PHOENIX was a Phase 2, open-label, multi-center, US-only trial of bardoxolone methyl in four separate cohorts of patients with autosomal dominant polycystic kidney disease, IgA nephropathy, type 1 diabetic chronic kidney disease, or focal segmental glomerulosclerosis. The trial enrolled 31 patients with autosomal dominant polycystic kidney disease and the primary endpoint was change in estimated glomerular filtration rate at Week 12.