Citations 999

A US Retrospective Observational Study of Rituximab Use in Cold Agglutinin Disease

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 3835-3835

10.1182/blood-2023-172563

Background Cold agglutinin disease (CAD) is a rare autoimmune hemolytic anemia (AIHA). Rituximab is approved for treatment of B-cell lymphoma and severe rheumatoid arthritis and used off-label as a treatment for AIHA, including CAD. There is limited real-world evidence on patterns of rituximab use, safety, response rate and duration of response among patients with CAD. Objectives The key objectives were: 1) to characterize patients who initiated rituximab and examine their treatment patterns; 2) to describe the incidence of serious infections (SIs) prior and post rituximab treatment; 3) to assess the rate and duration of response to rituximab using hemolytic markers. Methods This retrospective, cohort study included adult (aged ≥18 years) patients with CAD from Optum's de-identified Market Clarity Data (2007-2021). Patients with CAD (Cohort 1) were indexed on their CAD diagnosis date. Cohort 1 patients who had ≥1 rituximab infusion (Cohort 2) were indexed on their 1 st rituximab infusion date ( Figure 1). Patients with cold agglutinin syndrome associated comorbidities on or before their index date were excluded. For each cohort, demographics, and clinical characteristics at index date, and for Cohort 2, clinical characteristics during 1 year before index date were described. Data for rituximab treatment patterns included number of courses, treatment type (monotherapy or combination therapy), complete or incomplete course, and the use of blood transfusion (BT) as rescue therapy. In Cohort 2, the incidence rates of SIs per 1000 patient-years before and after treatment (within 6 months of 1 st infusion) were assessed. Response to treatment was assessed using hemolytic markers (hemoglobin [Hb], bilirubin, and lactate dehydrogenase [LDH]). From baseline, a change of ≥2 g/dL was considered a Hb response, while a decrease of 50% was assessed as proxy for a bilirubin or LDH response. Relapse was defined as the reversal of biomarker levels below the minimum response threshold. Response duration was the period from the date of response to that of relapse. Results A total of 611 CAD patients were identified (Cohort 1); 94 of them received rituximab (Cohort 2). Median time from CAD diagnosis to rituximab initiation was 43.5 (Interquartile range [IQR]: 13.0-308.3) days. Overall, Cohort 2 had a more severe disease status at treatment initiation than all patients with CAD (Cohort 1) at diagnosis (higher comorbidity scores, rates of health care resource utilization, lower Hb, and more severely elevated hemolytic markers; Table 1). In Cohort 2, the mean (SD) number of rituximab courses per patient was 1.45 (1.16); 24 (25.5%) of patients had ≥1 incomplete course; 37 (39.4%) required BT rescue therapy, and the median time from rituximab initiation to 1 st BT was 31 (IQR: 1.5-110.5) days. Combination therapy was rarely used (3/94; 0.03%); only 1 patient completed. The incidence rate (95% CI) of SIs (per 1000 patient-years) post CAD diagnosis in Cohort 2 was ~3 times higher in the 4 to 6 months after rituximab initiation (637.1 [242.2-1032.0]) than before (245.4 [125.1-365.6]). Proportion of corticosteroid use was the same during 1 year prior to rituximab initiation and concomitantly with rituximab (54/94; 57.4%, both). For patients in Cohort 2 with available data, 69.5% (41/59) had a Hb response, 59.6% (28/47) had a bilirubin response, and 31.3% (10/32) had a LDH response to the 1 st course of rituximab (median [IQR] time to response: 48.0 [33.5-85.0], 68.0 [33.3-199.8], and 67.5 [45.3-211.3] days, respectively). Among patients who responded to the 1 st course, Hb relapse occurred in 68.3% (28/41), bilirubin relapse in 53.6% (15/28), and LDH relapse in 80.0% (8/10) of patients (median [IQR] time from response to relapse: 44.0 [13.3-90.8], 98.00 [29.0-257.0], and 93.00 [21.3-161.8] days, respectively). Conclusions The findings highlight outcomes of rituximab use for treatment of CAD in a real-world setting. Patients who initiated rituximab had more severe disease compared to all patients with CAD. Rituximab was predominantly given as monotherapy, with an average of 1.45 courses per patient. About 25% of patients had ≥1 incomplete rituximab course, and rescue therapy with BTs was often required. Patients receiving rituximab experienced 3 times more SIs after initiating rituximab than before treatment. Although responses to rituximab were commonly observed, duration of response was short, and the rate of relapse was high.
The Impact of Melphalan Conditioning Schedule on Post-Transplant Outcomes in AL Amyloidosis: A Multicenter Study with 1718 Patients

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 4784-4784

10.1182/blood-2023-188115

Introduction: High dose chemotherapy and autologous stem cell transplantation (ASCT) is one of the most effective therapies in light chain (AL) amyloidosis. It is associated with a high hematologic response rate and leads to durable remissions. High dose melphalan is the most frequently used conditioning chemotherapy, as has been used in multiple myeloma (MM). Melphalan dose is based on renal function, age, degree of cardiac involvement and patients' frailty and is predictive of outcomes. While studies that assessed the conditioning schedule have been conducted in MM, with variable results, no such studies were done in AL amyloidosis. Methods: In this retrospective study, we explored the impact of the conditioning schedule on post-transplant outcomes in a large multicenter study. Patients with AL amyloidosis who underwent ASCT for the primary diagnosis of AL amyloidosis between January 1, 2003, and December 31, 2020, were included in this study. Results: One thousand seven hundred and eighteen (n=1718) patients from 9 centers are included. The median age was 58 years, and 61% were male. Most patients had one (43%) or two (33%) involved organs, with the most involved organs were the kidneys (69%) followed by the heart (52%). Induction therapy was given to 52% of patients. The conditioning regimen was almost exclusively melphalan (99.2%), with 65% receiving full dose melphalan (≥170 mg/m 2). Melphalan was given over two days in most patients (80%). A rest day between conditioning and stem cell infusion was provided in 53% of patients, mostly in those who received melphalan on a single day rather than over 2 days (87% vs 44%, P<0.001). Post-transplant hematologic response was available for 1569 patients (91% of patients) and were assessed from baseline. Complete response (CR) and very good partial responses (VGPR) were achieved post-ASCT in 33.7% of patients each. Low dFLC-partial response (PR) was achieved in 2.7% and PR in 18% of patients. Altogether, satisfactory post-ASCT response (CR, VGPR, or low-dFLC PR combined) was achieved in 70% of patients. Compared to no induction, less than a PR to induction was associated with a lower probability of achieving satisfactory post-ASCT response, while PR or better to induction had higher chances of satisfactory post-ASCT response (65% vs 46% vs 84%, P<0.001). A single day of melphalan conditioning was associated with a higher probability of satisfactory post-ASCT response compared to two days of conditioning (82% vs 67%, P<0.001). Omitting a day of rest between conditioning and stem cell infusion was also associated with higher satisfactory post-ASCT response compared to having a rest day (76% vs 65%, P<0.001). The Table lists other predictors for a post-ASCT satisfactory hematologic response. In a nominal multivariate logistic regression analysis, independent predictors for higher post-ASCT satisfactory hematological response rate included: PR or better to induction therapy, female gender, kappa light chain isotype, lower dFLC at baseline, and kidney and liver involvement. In addition, full dose melphalan, conditioning given over a single day and having no rest day between conditioning and stem cell infusion were also associated with a higher likelihood of satisfactory post-ASCT response. Post-ASCT hematologic CR rate was higher in those receiving full dose conditioning (36% vs 28%, P<0.001), in those having no rest day (40% vs 28%, P<0.001) but not in those who received one day of conditioning versus two days (35% vs 33%, P=0.5). The rate of ICU admission was higher in those receiving no day rest (17.7% vs 12.6%), P=0.003) and among those who received reduced dose melphalan (18.1% vs 13.3%, P=0.008) but not based on number of conditioning days (P=0.56). Day 100 mortality was significantly higher in the no rest day group (5.6% vs 3.2%, P=0.01) and among those receiving reduced dose melphalan (6.8% vs 3.1%, P=0.004) compared to their counterparts, but not based on the number of days of conditioning (P=0.89). The median follow-up in the entire cohort was 104 months (95% CI 98-110). In a multivariate analysis for overall survival (OS), the conditioning dose but not the conditioning schedule was independently associated with OS. Conclusions: This study is the first to demonstrate the effect of melphalan conditioning schedule on post-transplant response. This study supports a single day melphalan conditioning in AL amyloidosis to improve post-ASCT response.
Modified Staging System for Waldenström Macroglobulinemia (MSS-WM): A Multi-Institutional Externally Validated Prognostic Model for Active/Symptomatic Waldenström Macroglobulinemia

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 3030-3030

10.1182/blood-2023-179940

Background: Waldenström Macroglobulinemia (WM) is an indolent lymphoma with heterogeneous outcomes. The recently developed, Revised International Prognostic Scoring System for WM (rIPSS-WM) did not examine the prognostic impact of MYD88L265P, a somatic alteration present in most patients with WM. Moreover, rIPSS-WM could only be partially validated in an external cohort. Here, we report the performance of rIPSS-WM and propose a refined prognostic model with external validation. Methods: We reviewed medical records of treatment-naïve patients with active WM consecutively seen at Mayo Clinic, Rochester (MCR) between 01/01/1996 and 12/31/2017. We applied the rIPSS-WM model in patients with data available for all required parameters, including age, serum beta-2 microglobulin (β2M), serum lactate dehydrogenase (LDH) and serum albumin at diagnosis to assess the prognostic utility of this model. We then identified the dichotomized clinical and laboratory parameters prognostic for overall survival (OS) by univariate analyses (UVA) in our cohort. The significant parameters were analyzed to independently predict OS in a multivariable analysis (MVA) and to create a prognostic model, which was subsequently validated in an independent multi-institutional cohort. Results: We identified 889 patients with active WM at MCR, with a median follow-up of 8.2 [95% confidence interval (CI): 7.5-9] years. The estimated median OS for this cohort was 10.6 (95%CI: 9.7-11.4) years. Patients with available data in this cohort for the validation of rIPSS-WM (n=241) were risk stratified into very low (n=46), low (n=64), intermediate (n=58), high (n=46) and very-high risk groups (n=27) per rIPSS-WM, with the respective 5-year OS rates of 96%, 76%, 72%, 77% and 32%, demonstrating overlapping survival curves for the low, intermediate and the high-risk groups. Because rIPSS-WM could not be validated, we used the data from the MCR cohort and identified age at diagnosis of active WM, LDH >upper limit of normal (ULN), β2M >3µg/mL and albumin <3.5g/dL as statistically significant prognostic markers for OS on UVA. Notably, the presence of MYD88 L265P did not impact OS [median 11.4 years (95%CI: 10.1-not reached (NR) for MYD88 L265P genotype (n=231) versus 10 years (95% CI: 8.1-NR) for MYD88 WT genotype (n=65); p=0.33]. On MVA, LDH >ULN (HR 2.34), serum albumin <3.5 g/dL (HR 1.5) and age groups 65-75 years (HR 1.4) and >75 years (HR 2.6) were independently prognostic. Based on comparable HRs, we assigned a score of 1 point each to serum albumin <3.5 g/dL and age group 66-75 years and similarly, 2 points each for age >75 years and serum LDH >ULN per their impact on OS. Patients with the composite scores of 0, 1 and 2 were categorized as low risk, low- intermediate risk and intermediate risk, respectively. Due to similar OS for the scores of 3 to 5, these were combined to form the high-risk group of our proposed model: Modified Staging System for WM (MSS-WM). The median OS was 14.6 years [95%CI: 9.1 years-NR] for low-risk (score 0, n=71, 21%), 11.2 years (95% CI: 9.1-15.2 years) for low-intermediate risk (score 1, n=110, 32%), 8.1 years (95% CI: 6.4-12.2) for intermediate risk (score 2, n=81, 24%) and 5.5 years (95 % CI: 3.9-11 years) for the high-risk group (score ≥3, n=79, 23%); p<0.0001. In this derivation cohort, the 5-year OS rate was 93%, 82%, 69% and 55% and 10-year OS rate was 60%, 53%, 45% and 30% for the low, low-intermediate, intermediate, and high-risk cohort, respectively ( Figure 1A). We also validated MSS-WM using competing risk analysis (p=0.001) and in the cohort of rituximab treated patients (p<0.0001). We then used data from an independent series of 335 treatment-naïve symptomatic patients from academic institutions (n=5) across the US and Europe for external validation of the MSS-WM model. The median follow-up for the validation cohort was 6.3 years (95% CI: 5.5-7.2 years). The 5-year OS was 93%, 90%, 75% and 57% and the estimated 10-year OS was 91%, 80%, 64% and 35% for the low risk (n= 86, 26%), low-intermediate (n=107, 32%), intermediate (n=86, 26%) and high-risk (n=59, 18%) cohorts, respectively (p<0.0001, Figure 1B). Conclusions: Our proposed model, MSS-WM, is a simple, clinically useful, externally validated model that reliably risk stratifies previously untreated patients with active WM into four groups that have distinct outcomes based on the composite scores derived from the patients' age, serum albumin and serum LDH at diagnosis.
Healthcare Utilization Outcomes of Outpatient CAR-T Cell Therapy with Remote Patient Monitoring Program

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 5075-5075

10.1182/blood-2023-187834

Introduction While chimeric antigen receptor (CAR)-T cell therapy has transformed the management of hematologic malignancies, it requires frequent monitoring for acute toxicities, almost universally achieved through mandatory hospitalizations, therefore utilizing a significant amount of healthcare resources. At Mayo Clinic in Rochester, MN, our standard practice is administering CAR-T cell therapy in the outpatient setting through a multi-disciplinary hospital-based outpatient (HBO) unit and remote patient monitoring (RPM) program. Our CAR-T RPM program consists of in-home, electronic health record-integrated technology to monitor vital signs and neurologic symptoms for 30 days post CAR-T infusion. Here we report the healthcare utilization outcomes of CAR-T patients managed in the outpatient setting enrolled in the RPM program. Methods Patients undergoing FDA-approved CAR-T cell treatment in the outpatient setting and participating in the CAR-T RPM program at Mayo Clinic Rochester were included in this IRB-approved study. Patient characteristics, healthcare utilization metrics, inpatient interventions, and patient satisfaction data regarding the RPM program were reviewed. Length of stay (LOS) includes any hospitalizations for which the admission date falls within the RPM monitoring period (CAR-T cell infusion to day +30), even if the hospitalization continued past day +30. Results A total of 123 patients participated in the CAR-T RPM program and underwent treatment in the outpatient setting. Median age at CAR-T infusion was 63 years (range 22 - 83), and most patients were male (n=78, 63%). Non-Hodgkin lymphoma was the most common diagnosis (n=74, 60%), followed by multiple myeloma (n=47, 38%), ALL (n=1, 1%) and other (n=1, 1%). During the PRM monitoring period, 19 (16%) patients were managed entirely in the outpatient setting. The remaining 104 (84%) patients required at least one hospitalization, with most patients (n=70, 57%) hospitalized only once [26 (21%) patients were hospitalized twice, and 7 (6%) patients were hospitalized 3 times, and 1 (1%) patient hospitalized 4 times during the monitoring period]. When considering the first hospitalization post CAR-T infusion, the median LOS was 6 days (range 2 - 47). When considering all hospitalizations post CAR-T, the median LOS was 8 days (range 2 - 47). Only 7 (6%) patients required an ICU stay, with a mean ICU stay of 0.2 days (standard deviation 0.9). Cytokine release syndrome (CRS) was noted in 92 (75%) of patients at a median of 3 days (range 0 - 18) post CAR-T infusion. All patients with CRS received tocilizumab, at a median of 4 days post CAR-T infusion. Steroids for CRS were administered in 63 (68%) of these patients. Neurotoxicity was reported in 45 (37%) patients at a median of 7 days (range 1 - 19) post CAR-T infusion. During the RPM monitoring period, patients were seen in our HBO unit with a median of 18 outpatient visits (range 4 - 30). Patient survey data, obtained at the end of the RPM monitoring period, were available from 37 patients. The majority of patients felt that the RPM program helped them feel comfortable managing their health at home, were able to reach a team member, and receive an appropriate response promptly. The majority of patients felt comfortable using the RPM equipment and interacting with providers virtually. Overall, 83% of patients were satisfied with the RPM program and 6% were neither satisfied nor dissatisfied. When asked about the reason for disappointment, technical difficulties/issues with the devices were the themes mentioned by the few patients (11%) who were unsatisfied with the RPM program. Conclusion: Despite the complexities and frequent monitoring associated with CAR-T cell therapy, outpatient CAR-T cell treatment is a feasible model of care. As the standard practice at our institution, the CAR-T RPM program was part of the management of nearly all patients undergoing an FDA-approved CAR-T product in the outpatient setting. RPM in the acute setting post CAR-T infusion is a well-received practice initiative by the majority of patients, including a high level of comfort utilizing the RPM equipment and virtual interaction with the RPM providers.
Genome-Wide DNA Methylation Analysis Reveals Epigenetic Influence on Intracellular and Cytokine Signaling Pathways in Waldenström Macroglobulinemia Compared to IgM-MGUS

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 1622-1622

10.1182/blood-2023-182874

Introduction: Waldenström macroglobulinemia (WM) is a rare B-cell lymphoma that may be preceded by an asymptomatic IgM-monoclonal gammopathy of undetermined significance (MGUS). The mechanisms underlying the progression from IgM-MGUS to WM remain to be fully elucidated; however, the stepwise accumulation of genomic abnormalities has been suggested as a potential driver. Currently, the role of epigenetic regulation of DNA remains underexplored in this disease spectrum. Aberrant DNA methylation is a hallmark of oncogenesis that plays an important role in hematologic malignancies. The aim of this study was to assess differential DNA methylation in WM compared to IgM-MGUS and identify hyper- and hypomethylated pathways that may alter key cellular functions. Methods: This study included 15 patients with WM and 6 with IgM-MGUS. Bone marrow samples were prospectively collected and CD19+ and/or CD138+ B cells were positively selected. Subsequently, genome-wide DNA methylation analysis was performed. CpG methylation ratios were segmented into 200-bp regions and differentially methylated regions (DMRs) comparing WM to IgM-MGUS were identified. DMRs with a Q-value <0.05 and absolute methylation difference of ≥20% were considered significant and utilized for analysis. DMRs were annotated according to genomic regions of interest (promotors, 3'UTR, 5'UTR, introns, exons, CpG islands, CpG shores). Next, genes with significant promotor hyper- or hypomethylation were assessed using the Ingenuity Pathway Analysis. Pathways with a corrected p-value<0.05 were considered statistically significant and a Z-value was calculated based on the degree of differential methylation. Results: Genome-wide DNA methylation analysis revealed a significant number of DMRs (n= 15691, hyper: 8248; hypo: 7443) in WM compared to IgM-MGUS. Assessing genomic regions, promotors (hyper: 1379; hypo: 2403), introns (hyper: 1548; hypo: 2292), CpG shores (hyper: 587; hypo: 849) and 3'UTR (hyper: 66; hypo: 193) regions were observed to have a significantly greater number of hypomethylated DMRs (all comparisons, p<0.001) in WM compared to IgM-MGUS (Figure A). While exons (hyper: 1686; hypo: 1378), CpG islands (hyper: 2128; hypo: 82), and 5'UTR (hyper: 854; hypo: 246) regions had a significantly greater number of hypermethylated DMRs (all comparisons, p<0.001) (Figure A). Next, promotor methylation-based pathway analysis revealed differential methylation of multiple cellular pathways important in WM pathogenesis (Figure B). These included pathways involved in intracellular signaling and the regulation of cellular proliferation, such as the STAT3 and CXCR4 pathways which were hypomethylated, and the PTEN signaling pathway which was hypermethylated. Of interest, we have previously demonstrated the transcription factor, STAT3, to have an increased expression in WM and to be implicated in IgM secretion (Elsawa, 2011). Next, multiple cytokine signaling pathways were observed to be hypomethylated in WM compared to IgM-MGUS including members of the interleukin (IL) family (IL-1, IL-8, IL-15, IL-23), VEGF, and TGF-β. Of relevance, previous studies have demonstrated the elevation of IL-8, IL-15, and increased expression of angiogenic cytokines, including VEGF, in patients with WM (Lewicki, 2010; Anagnostopoulos, 2007). Furthermore, our group has also shown miRNA-based epigenetic regulation of IL-8 and IL-15 in WM compared to IgM-MGUS (Chohan, 2023). Lastly, several pathways critical in the regulation of the cell structure and the extracellular matrix (ECM) were found to be hypomethylated including the FGF, actin cytoskeleton, PAK, and FAK signaling pathways. Of note, the FGF/FGFR axis has been demonstrated to be dysregulated in WM, and its targeting has been shown to halt WM cell growth (Sacco, 2021). Conclusions: This study demonstrates differential DNA methylation of key genomic regions in WM compared to IgM-MGUS. Promotor methylation-based analysis reveals hypomethylation of several important cellular pathways involved in cytokine signaling, cell structure/ECM, and intracellular signaling. These results underscore the influence of epigenetics in the IgM-gammopathy disease spectrum and suggest the potential role of aberrant DNA methylation underlying the malignant progression from IgM-MGUS to WM.
Outpatient Management of CAR-T and Teclistamab for Patients with Lymphoma and Multiple Myeloma

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 253-253

10.1182/blood-2023-187186

Background: Patients (pts) receiving FDA-approved chimeric antigen receptor T-cell (CAR-T) therapy or Bispecific antibody Teclistamab (Tec) are commonly managed in the inpatient setting given the common adverse events such as cytokine release syndrome (CRS) and immune cell-associated neurotoxicity syndrome ICANS. We have previously reported that hospital-based outpatient (HBO) management of pts receiving CAR-T is feasible and safe (Bansal et al, ASH2022). In 2023, HBO management at our institution began incorporating home health visits and management of grade 1 CRS in outpatient setting for select pts receiving standard of care (SOC) CAR-T. Here, we report outcomes of our updated practice. Methods: We retrospectively analyzed medical records and remote monitoring data of adult pts who received SOC CAR-T or Tec between 10/2020 and 7/2023 at Mayo Clinic, Rochester under an IRB approved protocol. Results: In 3/2023, pts deemed to be low risk for severe CRS (fever onset >= 3 days from infusion, CRP<100) received HBO management for grade 1 CRS, including outpatient administration of tocilizumab. If CRS improved or resolved, outpatient monitoring was continued. If CRS persisted within the observation period on HBO, pts were admitted. Recurrent CRS after the first episode were all managed inpatient. Nine pts met these criteria for HBO CRS management and their outcomes were compared to those who received initial inpatient (INPT) CRS management (INPT, n=17) during the same timeframe, as well as the outcome of 164 pts who had CRS management INPT prior to our practice change (Table 1). Two-third of the pts with initial management of CRS outpatient did not require hospitalization. Median time to hospitalization trended later than those managed inpatient at the onset of CRS. The duration of hospitalization was comparable for all pts admitted between initial HBO and INPT CRS management. However with fewer admissions in the initial CRS HBO group, the average hospitalization days (LOS) per patient treated for that group was lower compared to initial INPT CRS management. Data on additional pts will be presented at ASH. In 1/2023, pts on RPM with no ongoing CRS symptoms, no language barriers, and no compliance concerns received home health visits during weeks 3 and 4 post CAR-T infusion in place of clinic visits on HBO. Home health visit team communicated with HBO staff to review assessment and plan. Changes in HBO utilization will be presented. Finally, 24 pts received 223 Tec infusions on HBO. Median age was 66 years, 15 (61%) were males, 9 (38%) had high risk cytogenetics. The median prior lines of therapy was 5. Among these pts, 220/223 (99%) doses were performed on HBO and 204/220 (93%) infusions never required admission for management. Twenty pts enrolled in RPM (Figure 1). An average of 2 alerts were generated per patient during the 2 week period and median time from infusion to alert was 1.5 days. Majority of alerts were resolved over a phone call and only 13/114 (11%) alerts required a physician visit/hospital admission. Of the 16 Tec infusions resulting in admission, 4/16 (25%) required re-admission resulting in a total of 20 hospitalizations. Admissions mostly occurred during step-up dosing (18/20; 90%). Most common reason for first admission was fever (13/16, 85%) and median time to admission was 1 day from infusion. Median LOS was 1.5 days (range, 0-12). In terms of CRS, majority were Grade 1 (12/13, 93%) which were managed with steroids (dexamethasone/ prednisone) alone. One patient had CRS grade 4 event, in the setting of concurrent decompensation during dialysis, and was treated with steroids, tocilizumab, vasopressor, CRRT, thoracentesis, intubation and mechanical ventilation. The rate of second CRS event after management of first CRS with steroid (dexamethasone/ prednisone) was 15% (2/13). These second CRS episodes also resolved with steroid alone. Data on additional pts receiving Tec will be presented at ASH. Conclusion: Our data showed that additional advances in outpatient practice, including initial outpatient management of CRS and outpatient administration of Tec step up dosing are feasible, safe and reduce hospital resource utilization.
Hepatic Response and Progression Criteria in Light Chain Amyloidosis: A Multicenter Validation Study

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 3411-3411

10.1182/blood-2023-190226

Background: Liver involvement in light chain amyloidosis (AL) is seen in up to 20% of patients and is typically encountered as part of multi-organ involvement. Liver involvement is associated with a poor prognosis. The goal of this study was to assess the prognostic impact of the hepatic response criteria, which were published in 2005 and were not broadly assessed for their prognostic value. Patients and methods: Ten centers across the USA and Europe participated in this study.AL amyloidosis patients who were diagnosed between 2010 and 2015, had liver involvement with serum alkaline phosphatase (AP) >1.5 upper reference limit (URL), and achieved hematologic response to therapy were included in this study. Hepatic response was assessed at 6, 12, and 24 months from therapy initiation and at best response. Based on a receiver operation characteristic analysis, a 50% reduction in AP was set as the optimal cut point for discrimination of 5-year overall survival (OS) in the 12-months response assessment landmark (area under the curve 0.67). Therefore, hepatic response was defined as a reduction in AP >50% from baseline value in addition to AP normalization, regardless of AP percentage reduction. Hepatic progression was defined as >50% increase in serum AP. OS was assessed from therapy initiation until death or last follow-up and was plotted using the Kaplan-Meier method. The log-rank test used to compare survival between groups. For fixed-time point survival analysis, patients who died before the landmark were excluded. Hepatic response at a fixed time points, when missing, was imputed based on available data from adjacent time points (imputation of hepatic response was performed in 15%, 23%, and 22% of evaluable patients at 6-, 12-, and 24-month landmarks, respectively). Multivariate Cox proportional models were set to determine independent prognostic factors for OS using variables with p-value <0.1 in a univariate analysis. P-values <0.05 were considered significant. Results: One hundred and sixteen patients (n=116) are included. The median age was 60 years, and the median serum AP was X2.6 URL. Concomitant kidney involvement was present in 63.8% of patients, while coexisting heart involvement was seen in 56% of patients. Hematologic VGPR or better was achieved in 69% of patients. AP decrease deepened with time, with a median reduction at 6-, 12-, 24-months and best response being 22%, 34%, 53%, and 56%, respectively. Overall, 65% of patients (n=75) achieved hepatic response, of whom 71 patients based on reduction in AP >50% and 4 patients for reaching AP within normal reference but not meeting >50% reduction in AP (40- 46% reduction in AP). The median time to hepatic response was 13.8 months, longer for patients undergoing autologous stem cell transplantation (ASCT) as their primary therapy compared to non-transplant therapies (24 vs 12.6 months, P=0.1). With a median follow-up of 105 months, 42 patients died (36.2% of the study cohort). The 2-, 5- and 10-year OS rates were 83%, 67%, and 61%, respectively. Achievement of hepatic response as early as 12 months and at best response was associated with a longer survival (Figure). Hepatic response was an independent prognostic factor in a multivariate analysis, after adjusting for other known prognostic factors (age, cardiac stage, hematologic response, and primary therapy). Predictors of hepatic response include higher baseline AP level, lower total bilirubin, hematologic ≥VGPR, and cardiac and renal responses, when applicable. Hepatic progression was borderline associated with inferior OS (5-year OS 47% vs 70% among non-progressors, P=0.08). Conclusions: Hepatic response and progression measured by the change in alkaline phosphatase are prognostic in AL amyloidosis. These criteria are independent of other prognostic markers, and thus may have clinical implications for patients' care.
Early Predictors of Severe Cytopenia Post CAR-T for Identification of Patients for Potential Stem Cell Collection

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 6927-6927

10.1182/blood-2023-189683

Background: Cytopenias are a common complication of and prolonged (beyond month 3 post CAR-T infusion), severe (grade 3 or higher) cytopenias can be difficult to manage. Stem cell boosts have been reported to restore hematopoiesis; however, stem cells would need to be available prior to CAR-T therapy for potential use post CAR-T. Most lymphoma patients and limited number of myeloma patients may have pre-collected stem cells in storage. Identifying patients at high risk for prolonged and severe cytopenia post CAR-T at the time of CAR-T evaluation (baseline), before leukapheresis, can help identify the patients for coordination of stem cell collection during CAR-T manufacturing and increase the likelihood that the collected stem cells would be used. In this study, we aim to identify clinical variables at the time of CAR-T evaluation, prior to leukapheresis, that are associated with severe cytopenias at month 3 post CAR-T infusion and identify patients who could be considered for pre-emptive stem cell collection prior to CAR-T therapy. Methods: We conducted a retrospective analysis of patients with multiple myeloma (MM) and non-Hodgkin lymphoma (NHL) who received CAR-T products at Mayo Clinic from 01/2016 to 06/2022. Patients with progressive disease in the first year post CAR-T were excluded from the analysis. Baseline (at CAR-T evaluation, prior to leukapheresis) variables were compared between those with and without severe cytopenia at month 3 post CAR-T. Severe cytopenias were defined as hemoglobin (Hg) < 8 g/dL, absolute neutrophil count (ANC) < 0.5 x 10 9/L, and/or platelet count (PLT) < 50 x 10 9/L. Statistically significant variables (p<0.05) by analysis were examined for statistical significance in multivariate analysis (MVA). Results: Among the 166 patients who received CAR-T (88 NHL, 78 MM) during the study period, 31 (18.67%) had a severe cytopenia at month . Twenty baseline variables were examined; HGB, PLT, ANC, and c-reactive protein (CRP) We devised a cytopenia risk score using 1 point each for Hg<10 or PLT<100k at baseline, with a range of 0 to 2. Demographics and clinical outcome by cytopenia risk score is shown in Table 1B. A higher percentage of patients with a score of 1 or 2 had a severe cytopenia at month 3 (Figure 1). In particular, there was a . In addition Conclusion: Baseline cytopenias before leukapheresis may identify patients with increased risk for severe cytopenias at month 3 post CAR-T. These patients can have continued slow hematopoietic recovery in the first year. Stem cell collection, if feasible, could be considered before CAR-T to alleviate post-CAR-T severe prolonged cytopenias.
Pooled Analysis of Safety from Birtamimab Phase 1-3 Studies in Patients with Light Chain (AL) Amyloidosis

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 3409-3409

10.1182/blood-2023-174703

Introduction: SystemicAL amyloidosis is a progressive and often fatal disease caused by misfolded light chains that aggregate into amyloid fibrils and deposit in vital organs, leading to organ dysfunction. Current standard of care (SoC) therapies for AL amyloidosis target the plasma cell clone to reduce or eliminate light chain production, but do not remove soluble toxic light chain aggregates or insoluble amyloid deposits. Early mortality remains high for patients with advanced disease (e.g., Mayo 2012 Stage IV disease, median overall survival <6 months). Birtamimab - a humanized monoclonal antibody that neutralizes soluble, toxic light chain aggregates and depletes insoluble amyloid deposits by inducing phagocytosis - is under investigation for the treatment of AL amyloidosis. Here, we present a pooled safety analysis from previous Phase 1-3 clinical trials, with a focus on the 2 double-blind randomized controlled trials (RCTs): PRONTO (NCT02632786) and VITAL (NCT02312206). Methods: Patients with AL amyloidosis were treated with intravenous birtamimab up to 24 mg/kg every 28 daysin the non-placebo-controlled Phase 1/2 open-label trial (NCT01707264) with open-label extension (OLE; NCT02613182) and 2 RCTs (Phase 2 PRONTO with OLE [NCT03154047] and Phase 3 VITAL). In PRONTO, patients had received ≥1 previous systemic therapy with at least a partial hematologic response and persistent cardiac dysfunction, and received birtamimab or placebo. In VITAL, newly diagnosed treatment-naïve patients with cardiac involvement received birtamimab + SoC or placebo + SoC (where SoC was a bortezomib-containing chemotherapy regimen). The analysis included all patients who received ≥1 dose of birtamimab. Pooled median exposure times were calculated, and baseline characteristics and demographics were summarized. For VITAL and PRONTO, pooled rates and severity of treatment-emergent adverse events (TEAEs) with birtamimab were compared with rates in the placebo arms. In addition, safety data from the non-placebo-controlled studies were summarized. Results: The median (range) exposure to birtamimab among 302 patients pooled from the Phase 1-3 trials was 12.24 (0.03-57.72) months. Of the 302 patients exposed to birtamimab, 295 received at least one 24-mg/kg infusion, up to 2500 mg. Analysis of the 2 randomized, placebo-controlled trials included data from 196 patients treated with birtamimab from the PRONTO (n=66) and VITAL (n=130) trials and 193 patients who received placebo (PRONTO, n=63; VITAL, n=130). Both trials had comparable treatment durations overall. The rates of TEAEs, serious and grade ≥3 TEAEs were similar between birtamimab and placebo arms within each trial and between treatment arms in the placebo-controlled pooled analysis set (PRONTO and VITAL; Table 1). Higher rates of treatment-related, serious, and grade ≥3 TEAEs were reported in VITAL compared with PRONTO, presumably due to the treatment-naïve population and receipt of concomitant SoC therapy in VITAL. In the pooled analysis set, the most common TEAEs that occurred with greater frequency in the birtamimab vs placebo arms in either trial were, respectively, fatigue (36.2%, 34.2%), diarrhea (33.2%, 33.7%), nausea (31.6%, 30.1%), constipation (31.1%, 31.6%), and dyspnea (25.0%, 24.9%). The most commonly reported (≥5%) serious and grade ≥3 TEAEs were primarily cardiac disorders (cardiac failure, syncope, cardiac arrest), consistent with the underlying disease. Infusion-associated TEAE rates were low in the pooled birtamimab and placebo arms (5.1% vs 3.6%, respectively) and were generally mild to moderate. The safety profile observed in the non-placebo-controlled Phase 1/2 trial plus OLE and PRONTO OLE (n=106) was consistent with the safety data reported in the placebo-controlled studies. Conclusions: Birtamimab was well tolerated in patients with AL amyloidosis when administered as monotherapy and did not demonstrate additive toxicity when given with SoC chemotherapy. Rates of TEAEs in the birtamimab arm were similar to rates in the placebo arm in the PRONTO and VITAL trials. The safety and efficacy of birtamimab is being further investigated in an ongoing confirmatory Phase 3 double-blind RCT in patients with Mayo Stage IV AL amyloidosis (AFFIRM-AL; NCT04973137), which is currently enrolling.
Cumulative Deficits Frailty Index and Relationship Status Predict Survival in Patients with Multiple Myeloma

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 1986-1986

10.1182/blood-2023-187845

Background: Frailty is a state of decreased reserve affecting multiple organ systems, thereby increasing vulnerability to stressors. Several tools have been proposed to measure frailty in multiple myeloma (MM), such as the IMWG frailty index, and the Revised Myeloma Comorbidity Index. However, these are based on clinical trial datasets, and include chronological age as one of the indicators of frailty. A frailty index based on the principle of accumulation of health deficits (Rockwood doi:10.1093/gerona/62.7.738), provides a measure of physiologic age. This index can be readily calculated using various combinations of health deficits and has been shown to predict outcomes in several populations. Social support has been associated with improved outcomes in various populations, however its impact on survival in patients with MM has not been well studied. The objective of this study was to assess the impact of frailty measured by a deficit accumulation frailty index and the impact of relationship status on outcomes in patients with newly diagnosed MM. Methods: This is a retrospective study including patients diagnosed with MM between January 6 th, 2005, and September 19 th, 2018. We calculated a deficit accumulation frailty index using previously published methods (McNallan et. al doi.org/10.1016/j.ahj.2013.07.008, Searle et al. doi.org/10.1186/1471-2318-8-24). We used the electronic medical record system at Mayo Clinic in Rochester, MN, to extract data on activities of daily living (14 items) provided by patient-completed questionnaires, and data on comorbidities as recorded by treating providers (16 items), within 6 months prior to diagnosis. Each item was scored as 0, 0.5, or 1, with 1 indicating the presence of deficit (Table 1). The frailty index was defined as the sum of individual scores divided that by the total number of non-missing items. Patients who had N >2 missing items were excluded. Patients with a frailty index ≥0.15 were considered frail. We also extracted data on self-reported relationship status within 6 months prior to diagnosis. Variables were compared between groups using Fisher's exact test and Wilcoxon signed-rank test for categorical and continuous variables, respectively. Univariate and multivariate analysis were performed using Cox proportional hazard models. Overall survival (OS) was estimated using the Kaplan-Meier method and compared between groups using the Log-rank test. P values <0.05 were considered statistically significant. Results: We included 578 patients. Median age was 67 (interquartile range: 59-74) years, and 40% were female. Among all patients, 226 (39%) were frail. Compared to fit patients, patients who were frail were older (median age: 70 vs. 65 years, P<0.001) and more likely to have International Staging System (ISS) III (vs. I/II) disease (47% vs. 27%, P<0.001) and ECOG performance status ≥2 (vs. 0 or 1) (45% vs. 17%, P<0.001). There was no difference in R-ISS III disease or presence of high-risk cytogenetic abnormalities between fit and frail patients. Median OS was 7.6 and 4.1 years in fit and frail patient, respectively (P<0.001). Physician assessed ECOG performance status was available for 268 patients. Among patients with ECOG performance status 0 or 1 (193 patients), 136 (70%) were fit, and 57 (30%) were frail. The OS was 8.3 and 4.6 years in the 2 groups, respectively (P=0.006) (table 2). On multivariate analysis including age, frailty status, and R-ISS stage (III vs. I/II), all were associated with OS with frailty's hazard ratio (HR): 1.4 (95%CI [1.1-1.8]), P=0.004; the HR was 1.4 (95%CI [1.1-1.9]), P=0.02, when analysis was restricted to patients ≥60 years. Among all patients, those who were married or in a committed relationship (474 patients) had improved survival (median OS: 7.0 vs. 3.7 years, respectively, P<0.001) compared to patients who were divorced/separated, widowed, or single (96 patients). On multivariate analysis, which included age, R-ISS III, frailty status, and relationship status, all were associated with OS. The HR for relationship status was 1.4 (95%CI [1.0-1.8]), P=0.0465. Conclusion: Frailty, defined by the deficit accumulation frailty index, is independently associated with decreased survival in patients with newly diagnosed MM. Being married or in a committed relationship is associated with improved survival independent of age, disease stage, and frailty.