title: Corrigendum.
abstract: In the paper ‘Population pharmacokinetics-pharmacodynamics of vedolizumab in patients with ulcerative colitis and Crohn's disease’ published in Volume 42, Issue 2 (July 2015), an error was found on page 2, column 1 last paragraph—the unit used for the concentration is incorrect. It should be 1–10 μg/mL instead of 1–10 ng/mL. The sentence should read ‘After reaching peak concentrations, vedolizumab serum concentrations fell in a generally biexponential fashion until concentrations reached approximately 1–10 μg/mL’.The authors apologise for this error.