D'Souza, Anita

ABSTRACT Systemic AL amyloidosis is a clonal plasma cell dyscrasia, where toxic free light chains (FLCs) lead to vital organ damage, with risk of early mortality despite effective therapies. Notably, there is a paucity of data on the incidence and predictors of early mortality in the daratumumab (Dara) era. We conducted a multi‐center retrospective cohort study to develop and validate a risk‐prediction model for early mortality (all‐cause death within 6 months) in patients treated with Dara‐based frontline regimens. We used univariate analysis to identify covariates for a logistic regression model predictive of 6‐month mortality and generated a clinical risk score. Among 339 patients across eight centers, 36 (10.6%) experienced early mortality. Multivariate analysis identified four independent predictors: NT‐proBN P > 5300 pg/mL (odds ratio [OR] 3.83, p = 0.006), A ge > 75 years (OR 2.96, p = 0.073), absence of t(11;14) on C ytogenetics (OR 3.0, p = 0.022), and E COG performance status (OR 1.72 per unit increase, p = 0.044). The resulting PACE score stratified patients into three risk groups with a 6‐month mortality of 1.2% (low‐risk), 11.7% (intermediate‐risk), and 50.0% (high‐risk). The PACE score demonstrated superior discrimination (C‐index 0.78) for early mortality compared to Mayo 2004 (0.69) and Mayo 2012 (0.55) staging systems. External validation confirmed robust discrimination (C‐index 0.73) with corresponding 6‐month mortality rates of 4.2%, 15.25%, and 37.04% across respective risk groups. The PACE score provides a clinically applicable tool for early mortality risk stratification in AL amyloidosis patients receiving Dara‐based therapy, and will enable improved patient counseling, clinical trial design, and identification of ultra‐high‐risk patients requiring intensive monitoring and novel therapies.

Abstract Patients with multiple myeloma have an elevated risk of severe complications from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; COVID-19) infection. To demonstrate proof of concept for a pandemic preparedness and response network, the American Society of Hematology Research Collaborative Multiple Myeloma Program developed a prospective, decentralized study within a site-based provider network. In the COVID-19 outcomes in myeloma and the impact of vaccines (COSMIC) study, patients provided consent, permitted electronic health record data collection, completed patient-reported outcomes at baseline, day 30, and day 180 through an electronic study portal, and were compensated for participation. Clinicians at participating sites facilitated study recruitment and shared best practices monthly to accelerate study execution. The COSMIC study rapidly consented 201 patients from 8 participating sites over 4 months (22 January 2024 through 17 May 2024). Consented participants were 30 to 93 years old, with a median age of 67; 46% were female, 69% were non-Hispanic White, 17% were non-Hispanic Black, and 8% were Hispanic/Latino. Patient-reported data completion was 97% at baseline, 81% at 1 month, and 79% at 6 months. At baseline, 55% of patients reported a history of COVID-19 infection and had received a median of 4 SARS-CoV-2 vaccines. For all patients, there were an additional 18 COVID-19 infections and 57 vaccines received during the 6-month observation period. There were no significant differences in health-related quality of life over time or by history of COVID-19 infection. COSMIC demonstrates the feasibility of an innovative evidence generation strategy to drive rapid accrual of patients to address an evolving area of need. This trial was registered at www.clinicaltrials.gov as #NCT05831787.

Abstract Consumption of a Western diet and high body mass index (BMI) are risk factors for progression from premalignant phenotypes to multiple myeloma, a hematologic cancer. In the NUTRIVENTION trial (NCT04920084), we administered a high-fiber, plant-based diet (HFPBD; meals for 12 weeks, coaching for 24 weeks) to 23 participants with myeloma precursor states and elevated BMI. The intervention was feasible and improved quality of life and modifiable risk factors: metabolic (BMI, insulin resistance), microbiome (diversity, composition), and immune (inflammation, monocyte subsets). Disease progression trajectory improved (n = 2) or was stable. Findings were translated to Vk*MYC mice modeling the myeloma precursor state, in which a high-fiber diet (HFD) delayed disease progression through improved metabolism and microbiome composition, leading to increased short-chain fatty acid production that reinvigorated antitumor immunity and inhibited tumor growth. These effects from fiber consumption were independent of calorie restriction and weight loss. A HFD is a low-risk intervention that may delay progression to myeloma. Significance: A HFPBD in participants with precursor plasma cell disorders and an elevated BMI improved metabolic, microbiome, and immune biomarkers of disease. In a subset, it may delay progression to myeloma. In mouse models, a HFD delayed progression to myeloma independent of calorie restriction. See related commentary by Fairfield and Reagan, p. 623

Summary Chimeric antigen receptor T‐cell (CAR‐T) therapy and bispecific T‐cell engagers (BsAb) have emerged as promising immunotherapeutic modalities in patients with relapsed and/or refractory multiple myeloma (RRMM). However, there is limited data on the safety and efficacy of CAR‐T and BsAb therapies in MM patients with a prior history of allogeneic transplantation (allo‐HCT). Thirty‐three MM patients with prior allo‐HCT received CAR‐T ( n = 24) or BsAb ( n = 9) therapy. CAR‐T therapy demonstrated an ORR of 92% (67% ≥ CR), and 73% were MRD negative. BsAb therapy resulted in an ORR of 44% (44% ≥ CR) and 44% MRD negative. Safety analysis showed grade ≥3 AEs in 92% of CAR‐T and 56% of BsAb patients. Cytokine release syndrome (CRS) occurred in 83% of CAR‐T and 78% of BsAb recipients, while immune effector cell‐associated neurotoxicity syndrome (ICANS) was observed in three CAR‐T patients. Infections of grade ≥3 were reported in 50% of CAR‐T and 44% of BsAb recipients. No exacerbation of graft‐versus‐host disease occurred except in one BsAb recipient. CAR‐T and BsAb therapies appear to be feasible, safe and provide deep and durable responses in MM patients with prior allo‐HCT.

AbstractBackgroundLenalidomide maintenance after autologous stem cell transplant (ASCT) in multiple myeloma (MM) results in superior progression‐free survival and overall survival. However, patients with high‐risk multiple myeloma (HRMM) do not derive the same survival benefit from lenalidomide maintenance compared with standard‐risk patients. The authors sought to determine the outcomes of bortezomib‐based maintenance compared with lenalidomide maintenance in patients with HRMM undergoing ASCT.MethodsIn total, the authors identified 503 patients with HRMM who were undergoing ASCT within 12 months of diagnosis from January 2013 to December 2018 after receiving triplet novel‐agent induction in the Center for International Blood and Marrow Transplant Research database. HRMM was defined as deletion 17p, t(14;16), t(4;14), t(14;20), or chromosome 1q gain.ResultsThree hundred fifty‐seven patients (67%) received lenalidomide alone, and 146 (33%) received bortezomib‐based maintenance (with bortezomib alone in 58%). Patients in the bortezomib‐based maintenance group were more likely to harbor two or more high‐risk abnormalities and International Staging System stage III disease (30% vs. 22%; p = .01) compared with the lenalidomide group (24% vs. 15%; p < .01). Patients who were receiving lenalidomide maintenance had superior progression‐free survival at 2 years compared with those who were receiving either bortezomib monotherapy or combination therapy (75% vs. 63%; p = .009). Overall survival at 2 years was also superior in the lenalidomide group (93% vs. 84%; p = .001).ConclusionsNo superior outcomes were observed in patients with HRMM who received bortezomib monotherapy or (to a lesser extent) in those who received bortezomib in combination as maintenance compared with lenalidomide alone. Until prospective data from randomized clinical trials are available, post‐transplant therapy should be tailored to each patient with consideration for treating patients in clinical trials that target novel therapeutic strategies for HRMM, and lenalidomide should remain a cornerstone of treatment.

Abstract The overall survival (OS) has improved significantly in multiple myeloma (MM) over the last decade with the use of proteasome inhibitor and immunomodulatory drug-based combinations, followed by high-dose melphalan and autologous hematopoietic stem cell transplantation (auto-HSCT) and subsequent maintenance therapies in eligible newly diagnosed patients. However, clinical trials using auto-HSCT followed by lenalidomide maintenance have shown an increased risk of second primary malignancies (SPM), including second hematological malignancies (SHM). We evaluated the impact of SPM and SHM on progression-free survival (PFS) and OS in patients with MM after auto-HSCT using CIBMTR registry data. Adult patients with MM who underwent first auto-HSCT in the United States with melphalan conditioning regimen from 2011 to 2018 and received maintenance therapy were included (n = 3948). At a median follow-up of 37 months, 175 (4%) patients developed SPM, including 112 (64%) solid, 36 (20%) myeloid, 24 (14%) SHM, not otherwise specified, and 3 (2%) lymphoid malignancies. Multivariate analysis demonstrated that SPM and SHM were associated with an inferior PFS (hazard ratio [HR] 2.62, P &lt; .001 and HR 5.01, P &lt; .001, respectively) and OS (HR 3.85, P &lt; .001 and HR 8.13, P &lt; .001, respectively). In patients who developed SPM and SHM, MM remained the most frequent primary cause of death (42% vs 30% and 53% vs 18%, respectively). We conclude the development of SPM and SHM leads to a poor survival in patients with MM and is an important survivorship challenge. Given the median survival for MM continues to improve, continued vigilance is needed to assess the risks of SPM and SHM with maintenance therapy post–auto-HSCT.

PURPOSE ABBV-383, a B-cell maturation antigen × CD3 T-cell engaging bispecific antibody, has demonstrated promising results in an ongoing first-in-human phase I study (ClinicalTrials.gov identifier: NCT03933735 ) in patients with relapsed/refractory multiple myeloma (RRMM). Herein, we report safety and efficacy outcomes of this phase I dose escalation/expansion study. METHODS Patients with RRMM (≥ three prior lines including a proteasome inhibitor, an immunomodulatory drug, and an anti-CD38 monoclonal antibody) were eligible. ABBV-383 was administered intravenously over 1-2 hours once every 3 weeks, without any step dosing. A 3 + 3 design with backfilling for dose escalation was used (intrapatient escalation to highest safe dose permitted) followed by initiation of dose expansion. RESULTS As of January 8, 2022, 124 patients (dose escalation [0.025-120 mg], n = 73; dose expansion [60 mg], n = 51) have received ABBV-383; median age was 68 years (range, 35-92 years). The most common hematologic treatment-emergent adverse events (TEAEs) were neutropenia (all grades: 37%) and anemia (29%). The most common nonhematologic TEAEs were cytokine release syndrome (57%) and fatigue (30%). Seven deaths from TEAEs were reported with all considered unrelated to study drug by the investigator. For all efficacy-evaluable patients (n = 122; all doses), the objective response rate (ORR) was 57% and very good partial response (VGPR) or better (≥ VGPR) rate was 43%. In the 60 mg dose expansion cohort (n = 49), the ORR and ≥ VGPR rates were 59% and 39%, respectively; and in the ≥ 40 mg dose escalation plus dose expansion cohorts (n = 79) were 68% and 54%, respectively. CONCLUSION ABBV-383 in patients with RRMM was well tolerated with an ORR of 68% at doses ≥ 40 mg. This novel therapy's promising preliminary antitumor activity in heavily pretreated patients warrants further clinical evaluation.