Citations

Abstract Background: Bispecific T cell engagers (BTCEs) have transformed the treatment of multiple myeloma (MM) and B cell malignancies by redirecting cytotoxic T cells toward malignant targets. While clinical responses can be deep and durable, the immunological determinants of BTCE efficacy, and mechanisms of eventual immune escape, remain poorly understood. Regulatory T cells (Tregs), enriched early in MM, are classically immunosuppressive, but whether they are modulated by BTCEs and contribute to therapeutic outcomes has not been systematically investigated. Methods We performed longitudinal single-cell RNA/TCR/ATAC-sequencing and immune profiling of 17 newly diagnosed multiple myeloma (NDMM) patients across induction therapy. 11 patients were treated with teclistamab plus daratumumab, lenalidomide, and dexamethasone (Tec-DRD, n = 11) in the ongoing MajesTEC-5 (HD10/DSMMXX) trial (NCT05695508). As controls, patients receiving standard-of-care DRD (n = 6) were included. Functional validation used newly established NDMM plasma cell-T cell co-cultures, real-time killing assays, cytokine ELISAs, intracellular flow cytometry and arrayed quantitative PCRs of key T cell signaling pathways. Mechanistic studies employed CRISPR-mediated perturbations and combination treatments with IMiDs. Generalizability was tested using three BTCEs in vitro: teclistamab (BCMA×CD3), blinatumomab (CD19×CD3), and glofitamab (CD20×CD3) to redirect primary human Tregs towards MM (MM.1S), lymphoma (Raji), and B-ALL (NALM-6) cell lines. Non-targeting BTCEs as well as anti-CD3 antibodies were used as controls. Preclinical in vivo studies used an immunocompetent, transplantable Bcma+ Vk*MYC tumor model treated with murinized BTCE surrogates and IMiDs. Results BTCE therapy induced robust transcriptional and epigenetic reprogramming of bone marrow Tregs into a FOXP3lowIL2RAlow cytotoxic phenotype (“exTregs”) expressing NKG7, GZMA/B, TBX21, and CCL5. In contrast, this Treg phenotype conversion was absent in DRD-treated controls. Although comprising only ~2% of marrow-infiltrating T cells, exTregs mediated direct plasma cell lysis in vitro, strictly dependent on BTCE-mediated antigen-specific synapse formation and not recapitulated by CD3 stimulation alone. IMiDs synergized with BTCEs by destabilizing the suppressive Treg phenotype via Helios (IKZF2) downregulation, augmenting granzyme and cytokine production. Single-cell ATAC-seq of Tregs isolated from Tec-DRD-exposed trial participants revealed increased chromatin accessibility at AP-1 motifs and we confirmed BATF/JUNB-driven AP-1 signaling as a central transcriptional axis orchestrating Treg effector conversion in vitro. This cytotoxic reprogramming was conserved across BTCEs targeting BCMA, CD19, and CD20, and validated in immunocompetent mouse models, indicating a generalizable, BTCE-driven mechanism of Treg repurposing, rather than target- or engager-specific biology. Conclusion Our findings uncover a novel mechanism by which BTCEs actively convert suppressive Tregs into cytotoxic, pro-inflammatory effectors that contribute to tumor clearance. We identified the BATF/JUNB transcriptional axis and IMiD-mediated Helios destabilization as targetable regulators of this process. These results redefine Treg function under BTCE pressure, support rational combination regimens with IMiDs, and suggest exTreg signatures as biomarkers and therapeutic targets to enhance T cell-redirecting immunotherapies across hematological malignancies.

Abstract Background Red blood cell distribution width (RDW) is an easily accessible diagnostic test that is underutilized as a prognostic marker, despite substantial supporting evidence in cancer, cardiovascular diseases, and helathy individuals (Pilling et al. PLoS One 2028;13:e0203504). The association between increased RDW and incident acute myeloid leukemia (AML) has long been suggested in healthy volunteers (Abelson et al. Nature 2019;559:400). We looked into a similar phenomenon in patients with polycythemia vera (PV) or essential thrombocythemia (ET) in large discovery and validation cohorts. Methods A machine learning (ML) approach was used to identify baseline clinical and laboratory parameters that were predictive of leukemic transformation (LT) and develop a predictive model in a large discovery cohort of PV and ET, obtained from electronic medical records of the Maccabi Healthcare Services (MHS; Tel-Aviv, Israel). Receiver operating characteristic (ROC) curve analysis was utilized to determine the optimal cutoff points for RDW and other continuous variables. Mayo Clinic databases (Rochester, MN, USA) for patients with PV and ET were utilized as validation cohorts. Identification of study patients in the latter was according to the International Consensus Classification (Arber et al. Blood 2022; 140:1200) while in the discovery cohort was based on presence of ICD-9 codes associated with documentation of disease-specific driver mutations or treatment records that are consistent. Statistical analyses were performed using the R statistical software 4.4.2 (November, 2024) (Foundation for Statistical Computing, Vienna, Austria) or JMP Pro 18.0.0 software (SAS Institute, Cary, NC, USA). Results The discovery cohorts from Israel included 4,592 patients with PV (median age 63 yesrs; 53% males) and 5,968 with ET (median age 61 yesrs; males 40%). The validation cohorts from the Mayo Clinic included 633 PV (median 65 years; 51% males) and 634 ET (median 60 years; females 64%) patients that were informative for RDW. In the discovery cohorts, median follow-up (incident AML) was 6.1 years (N=186; 4.1%) in PV and 6.1 years (N=85; 1.4%) in ET. The corresponding values for the validation cohorts were 6.6 years (N=24; 3.8%) in PV and 7.0 years (N=22; 3.5%) in ET. Discovery cohort analyses Covariate-adjusted Cox regression analysis was utilized to estimate associations between LT and several clinical variables followed by machine learning pipeline to predict LT in a given timeframe. Conversion from continuous to binary variables was accompliched by ROC analysis. Shapley Additive exPlanations (SHAP) application enabled selection of top-ranked features that included RDW >15.5 (HR 3.2, 1.1-9.5; p=0.03), age >60 years (HR 2.9, 1.4-5.9; p<0.01), and LDH >1.5 x UNL (HR 4.0 (1.6-10.0; p<0.01). A similar analysis in ET also identified RDW >15.5 (p<0.01), age >60 years (p=0.01) as well as male sex (p=0.03) as independent risk factors for LT. Subseqent risk models based on these risk factors were externally validated and enabled robust risk stratification with 10-20 year AUCs rangening from 0.75 to 0.81. Validation cohorts analyses The indpendent predictive value of increased RDW observed in the discovery cohort was confirmed in the validation cohorts for both PV and ET and further gender-specified: female/male RDW ≥16.4/15.8 in PV (HR 7.9, 1.9-33.8) and ≥16.1/14.4 in ET (HR 5.1, 2.2-11.9). Also confirmed were the additional prognostic contributions of age ≥60 years (HR 3.8, 1.3-10.9) and LDH >1.5 x UNL (HR 3.9, 1.6-9.4), in PV, while no other clinical risk factor showed RDW-independent prognostic relevance in ET. The prognostic impact of RDW in ET was most apparent in females (p<0.01), as opposed to males (p=0.32) while the effect was equally significant in PV. In multivariable analysis that included previously recognized high risk mutations in PV (SRSF2) and ET (SF3B1), both RDW and mutations sustained significance (p<0.05). Conclusion The current study identifies higher RDW as a key risk factor for LT in both PV and ET, independent of other clinical or genetic risk factors. Possible underlying mechanisms include increased RDW as a marker of long-term pre-leukemic clones with sub-clinical ineffective erythropoiesis or an associated pro-leukemic inflammatory state.

Abstract Background: Multiple myeloma (MM) remains incurable, though key advances such as chimeric antigen receptor T-cells (CAR-T) and immunomodulatory agents, now evolving toward cereblon E3 ligase modulatory drugs (CELMoDs), have substantially improved the longevity and quality of life for patients (pts). Idecabtagene vicleucel (ide-cel) is a CAR-T targeting B-cell maturation antigen (BCMA), now US FDA-approved for pts who have received ≥2 prior lines of therapy including a proteasome inhibitor, immunomodulatory agent, and CD38 monoclonal antibody. Ide-cel was initially FDA-approved for ≥4 prior lines of therapy based on the KarMMa-1 study, which demonstrated a median progression-free survival (PFS) of 8.8 months across all cell doses and median overall survival (OS) of 19.4 months (Munshi et al., New Eng J Med 2021). Although promising, the fact that virtually all pts relapse post-ide-cel indicates that further progress is needed. To that end, iberdomide is an investigational CELMoD that in combination with dexamethasone has demonstrated a 30% response rate in early phase studies of triple class-refractory MM (Lonial et al., Lancet Haem 2022). Additionally, in laboratory-based correlative studies, iberdomide, at doses of ≤1 mg (well below the recommended phase 2 dose of 1.6 mg) was shown to augment immune function, including enhanced T-cell activation and cytotoxicity, and modulation of the cytokine milieu (Amatangelo et al., Cell Rep Med 2024). Iberdomide's combined properties of direct MM cytotoxicity and T-cell potentiation have clear, potential relevance to CAR-T clinically, providing the conceptual basis for the CADMIUM study (NCT06179888), exploring the effects of iberdomide as post-ide-cel maintenance therapy in MM. Study Design and Methods: This is a randomized phase II trial with a safety run-in to evaluate if treatment with iberdomide maintenance post-ide-cel can significantly improve PFS vs. standard of care (SOC) observation without therapy, in pts with relapsed/refractory MM with ≥4 prior lines of therapy, who have received ide-cel within 3 months of registration, and no evidence of MM progression or additional MM therapy since ide-cel. Pre-ide-cel iberdomide exposure is permissible but refractoriness is not. The safety run-in will confirm tolerability of the iberdomide dose to be carried forward, where doses to be tested include: iberdomide 1 mg orally on days 1-21 of a 28-day cycle (dose level 1; DL1) and iberdomide 0.7 mg on days 1-21 of a 28-day cycle (DL2). Dose-limiting toxicities (DLTs) include any of the following during the DLT period of a pt's first three months on iberdomide: prolonged Grade 3 non-hematologic toxicities, Grade 4 non-hematologic toxicities, prolonged Grade 4 neutropenia or thrombocytopenia, or any adverse event requiring iberdomide interruption for >4 weeks. Six pts will be enrolled onto DL1; if at most 1 of these pts has a DLT, DL1 will be carried forward to the randomized part of the study. Otherwise, 6 pts will be enrolled onto DL2. The randomized part of the trial will randomize 60 pts 1:1 to either iberdomide or SOC observation without therapy. A 1-sided log-rank test with α=0.15 has 81% power to detect a true hazard ratio (iberdomide/SOC) of 0.55 or less, corresponding to an improvement in median PFS to 16 vs. 8.8 months with SOC. One interim analysis for futility is planned. Secondary outcomes include OS, best response by International Myeloma Working Group (IMWG) criteria, and deepening of response, particularly conversion to complete response with a bone marrow minimal disease-negative state by Adaptive clonoSEQ (sensitivity 1e-6). Robust correlative studies will include CAR-T persistence, assays of T- and other immune cell function, and pathological analyses of whether BCMA expression on MM cells (prior to enrollment or at relapse) or other markers predict clinical outcomes. Study status: To date, 12 pts have been screened, with 7 pts enrolled on study as part of the safety run-in (1 patient replaced). Enrollment data will be updated at presentation. Notably, an amendment is forthcoming which will enhance correlative studies and broaden eligibility criteria to include patients who have received ≥2 prior lines of therapy, conforming with ide-cel's current FDA label. Study COI: BMS is supporting correlative studies. Study Support: U10CA180821, U10CA180882; BMS; U10CA180868 (NRG Oncology); http://acknowledgements.alliancefound.org

Abstract Background: Polycythemia vera (PV) is characterized by excessive erythrocytosis and elevated hematocrit (Hct), which is associated with increased risk of thrombotic events. Controlling Hct levels (<45%) is a key therapeutic goal to reduce thrombotic events. Sapablursen (ISIS 702843) is a liver-directed, ligand-conjugated antisense oligonucleotide that suppresses transmembrane serine protease 6 (TMPRSS6) to enhance hepcidin production thereby restricting iron availability and reduced erythrocytosis. We are reporting the topline results of the IMPRSSION study (NCT05143957), an ongoing global, open-label phase 2 trial evaluating the safety and efficacy of sapablursen for Hct control and reducing phlebotomy rate in patients with PV. Methods: Eligible patients met 2016 WHO diagnostic criteria for PV, were required to have >3 phlebotomies within six months prior to screening, including >1 phlebotomy in the last 12 weeks. There were no exclusions for HCT prior to randomization. Patients received monthly subcutaneous doses of sapablursen in Cohort A (high dose) or Cohort B (low dose), during a 37-week treatment period. The primary efficacy endpoint was the reduction in the frequency of phlebotomy during the last 20 weeks of the treatment period (Week 17-37) compared to baseline (defined as the mean weekly phlebotomy rate during the six months prior to screening through the first dose of sapablursen). Phlebotomy was performed when Hct levels were ≥45% or at the investigator's discretion, confirmation of Hct was not required for phlebotomy. Serial assessments of serum hepcidin, TSAT and ferritin were conducted. The 10-item Myeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (MPN-SAF-TSS) assessed the change in symptoms from baseline to Week 37. Results: Forty-nine (49) patients received at least one dose of sapablursen (full analysis set) in either Cohort A (n=32) or Cohort B (n=17). The median age was 61 years, 40 (82%) were male, and 29 (59%) classified as high risk. The primary endpoint was met at both dose levels. The weekly phlebotomy rate (mean±SD) decreased from baseline of 0.15±0.07 (~7.8/yr) to 0.05±0.09 (~2.6/yr) during the primary endpoint window (Week 17-37) in Cohort A (n=32, p<0.0001; 95%CI, -0.13, -0.07), and from 0.17±0.07 (~8.9/yr) to 0.07±0.07 (~3.6/yr) in Cohort B (n=17, p=0.0001; 95%CI, -0.14, -0.06). The mean MPN-SAF-TSS was reduced at Week 37 by 32% in Cohort A (change from baseline LSM -6.2, p=0.005) and 11% in Cohort B (change from baseline LSM -2.7, p=0.344). The proportion of patients with Hct control (<45%) without phlebotomy from week 17 to 37 in Cohort A and B was 53% (17/32) and 35% (6/17), respectively. Serum hepcidin was increased from baseline values of 0.25±0.6 to 5.05±4.7 nM at Week 13 in Cohort A (p<0.0001) and from 0.68±1.7 to 2.06±3.6 nM in Cohort B (p=0.0142). A sustained low TSAT was observed between Weeks 17-37 (6.0±2.1% and 5.5±2.0% in Cohort A and 8.9±5.0% and 7.0±3.4% in Cohort B). Serum ferritin increased over time from 18±22 ng/mL and 28±58 ng/mL at baseline in Cohort A and B, respectively, to 44±47 ng/mL and 41±85 ng/mL at Week 37, respectively. Sapablursen was generally safe and well-tolerated. The incidence of injection site reactions was 12.2% (6/49). Injection site reactions did not recur following multiple injections, were not progressive and resolved spontaneously. There was one death on study due to transformation to AML which was deemed as not related to the study drug. Conclusions: Treatment of PV patients with sapablursen increased serum hepcidin, controlled Hct, reduced phlebotomy need and improved quality of life in a dose-dependent manner. These findings highlight the potential of sapablursen as a therapeutic approach in PV and support further development.

Background Transthyretin amyloid cardiomyopathy (ATTR‐CM) has a specific pathophysiology, with myocardial stiffening and systolic dysfunction only in advanced stages. We aimed to investigate the response to cardiac resynchronization therapy (CRT) in ATTR‐CM compared with heart failure. Methods In this multicenter, observational study, patients with ATTR‐CM receiving CRT (n=101) were matched to patients without amyloid cardiomyopathy by sex, age, and implantation type (CRT with versus without defibrillator versus conduction system pacing, upgrade versus first implant). We evaluated changes in QRS duration and echocardiographic parameters following CRT implantation and at the most recent available assessments. The study end points were all‐cause death alone or combined with heart failure hospitalization. Results Patients with ATTR‐CM (median age, 76 [interquartile range, 72–83] years, 98% men, left ventricular (LV) ejection fraction 30% [26–33]) showed greater QRS shortening after CRT implantation ( P =0.012), but not after a median of around 1 year ( P =0.152). There were no significant differences in the absolute LV ejection fraction changes immediately after implantation (+7 [+2/+10] versus +3 [0/+9] units; P =0.124), or to the last echo ( P =0.796), which was performed after 1.3 years in patients with ATTR‐CM and 2.9 years in patients without amyloid cardiomyopathy. Patients with ATTR‐CM had a shorter survival than controls ( P <0.001 for both end points). Patients with ATTR‐CM experiencing an early improvement in LV ejection fraction had a longer survival (log‐rank, 4.3; P =0.038). Conclusions Following CRT implantation, patients with ATTR‐CM show QRS narrowing and improvement in LV ejection fraction, not different from patients without amyloid cardiomyopathy. Early favorable LV remodeling seems to be associated with a lower risk of all‐cause death.

Abstract Advocacy has long been at the core of the infectious diseases (ID) field, with clinicians and researchers advocating to ensure patients can access the care they need on an individual and global scale. The Infectious Diseases Society of America Training Program Directors’ (PD) Committee met in 2024 and discussed ways that advocacy is and should be incorporated into fellowship training, as well as highlighted the role PDs play in advocating for their trainees. Policies with a negative impact on ID clinical care, public health, and research underscore the importance of mobilizing the field of ID to advocate for the patients and communities we serve, as well as for ourselves. This paper presents ideas generated at this meeting and is meant to serve as a reference for ID PDs, as well as the wider ID community, as a call to action for teaching and participating in advocacy work.

Summary: Peripheral Artery Disease (PAD) is a significant global health concern, leading to morbidity through progressive stenosis and eventually occlusion of the lower extremity arterial vasculature. Advanced imaging modalities play a major role in diagnosing PAD, in planning endovascular as well as surgical interventions, and in monitoring post-treatment outcomes. This review highlights the current major imaging techniques, including duplex ultrasound, computed tomography angiography (CTA) and magnetic resonance angiography (MRA). It provides insights into their applications, advantages, limitations and the importance of individualized imaging strategies for optimizing patient outcomes.

Abstract Background The past two decades have witnessed tremendous growth in the appreciation and treatment of sacroiliac joint (SIJ) complex pain, including anatomical dissections that shed light on innervation, an appreciation for the contribution of extra-articular components to SIJ complex pain, the advent of radiofrequency ablation (RFA) and a host of minimally invasive surgical techniques. Yet, there is no standardization on diagnosis and treatment paradigms. Methods In February 2023, the Boards of Directors for the American Academy of Pain Medicine (AAPM) and American Society of Regional Anesthesia & Pain Medicine (ASRA-PM) approved the development of multispecialty guidelines on SIJ complex pain. Thirty partner organizations with clinical and scientific interests in SIJ complex pain were identified, and formal letters of request-for-participation were sent to each, along with a request for nominees to serve on the committee. Twenty five organizations agreed to participate in addition to the Departments of Defense and Veterans Affairs. A steering committee developed 21 questions, which spanned criteria for diagnosis, non-interventional and interventional treatments including surgery, technical parameters on how to optimize results, and what constitutes positive outcomes. Questions were methodically assigned to specialized modules comprising 4-5 members with complementary expertise, who collaborated with the Subcommittee Lead and one of three Committee Chairs to develop preliminary drafts. Following thorough revisions, these drafts were subsequently submitted to the full committee for comprehensive review. A modified Delphi method was used in which the answers to questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was achieved. During a committee meeting before commencement, it was agreed that recommendations would be noted when there was &gt;50% agreement among committee members, but that a formal recommendation would require ≥75% consensus. Results Twenty-one organizations formally endorsed the guidelines. The American Society of Anesthesiologists, and American Academy of Physical Medicine & Rehabilitation, and the North American Spine Society affirmed the benefit of the guidelines but did not officially endorse them. The American Academy of Neurology declined to affirm the benefit of the guidelines citing “lack of relevance to their membership.” Per policies, while the Departments of Defense and Veterans Affairs did not formally review the guidelines for endorsement, their representatives approved them. In addition to being endorsed or the benefit affirmed by all voting organizations, complete consensus from committee members was obtained on all 21 questions. On 2 recommendations, there were dissensions from 3 societies who thought that selecting patients for sacral lateral branch RFA and minimally invasive fusion should be based on ≥75% relief from 2 blocks instead of at least 50% relief from a single block before RFA, and greater than 50% pain relief with documented functional improvement after a single block before fusion. One additional society (Latin American Society of Regional Anesthesia) abstained on the statement that the evidence is stronger for extra-articular than intra-articular injections. The committee found that a battery of physical exam tests has reasonable sensitivity, but lower specificity, for identifying intra-articular but not extra-articular pathology, with negative tests having greater predictive value than positive ones. Intra-articular injections have diagnostic validity for SIJ intra-articular, but not extra-articular pain. There is unclear or negative evidence for imaging. The prevalence rates of intra-articular and extra-articular pathology are comparable, with both intra- and extra-articular steroid injections providing at least 4 weeks of relief in well-selected patients. However, the evidence is slightly stronger for extra-articular corticosteroid injections to provide short-term relief. The evidence base for non-interventional therapies is indirect, extrapolated mostly from low back pain studies. There is weak evidence supporting dextrose-based prolotherapy and platelet-rich plasma to provide at least 3 months of pain relief. There is strong evidence for sacral lateral branch RFA to provide relief for at least 6 months in individuals with extra-articular pathology, with face validity and indirect evidence from randomized trials supporting sacral lateral branch blocks as a prognostic tool. There is stronger evidence for larger lesions or more aggressive lesioning strategies than for less stringent techniques. There is weak evidence to support non-steroidal anti-inflammatory drugs to prevent neuritis after RFA, and in most cases anticoagulation does not require cessation in the periprocedural perioid. With an aggressive lesioning strategy, sensory stimulation provides minimal therapeutic benefit, with weak, extrapolated evidence that motor stimulation can provide safety benefit. The cutoff to designate diagnostic or prognostic blocks as positive is most commonly set at 50%, with higher values not shown to improve outcomes for more definitive procedures; for therapeutic treatment outcomes, the evidence supports a lower threshold of ≥30% pain relief or meaningful benefit on non-pain outcomes (eg, opioid cessation) for designation of a positive response. For carefully selected patients with intra-articular SIJ complex pain based on controlled blocks who have failed conservative therapies, there is weak or very weak evidence that minimally invasive SIJ fusion can provide benefit for at least one year. Conclusions SIJ complex pain remains an underappreciated source of chronic low back pain, affecting between 15% and 30% of patients with axial pain predominantly below L5. Answers to many questions were limited by low-quality evidence, indicating the need for better research. SIJ complex pain is a multifarious condition (ie, pain can be from different portions of both the intra- and extra-articular components of the joint) for which an interdisciplinary, multimodal treatment plan can optimize treatment outcomes.