Background In two phase 3 trials, elobixibat, a locally acting ileal bile acid transporter inhibitor, resolved constipation and was well tolerated in Japanese patients with chronic constipation. We analyzed the efficacy, safety, and impact on quality of life (QOL) of elobixibat in patients with symptomatically more severe constipation in the two phase 3 trials. Methods This post hoc analysis of elobixibat treatment outcomes included data from a 2‐week, randomized, placebo‐controlled, phase 3 trial (10 mg/d), and a 52‐week, open‐label trial (5‐15 mg/d) in subgroups with severe constipation defined as ≤2 spontaneous bowel movements (SBMs) and ≤3 Bristol Stool Form Scale score during the second week of the 2‐week run‐in period. We also analyzed the rates of abdominal pain, diarrhea, and QOL in subgroups according to sex, presence of constipation‐predominant irritable bowel syndrome (IBS‐C) and side effects. Key Results In patients with severe constipation, there was significant improvement in the 10 mg elobixibat group compared to the placebo group in change in SBMs from baseline at week 1 (primary endpoint) of the 2‐week trial. The differences between groups were reduced in patients with more severe constipation. Increasing the dose to 15 mg was effective for more severe constipation in improving the number of SBMs per week in the 52‐week trial. Overall, elobixibat was well tolerated and improved QOL scores, irrespective of gender, presence of IBS‐C or side effects. Conclusions & Inferences Elobixibat is effective for symptomatically severe constipation, is well tolerated and improves QOL, irrespective of potentially confounding patient characteristics.

Background and Aim Elobixibat is a locally acting inhibitor of the ileal bile acid transporter. We compared bile acid metabolism between healthy subjects and patients with chronic constipation and assessed changes in the bile acid profile after elobixibat administration in the latter group. Methods Healthy subjects (n = 10) and patients with chronic constipation (n = 19) were assessed as inpatients for 7 days, during which they received meals containing ~60 g/day of fat. Patients with chronic constipation remained as inpatients for a further 7 days for once‐daily elobixibat administration. Assessments included concentrations of fecal and serum bile acids, serum 7α‐hydroxy‐4‐cholesten‐3‐one (C4) and fibroblast growth factor 19, and bowel movements and constipation symptoms. Results Fecal total and primary bile acids were significantly lower in patients with chronic constipation versus healthy subjects. Serum C4 and fibroblast growth factor 19 levels were comparable between groups. Elobixibat treatment increased fecal total and primary bile acids and decreased levels of fecal lithocholic acid and serum total as well as secondary bile acids in patients with chronic constipation. Bowel movements and other constipation‐related symptoms were also improved by elobixibat to levels almost comparable with those of healthy subjects. Conclusions Despite comparable C4 levels, patients with chronic constipation demonstrated decreased levels of fecal bile acids versus healthy subjects. Elobixibat treatment increased fecal bile acid excretion and reduced serum bile acid concentrations. The improvement of constipation after elobixibat treatment was associated with increased total bile acids, particularly primary bile acids.

No abstract