Both trials will assess the safety of NKX019 in people living with autoimmune diseases as well as its ability to enable long-term remissions via a "reset" of the immune system through the elimination of pathogenic B cells. Ntrust-1 is initially enrolling up to 24 patients with lupus nephritis or primary membranous nephropathy. Ntrust-2 is initially enrolling up to 36 patients with systemic sclerosis, idiopathic inflammatory myopathy, or anti-neutrophil cytoplasmic antibody-associated vasculitis. In both studies, patients receive a three-dose cycle of NKX019 on Days 0, 3, and 7 following lymphodepleting conditioning with either fludarabine and cyclophosphamide or cyclophosphamide alone. Leveraging the engineering of NKX019, no patients in either trial will receive supplemental cytokines or antibody-based therapeutics. This approach is designed to evaluate the single-agent activity of NKX019 and facilitate a more rapid path to regulatory approval.