Methodology and clinical utility of longitudinal UBA1 tracking in VEXAS syndrome

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) is a haemato-inflammatory syndrome genetically defined by somatic mutations in the X-linked UBA1 gene, typically Val/Thr/Leu substitutions at the Met41 hotspot. Clinical manifestations are heterogeneous and refractory to most haemato-rheumatological treatments. To date, no guidelines exist for the management of VEXAS, and scarce is the evidence on methodology and clinical significance of longitudinal UBA1 clonal burden evaluation upon therapy. Here, we validated a method to quantify UBA1 clonal burden and explored its applicability in patients with VEXAS. Given the different treatment interactions, droplet digital polymerase chain reaction (ddPCR) may allow for informed therapeutic decisions and implementation of personalized strategies.