A 29-year-old woman with Crohn's disease involving the terminal ileum and proximal colon is on azathioprine and mesalazine. She presents with a severe flare (CRP 78 mg/L, CDAI 380). She fails IV steroids over 5 days. Which biological agent has regulatory approval as induction therapy in this setting?

• A Ustekinumab
• B Certolizumab pegol
• C Tofacitinib
• D Infliximab ✓

Explanation

Infliximab (anti-TNF monoclonal antibody) has the strongest evidence base for induction in steroid-refractory moderate-to-severe Crohn's disease and is most widely used. The ACCENT I trial established infliximab as induction and maintenance therapy. Vedolizumab (integrin inhibitor) and ustekinumab (anti-IL12/23) are approved for Crohn's but are typically used after anti-TNF failure in many guidelines. Tofacitinib (JAK inhibitor) is approved for ulcerative colitis, not Crohn's disease.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.