Pongdee, Thanai

Background Systemic corticosteroids (SCS) remain the cornerstone of eosinophilic granulomatosis with polyangiitis (EGPA) and hypereosinophilic syndrome (HES) therapy but are associated with substantial toxicity. Mepolizumab, an anti-interleukin-5 biologic, has demonstrated steroid-sparing effects in addition to EGPA and HES disease control, yet evidence of reductions in SCS-related complications is limited. Methods This retrospective cohort study used US claims data from the Komodo Research Database to quantify SCS-related complications, healthcare resource utilization, and costs in patients with EGPA or HES treated with mepolizumab vs. chronic SCS. Patients were stratified as mepolizumab (300 mg) or chronic SCS users (≥6 months continuous SCS use with >7.5 mg/day for EGPA and >10 mg/day for HES) based on treatment received during a 6-month landmark period post-index (first claim of mepolizumab or SCS). An inverse probability of treatment weighting approach was applied to the cohorts to minimize confounding. Outcomes were assessed up to 12 months post-landmark. Results 578 patients with EGPA (305 mepolizumab users vs. 273 chronic SCS users) and 272 patients with HES (161 vs. 111) were included. In patients with EGPA, rates of any SCS-related complications were 39% lower with mepolizumab compared with chronic SCS (rate ratio [95% confidence interval]: 0.61 [0.49, 0.76], p < 0.001). Mepolizumab users had 57% lower rate of all-cause hospitalizations (0.43 [0.27, 0.69], p < 0.001), and lower outpatient and emergency department (ED) visits vs. chronic SCS. Patients with HES had significantly lower rates of any SCS-related complications with mepolizumab vs. chronic SCS (0.59 [0.42, 0.82], p = 0.002). Mepolizumab users had 66% lower rates of all-cause hospitalizations (0.34 [0.17, 0.65], p = 0.001), and lower outpatient visits relative to chronic SCS users. In EGPA and HES SCS-complication-related hospitalizations and ED visits were lower with mepolizumab compared with chronic SCS. SCS-complication-related medical costs per patient per year were $16,194 ( p = 0.008) and $3,976 ( p = 0.676) lower, in the mepolizumab vs. chronic SCS cohort of patients with EGPA and HES, respectively. Conclusion This first of its kind study suggests that real-world mepolizumab use is associated with reduced SCS-related complications in EGPA and HES, reinforcing its clinical and economic steroid-sparing benefits in reducing healthcare burden among EGPA and HES populations.

Purpose of review Anaphylaxis is a severe type 1 hypersensitivity reaction which is the result of mast cell degranulation causing multiorgan dysfunction. Currently, the most accepted biomarker measurement for mast cell mediated anaphylaxis is serum tryptase measurement. Serum tryptase measurement has limitations including an ideal window of collection during anaphylaxis and must be obtained by venipuncture collection. Urinary mast cell mediators are emerging mast cell biomarkers that can be used for evaluation of mast cell mediated anaphylaxis and mast cell activation. This review will highlight biomarker measurement with urinary mast cell mediators in anaphylaxis. Recent findings This review will highlight biomarker measurement of urinary mast cell mediators including N-methylhistamine, leukotriene E4, and 2,3-dinor-11beta-prostaglandin F2 alpha and their role in anaphylaxis. Summary Urine mast cell mediator collection obtained during acute anaphylaxis and compared to baseline measurements are emerging biomarkers for the detection of mast cell mediated anaphylaxis. Further research is needed to validate the utility of urinary mast cell mediators in anaphylaxis.

Objective To evaluate the effects of mepolizumab therapy on the blood transcriptome in patients with severe eosinophilic asthma (SEA) and to determine whether changes in gene expression predict responsiveness to mepolizumab treatment. Methods Fourteen consecutive patients diagnosed with SEA were prospectively enrolled. Each patient had sequential blood samples obtained pre-initiation and at 4, 8, and 12 weeks post-initiation of mepolizumab. Peripheral blood mononuclear cells (PBMCs) were isolated from blood samples for bulk RNA sequencing. Paired differential expression (DE) gene analysis was performed comparing baseline gene expression versus all timepoints. Changes in gene expression were also compared between responders versus nonresponders to mepolizumab treatment. Finally, gene set enrichment analysis was evaluated across timepoints and its interaction with the response to mepolizumab treatment. Results Principal component analysis of all genes demonstrated a homogeneous distribution, which did not separate into distinct groups based on either timepoint or therapeutic response. At week 12, 149 genes had significant DE (FDR < 0.05) compared to baseline. When performing all-way timepoint comparisons, 74 genes (63 protein-coding) were found to be downregulated at weeks 4, 8 and 12 compared to baseline, but no differences were observed between post baseline timepoints. Twenty-eight genes (16 protein-coding) did change with progression of time and were associated with response to therapy, and 56 protein-coding genes distinguished responders and nonresponders. At week 12, nonresponders had a high enrichment of genes involved with signaling pathways, including cytokines, growth factors, cell differentiation markers, and protein kinases. Conclusion In this exploratory study, mepolizumab use was associated with limited global transcriptomic separation with some preliminary differential-expression and enrichment findings. No definitive mechanistic or predictive response signatures were identified due to the study limitations. Future studies, including larger cohorts followed for longer durations with interrogation of specific immune subsets, may offer additional insight into the pathophysiology of severe eosinophilic asthma and into predicting response to mepolizumab treatment.

Background Respiratory allergic diseases are experiencing changes influenced by genetic factors, environmental shifts, and social and demographic elements. These evolving patterns, together with rapid advances in diagnosis and treatment, require a thorough review of emerging trends. Objective To examine future directions in managing respiratory allergic diseases, focusing on changing disease patterns, environmental factors, diagnostic innovations, and therapeutic advances toward precision medicine. A literature search was conducted in PubMed and Scopus databases covering 2015–2025. Studies addressing human populations with allergic rhinitis or asthma were included, emphasizing emerging patterns, environmental factors, diagnostic technologies, and therapeutic innovations, while reviews, conference proceedings, case reports, and studies without clinical relevance were excluded. Initial screening identified 52 studies, and 21 additional studies were identified through complementary searches, resulting in 73 studies in the final analysis. Summary of findings Climate change is a key factor affecting disease patterns, with pollen seasons starting 10–40 days earlier and yearly emissions increasing by up to 200%. Regarding pathogenesis, early-life rhinovirus C infections with IgE sensitization significantly increase asthma risk (HR = 4.06), while severe asthma shows 40–84% eosinophilic patterns, depending on the assessment approach. On the diagnostic front, advances include multiplex platforms, proteomic biomarkers, and microRNAs. Therapeutically, innovations encompass biologics combined with allergen immunotherapy, nanobody-based therapeutics, and microbiota interventions. Conclusions These developments point toward personalized management of respiratory allergic diseases. However, challenges remain in research with underrepresented populations and accessibility. Moving forward, the key priority is integrating this diverse knowledge into practical strategies that advance precision medicine in respiratory allergic diseases.

ABSTRACT Importance Rural-urban disparities in chronic disease prevalence are well established; however, the extent to which individual-level socioeconomic status (SES) contributes to these disparities remains unclear. Objective To examine the associations of rurality and SES with the prevalence of five most burdensome chronic diseases among adults. Design We conducted a retrospective cross-sectional study of adults across 27 Upper Midwest counties using the Expanded Rochester Epidemiology Project (E-REP) medical record data linkage system to evaluate associations between rurality, SES and chronic disease prevalence. Prevalence of clinically diagnosed asthma, diabetes, hypertension, coronary heart disease, and mood disorders was identified from International Classification of Diseases ICD9/10 codes over a five-year period (2014-2019). Setting Population based Participants Adults over 18 years residing in the 27 E-REP counties, excluding those missing rural-urban residence status. Exposure HOUSES index, an individual-level measure of SES, served as the primary measure, while rurality based on Rural Urban Commuting Area (RUCA) codes 4-10 was the secondary measure. Main Outcome Prevalence of the five clinically diagnosed chronic diseases was identified using ICD9/10 codes from 2014–2019. Mixed effect logistic regression models were used and adjusted for demographics and general medical examination receipt, to assess rural-urban and SES differences for prevalence of each chronic disease. Results Among 455,802 adults with available HOUSES index, 42.8% lived in rural areas, 53.8% were female and 87.4% were non-Hispanic White. In the unadjusted analysis, rural and urban populations showed comparable asthma and CHD prevalence, while mood disorders, hypertension, and diabetes were more common in urban areas. After adjusting for demographic factors and healthcare utilization, rural-urban differences were no longer statistically significant, whereas SES remained strongly associated with all diseases in a dose response manner (e.g., adjusted Odds Ratio for hypertension (ref: HOUSES index Q4): 1.14, 1.27, and 1.42 for HOUSES index Q3, Q2, and Q1, respectively). Conclusions and Relevance Individual-level SES measured by the HOUSES index, was more strongly associated with chronic disease prevalence than rurality, supporting its integration into population health assessment and risk stratification.

Asthma is a heterogeneous chronic respiratory disease driven by diverse inflammatory pathways that vary across patients. The recognition of distinct molecular endotypes has led to the development of targeted biologic therapies that have transformed the management of moderate-to-severe asthma. However, selecting the most appropriate biologic therapy for each patient remains challenging. Health providers often rely on trial-and-error approaches that may delay disease control, increase costs, and expose patients to unnecessary side effects. Biomarkers are key to precision asthma care, as they provide objective measures of underlying disease mechanisms. Established biomarkers such as blood eosinophil count, fractional exhaled nitric oxide, and serum total immunoglobulin E are important for identifying type 2-high asthma. Sputum biomarkers offer direct insight into airway inflammation, but their use is limited by technical complexity and availability across centers. Emerging biomarkers, including proteomic, transcriptomic, metabolomic, and genomic biomarkers, show promise in further refining biologic therapy selection. In addition, digital biomarkers derived from electronic health records, wearable devices, and artificial intelligence-based algorithms offer new opportunities to capture real-world changes in disease and treatment response. Non-medical drivers of health, particularly socioeconomic factors, are increasingly recognized as modifiers of biologic effectiveness and may also be helpful in selecting biologic therapies. This review summarizes the existing evidence on established and emerging biomarkers used to guide biologic therapy selection in asthma. Integrating multiple biomarkers will be essential to improve biological selection, monitor response, and ultimately achieve the goal of remission in asthma.

Background: Mastocytic enterocolitis has been proposed as a cause of chronic diarrhea and abdominal pain, characterized by increased mast cells in gastrointestinal mucosal biopsies. However, its clinical significance remains uncertain. Methods: We present a case report of a patient identified to have high levels of mast cells on gastrointestinal biopsies. We then reviewed cases at Mayo Clinic where patients had >20 mast cells per high-power field (HPF) on gastrointestinal biopsies. Patients with alternative explanations for mast cell elevation, including systemic mastocytosis were excluded. We analyzed demographics, clinical presentations, pathology reports, serum and urine mast cell mediators, inflammatory markers, bone marrow biopsies, motility testing, and treatment responses. Results: We identified 42 patients (30 female and 12 male) with elevated mast cells on biopsy (mean age: 41 y, range: 17 to 81). Mast cells were quantified using KIT (CD117) staining, with no abnormal clumping or morphology, and CD25 immunostaining was negative in all cases. Eosinophilic infiltration was absent in all but one case. Small intestinal bacterial overgrowth (SIBO) was found in 78% of patients tested. Treatments varied widely, with antihistamines and cromolyn being the most common. Among 21 patients with sufficient follow-up, only 5 (24%) reported partial or complete symptom improvement, while 76% experienced persistent symptoms. Conclusion: Routine assessment of mast cells on gastrointestinal biopsies is not supported by our findings. Elevated mucosal mast cells, in the absence of systemic mast cell disorders, may not indicate a distinct disease entity. Evaluation should focus on ruling out other inflammatory, allergic, infectious, and motility disorders, as well as SIBO. Further research is needed to determine the clinical significance of increased mucosal mast cells and their role in gastrointestinal symptomatology.

Abstract Background: The International Consensus Classification (ICC) for systemic mastocytosis (SM) recognizes mast cell leukemia (MCL) and SM with associated myeloid neoplasm (SM-AMN) as distinct categories of advanced SM (SM-Adv; Arber et al. Blood 2022;140:1200). Contemporary risk models in SM, including the Mayo Alliance Prognostic System (MAPS), do not account for the prognostic heterogeneity among ICC-defined SM-Adv subcategories. Methods: Mayo Clinic databases were utilized to access patient information. Diagnoses of SM and its morphological subcategories were confirmed through clinical evaluations and review of BM pathology. Diagnostic criteria were retrospectively fitted to be consistent with those of the ICC (Arber et al. Blood 2022;140:1200); diagnosis of MCL required the presence of immature cytomorphology of mast cells and only myeloid neoplasms were listed under the category of SM-AMN.Next-generation sequencing and cytogenetic studies was performed in a subset of the study patients according to previously described methodologies. Statistical analyses were conducted on clinical and laboratory data collected at the time of initial diagnosis while survival analysis was censored at the time of allogeneic stem cell transplant (ASCT). Results: A total of 910 Mayo Clinic patients with SM (median age 56 years, range 12-89; males 50%) were accessed in order to conduct a series of multivariable analyses (MVA) in search of independent risk factors for transplant-censored overall survival (OS). All patients were evaluable for assignment to specific ICC categories of SM: indolent (ISM; N=553), aggressive (ASM; N=114), SM-AMN (N=235), and MCL (N=8); the AMN components in SM-AMN included acute myeloid leukemia (N=18), chronic myelomonocytic leukemia (N=70), myelodysplastic syndromes (N=32), MDS/myeloproliferative overlap (N=81), myelofibrosis (N=7), polycythemia vera or essential thrombocythemia (PV/ET; N=19), and others (N=8). In addition, subsets of patients were evaluable for hemoglobin level (N= 865), white blood cell count (WBC; N=858), platelet count (N= 859), serum alkaline phosphatase (ALP; N=761), serum tryptase level (N=706), karyotype (N=574), and mutations (N=240). Median follow-up for living patients was 70 months (range, 0-520); during this time 346 (38%) deaths, 16 leukemic transformations, and 20 ASCTs were documented. ROC analysis-determined optimal cutoff levels for predicting OS included age at ≥60 years, platelet count <150 x 109/L, tryptase level ≥100 ng/mL, WBC ≥10 x 109/L, hemoglobin below sex-adjusted lower limit of normal (anemia), and ALP >210 U/L in women or >170 U/L in men (increased). All except WBC ≥10 x 109/L retained significance during MVA that included ICC-specified SM categories: MCL (HR 74.8, 26.0-215.3; p<0.01); SM-AMN (HR 3.9, 2.5-6.0; p<0.01); ASM (HR 2.2, 1.4-3.5; p<0.01); age ≥60 years (HR 3.3, 2.2-4.7; p<0.01); platelets <150 x 109/L (HR 2.8, 2.0-3.9; p<0.01); tryptase ≥100 ng/mL (HR 2.1, 1.5-2.9; p<0.01); anemia (HR 1.7, 1.1-2.4; p<0.01); and increased ALP (HR1.5, 1.1-2.0; p=0.01). A subsequent HR-weighted risk model effectively delineated 5 risk levels ranging in median survivals from 11 months to 372 months (Figure 1). Figure 2 outlines complementary subtype-specific risk models; to that end, risk factors for ISM included age ≥60 years (HR 4.5, 2.5-7.9), tryptase ≥100 ng/mL (HR 3.5, 2.1-6.0); platelets <150 x 109/L (HR 3.4, 1.5-7.9), and anemia (HR 2.4, 1.2-4.8); for ASM age ≥60 years (HR 2.3, 1.3-4.3), platelets <150 x 109/L (HR 2.4, 1.4-4.0), and anemia (HR 2.0, 1.2-3.4); and for SM-AMN age ≥60 years (HR 2.9, 1.6-5.2), platelets <150 x 109/L (HR 2.5, 1.6-3.9), and tryptase ≥100 ng/mL (HR 2.5, 1.6-3.9) [Figure 2]. In SM-AMN, additional prognostic relevance from subcategorization into PV/ET vs. all other types of AMN was appreciated (Figure 3; HR 4.0, 1.6-3.9) and incorporated into the risk model for SM-AMN (Figure 2). Abnormal karyotype (AK) and high risk mutations(HRM; ASXL1, SRSF2, RUNX1, NRAS)clustered withSM-AMN with AK and ASXL1MUT displaying independent prognostic relevance that was most apparent in SM-AMN. Conclusions : MAPS-R relies on the prognostic eminence of ICC-defined morphologic subcategories and allows for additional SM subtype-specific risk stratification. SM associated with ET or PV is a prognostically unique subcategory of SM-AMN and should be recognized as such in future classification schemes. SM-AMN must be thoroughly ruled out in the presence of AK or HRM.

Abstract Introduction: Indolent systemic mastocytosis (ISM) is a clonal mast cell disease driven by the KIT D816V mutation in ~95% of cases and is associated with symptoms of mast cell activation and tissue infiltration. It can cause chronic, debilitating symptoms − including life-threatening anaphylaxis and impaired bone health. While historically most patients have relied on symptom-directed best supportive care (BSC) therapies, avapritinib is used as a new standard of care targeting KIT D816V, the primary driver for SM. Avapritinib is an oral, potent, selective KIT D816V inhibitor, and the first and only approved targeted therapy for adult patients with ISM in the USA and the EU. Approval was based on results from the phase 2 PIONEER trial. Here, we present the findings from ~3.5-year long-term follow-up. Methods: Adults with centrally confirmed ISM and uncontrolled moderate-to-severe symptoms who completed the randomized dose-finding (Part 1), or randomized, double-blind, placebo-controlled (Part 2) portions of PIONEER (NCT03731260) rolled over to the open-label, long-term extension (Part 3). This cumulative analysis includes patients who initiated avapritinib at the recommended dose of 25 mg once daily (QD) in either Parts 1, 2, or 3. All patients received BSC. Per investigator discretion and based on disease burden, dose titration up to 50 mg QD of avapritinib was permitted in Part 3. Long-term efficacy was assessed by measuring changes in symptoms and QoL, using the ISM-Symptom Assessment Form (ISM-SAF; ©2018 Blueprint Medicines, a Sanofi Company) and the Mastocytosis Quality-of-Life Questionnaire (MC-QoL). Safety was also assessed. Results: Overall, 226 patients initiated avapritinib 25mg QD across Parts 1, 2, and 3. This longer-term analysis is inclusive of 65 patients who dose titrated from 25 mg to 50 mg QD in Part 3. Median (range) treatment duration was 40.0 months (0.7‒67.2) as of February 21, 2025. Longer-term efficacy data with ~3.5 years of follow-up demonstrated sustained disease-related symptom improvements. The mean change (standard deviation [SD]) in total symptom score (TSS, per ISM-SAF), was −19.80 (19.81) at Week 144 (Month 33) and −20.43 (20.57) at Week 168 (Month 39) from a baseline of 48.08 (19.47). Additionally, avapritinib-treated patients demonstrated durable improvement in their most severe symptoms (mean change [SD] from baseline of −3.35 [3.02] at Month 33 and −3.47 [3.19] at Month 39) per ISM-SAF. Sustained responses were observed across all individual symptom domains (0–30) with mean changes (SD) at Month 33 and Month 39 of −3.77 (5.52) and −3.84 (6.05) for the gastrointestinal domain, −8.21 (7.70) and −8.20 (7.85) for the skin domain, and −4.66 (6.24) and −4.87 (6.51) for the neurocognitive domain. The mean percent change (SD) in MC-QoL was −34.67 (40.16) at Month 33 and −40.72 (33.24) at Month 39 from a baseline of 54.24 (18.32). Treatment with avapritinib was well tolerated, and its safety profile was similar to the previously reported placebo-controlled portion. Most treatment-related adverse events (TRAEs) were Grades 1–2, and 7% of patients experienced Grade ≥3 TRAEs of which diarrhea, neutrophil count decrease, and weight increase occurred in >1 patient. No Grade ≥3 TRAEs of increase in transaminases were observed. Edema (peripheral and periorbital), the most frequently reported TRAE, was mostly Grade 1 and occurred most frequently during the first 3–4 months of treatment. Three patients (1%) experienced serious adverse events assessed as treatment related. However, none led to treatment discontinuation and no trends were observed. After approximately 3.5 years of follow-up, low rates of treatment discontinuations (n=7, 3%) due to TRAEs were observed. Conclusion: Longer follow-up of patients with ISM treated on the PIONEER trial, including some on avapritinib for up to 5 years, demonstrates that prolonged avapritinib therapy continues to be effective and well tolerated. Additional prospective analyses will be needed to determine effects of selective KIT D816V-inhibition on anaphylaxis. These data support a favorable benefit-risk profile of avapritinib as a chronic treatment for adult patients with ISM.

ABSTRACTThe current study includes 910 patients with systemic mastocytosis (SM) seen at the Mayo Clinic from 1968 to 2024. The primary objective was to examine the prognostic contribution of the International Consensus Classification (ICC), in the context of the Mayo Alliance Prognostic System (MAPS) for SM. World Health Organization classification (WHO‐HAEM5) subcategories included (i) indolent/smoldering SM (ISM/SSM; N = 518), (ii) SM associated with another hematological neoplasm (SM‐AHN; N = 273), with the latter including both myeloid and lymphoid neoplasms, (iii) aggressive SM (ASM; N = 106), and (iv) WHO‐defined mast cell leukemia (MCL; N = 13), which included mast cells with both “mature” and “immature” morphology. The ICC‐defined subcategories were mostly similar with the exception that SM‐AHN was replaced by SM associated with another myeloid neoplasm (SM‐AMN; N = 235) and WHO‐defined MCL was replaced by ICC‐defined MCL (N = 8), which included only those with immature MC morphology. Overall survival (OS) was similar between WHO‐defined MCL (median 1.8 years) vs. SM‐AHN (median 2.3 years; p = 0.3) but significantly different between ICC‐defined MCL (median 0.08 years) vs. SM‐AMN (median 2.0 years; p < 0.01). Significant difference in OS was also apparent between ICC‐defined SM‐AMN and SM associated with lymphoid neoplasm (SM‐ALN; median 8.1 years; HR 3.4; p < 0.01). Multivariable analysis confirmed the inter‐independent prognostic contributions of both ICC‐defined morphologic subcategories and MAPS risk variables, including age > 60 years, anemia, alkaline phosphatase > ULN, and platelet count < 150 × 109/L (p < 0.03 in all instances); the same was not true for WHO‐HAEM5‐defined SM subcategories. The addition of mutational information into the multivariable model resulted in ousting anemia and inclusion of ASXL1 (p < 0.01), SRSF2 (p = 0.01), and NRAS (p = 0.01) mutations as additional risk factors. Classification of SM by ICC is prognostically more accurate, compared to WHO‐HAEM5, and strengthens the prognostic contribution of morphology to current clinical and molecular risk models.