September 2026 Research Update

This month added a clearer picture that cytokine-targeting medicines can help some people with VEXAS for a time, but many patients do not get a strong or lasting overall response. In a 52-person cohort, IL-6 inhibitors and JAK inhibitors had a mix of partial responses, treatment failures, and many stop-switches by 6 to 12 months, which fits with the day-to-day reality of trying multiple options to control flares. IL-1 inhibitors and TNF inhibitors showed little benefit in this group, although only a few people in this study received them, so this result is uncertain. [1]

Looking across drug classes, the study reported that complete responses were uncommon and became rarer over time among those still on treatment. Many people discontinued therapy within the first year, and prednisone dose reductions were variable with only minimal sustained steroid-sparing described across groups. A small subset had genetic clone measurements (variant allele fraction) while on ruxolitinib, and results were mixed: two of five people on ruxolitinib had a clear drop, and the study could not tell whether these changes were linked to clinical response. [1]

For patients and caregivers, this mainly helps set expectations about what has been observed so far when these commonly used inflammation-blocking drugs are tried in VEXAS. The evidence here comes from looking back at real-world care rather than a head-to-head trial, so it cannot prove one option is best, but it does show that many people need to stop or switch within a year and that reducing steroid reliance is often difficult. This matters now as a snapshot of what others have experienced, and later as a starting point for better-designed studies that test which patients are most likely to benefit and for how long. [1]

This month strengthened the idea that VEXAS can involve the blood vessel lining (the endothelium) and the clotting system, not just inflammation symptoms. In a 40-person cohort, about half had a history of blood clots, and blood tests showed a pattern consistent with endothelial activation and increased clotting potential. Together, these results point to a possible biologic reason some people with VEXAS experience thrombosis. [2]

Compared with age-matched controls, patients had higher levels of clot-related proteins such as von Willebrand factor and factor VIII, along with changes suggesting more active clot formation in the blood. The study also reported higher levels of markers linked to activated or stressed blood vessels (including soluble VCAM-1 and soluble thrombomodulin) and changes in von Willebrand factor structure (high molecular weight multimers). These are laboratory signals and do not by themselves explain who will or will not clot, but they help connect VEXAS biology to real complications seen in patients. [2]

For patients, this work mainly adds understanding rather than changing care on its own, because it is based on blood markers and comparisons rather than testing a specific treatment strategy. It helps clarify why clotting problems might be part of VEXAS for some people, by showing a consistent set of blood-vessel and clotting abnormalities alongside a high frequency of thrombosis in this cohort. What remains uncertain is whether these markers can reliably predict clots for an individual person, or which therapies best address this biology, since those questions were not tested here. [2]

This month added a more detailed picture of why inflammation happens in VEXAS, and why it may vary between people with different UBA1 mutations. In 13 patients followed over time, the activity of one gene in blood (RNASE1) tracked disease activity most closely. The same study built laboratory cell models carrying the three common UBA1 mutations. Cell damage and inflammatory signals differed by mutation in a graded order that, according to the authors, matches differences seen between patients with these mutations. [3]

One specific gene signal, RNASE1, rose and fell in step with disease activity in patient samples, making it a candidate marker to study further. In the lab models, the study reported mutation-dependent problems in protein handling inside cells (a stress response) and stronger inflammatory signaling in the mutations described as more severe. When the researchers blocked RIPK3 in these models, the inflammatory and cell-stress features were markedly reduced, which is an early research step toward identifying new drug targets. [3]

For patients and caregivers, this is mostly early-stage research that may matter later if confirmed in larger groups. It helps clarify that VEXAS is not one single inflammatory pattern, and that the specific UBA1 mutation may shape how immune cells behave, which could eventually affect how disease activity is tracked or treated. What remains uncertain is whether RNASE1 will prove useful as a routine blood marker, and whether targeting RIPK3 would be safe and helpful in people, since that part was only tested in laboratory models. [3]

This month's case-based papers emphasized that VEXAS can sometimes take a severe course, especially when intense inflammation overlaps with bone marrow failure. Across these reports, serious inflammatory syndromes (like macrophage activation syndrome) and blood vessel inflammation were described, and some patients had progressive anemia and low blood counts that became difficult to manage. These reports do not show how common these complications are, but they make the range of possible presentations more concrete. [4] [5] [6] [7]

A three-patient series highlighted macrophage activation syndrome (MAS) occurring either during flares or even before VEXAS was recognized, with fever, low blood counts, and very high ferritin reported. The cases improved rapidly after high-dose corticosteroids, and some also received anakinra or etoposide, showing that MAS can be treatable when identified as part of the VEXAS course. The same series also described complications during care, including neutropenia and episodes requiring supportive treatments. [4]

Two individual reports illustrated different high-severity patterns: one autopsy report showed widespread granulocytic vasculitis across multiple organs, where a UBA1 mutation was found years later in stored bone marrow tissue, confirming VEXAS retrospectively. Another report described a man with genetically confirmed VEXAS whose inflammation improved on high-dose steroids, but whose blood counts worsened to transfusion dependence despite other attempted treatments, leading to evaluation for allogeneic stem cell transplantation. Together, these cases underline how VEXAS can combine inflammatory control problems with progressive bone marrow disease. [5] [6]

One additional case described a man with myelodysplastic syndrome and painful neutrophilic skin lesions (Sweet syndrome) whose symptoms improved with high-dose steroids, but genetic confirmation for UBA1 was not done. After starting azacitidine for myelodysplastic syndrome, he developed severe febrile neutropenia and died, highlighting how serious infection risk can be during marrow-suppressing treatment in this clinical setting. Because VEXAS was only suspected, the report mainly adds to the discussion of diagnostic uncertainty when typical features are present but testing is incomplete. [7]

For patients, these case reports mainly add awareness of the kinds of severe events that have been documented in VEXAS, rather than predicting what will happen to any one person. They help clarify that sudden, intense inflammatory syndromes like MAS and extensive blood vessel inflammation can occur, and that blood count problems can progress even when inflammation temporarily improves on steroids. What remains uncertain is how often these situations occur and which approaches work best across many patients, because case reports are small and reflect individual circumstances. [4] [5] [6] [7]