The ITN’s AVATARS study in ANCA-associated Vasculitis (AAV) opened for enrollment today at the University College London. The AVATARS study (Defining Immune Tolerance in ANCA-associated Vasculitis) led by Alan Salama, MD, PhD (University College London) and Peter Merkel, MD (University of Pennsylvania) is a non-interventional, prospective study that will collect blood specimens from patients with AAV with the goal of identifying biomarkers of tolerance.
AAV is a group of autoimmune diseases marked by anti-neutrophil cytoplasmic antibodies (ANCAs) that cause blood vessel inflammation. Untreated AAV can result in serious organ damage and sometimes death. Immunosuppressive drugs can be effective at inducing remission, but an estimated 30-50% of patients will experience at least one relapse over 5 years. For lack of better options, the presence of ANCA antibodies is often used as an indicator of risk for flare, but is not always a reliable predictor of disease activity. To avoid risk, many patients are kept on immunosuppressive drugs unnecessarily, and alternately, some may be taken off who are at risk of relapse. There is a need to better understand sub-clinical disease and develop better markers to predict outcomes and more effectively manage immunosuppression withdrawal.
The AVATARS study will enroll four groups of patients from four clinical sites in the UK to look for tolerance markers at baseline and after 26 weeks. These four groups include: tolerant patients (off immunosuppression with no recent flares; N=35), non-tolerant patients (experienced a recent flare; N=35), clinically stable participants on minimal therapy who are expected to discontinue immunosuppression (N=15), and healthy controls (N=35). Specimens from these three groups will be analyzed for genetic and cellular patterns uniquely associated with a state of tolerance in AAV. This study will build on biomarker observations made from the ITN’s RAVE study (Rituximab for the Treatment of ANCA-associated Vasculitis and Microscopic Polyangiitis), which are currently being further analyzed.