CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-07-24). The draft was written by AI, the existence of all 2 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.6.
Verdict No. 1282 · Search date 2026-07-24 · Methodology v0.6

Infliximab,
does it really help with Reduction in colectomy risk through 54 weeks in moderate-to-severe ulcerative colitis?

30-Second Summary
B
Evidence Grade B · 74 · Safety caution
Infliximab reduced 54-week colectomy risk by an absolute 7 percentage points in moderate-to-severe ulcerative colitis
What the
research shows
Infliximab is rated B for reducing colectomy risk through 54 weeks in moderate-to-severe ulcerative colitis. In the prespecified pooled ACT 1 and ACT 2 analysis of 728 participants, cumulative colectomy incidence was 10% with infliximab and 17% with placebo, an absolute reduction of 7 percentage points (P=0.02). Colectomy is a hard clinical endpoint, and clinical response, remission, mucosal healing, and hospitalization moved in the same direction. However, colectomy was not the main primary endpoint of the original ACT trials, the analysis pooled trials and linked data sources, complete follow-up was 87%, and the effect was moderate. These limitations support B with 74 points rather than A.
What the
ads claim
A biologic that prevents surgery does not mean that every patient avoids surgery or is cured long term. About 10% still underwent colectomy within 54 weeks, and loss of response, antidrug antibodies, and infection risk require specialist monitoring of disease activity and treatment.
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Useful facts when choosing a product

  • Infliximab is an intravenously infused anti-TNF-alpha monoclonal antibody. For moderate-to-severe active ulcerative colitis, a common regimen is induction at weeks 0, 2, and 6 followed by maintenance every 8 weeks.
  • Remsima is an infliximab biosimilar. This verdict addresses the infliximab molecule in ulcerative colitis and is separate from verdicts for Crohn disease, rheumatoid arthritis, and other indications.
  • Latent tuberculosis and hepatitis B should be screened before treatment, and serious infection must be monitored during therapy. Infliximab should not be given during an active serious infection.
  • Infusion reactions, opportunistic infection, and reactivation of tuberculosis or hepatitis B can occur. Demyelinating disease, worsening heart failure, and blood disorders are uncommon but important, and live vaccines should be avoided.
Gap Measurement · Verdict 1282 · B 74
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

ACT 1 and ACT 2 each double-masked 364 patients with moderate-to-severe active ulcerative colitis to infliximab 5 mg/kg, 10 mg/kg, or placebo. Week-8 clinical response with 5 mg/kg was 69.4% versus 37.2% in ACT 1 and 64.5% versus 29.3% in ACT 2; remission and mucosal healing were also generally superior. Sandborn and colleagues then pooled colectomy, hospitalization, and surgery data through 54 weeks for all 728 participants. Complete colectomy follow-up was available for 630 participants (87%). Cumulative colectomy was 10% versus 17%, and ulcerative-colitis-related hospitalization was 20 versus 40 events per 100 patient-years. This verdict concerns surgery risk in ulcerative colitis, not infliximab use in Crohn disease or rheumatologic indications.

02

Why this is classified as B (74)

Infliximab reproduced clinical response in placebo-controlled ACT 1 and ACT 2 and reduced 54-week colectomy from 17% to 10% in the pooled analysis of 728 participants. A molecule-specific hard endpoint and consistent supporting outcomes are strong, but colectomy was not the original primary endpoint, complete follow-up was 87%, and the absolute effect was 7 percentage points. This supports B with 74 points.

Counterpoint. For active disease unresponsive to corticosteroids or immunomodulators, reducing surgery risk is clinically important. Hospitalized acute severe ulcerative colitis rescue therapy is not identical to the outpatient moderate-to-severe ACT population, so application requires gastroenterology judgment.

Rejudgment record. New verdict — Applied B because molecule-specific placebo-controlled ACT 1 and ACT 2 trials replicated clinical efficacy and the prespecified pooled 728-patient analysis reduced the hard 54-week colectomy endpoint from 17% to 10%, but colectomy was a pooled secondary rather than original primary endpoint, complete follow-up was 87%, and the absolute effect was moderate

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
Reduced colectomy risk through 54 weeksBPooled randomized data showed 10% versus 17%, a 7-point absolute reduction, but colectomy was not the original primary endpoint.
Achievement of clinical remissionBClinical remission was generally higher than placebo in ACT 1 and ACT 2, with superiority maintained for some doses and time points.
Achievement of mucosal healingBMucosal healing favored infliximab at weeks 8 and 30 in both trials and at week 54 in ACT 1.
Reduced ulcerative-colitis-related hospitalizationBThe 54-week pooled analysis found 20 versus 40 hospitalizations per 100 patient-years.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
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Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Rutgeerts P et al. ACT 1 and ACT 2. 2005Two multicenter randomized double-blind placebo-controlled trials728Sponsored by CentocorWeek-8 clinical response primary endpoint; remission, mucosal healing, and maintained responseWeek-8 clinical response with 5 mg/kg was 69.4% versus 37.2% in ACT 1 and 64.5% versus 29.3% in ACT 2.Core replicated randomized efficacy evidence
Sandborn WJ et al. ACT 1 and ACT 2 colectomy analysis. 2009Prespecified pooled follow-up analysis of two randomized trials87Centocor ACT development programColectomy, hospitalization, and surgery or procedures through 54 weeks after first infusionColectomy was 10% versus 17% (P=0.02; 7-point absolute reduction); ulcerative-colitis hospitalization was 20 versus 40 per 100 patient-years (P=0.003).Key hard surgery endpoint
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Receipt — 2 References

All 2 cited sources were verified for existence at the original page (as of 2026-07-24).

Rutgeerts P, Sandborn WJ, Feagan BG, et al. Infliximab for Induction and Maintenance Therapy for Ulcerative Colitis. N Engl J Med. 2005;353(23):2462-2476. PMID: 16339095. DOI: 10.1056/NEJMoa050516.
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Sandborn WJ, Rutgeerts P, Feagan BG, et al. Colectomy Rate Comparison After Treatment of Ulcerative Colitis With Placebo or Infliximab. Gastroenterology. 2009;137(4):1250-1260; quiz 1520. PMID: 19596014. DOI: 10.1053/j.gastro.2009.06.061.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-07-24 · Corrections: none

Cite this verdict

Infliximab x reduced 54-week colectomy risk in moderate-to-severe ulcerative colitis Evidence Grade B card
[Chamgap] Infliximab x reduced 54-week colectomy risk in moderate-to-severe ulcerative colitis — Evidence Grade B·74. 2 cited sources checked. Source: https://chamgap.com/en/verdicts/gut/infliximab-ulcerative-colitis-54-week-colectomy-risk/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.