Infliximab (IFX) came into clinical practice in 1998 after impressive results, published in the New England Journal of Medicine, demonstrated remarkable success in refractory Crohn’s disease and even allowed resolution of fistulas. Due to its expense and perceived risks, IFX has been typically reserved for treatment failures & significant perianal disease. Although there have been discussions about ‘top-down’ therapy for many years, more and more it has become apparent that the best opportunity to influence the natural history of Crohn’s disease is early in the course; and perhaps in some cases of ulcerative colitis early IFX treatment may be worthwhile. Clinical experience and treatment trials have shown that IFX response is significantly greater in Crohn’s disease than ulcerative colitis.
Data on the postoperative course of Crohn’s disease has been informative on this approach as have large studies demonstrating that IFX is likely at least as safe as any other medication treatments for moderate-to-severe disease (eg. thiopurines, corticosteroids, methotrexate, tacrolimus). With regard to postoperative Crohn’s disease, it has been shown that microscopic disease may develop within one week of intestinal resection. More than 70% of postoperative patients develop significant mucosal recurrence within 12months (i2 or greater); yet, symptoms may not develop for a much longer time. When significant mucosal disease is present, it may already be too late to achieve optimal response to IFX and similar agents due to remodeling of the intestinal submucosa. Early in the course of Crohn’s disease, the vast majority of patients have an inflammatory phenotype (Cosnes J, et al. Inflamm Bowel Dis. 2002; 8:244-25), whereas later in the course, stricturing and penetrating disease are increasingly common.
Postoperative mucosal scoring system:
• i1 – 5 or fewer apthous lesions
• i2 – more than 5 apthous ulcers with normal mucosa between, or skip areas of larger lesions
• i3 – diffuse apthous ileitis with diffusely inflamed mucosa
• i4 – diffuse inflammation with large ulcers, nodules or narrowing
Rutgeerts et al. Gastroenterology 1990;99:956-83
Benefits: higher efficacy, lower disease-related complications, decrease surgery, improvement in catchup growth/bone formation (both not shown in AZA trials)
Risks: higher costs (but probably cost-effective)
**IFX therapy early may save health care costs by reducing surgery/hospitalizations: Jewell DP et al, Eur J Gastroenterol Hepatol 2005, Leombruno JP et al Pharmacoepidemiol Drug Saf 2011
Conventional approach with accelerated step-up:
Risks: lower efficacy, higher infection risk/mortality with repeated steroids
Benefits: possibly lower cost
Potential drawbacks with azathioprine or 6-mercaptopurine (thiopurine class):
- IBD 2011; 17: 2138. AZA can achieve remission in only ~30%.
- Canc Research 2009; 69: 7004. AZA is carcinogen– incorporated into DNA & changes sun absorption. Skin cancer risk never drops when stopping med.
- Gastro 2011; 141: 1621: CESAME (n=19,486) thiopurines associated with NHL risk. HR 5.28.
- IBD 2009; 15: 1583. Postoperative mgt: low risk (1st surg, short stricture) –>no Rx; moderate risk (<10yrs of dz, long stricture, inflammatory dz)–>6MP; high risk (penetrating dz, >2 surg) –>IFX. Post-op scope @6-12mo
- JPGN 2009; 48 suppl 2: S72
- Clin Gastro & Hep 2009; 7:183. Long term results with surgery for small bowel Crohn’s. n=865 surgeries. Risk for repeat surgeries: younger age, upper small bowel location, stricturing
- Gastroenterology 2009; 136: 441. IFX prevents recurrent Crohn’s post-op. n=24. 1/11 w recurrence vs 11/13 control patients.
- Am J Gastro 2008; 103: S412 (abstract 1054) IFX reduces post-op recurrence. clinical recurrence 0% at week 54 vs 39% of controls. n=23. 90% in IFX group with endoscopic remission vs 15% of placebo group.
- Lancet 2008; 371: 660-667. top-down strategy more likely to achieve endoscopic remicssion after 2yrs: 73% vs 30%. n=129.
- NEJM 2010; 362: 1383. Sonic study. Combination AZA/IFX with greater efficacy. 56.8% remission in combo Rx vs IFX monotherapy.
- Gut 2010; 59: 1363. n=121. Co-treatment helpd reduce complications & flares relative to monotherapy (& azathioprine appeared to be more effective than methotrexate).
- JPGN 2009; 49: 183. REACH pediatric trial showed good perianal dz response to infliximab.