Glycemic control and insulin production were also recently reported in two patients who received an intrahepatic stem cell–derived islet preparation (VX-880), one of whom became insulin independent with fasting or MMTT-stimulated C-peptide levels ≥0.16 nmol l−1 (ref. 32, poster presentation at the Annual Meeting of the American Diabetes Association (2023)). The gene discussed is INS; the disease is diabetes mellitus.