Renal excretion is a minor elimination route of telotristat etiprate. So this trial is intended to assess the drug behaviour in subjects with decreased renal function. This is a staged study with Part B contingent upon the results of Part A. Part A will enrol a total of 16 subjects, eight with severely impaired renal function and eight healthy subjects. Part B with enrol a total of 16 subjects, eight subjects in each additional renal function group, i.e. mildly impaired renal function group and moderately impaired group.