Superiority of Anti-TNF Therapy (Part 2)

A recent blog (Superiority of Anti-TNF Therapy in Children | gutsandgrowth) described a recent article showing that kids treated with anti-TNF therapy at the time of diagnosis had improved outcomes compared to children who were treated with other medications.  In this day of multimedia, there is a video explaining the study which may be helpful for families and clinicians alike –here’s the link:  Dr. Michael Stephens discusses the research findings: .

An excerpt from the explanation with the video:

The current research study looks at outcomes and compares three different types of treatments. The first group receives anti-TNF therapy. The second group received immune modulating therapy. The third group received no treatment within the first three months. This study was an observational study and the choice of treatment was at the discretion of the physician. In order to correct for this factor, a statistical technique was used. Patients with similar characteristics were paired within the three groups . The results showed that patients who received the anti-TNF therapy had an improved outcome, such as a higher remission rate and some indications of improved growth, at one year. All three groups had improvements in weight and body mass index but only the anti-TNF group had improvements in linear growth.

Assessing and discussing risk of lymphoma in IBD

A recent article has shown that the absolute lymphoma risk from medications in children and young adults with IBD is quite low (Inflamm Bowel Dis 2012; 18: 838-43).

In this single center study from 1979-2008, 1374 pediatric IBD patients had charts reviewed to determine whether lymphoma developed.  In total, two male patients who had received thiopurines developed lymphoma (one Hodgkin, one anaplastic large cell) in 6624 patient-years of follow-up.  Both patients are alive after chemotherapy.  Mean follow-up was 4.8 years per patient.  The absolute lymphoma incidence rate was 3 per 10,000 patient-years; after thiopurine exposure, the rate was 4.5 per 10,000 patient-years compared to an expected 0.58 per 10,000 patient-years.

In this study, 22% of the patients had received TNF inhibitors.  None developed lymphoma.  The risk of biologics could not be fully assessed due to a limited study period: 713 person-years taking the medication.

The risk of thiopurine-associated lymphoma was similar to previous studies but did not reach statistical significance.  As related in other studies, the risk of biologic agents, like Remicade, Humira, and Cimzia, is heavily influenced by whether patients had also received immunomodulators.

One useful way to try to convey this risk has been with diagrams.  One useful diagram is a palette of one thousand people or of 10,000 people showing the absolute risk and one showing the risk for other complications like infection.  You can make your own by going to the following link:

Download Communication Tools

RiskComm

Additional references/blog entries:

Only one chance to make first impression

Biologics | Living Longer | Arthritis Today Magazine -From Arthritis magazine: biologics improve survival in Rheumatoid arthritis

TNF antagonists and UC

In my fellowship (15 years ago), the use of thiopurines (eg. azathioprine, 6-mercaptopurine) for ulcerative colitis was debated.  Many physicians urged colectomy rather than using these drugs which could have long-term consequences.  At the time, the risk of thiopurines was less well-understood.  Over time, the use of these agents has become common when mesalamine products were ineffective.  The same issue comes up with TNF antagonists versus colectomy.

A recent study provides more information on the effectiveness of adalimumab for patients with moderate-to-severe UC but does not settle this debate (Gastroenterology 2012; 142: 257-65).  In this study, termed ‘ULTRA-2’ (Ulcerative colitis long-term remission and maintenance with adalimumab 2), the  efficacy of adalimumab for induction & maintenance of remission was studied in 494 patients.  This was a randomized, double-blind, placebo-controlled study; average age was 40 years.

Clinical remission in the adalimumab group were 16.5% at 8 weeks (9.3% placebo).  At 52 weeks, 17.3% in the adalimumab group were in remission (8.5% placebo).  Among patients naive to anti-TNF agents, the response rate was 21.3% at week 8 & 22% at week 52.  Safety overall was similar in both groups; however, in the adalimumab group one patient developed gastric cancer and one developed squamous cell carcinoma.

The authors conclude that adalimumab is safe and more effective than placebo in inducing and maintaining remission among patients with moderate-to-severe UC.

A second study, also published this past month, looks at the use of infliximab for maintenance therapy for UC (Inflamm Bowel Dis 2012; 18: 201-11).  Patients who had achieved benefit from ACT-1 and ACT-2 studies were followed for three years.  Dosage of infliximab could be adjusted.  A total of 229 patients entered the study.  During the study, 70 patients (30.6%) discontinued infliximab due to adverse effects (10.5%), lack of efficacy (4.8%) or other reasons (15.2%); the majority were able to continue infliximab.  The authors indicate that no new safety issues were identified. Yet, there were two deaths among the infliximab group including a 19 year-old nonsmoker who developed lung cancer and a lethal case of histoplasmosis.

Because the improvement compared to placebo is modest with both of these agents, the question about whether to use these medications or proceed to surgery in UC patients is unanswered.

Additional references:

  • -Aliment Pharmacol Ther. 2008 Oct 15;28(8):966-72. Epub 2008 Jul 24.  Long-term outcome of adalimumab therapy for ulcerative colitis with intolerance or lost response to infliximab: a single-centre experience.
  • -Am J Gastroenterol (Oussalah A et al) 2010; 105: 2617-25. Multicenter study of IFX for UC
  • -Gastroenterology 2010; 138: 2282. Severe pediatric UC. 25/33 responded to IFX. colectomy rate 19% at 1 year.
  • -Gastroenterology 2009; 137: 1204 (ed), 1250. lower colectomy rates at 54wks in IFX vs placebo (+concomitant meds): 10% vs. 17%.
  • -Clin Gastro & Hep 2008; 6: 1112. Do NOT use CYA post infliximab and vice versa. n=19. 1 death due to sepsis. Remission rates occur in ~1/3rd but are of short duration.
  • -NEJM 2005; 2462. 69% clinical response @ 8 weeks (vs. 37% placebo) & 45% at week 54 (vs. 20% placebo).
  • -JPGN 2004; 38: 298. 82% short-term response, 63% sustained response; n=16.

Methotrexate and liver toxicity

There are drawbacks with all of the therapies for inflammatory bowel disease; however, usually the inflammatory bowel disease is worse than any of the medications. One of the therapies that  has started to see increased usage in Crohn’s disease is methotrexate (MTX), both as an alternative to thiopurines and as an adjunct to Remicade.  There are a number of side effects; a patient handout is available at the following: http://www.ccdhc.org/diseases/MethotrexateLetter.pdf

One of the concerns with MTX has been liver toxicity, in part because of descriptions in the rheumatology literature with long-term usage.  In Crohn’s disease patients, it appears that the risk is much lower (Inflamm Bowel Dis 2012; 18: 359-67).  This study found 13 trials for their meta-analysis.  A total of 632 participants were included: 373 MTX, 131 thiopurines, 128 placebo.  In the MTX group, elevated hepatic aminotransferases occurred in 1.4 per 100 person-months.  The rate of elevation more than 2-fold the upper limit of normal was 0.9 per 100 person-months.  Thus, of the initial 373 patients, 39 had an abnormal aminotransferase.  26 of these 39 had spontaneous resolution, 3 improved with dose reduction & 10 withdrew from MTX treatment (0.8 per 100 person-months).  Seven of these withdrawals were from one of the earlier studies (Feagan et al. NEJM 1995; 332: 292-97). Besides the low likelihood of needing to stop MTX due to liver toxicity, the other observation was that the liver toxicity was mostly dependent on the dose; therefore, dosage reduction would likely be effective if needed.

In my practice, when considering MTX treatment, I usually recommend the following:

  • Monitoring: Baseline: CXR, CBC, Amylase, Renal, LFTs, urine HCG & then Q2-4 weeks initially, then Q3months
  • Give Folate during therapy.
  • Use zofran if needed for nausea
  • Avoid NSAIDs during treatment due to renal toxicity
  • Contraindicated with pregnancy (MTX=teratogen) -females should see gynecology
  • Families warned in writing that this medication is given once a week; more often can be deadly

Additional references:

  • -IBD 2011; 17: 2521. ~25% remission at 1yr, 16% at 2yrs.. n=93.
  • -JPGN 2011;53: 389. n=64. Supports use of zofran for 1st few months to prevent nausea.
  • -JPGN 2010; 51: 714. Use of MTX after thiopurines. n=27. 48% in remission at 6 months.
  • -JPGN 2009; 48: 526. Use in pediatric CD, n=25. 64% response
  • -JPGN 2009; 48 suppl 2: S111. MTX may be effective for UC.
  • -NEJM 2008; 359: 2790. Similar safety of AZA and MTX in vasculitis patients. AZA may be safer.
  • -IBD 2008; 14: 756. MTX in Crohn’s. n=39. 71% remission (20% steroid-free).
  • -J Clin Pharm & Therapeutics 2007; 32: 327-31.
  • -Am J Health Syst Pharm 2004; 61: 1380-84. review of MTX errors -FDA reported
  • http://www.npsa.nhs.uk/patientsafety/alerrts-and-directives/alerts/oral-methotrexate/
  • -Am J Gastro 2007; 102: 2804-2812. n=60 pediatric patients. ~42% in remission with MTX & ~50% improved. 13% (8) had to stop due to increased LFTs or sepsis.
  • -IBD 2006; 12: 1053. n=61. MTX for AZA nonresponders/breakthroughs: 80% with improvement/ 45% with long-term response; 10% discontinued due to side effects. Steroids stopped in 36.
  • -JPGN 2005; 40: 445. Oral MTX works as well as IM/SC.
  • -JPGN 2003; 37: 392 (194A) 0.4 mg/kg/weekly. 91% response at 2 mo, most still needed remicade
  • -Gastroenterology 2003; 124: suppl 1, A-41 (305) 11/12 responded – able to stop remicade
  • -Feagan et al. NEJM 1995; 332: 292-97.
  • -J Pediatr 1999: 134: 47. Hepatotoxic risk factors. (enzymes & obesity). Consider bx if serial enzymes increased >40% of the time over 1 year
  • -Arthritis Rheum 1997; 40: 2226.

Only one chance to make first impression

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

Top-down approach:

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.
**Much of the information on this posting was influenced by presentations at “Advances in IBD 2011.”  Specific speakers that influenced this posting include Robert Baldassano, Marla Dubinsky, and Miguel Regueiro.

Additional References:

  • 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.