Elobixibat, the first-in-class Ileal Bile Acid Transporter inhibitor, for the treatment of Chronic Idiopathic Constipation.

INTRODUCTION: Elobixibat is the first in class ileal bile acid transporter (IBAT) inhibitor. IBAT inhibitors block ileal absorption of bile acids by: (1) interrupting the enterohepatic circulation of bile resulting in a fall in serum cholesterol and (2) increasing the delivery of bile acids into the colon. Increasing colonic bile acids causes mucosal fluid secretion and enhances colonic motor activity. Changes in colonic physiology may be useful in treating constipation. Areas covered: In this review, the author reviews the prevalence and medical cost of Chronic Idiopathic Constipation (CIC) and the heterogeneity of the CIC patient population as a complicating factor in drug development and clinical care. He also reviews the history of Bile Acid cathartics and the complex pharmacophysiology of bile therapy with fluid and electrolyte shifts, colonic motor function changes and mucosal immunologic activation. Finally, the author reviews elobixabat development and the clinical trials that demonstrate improvement in constipation. Expert opinion: The early phases of elobixibat development provide confirmation of high IBAT binding affinity which translates into the expected inhibition of enterohepatic bile acid circulation and enhanced delivery of ileal bile acids to the colon associated with expected physiological changes. Elobixibat as a treatment of CIC appears promising.