(A) The active vitamin B6 metabolite pyridoxal 5’-phosphate (PLP), (B) isoleucine, (C) leucine and (D) valine in plasma of patients with PSC compared to healthy controls. Kaplan-Meier plots showing that low levels (1st quartile) of (E) PLP, (F) isoleucine, (G) leucine and (H) valine were all associated with reduced liver-transplantation free survival in PSC. HC, healthy controls; PLP, pyridoxal 5’-phosphate; PSC, primary sclerosing cholangitis.