Designing Smarter Autoimmune Trials for Heterogeneity and Signal Detection Autoimmune diseases represent one of the most complex and heterogeneous areas for drug development, affecting hundreds of millions of patients worldwide. These conditions span a wide spectrum of clinical phenotypes, immunological drivers, and progression patterns. As therapeutic innovation accelerates—particularly with biologics, cell therapies , and targeted immunomodulators— early‑phase clinical development has become t