Treatment of Pan-Ulcerative Colitis

Medical Necessity and Standard of Care

The American Gastroenterological Association recommends combination therapy with anti-TNF agents and thiopurines for patients with moderate-to-severe ulcerative colitis, particularly those with prior treatment failures, with strong recommendations from multiple major gastroenterology societies (AGA, BSG, ECCO, Toronto Consensus) 1, 2, 3, 4, 5
The 2020 AGA guidelines provide a strong recommendation (moderate-quality evidence) for using infliximab over no treatment for induction and maintenance of remission in moderate-severe UC 3, 4
The UC SUCCESS study demonstrated that patients receiving infliximab plus azathioprine combination therapy achieved significantly higher remission rates (40%) at week 16 compared with infliximab monotherapy (22%) 2
The 2015 Toronto Consensus guidelines provide a strong recommendation (moderate-quality evidence) that anti-TNF therapy should be combined with a thiopurine rather than used as monotherapy to induce complete remission 1

Combination therapy reduces immunogenicity to infliximab, which is particularly relevant given the patient's documented history of immunogenicity 5, 2
The presence of anti-drug antibodies is associated with loss of clinical response, making the azathioprine component critical for maintaining infliximab efficacy 5

The 2020 AGA guidelines provide a strong recommendation for continued anti-TNF therapy to maintain complete remission in patients who respond to induction therapy 3, 4
Therapeutic drug monitoring is strongly recommended (low-quality evidence) to optimize dosing and prevent loss of response 1, 5
The TAXIT trial demonstrated that concentration-based dosing resulted in significantly fewer relapses over 1 year compared to clinical judgment-based dosing 5

The 2019 BSG guidelines confirm azathioprine's benefit over placebo for maintenance of steroid-induced remission (44% vs 65% failure, RR 0.68, 95% CI 0.54 to 0.86) 2
While thiopurines should not be used as monotherapy for induction, they are appropriate for maintenance of remission in selected patients 1