treatment-line or death, and overall survival (OS) were the primary endpoints. RESULTS: Half of the patients had at least one FISH abnormality; 40% had t(11;14) which was inversely associated with other cytogenetic abnormalities. At 1, 3, and 6-month landmarks, hematologic response rates were numerically but not statistically higher in the non-t(11;14) group. Patients with t(11;14) were more frequently switched to second-line treatment within 12 months (p = .015). At median follow-up of 31.4 months, t(11;14) was associated with shorter EFS [17.1 (95% CI 3.2-10.6) vs. 27.2 months (95% CI 13.8-40.6), p = .021] and retained its prognostic significance in the multivariate model (HR:1.66, p = .029). The effect on OS was neutral, possibly due to the use of effective salvage therapies. CONCLUSIONS: Our data support the use of targeted therapies for patients with t(11;14) to avoid delays in the achievement of deep hematologic responses.

Real-World Effectiveness and Safety of Belantamab Mafodotin Monotherapy in Triple-Class Refractory Multiple Myeloma.

B-cell maturation antigen (BCMA) is a promising therapeutic target for multiple myeloma (MM). The aim of this study was to assess the effectiveness and tolerability of monotherapy with the conjugated anti-BCMA monoclonal antibody belantamab mafodotin in triple-class refractory patients with MM in real-world practice. Patients refractory to at least one proteasome inhibitor, one immunomodulatory drug, and one anti-CD38 monoclonal antibody received belantamab mafodotin at 2.5 mg/kg intravenously every 3 weeks. Overall, 27 patients with a median age of 65 years (range 41-81) were included. Of these, 52% were male and the median number of prior lines of treatment was 5 (4-10). The overall response rate (partial response or better) was 52%, whereas the disease control rate (stable disease or better) was 70%. The median progression-free survival (PFS) was 2 months (95%CI: 0-7), whereas the median PFS among the responders was 12 months (95%CI: 6-18). Regarding the toxicity profile, the most common toxicity was eye toxicity, in 44% of the patients. Keratopathy grade 2-3 was reported in 33.3% of the patients. In conclusion, belantamab mafodotin showed a safety and efficacy profile consistent with the results of the registrational study. Importantly, heavily pretreated patients who responded to treatment derived a substantial survival benefit.

Myeloma patients with COVID-19 have superior antibody responses compared to patients fully vaccinated with the BNT162b2 vaccine.

Patients with multiple myeloma (MM) have a suboptimal antibody response following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and lower seroconversion rates following coronavirus disease 2019 (COVID-19) compared with healthy individuals. In this context, we evaluated the development of neutralising antibodies (NAbs) against SARS-CoV-2 in non-vaccinated patients with MM and COVID-19 compared with patients after vaccination with two doses of the BNT162b2 vaccine. Serum was collected either four weeks post confirmed diagnosis or four weeks post a second dose of BNT162b2. NAbs were measured with a Food and Drug Administration-approved enzyme-linked immunosorbent assay methodology. Thirty-five patients with COVID-19 and MM along with 35 matched patients were included. The two groups did not differ in age, sex, body mass index, prior lines of therapy, disease status, lymphocyte count, immunoglobulin levels and comorbidities. Patients with MM and COVID-19 showed a superior humoral response compared with vaccinated patients with MM. The median (interquartile range) NAb titre was 87·6% (71·6-94%) and 58·7% (21·4-91·8%) for COVID-19-positive and vaccinated patients, respectively (P = 0·01).Importantly, there was no difference in NAb production between COVID-19-positive and vaccinated patients who did not receive any treatment (median NAb 85·1% vs 91·7%, P = 0·14). In conclusion, our data indicate that vaccinated patients with MM on treatment without prior COVID-19 should be considered for booster vaccine doses.

Chromosome 1q21 aberrations identify ultra high-risk myeloma with prognostic and clinical implications.

Numerical abnormalities of chromosome 1q (+1q21) are common in patients with newly diagnosed multiple myeloma (MM) but their prognostic impact remains a matter of debate. In addition, the impact of the number of copies of 1q21 is not known. We analyzed 912 consecutive patients with symptomatic MM to evaluate the prognostic implications of +1q21 and of their copy number variations, as assessed by FISH. At the time of initial diagnosis, 249 (27.3%) patients had +1q21, of which 150 (16.4%) had 3 copies and 99 (10.9%) had 4 or more copies. Presence of +1q21 was associated with advanced ISS stage (p = .003), concurrent presence of other cytogenetics aberrations and advanced R-ISS stage (p < .001). Patients with +1q21 had inferior PFS (median 34 vs. 20 months, p < .001) and OS (median 75 vs. 44 months, p < .001) but the copy number of 1q21 had no additional prognostic impact. In multivariate analysis, adjusting for R-ISS, age, treatment and HDM, +1q21 remained an independent prognostic factor both for PFS (p < .001) and OS (p = .008). The detrimental prognostic effect of +1q21 was more profound in R-ISS-3 patients, identifying a subgroup with OS of just 16 months (vs. 46 for R-ISS-3 without +1q21, p < .001). We further validated our findings in an independent cohort of 272 patients. In conclusion, the presence of +1q21 is associated with more advanced disease, inferior PFS, and OS but especially patients with R-ISS-3 disease and +1q21 have a very poor outcome comprising an ultra-high-risk group.

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.

Biomarkers in AL Amyloidosis.

Systemic AL amyloidosis is a rare complex hematological disorder caused by clonal plasma cells which produce amyloidogenic immunoglobulins. Outcome and prognosis is the combinatory result of the extent and pattern of organ involvement secondary to amyloid fibril deposition and the biology and burden of the underlying plasma cell clone. Prognosis, as assessed by overall survival, and early outcomes is determined by degree of cardiac dysfunction and current staging systems are based on biomarkers that reflect the degree of cardiac damage. The risk of progression to end-stage renal disease requiring dialysis is assessed by renal staging systems. Longer-term survival and response to treatment is affected by markers of the underlying plasma cell clone; the genetic background of the clonal disease as evaluated by interphase fluorescence in situ hybridization in particular has predictive value and may guide treatment selection. Free light chain assessment forms the basis of hematological response criteria and minimal residual disease as assessed by sensitive methods is gradually being incorporated into clinical practice. However, sensitive biomarkers that could aid in the early diagnosis and that could reflect all aspects of organ damage and disease biology are needed and efforts to identify them are continuous.

Solid Organ Transplantation in Amyloidosis.

Amyloidosis comprises a diverse group of diseases characterized by misfolding of precursor proteins which eventually form amyloid aggregates and preceding intermediaries, which are deposited in target tissues causing progressive organ damage. In all forms of amyloidosis, vital organs may fail; depending on the specific amyloidosis type, this may occur rapidly or progress slowly. Beyond therapies to reduce the precursor protein (chemotherapy for light chain [AL] amyloidosis, anti-inflammatory therapy in serum A amyloid-osis [AA], and antisense RNA therapy in transthyretin amyloidosis [ATTR]), organ transplantation may also be a means to reduce amyloidogenic protein, e.g., in types of amyloid-osis in which the variant precursor is produced by the liver. Heart transplantation is a life-saving approach to the treatment of patients with advanced cardiac amyloidosis; however, amyloidosis may still be considered a contraindication to the procedure despite data supporting improved outcomes, similar to patients with other indications. Kidney transplantation is associated with particularly favorable outcomes in patients with amyloidosis, especially if the precursor protein has been eliminated. Overall, outcomes of solid organ transplantation are improving, but more data are needed to refine the selection criteria and the timing for organ transplantation, which should be performed in highly experienced centers involving multidisciplinary teams with close patient follow-up to detect amyloid recurrence.

Left ventricular myocardial work improves in response to treatment and is associated with survival among patients with light chain cardiac amyloidosis.

AIMS: Complete haematologic response to treatment for light chain cardiac amyloidosis (AL-CA) may lead to improvement of myocardial function and better outcomes. We sought to evaluate the effect of response to treatment for AL-CA on echocardiographic indices of myocardial deformation and work and their prognostic significance. METHODS AND RESULTS: Sixty-one patients treated for AL were enrolled and underwent echocardiographic assessment at baseline and at 1 year. Patients were stratified according to haematologic response as complete or not complete responders. A significant reduction in median N-terminal pro-brain natriuretic peptide (NT-proBNP) (2771-1486 pg/mL; P < 0.001) and posterior wall thickness (13-12 mm; P = 0.002) and an increase in global work index (GWI) (1115-1356 mmHg%; P = 0.018) was observed at 1 year. Patients with complete response (CR) had a more pronounced decrease in intraventricular septum thickness (14.2-12.0 mm; P = 0.006), improved global longitudinal strain (GLS) (-11.6 to -13.1%; P for interaction = 0.045), increased global constructive work (1245-1436 mmHg%; P = 0.008), and GWI (926-1250 mmHg%, P = 0.002) compared with non-CR. Furthermore, deltaGLS (ρspearman = 0.35; P < 0.001) and deltaGWI (ρspearman = -0.32; P = 0.02) correlated with delta NT-proBNP. Importantly, patients with GLS and GWI response had a better prognosis (log-rank P = 0.048 and log-rank P = 0.007, respectively). After adjustment for Mayo stage, gender, and response status, deltaGLS [hazard ratio (HR) = 1.404, P = 0.046 per 1% increase] and deltaGWI (HR = 0.996, P = 0.042 per 1mmHg% increase) were independent predictors of survival. CONCLUSION: Complete haematologic response to treatment is associated with improved left ventricular myocardial work indices, and their change is associated with improved survival in AL-CA.

Characteristics and Outcomes of Patients With Relapsed/Refractory Multiple Myeloma After Exposure to Lenalidomide in First Line of Therapy: A Single Center Database Review in Greece.

BACKGROUND: The increasing use of lenalidomide (Len) in first-line (1L) therapy of multiple myeloma (MM) has led to a significant proportion of patients becoming Len-refractory following 1L treatment. However, there are limited real-world data on treatment strategies and outcomes of patients who become Len-refractory following 1L therapy. PATIENTS AND METHODS: This real-world retrospective cohort study analyzed Len-refractory and non-Len-refractory patients who received 1L Len and initiated second-line (2L) therapy at a Greek MM center. The Len-exposed cohort (n = 249) included 55.4% Len-refractory patients after 1L. RESULTS: Compared to non-Len-refractory patients, Len-refractory patients more frequently had high-risk cytogenetics and Revised-International Staging System-3 disease stage at diagnosis, and had shorter progression-free survival (PFS) following 1L therapy. Len-refractory versus non-Len-refractory patients more frequently received triplets (59% vs. 40%), anti-CD38 agents (20% vs. 9%) and pomalidomide (22% vs. 13%). The overall response rate was 53% for Len-refractory patients and 64% for non-Len-refractory patients in 2L therapy; median PFS was 10.7 vs. 18.3 months, respectively. Median overall survival (OS) was shorter for Len-refractory patients vs non-Len-refractory patients (23.8 vs. 53.6 months). Len refractoriness was an independent prognostic factor for both PFS and OS in Len-exposed patients. CONCLUSION: In this real-world Len-exposed cohort, Len-refractory patients receiving 1L Len experienced poorer survival outcomes than non-Len-refractory patients, highlighting the unmet need in this patient population which has driven the development of novel therapies.

Single-cell analysis of MYD88L265P and MYD88WT Waldenström macroglobulinemia patients.

Waldenström macroglobulinemia (WM) is characterized by the expansion of clonal lymphoplasmacytic cells; the MYD88L265P somatic mutation is found in >90% of patients, but malignant B cells may still display intra-clonal heterogeneity. To assess clonal heterogeneity in WM, we generated and performed single-cell RNA sequencing of CD19+ sorted cells from five patients with MYD88 L265P and two patients with MYD88 WT genotype as well as two healthy donors. We identified distinct transcriptional patterns in the clonal subpopulations not only between the two genetically distinct WM subgroups but also among MYD88 L265P patients, which affected the B cell composition in the different subgroups. Comparison of clonal and normal/polyclonal B cells within each patient sample enabled the identification of patient-specific transcriptional changes. We identified gene signatures active in a subset of MYD88L265P patients, while other signatures were active in MYD88 WT patients. Finally, gene expression analysis showed common transcriptional features between patients compared to the healthy control but also differentially expressed genes between MYD88 L265P and MYD88 WT patients involved in distinct pathways, including NFκΒ, BCL2, and BTK. Overall, our data highlight the intra-tumor clonal heterogeneity in WM with potential prognostic and therapeutic implications.

Diagnostic and Prognostic Value of Non-late Gadolinium Enhancement Cardiac Magnetic Resonance Parameters in Cardiac Amyloidosis.

Early diagnosis is crucial for the improvement of outcomes of patients with cardiac amyloidosis (CA). Emerging non-late gadolinium enhancement (LGE) based cardiac magnetic resonance (CMR) parameters may facilitate early identification of CA. We sought to investigate the diagnostic and prognostic value of T1, T2 mapping and extracellular volume (ECV) in CA. This single-center prospective analysis included 88 patients with CA, 33 patients with aortic stenosis (AS) and left ventricular hypertrophy (LVH), and 15 healthy controls who completed 3T cardiac MRI at the time of their diagnosis and were assessed with T1, T2 (modified Look-Locker inversion recovery), and ECV mapping of the heart and spleen. Echocardiographic, and biochemical parameters and clinical characteristics and outcomes were collected and analyzed. Of the patients with CA, 71 had light-chain (AL) and 17 had transthyretin (ATTR) amyloidosis. Native T1, native T2 and ECV were significantly higher in patients with CA compared to both patients with LVH-AS (P<0.001) and healthy controls (P<0.001). Good diagnostic accuracy was also demonstrated by measuring the area under the curve (AUC) of the receiver operating characteristic (ROC) curves for native T1 in the region of interest (ROI) (AUC=0.90), native T2 ROI (AUC=0.88), and ECV (AUC=0.90). Furthermore, native T1 ROI, native T2 ROI and ECV, correlated with both NT-proBNP levels and Mayo stage of patients (with AL). Spleen ECV was significantly increased in patients with AL versus ATTR amyloidosis (38.5 vs 30.5; P=0.004) and demonstrated good diagnostic accuracy in differentiating between the two types (AUC=0.79). Native T2 ROI was prognostic of mortality in AL CAwith a HR of 1.97 per 5 ms increase (P=0.001) and remained prognostic after adjustment for age, and Mayo stage. Non-LGE based CMR techniques correlated with established markers of disease and demonstrated good diagnostic accuracy, while native T2 ROI was also prognostic of mortality, thus reinforcing their use in the diagnosis and prognosis of CA.

Cardiovascular Toxicity of Proteasome Inhibitors: Underlying Mechanisms and Management Strategies: JACC: CardioOncology State-of-the-Art Review.

Proteasome inhibitors (PIs) are the backbone of combination treatments for patients with multiple myeloma and AL amyloidosis, while also indicated in Waldenström's macroglobulinemia and other malignancies. PIs act on proteasome peptidases, causing proteome instability due to accumulating aggregated, unfolded, and/or damaged polypeptides; sustained proteome instability then induces cell cycle arrest and/or apoptosis. Carfilzomib, an intravenous irreversible PI, exhibits a more severe cardiovascular toxicity profile as compared with the orally administered ixazomib or intravenous reversible PI such as bortezomib. Cardiovascular toxicity includes heart failure, hypertension, arrhythmias, and acute coronary syndromes. Because PIs are critical components of the treatment of hematological malignancies and amyloidosis, managing their cardiovascular toxicity involves identifying patients at risk, diagnosing toxicity early at the preclinical level, and offering cardioprotection if needed. Future research is required to elucidate underlying mechanisms, improve risk stratification, define the optimal management strategy, and develop new PIs with safe cardiovascular profiles.

Mutations in the alternative complement pathway in multiple myeloma patients with carfilzomib-induced thrombotic microangiopathy.

Thrombotic microangiopathy (TMA) has been reported to occur in multiple myeloma (MM) patients in association with treatment with carfilzomib, an irreversible proteasome inhibitor (PI). The hallmark of TMA is vascular endothelial damage leading to microangiopathic hemolytic anemia, platelet consumption, fibrin deposition and small-vessel thrombosis with resultant tissue ischemia. The molecular mechanisms underlying carfilzomib-associated TMA are not known. Germline mutations in the complement alternative pathway have been recently shown to portend increased risk for the development of atypical hemolytic uremic syndrome (aHUS) and TMA in the setting of allogeneic stem cell transplant in pediatric patients. We hypothesized that germline mutations in the complement alternative pathway may similarly predispose MM patients to carfilzomib-associated TMA. We identified 10 MM patients with a clinical diagnosis of TMA in the context of carfilzomib treatment and assessed for the presence of germline mutations in the complement alternative pathway. Ten, matched MM patients exposed to carfilzomib but without clinical TMA were used as negative controls. We identified a frequency of deletions in the complement Factor H genes 3 and 1 (delCFHR3-CFHR1) and genes 1 and 4 (delCFHR1-CFHR4) in MM patients with carfilzomib-associated TMA that was higher as compared to the general population and matched controls. Our data suggest that complement alternative pathway dysregulation may confer susceptibility to vascular endothelial injury in MM patients and predispose to development of carfilzomib-associated TMA. Larger, retrospective studies are needed to evaluate whether screening for complement mutations may be indicated to properly counsel patients about TMA risk with carfilzomib use.