Mékinian, A.

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

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).

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.

AbstractBackgroundVEXAS syndrome is an autoinflammatory disease caused by somatic UBA1 mutations on the X chromosome, predominantly affecting men.ObjectiveTo characterize VEXAS syndrome in women and to compare the features of VEXAS syndrome between sexes.MethodsWe conducted an international, multicenter study, including 12 women and 301 men with genetically confirmed VEXAS syndrome. Data were collected using a standardized case report form. Bone marrow analyses and molecular investigations were performed locally.ResultsClinical features, age at onset, UBA1 mutation type, variant allele frequency, and mortality were comparable between sexes. Acquired X monosomy was found in 6/8 tested women. Additional clonal mutations were present in 3/5 tested women. Three additional UBA1‐mutated women without typical inflammation are described separately.ConclusionVEXAS syndrome affects women with clinical features similar to men, supporting the need for UBA1 testing in women with compatible presentations. X monosomy is common but not universal, suggesting alternative pathogenic mechanisms.

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.

VEXAS syndrome (vacuoles in myeloid progenitors, E1 ubiquitin activating enzyme, X-linked, autoinflammatory manifestations and somatic) is an autoinflammatory condition caused by somatically acquired UBA1 mutations. Heiblig et al report on an international retrospective analysis of 30 patients with VEXAS syndrome treated with different Janus kinase (JAK) inhibitors, finding encouraging evidence supporting the use of the JAK1/2 inhibitor ruxolitinib with clinical remissions and reductions in steroid use seen in the majority of patients.

Abstract Background VEXAS syndrome (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) is due to a somatically acquired mutation of the E1-ubiquitin ligase UBA1, leading to the expression of a catalytically impaired isoform in myeloid cells. VEXAS syndrome combines severe auto-inflammatory manifestations and is frequently associated with myeloid neoplasia (MN). The outcome of VEXAS is poor, and most patients require high dose corticosteroids to reduce inflammation (Bourbon et al. Blood 2021). Therapeutic options besides steroids are currently limited in those patients. In this multicenter retrospective study, we report some clinical efficacy of JAK inhibitors (JAKi) in VEXAS patients. Patients We analyzed retrospectively 24 UBA1 mutated patients (Met41 or previously reported alternative splicing site) treated with JAKi (11 with ruxolitinib (RUXO), 11 with tofacitinib (TOFA), 1 with baricitinib, 1 with upadicitinib) in 7 French, 1 Portugese and 2 US centers. Complete clinical (CCR) and complete biological response (CBR) were defined as complete resolution of clinical symptoms and normalization of inflammation markers (C reactive protein, CRP) respectively. Partial clinical (PCR) and biological (PBR) response were defined by reduction of at least 50% of clinical or inflammation markers, respectively. Results All 24 patients were males with a median age at VEXAS diagnosis of 72 years [range 54-89]. Thirteen had documented myeloid neoplasia (MN) (1 CMML-0, 1 other MDS/MPN, 10 MDS). Clinical manifestations at VEXAS diagnosis include skin involvement (87.5%), arthritis or arthralgia (83.3%), vasculitis (37.5%), fever (75%), ocular manifestations (29.2%) and pulmonary infiltrates (41.6%). IPSS-R was very low/low/intermediate in 8/3/2 cases respectively. Median time between first VEXAS related clinical manifestations and JAKi onset was 2.45 years [0.15-5.45]. Prior to JAKi onset, patients had received a median of 2.5 immunosuppressive/immunomodulatory treatments [range 0-9]. After 1 month, 12/24 (50%) patients had achieved clinical and/or biological response. CCR and CBR was achieved in 7/11 (64%) and 6/11 (54%) patients treated with RUXO, and in 3/13 (23%) and 2/13 (15%) patients treated with other JAKi (figure A). After 3 months, CCR and CBR was 100% and 80% (10 evaluable patients) in the RUXO group as compared to 25% and 25 % in patients treated with other JAKi (8 evaluable patients) (p=0.0036 et 0.0055 respectively, figure B). RUXO efficacy was similar in patients with (n=9) or without (n=2) associated MN. In RUXO treated patients, median CRP and steroid dose reduction was 72.5% [range 21.5- 99.5] and 66.25% [range 0-75] respectively at 3 months. With a median follow-up of 4 months [range 1.4-12], only 1 RUXO treated patient had lost response, whereas median time to next of treatment was 3.4 months with other JAKi (figure C). Of the 13 patients with MN, 7 were RBC transfusion dependent at JAKi onset (6 with RUXO, 1 with other JAKi). Four of 6 patients treated with RUXO achieved RBC transfusion independence at 3 months, but not the patient treated with other JAKi. Regarding safety, severe adverse events were reported in 6 patients: 3 deep vein thrombosis, (2 with TOFA/1 with RUXO), 1 pneumonia (RUXO), 1 enterohemorrhagic E. Coli infection (RUXO), and 1 lethal legionellosis (TOFA)). Conclusion Ruxolitinib (and less often other JAK inhibitors used in this study) provides rapid response in most VEXAS patients, allowing in two third of the cases corticosteroid dose reduction/withdrawal and RBC transfusion independence in 4/6 patients with MN who were initially transfusion dependent. Those retrospective preliminary results, with limited follow up, must be interpreted with caution and will be updated at the meeting. The effect of RUXO on VEXAS patients with concomitant MN will soon be studied prospectively in a Groupe Francophone des Myélodysplasies (GFM) clinical study. Figure 1 Figure 1. Disclosures Galicier: Novartis Pharma Sas, Sanofi Aventis France: Consultancy; Lilly France, Baxalta France, Sanofi Aventis France Sas: Other: Payments as Speaker for Educational Program; Shire France SA, Janssen-Cilag, Pfizer Sas: Other: Invitation to Congress. Hirsch: Novartis Pharma: Consultancy; Daiichi Sankyo Oncology: Consultancy. Warrington: Eli Lilly: Research Funding; Kiniksa: Research Funding. Fenaux: Novartis: Honoraria, Research Funding; JAZZ: Honoraria, Research Funding; Abbvie: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Celgene/BMS: Honoraria, Research Funding; Syros Pharmaceuticals: Honoraria.