Dispenzieri, Angela

Background: AL amyloidosis is a potentially fatal plasma cell dyscrasia. In a randomized phase 3 study (Kastritis E et al, NEJM 2021;385:46-58), the addition of daratumumab to cyclophosphamide, bortezomib and dexamethasone (Dara-CyBorD) significantly improved hematological and organ responses, and prolonged event-free survival (EFS). There was no overall survival (OS) difference at a median follow-up of 11.4 months. Methods: A retrospective study of AL amyloidosis patients seen at our institution between January 2018 and December 2022 who received upfront Dara-CyBorD or CyBorD. We excluded patients who received other forms of upfront therapy (including modifications of the above regimens, such as bortezomib-dexamethasone or daratumumab-dexamethasone). We compared the hematologic and organ responses, EFS and OS between the two treatment groups. Hematologic response was assessed at 2 and 6 months from therapy initiation, while cardiac and renal responses at 6- and 12-month landmarks. In all response evaluations, we included responses up to autologous stem cell transplantation (ASCT) if used or second-line therapy for any reason. For EFS analysis, an event was defined as death of any cause, hematological progression, end-stage cardiac or renal failure, or need for subsequent anti-plasma cell therapy in the absence of hematological progression. OS was calculated from the time of treatment initiation to death or last follow-up. Results: Among 641 newly diagnosed patients seen at our center between 2018 and 2022, 361 patients (56%) were included on intention-to-treat analysis [Dara-CyBorD =147 (41% of the cohort); CyBorD=214 (59%)]. There was no difference in the baseline characteristics between the treatment groups, including age, sex, difference between involved and uninvolved light chains, bone marrow plasma cells percentage, NT-proBNP and 24-hour proteinuria. The 2-month hematologic complete response (hemCR; 15.3% vs 4.4%, P<0.001) and very good partial response or better (≥hemVGPR; 62.2% vs 32.5%, respectively; P<0.001) were higher with Dara-CyBorD compared to CyBorD. At 6 months, the hemCR and ≥hemVGPR were again in favor of the Dara-CyBorD group compared to CyBorD (32.0% vs 13.7%, and 72.8% vs 46.7%, respectively; P≤0.002). The 6- and 12-month cardiac response rate in the Dara-CyBorD and CyBorD groups were 40.2% vs 22.6% (P=0.01) and 44.1% vs 23.2%, respectively (P=0.006). Cardiac ≥VGPR at the 6- and 12-month landmarks were statistically higher with Dara-CyBorD compared to CyBorD and increased in both arms between 6 and 12 months [20.5 % vs 9.3% (P=0.03) and 34.3 % vs 20.0% (P=0.04), respectively]. The 6-month and 12-month renal response to first-line therapy were numerically higher with Dara-CyBorD compared to CyBorD but were not statistically significant (48% vs 31.3%, P=0.10; 54.1% vs 30.1%, P=0.05). The 6 month and 12 months, renal ≥VGPR were numerically higher with Dara-CyBorD compared to CyBorD, again without statistical significance (26% vs 19.6%, P=0.63; 35.7% vs 17.2%, P=0.11, respectively). Treatment with Dara-CyBorD was significantly associated with lower 6-month mortality rate compared to CyBorD (8.8% vs 16.3%, P=0.04). With a median follow-up of 43.3 months (30 vs 59.4 months for Dara-CyBorD vs CyBorD, respectively; P<0.001), the two-year EFS was superior in the Dara-CyBorD group compared to CyBorD (69.1% vs 30.3%, hazard ratio (HR) 0.36, 95% confidence interval (CI), 0.26 to 0.48, P<0.001). The 2-year OS was also statistically higher in the Dara-CyBorD group compared to CyBorD (82.0% vs 69.6%, HR 0.53, 95% CI, 0.36 to 0.79, P=0.003). 148 patients (40.9%) proceeded to second-line therapy with a median of 5.1 months from first line therapy. To adjust for difference in follow-up time between the two treatment groups, we analyzed the second line therapy utilization at the 12-month mark which was statistically higher with CyBorD compared to Dara-CyBorD (42.9% vs 14.9%, P<0.001). Also, at 12 months, a higher proportion of patients treated with CyBorD received ASCT compared to Dara-CyBorD (24.3% vs 13.6%, P= 0.01). Conclusions: In this cohort of newly diagnosed AL amyloidosis patients in a large referral center, we confirmed higher hematological and organ response rates with Dara-CyBorD compared to CyBorD. We have also demonstrated that these higher response rates translate into a survival advantage of Dara-CyBorD over CyBorD.

Introduction The tumor ecosystem in multiple myeloma (MM) involves complex interactions among various cell types, including clonal plasma cells (PCs) and immune cells. Previous research has indicated that the bone marrow (BM) microenvironment's metabolite and lipid profiles differ between MM patients and those with precursor conditions. This study aims to explore if differences in cell composition, metabolic phenotype of clonal PCs, and the spatial organization of various cell types are linked to the early versus late progression of high-risk smoldering MM (SMM) to MM. Methods We identified high-risk SMM patients using the IMWG 20-2-20 criteria, focusing on early progressors (EP), who progressed to MM within one year, and later progressors (LP), who progressed after more than four years. Using a high-dimensional single-cell spatial imaging platform, CODEX (CO-Detection by indEXing), we identified clonal PCs and immune cell types as well as their metabolic phenotypes at the single-cell level, in paired FFPE BM samples at SMM diagnosis and at the time of progression to MM. Our validated panel included markers such as CD3e, CD4, CD8, CD14, CD20, CD31, CD38, CD45, CD66a, CD68, CD138, HLA-DR, ASCT2, pNRF2, GLUT1, LDHA, ATPA5, CPT1A, and Citrate synthase. We employed single-cell segmentation, artifact cleanup, signal thresholding, and spatial analysis. Repeated measure models accommodated multiple regions of interest (ROIs) per patient and accounted for potential intrapatient correlation, while Poisson models estimated incidence rate ratios (RR) of cell types. Spatial statistical models evaluated cell type segregation and integration at the time of SMM diagnosis. Results Single cell events were acquired from 6 unique SMM patients who had paired FFPE BM samples from the time of their SMM diagnosis and at the time of their progression to MM. There were 3 EP SMM patients (Time to Progression (TTP):8, 8, 10 mos) and 3 LP SMM patients (TTP: 51, 58, 117 mos). The median number of single cell events identified per patient slide sample was 104,390 (Range: 24,357 - 314,877). We identified 8 main cell types: PCs, CD4+ T-cells, CD8+ T-cells, B-cells, granulocytes, Monocyte/Macrophages and two groups of other immune cells. The PCs and the remainder of the non-PCs were further classified based on the expression of the following metabolic markers: ASCT2 (Glutamine importer), CPT1A (Fatty acid metabolism), GLUT1 (Glucose importer), LDHA (Glycolysis), Citrate synthase and ATPA5 (Oxidative Phosphorylation). There was a higher RR of granulocytes (RR 2.1, CI 1.6-2.8, p<0.001) in EP compared to LP samples at the time of SMM diagnosis, but a lower RR of CD4 T cells (RR 0.40, CI 0.3-0.6, p< 0.001). Focusing on metabolic phenotypes of the PCs, we observed higher incidence RR of most metabolic markers: ASCT2 (RR=1.77; p=0.032), ATPA5 (RR=1.25; p<0.001), CPT1a (RR=2.42; p=0.015), and LDHA (RR 2.13; p<0.001) in EP compared to LP samples at the time of SMM diagnosis. However, GLUT1 had a lower incidence RR in EP patients (RR=0.79; p<0.001). The same modeling for non-PCs at the time of SMM diagnosis yielded higher expression of LDHA (RR=1.98; p<0.001) and ASCT2 (RR=3.3; p=0.002). Using the x and y coordinates and the corresponding phenotype classifications, we performed spatial statistical modeling based on spatial point processes to generate aggregated measures of how different types of cells of interest interacted. CD4 T cells were more isolated in LPs compared to EPs (p =0.046). Segregation indices for PCs and CD4 T cells indicated that they were more integrated/collocated in EPs. Granulocytes were more isolated in EPs although the difference was not as pronounced (p= 0.07). PCs were more integrated with granulocytes (p=0.06) and B cells (p=0.07) in LP patients. Further analyses of paired samples at the time of progression to MM will be reported at the time of the presentation. Conclusion This study is the first to provide whole-slide, single-cell, spatial proteomic characterization of clonal PCs and immune cells in the FFPE BMs of high-risk SMM patients with varying progression times to MM. Distinct metabolic pathway markers in clonal PCs and their spatial relationships with immune cell subsets are closely associated with the risk of progression to MM. These findings illuminate the complex interactions between the metabolic states of clonal PCs and their spatial orientation relative to immune cells in the pathogenesis of MM.

Introduction: Ven is a BCL2 inhibitor that has shown clinical efficacy in RRMM patients (pts) particularly those that harbor t(11;14). Ven has been evaluated in clinical trials as a single agent, in combination with dexamethasone (dex), immunomodulatory drugs (IMiD), proteasome inhibitors (PI), and anti-CD38 monoclonal antibodies (MAb) yet its place in the therapeutic landscape remains in question. In this retrospective analysis, we aim to evaluate the real-world efficacy of Ven-based regimens in RRMM pts treated outside of a clinical trial across the 3-site MCCC. Methods: We retrospectively analyzed the medical records of pts with RRMM treated with Ven-based regimens between January 2015 and October 2023 at the MCCC. Refractoriness was defined by progression on or within 60 days of stopping treatment. Categorical variables were compared with Chi-square tests and continuous variables were compared with t-tests. Outcomes were estimated using the Kaplan-Meier method and curves were compared between the groups using log-rank tests. Results: 83 pts were included in the analysis. The median age was 71 (39-93), 63% were male, 93% were white, 27% had ISS III, 18% had high risk cytogenetics (HRCyto), 76% had t(11;14), the median prior lines of therapy (LOT) was 4 (1-15), 68% received ≥ 4 prior LOT, 87% received prior autologous transplant, 58% were triple-class refractory (TCR), 64%/23% were penta-drug exposed/refractory (PDE/R), 8% received prior BCMA-directed therapies (BDT), 58% received Ven+dex, 25% received Ven+PI +/-dex, 6 % received Ven+anti-CD38 MAb+/-dex and 11% received Ven+other. The median follow-up time from start of a Ven-based regimen was 29 months (mo). The median Ven dose was 800mg (20-1600) with 25% of pts receiving Ven ramp-up dosing. The overall response rate (ORR) to a Ven-based regimen was 58% and was 64% for pts with t(11;14) and 40% for pts without t(11;14); p=0.06. Ven-treated pts with HRCyto had inferior PFS (3mo) and OS (8mo) compared to patients who did not have HRCyto who had a PFS of 9mo (p=0.020) and OS of 80mo (p<0.001). The ORR for TCR and PDR pts were 52% and 42%, respectively. No significant ORR differences were noted across the different Ven-based regimens (p=0.32). The median PFS for pts with t(11;14) was 10mo compared to 2mo for pts w/o t(11;14); p=<0.001. The median OS for pts with t(11;14) was 80mo compared to 10mo for pts without t(11;14); p=0.001. Ven-treated pts who received 1-3 prior LOT has superior ORR, median PFS, and median OS; 89%, 25mo, and 99mo, respectively, compared to pts who received ≥4 prior LOT who achieved an ORR of 43% (p<0.001), median PFS of 5mo (p<0.001) and median OS of 25mo (p<0.001). Ven-treated pts that were TCR had inferior PFS (5mo) and OS (26mo) compared to pts who were not TCR who achieved a PFS of 12mo (p<0.001) and a median OS of 80mo (p=0.02).Ven-treated pts that were PDR had inferior PFS (4mo) and OS (22mo) compared to pts who were not PDR who achieved a PFS of 9mo (p<0.001) and a median OS of 80mo (p=0.02).Ven-treated pts who received prior BDT (n=7) achieved an ORR of 29% and had a median PFS and OS of 2mo and 6mo, respectively on a Ven-based therapy. 59 pts received additional therapy in the post Ven-progression setting. The ORR to post-Ven progression therapies was 53% (n=31/59), the median PFS was 9mo and median OS was 35mo. The most common post-Ven progression regimens used were PI-based (n=16; ORR=56%), anti-CD38 MAb-based (n=14; ORR=50%), BDT (n=12; ORR=83%), selinexor-based (n=3; ORR=0%) with BDT resulting in highest ORR (p=0.048) and PFS (p=0.005). Conclusions: Ven-based regimens are effective in heavily pre-treated pts with RRMM however they are more effective when used within 1-3 prior LOT, in pts with t(11;14), and in pts without HRCyto, TCR or PDR MM. BDT appear to be the most efficacious therapies in the post-Ven progression setting.

Introduction: Uniform assessment of response to treatment is crucial to managing myeloma and developing new therapies. Measurement of the monoclonal protein (s) secreted by the myeloma cells forms the cornerstone of disease assessment in MM and has primarily been performed by electrophoretic methods in the serum and urine, as well as assessment of free light chains in the serum. According to international myeloma working group (IMWG) guidelines, serial serum-free light chain (sFLC) is included in MM response assessment to define stringent complete response and for evaluating partial response (PR) or progressive disease (PD) in non/oligo-secretory MM. This study aims to determine the added value of serial sFLC measurements in monitoring response and progression in MM with measurable disease by comparing the kinetics of FLC with M spike measured by electrophoresis in serum or urine. Methods: This retrospective observational study included newly diagnosed MM patients evaluated at Mayo Clinic in Rochester between 2011-2021. All patients had measurable sFLC (involved FLC level ≥ 10mg/dL, with abnormal sFLC ratio) along with measurable M-protein by serum or urine protein electrophoresis at diagnosis. Serial measurements of sFLC and M-protein by electrophoresis (sPEP/uPEP) were prospectively collected from the electronic medical records at different time points. FLC-response and FLC-PD were evaluated based on IMWG criteria. Results: The study cohort included 839 patients, 52% with measurable M protein by electrophoresis in serum, 27% in both serum and urine, and 21% in urine-only. A significant association was observed between sFLC and electrophoretic response during the induction and at the time of best response (p <.001). Serum FLC showed a comparable response rate of 98% (≥ PR) at the time of best electrophoretic response (p <.001). Ninety-nine percent of early FLC responders eventually achieved an overall response by sPEP/uPEP (p <.001). In the urine-only group, 99% achieved at least a PR by uPEP, and all showed at least a PR based on sFLC. We observed comparable median percentage changes in serial dFLC and urine M-protein, with parallel trends (p <0.001). The correlation coefficients between the change of sFLC and urine M-protein showed a moderate/strong correlation with coefficients (r) of 0.791, 0.597, 0598, 0.545, after cycles 1, 2, 3, 4, respectively, (p < .001). The response for all cohorts was detected earlier by dFLC (median time 1.1 months, 95% CI: 1.06-1.17), in comparison with serum M-protein (1.5 months, 95% CI: 1.40-1.62) and urine M-protein (2.8 months, 95% CI: 2.42-3.10) with p < .001. In the urine-only group, earlier detection of response by dFLC (1.1 months, 95% CI: 1.00-1.2) was observed, compared to urine M-protein (2.4 months, 95% CI: 2.00-2.7) (p <.001). After a median follow-up of 52 (IQR 27.6, 72.3) months, 56% had PD: 62% by s-FLC, 56% by serum M-protein, and 24% by urine M-protein. Among patients with PD by uPEP, all except one patient met sFLC-PD. Within patients with PD, sFLC was the only detectable tumor marker in 12% of cases at the time of the second line of treatment. After four cycles of induction, there was no difference in PFS between VGPR response determined by sFLC, sPEP, and uPEP (p =0.538). The median second-PFS for patients with onlysFLC-PD was similar to those with urine M-protein PD with or without sFLC-PD (HR 1.28, 95% CI =0.77-2.13. p 0.334). However, the median overall survival (OS) from the first relapse was significantly better for patients with onlysFLC-PD than those with urine M-protein PD (HR 1.87, 95% CI =1.07-3.27. p 0.026). Conclusions: In this study, achieving sFLC-VGPR has a similar impact on PFS as electrophoretic-VGPR after induction, indicating that serial sFLC can potentially replace the requirement for urine M-protein response (< 100mg in 24-hours urine) as part of the electrophoretic-VGPR criteria, as required by IMWG. A similar response rate between sFLC and urine paraprotein confirms the current cutoffs (90% for urine and 50% for dFLC for VGPR) used for response categories for s-FLC. We also observed that in 12% of patients with PD, sFLC was the only marker of progression, highlighting the value of serial s-FLC in monitoring relapse. In conclusion, our study supports the integration of serial sFLC measurements for monitoring response and progression in MM, even with electrophoretic measurable disease.

Introduction: Light-chain (AL) amyloidosis is caused by the secretion of immunoglobulin light chains by monoclonal plasma cells. The increase in the levels of these monoclonal proteins may proceed the development of any clinical symptoms, and their identification in the serum and urine remains an integral part of establishing a diagnosis of AL amyloidosis. This systematic review aims to evaluate the diagnostic test accuracy of serum immunofixation (SIFE), urine immunofixation (UIFE), and free light chain (FLC) ratio for the diagnosis of AL amyloidosis. Methods: As part of the ASH AL Amyloidosis Diagnostic Guideline, we performed systematic reviews for 7 prioritized PICO questions related to the screening, diagnosis and organ involvement evaluation of AL amyloidosis. Electronic searches were conducted on PubMed, Embase, and the Cochrane Central Register of Controlled Trials from inception till January 2024. Two reviewers independently and in duplicate performed title and abstract screening and full text article screening on LASER AI, with conflicts resolved by a third reviewer. Eligible studies were those that included patients who performed one of the three tests (SIFE, UIFE, and κ/λ FLC) and had their AL amyloidosis diagnosis confirmed via a biopsy. Diagnostic test accuracy measures of interest were sensitivity, specificity, positive and negative predictive value. Statistical analysis was performed on OpenMeta[Analyst]. Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to assess the certainty of evidence. Results: After deduplication, we retrieved 29,237 studies from electronic databases. 31 studies with 3973 patients reported on the use of serum immunofixation (SIFE) with a pooled sensitivity of 72.4% (95% CI 68.1%-76.4%). 27 studies with 2855 patients reported on the use of urine immunofixation UIFE for the diagnosis of AL amyloidosis with a pooled sensitivity of 78.6% (95% CI 74.6%-82%). 29 studies with 5305 patients reported on the use of κ/λ FLC ratio amyloidosis with a pooled sensitivity of 79.9% (95% CI 73.7%-84.9%). 24 studies reported on the use of both SIFE and UIFE with a sample size of 3751 patients and a pooled sensitivity of 90% (95% CI 85.3%-93.3%). 3 studies reported on the use SIFE and κ/λ FLC ratio with 321 patients and a pooled sensitivity of 97.7% (95% CI 95.6%-99.9%). Finally, we identified 10 studies that performed SIFE,UIFE, and κ/λ FLC ratio concurrently with 1926 patients and a pooled sensitivity of 99% (95% CI 97%-99.7%) of all three tests and considering a result abnormal if any of the components had a positive result. We also identified 5 studies with 957 patients reporting on the concurrent use of SIFE, UIFE, and κ/λ FLC ratio for the diagnosis AL amyloidosis and differentiation of AL from ATTR amyloidosis in a population of patients with suspected cardiac amyloid involvement, the pooled sensitivity was found to be 99%(95% CI 99%-100%) and with a pooled specificity of 77%(95% CI 75%-80%). Certainty of evidence moderate for all outcomes. Conclusion: The combined use of SIFE, UIFE, and κ/λ FLC ratio has a high sensitivity for the diagnosis of AL amyloidosis, and the tests remain a valuable initial screening of AL amyloidosis and differentiation from ATTR amyloidosis.

Introduction: In patients with systemic light-chain amyloidosis, cardiac involvement is common. Cardiac involvement (presence and severity) is the most important predictor of mortality in patients with AL amyloidosis. Endomyocardial biopsy remains the gold standard, but it is a costly and invasive test. Consequently, cardiac biomarkers are used for screening for cardiac involvement and have significant prognostic value.In this systematic review, we aim to estimate the diagnostic test accuracy (DTA) of Nt-proBNP, BNP, and high sensitivity troponin for cardiac amyloidosis. Methods: As part of the American Society of Hematology guidelines on the diagnosis of Amyloidosis, we searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials from inception till January 2024 for relevant studies. Two reviewers independently performed title and abstract screening and full-text article screening on LASER Al and extracted relevant data using piloted Excel sheets. The panel judged whether the reference test is acceptable or not. Acceptable reference test is EMB alone or a combination of extracardiac biopsy plus cardiac imaging (CMR or echocardiography) with or without positive cardiac biomarkers (troponin or BNP or NT-proBNP). For statistical analysis, we only included studies reporting on both the sensitivity and specificity of the cardiac biomarker. We used Stata 18.0 software for meta-analysis. We evaluated risk of bias using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) and used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach to assess the certainty of the evidence. We report diagnostic test accuracy as sensitivity (95% confidence interval) and specificity (95% confidence interval). Results: After screening 29,237 studies, a total of 10 studies addressed DTA of Nt-proBNP for cardiac amyloidosis. These studies used a wide variety of cutoffs for diagnosis of cardiac involvement, ranging from 150 to 5000 ng/L and a cutoff of 332 ng/L was the most studied and reported. The pooled estimates for sensitivity and specificity of Nt-proBNP using 332 as cutoffs are 0.99 ( 0.97, 1) and 0.53 (0.3, 0.75), respectively. The pooled estimates were based on 4 studies (n=645) with moderate certainty in the evidence. For BNP, DTA was assessed in 3 studies (n= 257). Each study used a different cutoff for BNP (73, 100, and 412 ng/L). The sensitivity and specificity of BNP in each study were comparable and not significantly affected by the cutoff variation. Pooled sensitivity and specificity across studies, were 0.87 (0.80, 0.92), and 0.79 (0.71, 0.85), respectively. The certainty in evidence for the DTA of BNP was low. Eight studies reported on DTA of high sensitivity troponin, with cutoffs ranging from 14 to 86 ng/L. Meta-analysis of studies reporting on cutoff 14 ng/L yielded sensitivity of 0.94 (0.87, 0.97) and specificity of 0.11 (0.08, 0.16) with moderate certainty evidence. Increasing the cutoff to 35 ng/l led to a decrease in sensitivity to 0.82 (0.66, 0.92) and an increase in specificity to 0.86 (0.74, 0.93) with low certainty evidence. Conclusion: Cardiac biomarkers are highly sensitive, valuable initial tests for increasing suspicion of cardiac involvement in patients with AL amyloidosis. However, they lack specificity and, on their own, are insufficient for a definitive diagnosis of cardiac involvement. These biomarkers may be used in conjunction with other diagnostic tests to accurately identify and assess the extent of cardiac involvement.

Background: Despite substantial improvements in early mortality (EM) for patients with systemic light chain amyloidosis (AL), rates remained high in the bortezomib-era, at approximately 25% (Muchtar et al. Blood. 2017). However, the therapeutic landscape in AL amyloidosis has changed with the ANDROMEDA trial, which led to the approval of daratumumab in combination with bortezomib, cyclophosphamide, and dexamethasone (Dara-VCd) in the frontline setting. The incidence and predictors of EM in the context of daratumumab-based frontline therapy have not been studied. Methods: We performed an international multicenter retrospective cohort study of all consecutive patients with newly diagnosed AL treated with frontline Dara-VCd or Dara-Vd, and followed until 12/31/2023. EM was defined as death from any cause within 6 months of treatment initiation. Our primary objective was to identify the rate and significant predictors of EM. Univariate logistic regression was used to identify significant predictors of EM, which were then included in a multivariate logistic regression model. The receiver operator characteristic (ROC) analysis was used to determine the best threshold values that discriminated EM rates for the following continuous variables: age, dFLC (involved-uninvolved), eGFR, NT-proBNP, albumin, and high-sensitivity Troponin-T (hs-TnT). Other variables tested in univariate analysis were the following: ECOG performance status, NYHA functional class, sex, race, light chain isotype, percent bone marrow plasma cells, status of the following cytogenetic abnormalities-t(11;14), +1q, hyperdiploidy, del(13q), high-risk translocations, and del(17p), and the number of organs involved (2 vs 1). To build the clinical prediction score, each variable was weighted according to the β coefficient (natural logarithm of odds ratio) obtained from the multivariable regression. The β coefficients were rounded to the nearest 0.5 and multiplied by 2 to obtain an even number. Results The study cohort included 335 AL patients treated with daratumumab-based frontline therapy (92.2% Dara-VCd, 7.8% Dara-Vd), with all surviving patients having at least 6 months of follow-up. The median age at diagnosis was 66.5 years (range, 59.4 - 71.3), and 6.7% (n = 22) were Non-Hispanic blacks. Median dFLC at diagnosis was 22.91 mg/dL (range, 0.2-1093.4), and median NT-proBNP was 2415 pg/mL (range, 13-70,000). Mayo 2004 stages IIIA/IIIB represented 44% of the total cohort, with 17% having ECOG ≥ 2 and 25.4% having NYHA Class III/IV symptoms. The cumulative incidence of EM was 10.7%, with the incidence in patients with Mayo 2004 stage I, II, IIIA, and IIIB being 0%, 8%, 12.5%, and 25% respectively. On univariate analysis with unadjusted odds ratio (OR), the following variables significantly predicted EM: Age ≥ 75 (OR=2.8, p=0.013) ECOG ≥ 2, (OR 4.9, p<0.001), NYHA Class ≥ III (OR=4.95, p<0.001), dFLC ≥9 mg/dL (OR, 10.18, p=0.023), eGFR <33 mL/min/1.73 m2 (OR=2.7, p=0.026), NT-proBNP >5276 pg/mL (OR=7.69, p <0.001), hs-TnT >70 ng/L (OR=5.88, p<0.001), and absence of t(11; 14) (OR=2.33, p=0.041). These variables were entered into multivariate regression, except for ECOG and NYHA, which were combined to create a single variable (values ranging from 0-8), and hs-TnT was dropped due to substantial missing data as centers used different troponin assays. NT-proBNP was rounded to 5300 pg/ml for ease of clinical application. Based on the multivariate analysis, the following scores were assigned to each variable: Age ≥75 (2.0), ECOG+NYHA (1.0 x combined score), NT-proBNP >5,300 pg/ml (2.0), and absence of t(11;14) (3.0). This led to a score ranging from 1-15, and two risk-groups: low-risk (score <9; 87.5%) and high-risk (score ≥9; 12.5%). The respective cumulative incidence of EM was 6.1% versus 50% (p<0.001). The c-index of the model was 0.725 (95% CI, 0.676-0.774). Conclusion: Using variables that are readily available in the clinic, we have developed a two-tiered risk-prediction model for EM in AL amyloidosis in the context of daratumumab-based frontline therapy. The model needs to be externally validated in an independent dataset.

Background Multiple myeloma (MM) is a hematological cancer characterized by the proliferation of plasma cells (PC). Progressive disease (PD) criteria are primarily characterized by an increase in (1) serum M-protein (SPEP), (2) urinary M-protein (UPEP), (3) serum free light chains (sFLC), or (4) PC percentage in the bone marrow. An essential aspect of the PD criteria is the requirement for confirmatory results from blood or urine analyses. However, in many cases, patients may be taken off treatment in favor of a new therapy after only one assessment. This can introduce clinical trial endpoint inaccuracies when confirmatory values are missing, resulting in increased censoring and underestimation of the progression rate (if the second assessment is not done). Moreover, in subjects with high tumor burden and rapidly progressing disease, it is often urgent to confirm PD before starting a subsequent line of treatment. This study assessed the necessity of repeating biomarkers to confirm PD if two biomarkers meet the progression criteria. Methods In this retrospective study, between 2002 and 2020, we assessed all consecutive patients with relapsed MM enrolled in any therapeutic clinical trial at Mayo Clinic. We included patients with measurable disease if SPEP and sFLC were available at the time of assessment. Patients required at least two consecutive assessments (by the same method) to be included in our study. PD was based on the IMWG criteria. Relapse characterized by the development of new bone lesions or extramedullary relapse without meeting biochemical progression criteria was an exclusion criterion. Patients starting a new line of treatment after non-confirmed PD were also excluded. Furthermore, patients who did not meet simultaneous progression criteria and had unconfirmed PD (did not meet IMWG criteria at the second assessment) were excluded from the analysis (n=15). The probability of meeting the progression threshold with 1 and 2 consecutive assessments was calculated. We then examined the proportions of patients meeting PD by 2 biomarkers simultaneously at the first assessment. Results We evaluated episodes of treatment among 434 patients enrolled in clinical trials, including 601 episodes: 593 episodes of biochemical confirmed PD and 8 episodes when patients did not progress but who met simultaneous progression criteria at the same time with two different biomarkers. Per measurable disease criteria, MM isotypes were 71.0% IgG, 16.8% IgA, 0.9% IgM, 1.2% IgD, 0.3% biclonal, and 9.8% light chain. According to the standard IMWG response criteria (sequential criteria), 78% and 9% of episodes reached the progression threshold with serum and urine M-components, respectively, with two consecutive assessments. For the FLC, 21% of episodes met the progression criteria. No patients had a second bone marrow examination for confirmation of PD. At the first available assessment, 82%, 19%, and 2% of episodes met progression threshold, respectively, with serum M-protein, urine M-protein, and both (serum + urine M-protein). Additionally, 58%, and 19%, episodes met the progression threshold at the first assessment with FLC and bone marrow examination, respectively. Moreover, 67% of patients with IgA myeloma meet the progression threshold with the total quantitative IgA. With the simultaneous criteria at time of first assessment, 403 episodes meet progression threshold: 45% with SPEP+sFLC (n=269/593), 4% with SPEP+UPEP (n=21/593), 9% with sFLC+UPEP (n=55/593), 11% with BME only (n=66/593), and 0.3% with qIgA +dFLC/UPEP (n=2/593). Thus, among these 413 episodes, which meet progression criteria by 2 simultaneous values at the time of the first assessment, 98% (n=413/(413+8)) of these patients (positive predictive value of the new criteria) subsequently had confirmed progression by sequential value. Conclusions In summary, we showed that the simultaneous criteria allow to identify patients with true progressive disease without overestimating the progression rate of myeloma. Therefore, confirmatory results of progression for relapsed MM patients having two biomarkers meeting criteria of progression at the same time is useless for determining disease progression.

Background: Light chain (AL) amyloidosis is a rare and understudied plasma cell disorder. It is caused by abnormal misfolding of monoclonal immunoglobulin light chains, leading to extracellular deposition of amyloid, ultimately resulting in organ dysfunction and death. Since AL amyloidosis is uncommon, therapies are adapted from the more common plasma cell disorders like multiple myeloma. Daratumumab, a monoclonal antibody targeting CD38, was first tested in several prospective and retrospective studies in AL patients with relapsed refractory disease. The ANDROMEDA study (Kastritis E et al, NEJM 2021) established daratumumab in combination with CyBorD (Cyclophosphamide-Bortezomib-Dexamethasone) followed by daratumumab maintenance as the new standard of care compared to CyBorD alone for newly diagnosed patients. Consequently, daratumumab maintenance has become universally offered to all newly diagnosed AL amyloidosis patients. Notably, there was no second randomization before the initiation of maintenance therapy in ANDROMEDA. Hence, a critical question that remains is whether the superior efficacy observed in the investigational arm of the ANDROMEDA trial is solely a result of the addition of daratumumab during the induction phase or if the maintenance phase contributed to the favorable outcomes in the investigational arm. We hypothesize that a shorter duration of maintenance would prove non-inferior to the standard duration of daratumumab maintenance in patients with AL amyloidosis that have responded to Daratumumab-CyBorD induction. To answer this question we are conducting a pragmatic phase 2 randomized trial assessing the optimal duration of daratumumab maintenance in patients with AL amyloidosis who have responded to Daratumumab-CyBorD induction. Study Design, Patients and Methods: We use broadened eligibility criteria consistent with pragmatic trial design. The estimated total enrollment is up to 96 patients. The main eligibility criteria are patients with biopsy-proven AL Amyloidosis who have completed 6 cycles of Dara-CyBorD-based induction treatment and achieved an adequate response to induction (defined as hematological complete response (CR), hematological very good partial response (VGPR), or hematological partial response (PR) with at least one organ response). Patients in whom bortezomib and/or cyclophosphamide were omitted from induction due to toxicity concerns or adverse effects are allowed. The major exclusion criteria are patients who were concomitantly diagnosed with multiple myeloma based on International Myeloma Working Group (IMWG) criteria. This phase II, open-label, multicenter trial (NCT05898646) randomizes patients who have attained an adequate response to 6 cycles of Dara-CyBorD-based induction in a 1:1 ratio, using a dynamic allocation procedure that balances the marginal distributions of the stratification factors (age, cardiac stage, and t(11;14) status). Randomization is to either single-agent daratumumab maintenance of 6 cycles duration (experimental arm) or 18 cycles of daratumumab maintenance (control arm) (cycle = 28 days). Treatment is allowed to be given at a local facility After completing maintenance treatment, patients will follow up every 3 months for up to 36 months from registration. The primary endpoint of the trial is to evaluate the non-inferiority of a shorter (6 cycles) daratumumab maintenance measured by event-free survival (EFS) compared to the standard maintenance of 18 cycles in newly diagnosed AL amyloidosis who receive 6 cycles of daratumumab-CyBorD based induction. EFS in this study is defined as time from registration to any of the following events: hematological progression, organ progression, subsequent anti-plasma cell therapy in the absence of hematological progression but with persistent organ dysfunction or death, whichever occurs first. Secondary endpoints are depth of hematological and organ response, bone marrow measurable residual disease negativity rate, duration of response, quality of life, and survival. By investigating whether a shorter duration of maintenance is non-inferior to the standard duration, we aim to inform clinical practice and potentially reduce the toxicities associated with prolonged maintenance therapy, including hypogammaglobulinemia, recurrent infections, the need for intravenous gammaglobulin replacement, and financial toxicity.

Introduction. Platelet-activating anti-Platelet factor 4 (PF4) antibodies mediate a number of thrombotic thrombocytopenic syndromes, including heparin-induced thrombocytopenia (HIT), and more recently recognized conditions, vaccine-induced immune thrombotic thrombocytopenia (VITT), adenovirus-associated thrombotic thrombocytopenia, and monoclonal gammopathy of thrombotic significance (MGTS). In MGTS (Blood. 2023 Apr 6;141(14):1772-1776), a monoclonal IgG antibody to PF4 mediates a chronic prothrombotic state characterized by recurrent thrombosis. More recent evidence suggests that MGTS may present with negative results in HIT enzyme-linked immunosorbent assay (ELISA) and serotonin release assay (SRA), and positivity only in PF4-dependent functional assays such as the PF4-dependent P-selectin expression assay (PEA; submitted). The presence of MGUS in patients has long been associated with high risks of thrombotic disease (Blood. 2010 Jun 17;115(24):4991-8), but the mechanism by which they predispose to thrombosis has been relatively unexplored. In this study, we evaluated a cohort of MGUS patients who experience thrombosis for the presence of platelet-activating anti-PF4 antibodies. M ethods. An administrative database search was performed of Mayo Clinic records to identify patients who had a diagnosis of MGUS, and thrombosis. Research samples from 134 MGUS patients with IgG monoclonal protein and thrombosis were obtained from Mayo Clinic's dysproteinemia biobank and subjected to PF4 antigen-based and functional screening. Research studies were approved by the Institutional Review Board of Mayo Clinic. Results. Of the 134 patients, 17 (12.7%) activated platelets in the PEA (≥19%). To exclude non-specific activation (e.g. due to HLA antibodies), secondary PEA testing was performed to assess whether platelet activation was mediated by a HIT-like antibody (i.e., PF4- and IgG-dependent, and inhibitable with high concentrations of heparin). Four patients, hereafter referred to as patients 1-4, were identified as having a HIT-like antibody, as demonstrated by PF4-dependent platelet activation that could be inhibited with high concentrations of heparin (100 U/mL), and blockade of the platelet IgG receptor, FcγRIIa. Patients 1 and 2 had persistent, platelet-activating anti-PF4 antibodies based on PEA testing of multiple samples obtained several years apart. Patient 1 had a recurrent, multi-year history of deep venous thrombosis (DVT), while patient 2 had one DVT episode. Patient 3 demonstrated a HIT antibody-like profile in the PEA in two of three samples available for testing and had a history of thrombotic cerebrovascular accident (CVA). Patient 4 demonstrated a HIT-like platelet-activating antibody in only one of four samples tested, and consistent with this finding, had an MGUS identified on clinical testing at only one time point (“small” IgG lambda, not quantified), 3 months prior to the platelet-activating sample. This patient experienced multiple thrombotic events including DVTs, left atrial thrombus and embolic CVA, pulmonary embolism and acute limb ischemia. All patients tested negative in two FDA-approved antigen-based HIT assays tested (Immucor PF4 IgG and Zymutest HIA IgG), similar to a recent MGTS case (submitted). SRA was negative in both Patients 1 & 2, weakly positive in Patient 3 (33%, with high CV), and positive (72%) in Patient 4. Conclusions. Definitive diagnosis of patients with MGTS provides insight into a mechanism of “unexplained” thrombosis and may offer additional treatment pathways for these patients with recurrent thrombosis (New Eng J of Med, 2024 Aug 8). Serologic testing in two patients correlated strongly with observations of thrombosis, and the study confirmed recent findings that anti-PF4 antibodies may present with unusual serology that is neither HIT- nor VITT-like (with negative results in both ELISA and SRA). The incidence of confirmed/suspected MGTS was 3% (4/134) in this population of MGUS patients with thrombosis. Prospective studies are needed to confirm these observations.