Objective Vacuoles, E1 enzyme, X‐linked, autoinflammatory, somatic syndrome (VEXAS) syndrome is characterized by a complex spectrum of inflammatory and hematologic manifestations. Clinical research to identify effective therapies is urgently needed but is hindered by the lack of validated outcome measures. A VEXAS‐specific disease activity index (DAI) is an essential tool for reliably capturing changes in disease activity over time, thereby supporting clinical research and informing patient care in this emerging disease. This study aimed to develop a comprehensive DAI to assess disease‐related inflammation across affected organ systems in patients with VEXAS syndrome. Methods Inflammatory manifestations of VEXAS were previously identified through a systematic literature review and expert input. A multinational expert advisory committee developed the VEXAS‐DAI using modified Delphi methodology until consensus (defined as ≥75% concurrence) was reached. Item grading was adapted from the Common Terminology Criteria for Adverse Events. Scoring criteria were developed based on 158 test cases using the Physician Global Assessment of Inflammation. Results Consensus on the VEXAS‐DAI was achieved after four Delphi rounds. The index assesses inflammatory activity at the time of evaluation across 12 domains: inflammatory rash, chondritis, periorbital, ophthalmologic, joint, pulmonary, cardiovascular, genitourinary, neurologic, oral and gastrointestinal, renal, and constitutional symptoms. The total score ranges from 0 to 40. Conclusion The VEXAS‐DAI is a novel instrument designed to quantify active inflammation over time in patients with VEXAS. Prospective validation within a clinical trial setting is ongoing. image
PAXIS: A Randomized, Double-Blind, Placebo-Controlled, Dose-Finding Phase 2 Study (Part 1) Followed by an Open-Label Period (Part 2) to Assess the Efficacy and Safety of Pacritinib in Patients with VEXAS Syndrome
VEXAS (Vacuoles, E1 ubiquitin-activating enzyme, X-linked, Autoinflammatory, Somatic) syndrome is a systemic disorder characterized by an overlap of hematologic and inflammatory features. Most patients require chronic use of moderate-to-high doses of glucocorticoids (GCs) to maintain disease control. Data on GC-sparing therapies is limited, and there have been no prospective pharmacotherapeutic trials in VEXAS syndrome published to date. Pacritinib, an oral inhibitor of IRAK1, JAK2, and ACVR1, has emerged as a promising therapeutic option for VEXAS syndrome. The PAXIS trial is the first prospective, randomized pharmacotherapeutic study conducted in this rare and severe disease. Utilizing a novel study design and disease-specific endpoints, the trial will evaluate the efficacy and safety of two dose levels of pacritinib compared with placebo in patients with VEXAS syndrome (NCT06782373, EUCTR: 2024-516347-41-00).
Establishing a consensus definition of VEXAS flare for clinical research
Abstract Objective VEXAS syndrome is a severe systemic haemato-inflammatory disease with heterogeneous clinical presentations. Most patients experience recurrent inflammatory flares despite anti-inflammatory therapy. The lack of accepted definitions of flare in these patients is preventing development of disease activity tools that are essential for conducting clinical trials. We aimed to develop a consensus definition of a VEXAS flare for use in clinical trials. Methods A nine-member international expert advisory committee established a consensus definition of VEXAS flare using modified Delphi methodology. Clinical inflammatory manifestations of VEXAS syndrome were identified through a systematic literature review. Committee members developed a conceptual framework for flare definition, proposed revisions and voted on changes until consensus (≥75% concurrence) was reached. Results Consensus defined VEXAS flare as active inflammatory manifestation(s) of VEXAS syndrome requiring escalation in glucocorticoid therapy. Three flare categories were established: (i) recurrence of a prior documented VEXAS manifestation; (ii) development of a new VEXAS-defining inflammatory manifestation; or (iii) emergence of a new inflammatory manifestation not meeting criteria for A or B. The panel endorsed an independent adjudication committee to assess Category C flares in clinical trials. Conclusions This study proposes a standardized definition of VEXAS flare, providing uniform criteria for identifying VEXAS disease activity. Future research will evaluate its performance in clinical trials.
American College of Rheumatology Guidance Statement for Diagnosis and Management of
VEXAS
Developed by the International
VEXAS
Working Group Expert Panel
Objective Vacuoles E1 enzyme X‐linked autoinflammatory somatic syndrome (VEXAS) is a recently identified rare genetic disorder associated with somatic mutations in the UBA1 gene. VEXAS presents with a combination of inflammatory and hematologic manifestations, leading to increased morbidity and mortality. Methods Given the variability in disease presentation and the limited number of studies to date, no clinical documents currently exist to provide guidance to health care providers about the management of VEXAS. To address this gap, we formed an international multidisciplinary panel of VEXAS experts. Results Through formalized meetings and a voting process, the group developed consensus clinical guidance considerations for the management of VEXAS. These considerations offer practical advice on several key topics: (1) clinical features of VEXAS, (2) UBA1 screening methods, (3) the diagnosis of myelodysplastic syndromes (MDSs) in patients with VEXAS, and (4) prognosis and management. The aim is to provide expert guidance on which patients to test, how to test for VEXAS, how to approach MDS in the context of VEXAS, and considerations for management. Conclusion This work marks the first formal international consensus guidance for VEXAS and is intended to be used as a resource for clinicians seeking to understand the disease and its management.
Translation of cytoplasmic UBA1 contributes to VEXAS syndrome pathogenesis
Abstract Somatic mutations in UBA1 cause vacuoles, E1 ubiquitin-activating enzyme, X-linked, autoinflammatory somatic (VEXAS) syndrome, an adult-onset inflammatory disease with an overlap of hematologic manifestations. VEXAS syndrome is characterized by a high mortality rate and significant clinical heterogeneity. We sought to determine independent predictors of survival in VEXAS and to understand the mechanistic basis for these factors. We analyzed 83 patients with somatic pathogenic variants in UBA1 at p.Met41 (p.Met41Leu/Thr/Val), the start codon for translation of the cytoplasmic isoform of UBA1 (UBA1b). Patients with the p.Met41Val genotype were most likely to have an undifferentiated inflammatory syndrome. Multivariate analysis showed ear chondritis was associated with increased survival, whereas transfusion dependence and the p.Met41Val variant were independently associated with decreased survival. Using in vitro models and patient-derived cells, we demonstrate that p.Met41Val variant supports less UBA1b translation than either p.Met41Leu or p.Met41Thr, providing a molecular rationale for decreased survival. In addition, we show that these 3 canonical VEXAS variants produce more UBA1b than any of the 6 other possible single-nucleotide variants within this codon. Finally, we report a patient, clinically diagnosed with VEXAS syndrome, with 2 novel mutations in UBA1 occurring in cis on the same allele. One mutation (c.121 A>T; p.Met41Leu) caused severely reduced translation of UBA1b in a reporter assay, but coexpression with the second mutation (c.119 G>C; p.Gly40Ala) rescued UBA1b levels to those of canonical mutations. We conclude that regulation of residual UBA1b translation is fundamental to the pathogenesis of VEXAS syndrome and contributes to disease prognosis.