A 45-year-old woman with known primary biliary cholangitis on ursodeoxycholic acid presents with worsening pruritus and fatigue. Labs show ALP 420 U/L, GGT 310 U/L, total bilirubin 2.1 mg/dL, and positive anti-mitochondrial antibodies. She has an inadequate biochemical response to UDCA after 12 months. Which agent is MOST appropriate to add?
- A Methotrexate
- B Obeticholic acid (OCA) ✓
- C Cholestyramine
- D Azathioprine
Explanation
Obeticholic acid is a farnesoid X receptor (FXR) agonist approved as second-line therapy in PBC for patients with inadequate biochemical response to UDCA (defined by the Paris-I/II or Barcelona criteria). It significantly reduces ALP and total bilirubin in these patients. Cholestyramine can relieve pruritus but does not modify disease biology or biochemical markers. Methotrexate and azathioprine are immunosuppressants that have been studied in PBC but are not approved for this indication and have significant toxicity profiles. Neither has demonstrated superiority over UDCA add-on therapy.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.