Simulation Model Projects Outcomes for ANCA-Vasculitis Retreatment Strategies

Researchers have designed a simulation model that projects outcomes from treatment to maintain remission in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, according to a study published online ahead of print in Arthritis Care & Research.

“We developed the AAV-Sim, a microsimulation model of clinical events among individuals with ANCA-associated vasculitis initiating treatment to maintain remission,” wrote corresponding author Zachary S. Wallace, MD, of Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, and coauthors. “Individuals transition between health states of remission or relapse and are at risk for severe infection, end-stage renal disease, or death.”

Developers used transition rates from published studies, stratified by patient-level characteristics, to create the simulation model. Internal validation compared model-projected outcomes over 28 months with actual outcomes from the Rituximab versus Azathioprine in ANCA-Associated Vasculitis 2 (MAINRITSAN2) trial, which compared fixed and tailored retreatment strategies.

According to the study, outcomes for minor relapse, major relapse, severe infection, and relapse-free survival projected by the model were similar to those observed in the MAINRITSAN2 trial. For example, relapse-free survival rates in model projections were 84.8% with fixed and 82.3% with tailored strategies; relapse-free survival rates in MAINRITSAN2 were 86% with fixed and 84% with tailored strategies. Model-projected rates for severe infection were 19.4% for fixed and 11.1% with tailored strategies; MAINRITSAN2 rates for severe infection were 19.8% and 10.2%, respectively.

External validation comparing modeling-projected outcomes for fixed rituximab retreatment with outcomes from MAINRITSAN1 and an observational study yielded similar performance results, the authors reported.

“The AAV-Sim projected a range of clinical outcomes for different treatment approaches that were validated against published data,” researchers wrote. “The AAV-Sim has the potential to inform management guidelines and research priorities.”

—Jolynn Tumolo

Reference

Wallace ZS, Stone JH, Fu X, et al. Development and validation of a simulation model for treatment to maintain remission in antineutrophil cytoplasmic antibody-associated vasculitis. Arthritis Care Res. Published online January 16, 2023. doi:10.1002/acr.25088