KBI-058 works by inhibiting the apical sodium-dependent bile acid transporter (ASBT), which is primarily responsible for the reabsorption of bile acids in the intestines. By blocking ASBT, KBI-058 reduces the reabsorption of bile acids, thereby increasing their excretion into the feces. This action decreases the enterohepatic circulation of bile acids, which in turn reduces the concentration of bile acids in the liver. The reduction in bile acid reabsorption and the subsequent decrease in liver bile acid levels can help mitigate liver damage and improve liver function in patients with certain liver diseases. By lowering the levels of toxic bile acids within liver cells, KBI-058 aims to slow disease progression and alleviate symptoms associated with these conditions. Clinical Use and Development KBI-058 has been investigated in clinical trials for its potential to treat primary biliary cholangitis (PBC), a chronic autoimmune liver disease characterized by the progressive destruction of the bile ducts within the liver. PBC can lead to cirrhosis, liver failure, and the need for liver transplantation if left untreated.