BCMA- or GPRC5D-targeting bispecific antibodies in multiple myeloma: efficacy, safety, and resistance mechanisms.

ABSTRACT: Bispecific antibodies that engage T cells to target B-cell maturation antigen or G-protein-coupled receptor class C group 5 member D have demonstrated remarkable efficacy in heavily pretreated relapsed or refractory multiple myeloma (MM), leading to the recent accelerated approval of teclistamab, elranatamab, and talquetamab by health agencies. Future challenges, however, remain to define their optimal dosing schedule and duration, sequencing, and integration with established anti-MM therapeutics as well as delineating the biological and clinical mediators of immune escape.

Integrated epigenetic and transcriptional single-cell analysis of t(11;14) multiple myeloma and its BCL2 dependency.

ABSTRACT: The translocation t(11;14) occurs in 20% of patients with multiple myeloma (MM) and results in the upregulation of CCND1. Nearly two-thirds of t(11;14) MM cells are BCL2 primed and highly responsive to the oral BCL2 inhibitor venetoclax. Although it is evident that this unique sensitivity to venetoclax depends on the Bcl-2 homology domain 3- proapoptotic protein priming of BCL2, the biology underlying t(11;14) MM dependency on BCL2 is poorly defined. Importantly, the epigenetic regulation of t(11;14) transcriptomes and its impact on gene regulation and clinical response to venetoclax remain elusive. In this study, by integrating assay for transposase-accessible chromatin by sequencing (ATAC-seq) and RNA-seq at the single-cell level in primary MM samples, we have defined the epigenetic regulome and transcriptome associated with t(11;14) MM. A B-cell-like epigenetic signature was enriched in t(11;14) MM, confirming its phylogeny link to B-cell rather than plasma cell biology. Of note, a loss of a B-cell-like epigenetic signature with a gain of canonical plasma cell transcription factors was observed at the time of resistance to venetoclax. In addition, MCL1 and BCL2L1 copy number gains and structural rearrangements were linked to venetoclax resistance in patients with t(11;14) MM. To date, this is the first study in which both single-cell (sc) ATAC-seq and scRNA-seq analysis are integrated into primary MM cells to obtain a deeper resolution of the epigenetic regulome and transcriptome associated with t(11;14) MM biology and venetoclax resistance.

Impact of soluble BCMA and non-T-cell factors on refractoriness to BCMA-targeting T-cell engagers in multiple myeloma.

Adoptive T cell therapy is a promising therapy for multiple myeloma (MM), but its efficacy hinges on understanding relevant biological and predictive markers of response. B cell maturation antigen (BCMA) is a key target antigen in MM, with active development of multiple anti-BCMA T cell engagers (TCE) and chimeric antigen receptor T cell (CAR T) therapies. The regulation of surface BCMA expression by MM cells, resulting in the shedding of soluble BCMA (sBCMA), has triggered debate surrounding the significance of sBCMA as a predictive marker and its potential impact on treatment outcomes. In order to address this, we leveraged whole genome sequencing and in vitro assays to demonstrate that sBCMA may independently predict primary refractoriness to anti-BCMA therapies. In addition to sBCMA, tumor burden and surface BCMA antigen density collectively influence anti-BCMA TCE cytotoxic efficacy. Correlative analyses of 163 patients treated with anti-BCMA TCE teclistamab validated and further underscored the association between elevated baseline sBCMA (>400 ng/mL) and refractoriness. Importantly, increasing TCE dose, the use of TCE against alternative targets (e.g.,GPRC5D), or gamma secretase inhibitors were able to overcome high sBCMA. These findings highlight the importance of accounting for baseline sBCMA levels, disease burden, and TCE dose intensity when administering anti-BCMA TCEs, offering critical insights for optimizing therapeutic strategies to overcome specific high-risk features and primary anti-BCMA TCE refractoriness.

Impact of COVID-19 on the Diagnosis and Management of Multiple Myeloma: Experience from a Canadian Center.

BACKGROUND: The impact of coronavirus disease-19 on the management of multiple myeloma (MM) has been recognized. However, the real effect on clinical outcomes remains poorly understood. OBJECTIVE: We describe a local experience of the management of MM patients and report their outcomes during the current pandemic. METHODS: All consecutive symptomatic MM patients seen at our center since 03/20 were evaluated. RESULTS: A cohort of 156 patients diagnosed from 01/19 to 12/20 was analyzed to interrogate differences in presentation patterns. A total of 553 MM patients were seen and/or treated at Tom Baker Cancer Center in the year of 2020. From those, 47.1% (n = 261) were tested for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Sixteen patients tested positive and data are presented. In addition, a decrease of 21.7% in the rate of new smoldering MM/MM diagnosis was observed in 2020 as compared to 2019. Further, an increase in deaths was also observed in 2020. CONCLUSIONS: Our study confirms an increase lethality for MM patients infected with SARS-CoV-2. A balance between safety and need for cancer control should be emphasized.

N-Terminal pro-brain natriuretic peptide (NTproBNP) in patients with symptomatic multiple myeloma: report from a single institution.

Elevated levels of serum cardiovascular markers including natriuretic peptides (NPs) such as amino terminal pro-brain natriuretic peptide (NTproBNP) have been associated with disease severity and survival in cancer patients and more recently in multiple myeloma (MM). In the present study, we retrospectively reviewed 87 consecutive symptomatic TEMM (transplant-eligible) and 126 TIMM (transplant-ineligible) patients treated at our institution that did undergo NTproBNP testing from 2017 to 2020. Median age at diagnosis was 59.3 years and 75.4 years for the TEMM and TIMM groups, respectively (p = 0.0001). NTproBNP ≥ 300 ng/L was used to assess survival outcomes in the group of symptomatic MM. Patients with AL amyloidosis and symptomatic MM were excluded from the study. Median OS for patients with NTproBNP ≥ 300 ng/L was shorter (45.9 months) as compared to those with NTproBNP of < 300 ng/L (non-reached) (p = 0.0001). In addition, OS was shorter for those with CCI > 2, ISS2-3, and high-risk cytogenetics by FISH and ≥ 70 years of age. Multivariate analysis showed that HR cytogenetics and ISS2-3 were independent predictors for OS in the entire cohort of MM patients. When restricted to TIMM, age ≥ 80 years and NTproBNP ≥ 800 ng/L were predictors for OS in univariate and multivariate analyses. In conclusion, NTproBNP appears to be an independent predictor factor for OS in symptomatic TIMM patients. The use of NTproBNP as a frailty marker remains to be elucidated. However, NTproBNP could potentially be used to guide treatment decisions aimed to minimize cardiovascular and renal toxicity for myeloma therapies that potentially do have cardio-renal implications.

The impact of COVID-19 in the management of AL amyloidosis and Immunoglobulin Deposition Disease: A single-center experience.

INTRODUCTION: Patients with AL amyloidosis and immunoglobulin deposition diseases (IDD) are vulnerable during the COVID-19 pandemic due to the immune compromise from the plasma cell disorder and therapy-related immune defects. We describe a local experience in providing care for patients with AL amyloidosis and IDD. METHOD: Patient treatment and disease status since the beginning of the pandemic on March 11, 2020, as declared by WHO, were collected and analyzed. RESULTS: Ninety-six patients with AL amyloidosis and IDD were included. Four patients with IDD and 22 patients with systemic AL amyloidosis were receiving treatment during the pandemic. Since the pandemic, patients' treatments were discontinued if they achieved VGPR or better postinduction. Seven patients discontinued all treatment after achieving VGPR, and others required treatment modifications. 28 patients have been tested for COVID-19, and all tests have been negative. Three patients died since the pandemic, two from organ complications of systemic AL amyloidosis and one from an unrelated cause. CONCLUSION: The management of AL amyloidosis and IDD must be individualized on the clinical characteristics, centers' access to care under the pandemic restrictions, and the epidemiological aspects of the outbreak.

Monoclonal Gammopathy of Undetermined Significance Clinic during the Coronavirus Disease-19 Pandemic: Caring for the Vulnerable in an Academic Medical Center.

BACKGROUND: Patients with monoclonal gammopathy of undetermined significance (MGUS) have clinical features including older age, presence of medical comorbidities, susceptibility to infections, and thrombotic tendencies which are relevant when assessing their risk during the coronavirus disease (COVID-19) pandemic. OBJECTIVE: To study the vulnerability of patients with MGUS during the COVID-19 pandemic, we assessed the local management of MGUS patients and their clinical outcomes. METHODS: Retrospective chart reviews were performed for all patients with MGUS seen at a university medical center clinic (2014-2020). RESULTS: A total of 228 MGUS patients were included; 211 patients are alive, 7 patients died before the pandemic, and 10 patients died since the pandemic declaration. The mean age and the overall survival (OS) of the patients who died before versus during the pandemic were 83.0 versus 75.2 years, p = 0.4, and OS 40.6 versus 53.2 months, p = 0.3, respectively. One patient died of COVID-19. Nine patients had venous thromboembolisms (VTE), all of which occurred before the pandemic onset. CONCLUSIONS: There were no significant differences found in the mean age or OS of the MGUS patients who died before versus after the pandemic onset. An increase in VTE rates was not seen. Study results are limited by small patient numbers.

Sorption of Perfluoroalkyl Phosphonates and Perfluoroalkyl Phosphinates in Soils.

Perfluoroalkyl phosphonates (PFPAs) and perfluoroalkyl phosphinates (PFPiAs) are recently discovered perfluoroalkyl acids (PFAAs) that have been widely detected in house dust, aquatic biota, surface water, and wastewater environments. The sorption of C6, C8, and C10 monoalkylated PFPAs and C6/C6, C6/C8, and C8/C8 dialkylated PFPiAs was investigated in seven soils of varying geochemical parameters. Mean distribution coefficients, log Kd*, ranged from 0.2 to 2.1 for the PFPAs and PFPiAs and were generally observed to increase with perfluoroalkyl chain length. The log Kd* of PFPiAs calculated here (1.6-2.1) were similar to those previously measured for the longer-chain perfluorodecanesulfonate (1.9, PFDS) and perfluoroundecanoate (1.7, PFUnA) in sediments, but overall when compared as a class, were greater than those for the perfluoroalkanesulfonates (-0.8-1.9, PFSAs), perfluoroalkyl carboxylates (-0.4-1.7, PFCAs), and PFPAs (0.2-1.5). No single soil-specific parameter, such as pH and organic carbon content, was observed to control the sorption of PFPAs and PFPiAs, the lack of which may be attributed to competing interferences in the naturally heterogeneous soils. The PFPAs were observed to desorb to a greater extent and likely circulate as aqueous contaminants in the environment, while the more sorptive PFPiAs would be preferentially retained by environmental solid phases.

Sustainability of a proactive geriatric trauma consultation service.

BACKGROUND: Proactive geriatric trauma consultation service (GTCS) models have been associated with better delivery of geriatric care and functional outcomes. Whether such collaborative models can be improved and sustained remains uncertain. We describe the sustainability and process improvements of an inpatient GTCS. METHODS: We assessed workflow using interviews and surveys to identify opportunities to optimize the referral process for the GTCS. Sustainability of the service was assessed via a prospective case series (July 2012-December 2013). Study data were derived from a review of the medical record and trauma registry database. Metrics to determine sustainability included volume of cases, staffing levels, rate of adherence to recommendations, geriatric-specific clinical outcomes, trauma quality indicators, consultation requests and discharge destination. RESULTS: Through process changes, we were able to ensure every eligible patient was referred for a comprehensive geriatric assessment. Compared with the implementation phase, volume of assessments increased and recommendation adherence rates were maintained. Delirium and/or dementia were the most common geriatric issue addressed. The rate of adherence to recommendations made by the GTCS team was 88.2%. Only 1.4% of patients were discharged to a nursing home. CONCLUSION: Workflow assessment is a useful means to optimize the referral process for comprehensive geriatric assessment. Sustainability of a GTCS was shown by volume, staffing and recommendation adherence.

Les modèles de services de consultation proactifs en traumatologie gériatrique ont été associés à une amélioration des soins gériatriques et des capacités fonctionnelles. Toutefois, on ignore toujours s'il est possible de perfectionner et de maintenir ces modèles collaboratifs. Nous décrivons donc ici la viabilité et l'amélioration des procédures d'un service de consultation en traumatologie gériatrique en milieu hospitalier.

Discovering Their Needs: Southern Rural Women of East India.

This qualitative, descriptive, phenomenological study explored how southern, rural women in India (N = 14) view health, how they learned about health, and what health education they desired. Health education classes were offered, based on participants' responses. Recommendations are offered for a best practice model that could potentially enhance the efforts of non-Indian nurses desiring to assist impoverished women and families in India.

Fate of polyfluoroalkyl phosphate diesters and their metabolites in biosolids-applied soil: biodegradation and plant uptake in greenhouse and field experiments.

Significant contamination of perfluoroalkyl acids (PFAAs) in wastewater treatment plant (WWTP) sludge implicates the practice of applying treated sludge or biosolids as a potential source of these chemicals onto agricultural farmlands. Recent efforts to characterize the sources of PFAAs in the environment have unveiled a number of fluorotelomer-based materials that are capable of degrading to the perfluoroalkyl carboxylates (PFCAs), such as the polyfluoroalkyl phosphate diesters (diPAPs), which have been detected in WWTP and paper fiber biosolids. Here, a greenhouse microcosm was used to investigate the fate of endogenous diPAPs and PFCAs present in WWTP and paper fiber biosolids upon amendment of these materials with soil that had been sown with Medicago truncatula plants. Biodegradation pathways and plant uptake were further elucidated in a separate greenhouse microcosm supplemented with high concentrations of 6:2 diPAP. Biosolid-amended soil exhibited increased concentrations of diPAPs (4-83 ng/g dry weight (dw)) and PFCAs (0.1-19 ng/g dw), as compared to control soils (nd-1.4 ng/g dw). Both plant uptake and biotransformation contributed to the observed decline in diPAP soil concentrations over time. Biotransformation was further evidenced by the degradation of 6:2 diPAP to its corresponding fluorotelomer intermediates and C4-C7 PFCAs. Substantial plant accumulation of endogenous PFCAs present in the biosolids (0.1-138 ng/g wet weight (ww)) and those produced from 6:2 diPAP degradation (100-58 000 ng/g ww) were observed within 1.5 months of application, with the congener profile dominated by the short-chain PFCAs (C4-C6). This pattern was corroborated by the inverse relationship observed between the plant-soil accumulation factor (PSAF, Cplant/Csoil) and carbon chain length (p < 0.05, r = 0.90-0.97). These results were complemented by a field study in which the fate of diPAPs and PFCAs was investigated upon application of compost and paper fiber biosolids to two farm fields. Together, these studies provide the first evidence of soil biodegradation of diPAPs and the subsequent uptake of these chemicals and their metabolites into plants.

Investigating the biodegradability of a fluorotelomer-based acrylate polymer in a soil-plant microcosm by indirect and direct analysis.

Fluorotelomer-based acrylate polymers (FTACPs) are a class of side-chain fluorinated polymers used for a variety of commercial applications. The degradation of FTACPs through ester hydrolysis, cleavage of the polymer backbone, or both could serve as a significant source of perfluoroalkyl carboxylates (PFCAs). The biodegradation of FTACPs was evaluated in a soil-plant microcosm over 5.5 months in the absence/presence of wastewater treatment plant (WWTP) biosolids using a unique FTACP determined to be a homopolymer of 8:2 fluorotelomer acrylate (8:2 FTAC). Although structurally different from commercial FTACPs, the unique FTACP possesses 8:2 fluorotelomer side chain appendages bound to the polymer backbone via ester moieties. Liberation and subsequent biodegradation of the 8:2 fluorotelomer appendages was indirectly determined by monitoring for PFCAs of varying chain lengths (C6-C9) and known fluorotelomer intermediates by liquid chromatography tandem mass spectrometry (LC-MS/MS). A FTACP biodegradation half-life range of 8-111 years was inferred from the 8:2 fluorotelomer alcohol (8:2 FTOH) equivalent of the unique FTACP and the increase of degradation products. The progress of FTACP biodegradation was also directly monitored qualitatively using matrix-assisted laser desorption/ionization (MALDI-TOF) time-of-flight mass spectrometry. The combination of indirect and direct analysis indicated that the model FTACP biodegraded predominantly to perfluorooctanoate (PFOA) in soils and at a significantly higher rate in the presence of a plant and WWTP biosolids.

Cereblon-Targeting Ligase Degraders in Myeloma: Mechanisms of Action and Resistance.

Cereblon-targeting degraders, including immunomodulatory imide drugs lenalidomide and pomalidomide alongside cereblon E3 ligase modulators like iberdomide and mezigdomide, have demonstrated significant anti-myeloma effects. These drugs play a crucial role in diverse therapeutic approaches for multiple myeloma (MM), emphasizing their therapeutic importance across various disease stages. Despite their evident efficacy, approximately 5% to 10% of MM patients exhibit primary resistance to lenalidomide, and resistance commonly develops over time. Understanding the intricate mechanisms of action and resistance to this drug class becomes imperative for refining and advancing novel therapeutic combinations.

Just scratching the surface: novel treatment approaches for multiple myeloma targeting cell membrane proteins.

A better understanding of the roles of the adaptive and innate immune systems in the oncogenesis of cancers including multiple myeloma (MM) has led to the development of novel immune-based therapies. B cell maturation antigen (BCMA), G protein-coupled receptor family C group 5 member D (GPRC5D) and Fc receptor-like protein 5 (FcRL5, also known as FcRH5) are cell-surface transmembrane proteins expressed by plasma cells, and have been identified as prominent immunotherapeutic targets in MM, with promising activity demonstrated in patients with heavily pretreated relapsed and/or refractory disease. Indeed, since 2020, antibody-drug conjugates, bispecific T cell engagers and autologous chimeric antigen receptor T cells targeting BCMA or GPRC5D have been approved for the treatment of relapsed and/or refractory MM. However, responses to these therapies are not universal, and acquired resistance invariably occurs. In this Review, we discuss the various immunotherapeutic approaches targeting BCMA, GPRC5D and FcRL5 that are currently either available or in clinical development for patients with MM. We also review the mechanisms underlying resistance to such therapies, and discuss potential strategies to overcome these mechanisms and improve patient outcomes.

Timing antigenic escape in multiple myeloma treated with T-cell redirecting immunotherapies.

Recent data highlight genomic events driving antigen escape as a recurring cause of chimeric antigen receptor T-cell (CAR-T) and bispecific T-cell engager (TCE) resistance in multiple myeloma (MM). Yet, it remains unclear if these events, leading to clonal dominance at progression, result from acquisition under treatment selection or selection of pre-existing undetectable clones. This differentiation gains importance as these immunotherapies progress to earlier lines of treatment, prompting the need for innovative diagnostic testing to detect these events early on. By reconstructing phylogenetic trees and exploring chemotherapy mutational signatures as temporal barcodes in 11 relapsed refractory MM patients with available whole genome sequencing data before and after CART/TCE treatment, we demonstrated that somatic antigen escape mechanisms for BCMA- and GPRC5D-targeting therapies are acquired post-diagnosis, likely during CART/TCE treatment. Longitudinal tracking of these mutations using digital PCR in 4 patients consistently showed that genomic events promoting antigen escape were not detectable during the initial months of therapy but began to emerge nearly 1 year post therapy initiation. This finding reduces the necessity for a diagnostic panel to identify these events before CART/TCE. Instead, it underscores the importance of surveillance and identifying patients at higher risk of acquiring these events.

ETV4-Dependent Transcriptional Plasticity Maintains MYC Expression and Results in IMiD Resistance in Multiple Myeloma.

Immunomodulatory drugs (IMiD) are a backbone therapy for multiple myeloma (MM). Despite their efficacy, most patients develop resistance, and the mechanisms are not fully defined. Here, we show that IMiD responses are directed by IMiD-dependent degradation of IKZF1 and IKZF3 that bind to enhancers necessary to sustain the expression of MYC and other myeloma oncogenes. IMiD treatment universally depleted chromatin-bound IKZF1, but eviction of P300 and BRD4 coactivators only occurred in IMiD-sensitive cells. IKZF1-bound enhancers overlapped other transcription factor binding motifs, including ETV4. Chromatin immunoprecipitation sequencing showed that ETV4 bound to the same enhancers as IKZF1, and ETV4 CRISPR/Cas9-mediated ablation resulted in sensitization of IMiD-resistant MM. ETV4 expression is associated with IMiD resistance in cell lines, poor prognosis in patients, and is upregulated at relapse. These data indicate that ETV4 alleviates IKZF1 and IKZF3 dependency in MM by maintaining oncogenic enhancer activity and identify transcriptional plasticity as a previously unrecognized mechanism of IMiD resistance. SIGNIFICANCE: We show that IKZF1-bound enhancers are critical for IMiD efficacy and that the factor ETV4 can bind the same enhancers and substitute for IKZF1 and mediate IMiD resistance by maintaining MYC and other oncogenes. These data implicate transcription factor redundancy as a previously unrecognized mode of IMiD resistance in MM. See related article by Welsh, Barwick, et al., p. 34. See related commentary by Yun and Cleveland, p. 5. This article is featured in Selected Articles from This Issue, p. 4.