Three Studies Show Benefit of Concomitant Therapy for Inflammatory Bowel Disease (Part 1)

In the first study (J Cheng et al. Inflamm Bowel Dis 2017; 23: 1762-73), the authors retrospectively reviewed 148 children (113 with Crohn’s disease, 35 with ulcerative colitis). 90 patients received concomitant therapy (infliximab with either a thiopurine [n=67], methotrexate [n=23]) and 58 received infliximab monotherapy. Key findings:

  • Concomitant therapy >6 months  significantly lowered the risk of secondary loss of response in Crohn’s disease (CD) (HR =0.39) compared to monotherapy.   A similar trend was noted with ulcerative colitis (UC) but did not reach statistical significance.
  • Steroid-free remission rates at 1 year were 78% for CD patients with concomitant therapy compared with 54% on monotherapy
  • Among primary nonresponders, 67% of CD patients and 75% of UC patients were receiving IFX monotherapy.
  • No differences in adverse events were evident between patients receiving monotherapy compared with concomitant therapy. One patient (receiving azathioprine) developed a follicular lymphoma; this patient was well 10 years later.

The second study (Y Qui et al. Clin Gastroenterol Hepatol 2017; 15: 1359-72) was a systemic review of 35 studies that met the authors’ inclusion criteria. In total, 6790 patients with inflammatory bowel disease were enrolled in these studies. This study looked at multiple anit-TNF agents including infliximab, adalimumab, certolizumab, and golimumab. Key finding:

  • Antidrug antibodies were reduced by 51% in patients receiving concomitant therapy
  • Conclusion from authors: “concomitant use of immunomodulators should be considered in patients treated with anti-TNF treatment.”

My take: Overall, for most pediatric patients with CD, to date, concomitant therapy has been the most effective treatment.  More prospective studies are needed to determine more conclusively the benefit and optimal duration/timing of combined therapy, particularly with the more frequent use of therapeutic drug monitoring.  Also, as will be noted in future posts from annual meeting, thiopurine use is declining.

More on this topic tomorrow.

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Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

Support for Step-Up Therapy and Thiopurines

A retrospective study (H Bar-Yoseph et al. Clin Gastroenterol Hepatol 2017; 15: 69-75) indicated that thiopurine use before infliximab (IFX) was associated with the prevention of antidrug antibody formation in patients with Crohn’s disease.

The authors had 207 eligible patients which included 93 who received IFX monotherapy, 52 who received combination therapy after response to thiopurine, 34 who received IFX after lack of response to thiopurines (but continued with combination treatment), and 28 who received de novo combination therapy.  The total number of patients followed in these centers is much higher, but they excluded those with episodic infusions and for other reasons that could affect their conclusions.

Key findings:

  • Prior thiopurine therapy was associated with lower antidrug antibodies (ADA). At 1 year, past thiopurine responders had 19.3% ADA, past thiopurine failures had 16.1% ADA; both were much lower that the monotherapy rate of 46.6%  The de novo combination group had a rate of 21.9% which did not reach significance.
  • Interestingly, after the first 5 months, the de novo combination group did not develop further ADA but during the first 5 months the rate of ADA was quite similar to the monotherapy rate. This could be related to the notion that thiopurines may take 3-6 months to achieve full effect.
  • Combination therapy (compiled)  was associated with higher rates of clinical remission (58.8% vs 40.9%) and lower rates of active disease (8.8% vs. 21.5%).

Overall, this study showed high rates of ADA compared to many studies but the conclusions are similar to other published studies.  It could be that many of those with positive ADA were lower antibody levels and that many of these levels may not be clinically significant. The study has limitations mainly related to being a retrospective study.

My take: This study supports the following:

  1. Combination therapy is more effective than monotherapy
  2. Using an immunomodulator before starting infliximab may reduce ADA formation more effectively than starting combination therapy de novo.

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Disclaimer: These blog posts are for educational purposes only. Specific dosing/usage of medications (along with potential adverse effects) should be confirmed by prescribing physician.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

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Changes in the Use of IBD Biologic Therapy

A recent study (W-J Lee et al. Inflamm Bowel Dis 2016; 22: 2410-17) offers a great deal of insight into changes in the use anti-Tumor Necrosis Factor Alpha (ant-TNF) therapy from 2009-2013 in patients ≤24 years.  The authors utilized databases with about 180 million people and identified 11,962 patients with inflammatory bowel disease (IBD).

Key findings:

  • 3300 of the 11,962 (27.6%) patients were treated with anti-TNF therapy.
  • Top-down treatment: 1298 of 3300 (39.3%) were treated with top-down therapy which was defined as usage of anti-TNF therapy within 30 days of first IBD medication prescription.  Interestingly, over the course of the study, there was a trend towards more top-down (versus step-up) therapy and shorter time to initiation of anti-TNF therapy. In 2009, 31.4% used a top-down approach compared with 49.8% in 2013.
  • Top-down therapy is associated with lower rates of corticosteroid use.
  • Infliximab dominant anti-TNF: infliximab was the anti-TNF in 89.2% of patients less than 12, 82.3% of patients 12-17, and 55.1% of patients 18-24.  Adalimumab accounted for the vast majority of the other TNF users. Though, the authors note a trend towards increasing use of adalimumab in both adult and pediatric patients in a separate study (Park KT et al. Inflamm Bowel Dis 2014; 20: 1242-49)
  • Cotherapy: thiopurines and methotrexate were used as cotherapy in 13.5% and 7.2% of top-down group compared with 54.8% and 14.6% respectively in step-up strategy.
  • Drug therapy among non-TNF users: 25.4% (2199) received a thiopurine, 79.3% (6871) received a 5-aminosalicylate, and 2.3% (201) received methotrexate.
  • Anti-TNF therapy discontinuation: Using top-down strategy 69.2% persisted on infliximab at 12 months and 56.8% persisted at 24 months.  In comparison, using step-up approach with infliximab, it was 72.7% at 12 months and 64.0% at 24 months.  The numbers were quite similar with all the anti-TNF agents indicating that step-up approach had significantly lower rate of anti-TNF discontinuation. The authors speculate that one factor could be use of cotherapy or possibly other adverse reactions.

The authors explain some of the limitations of their study in its reliance on databases, particularly with regard to misclassification.  However, in my opinion, these limitations do not affect any of the trends that the authors are able to document.

My take: For most of my patients, I have preferred to continue to utilize cotherapy  and/or step-up therapy because I think there is likely to be a more durable anti-TNF response.  The fairly small differences in anti-TNF durability have huge implications for those  who lose anti-TNF responsiveness given the limited treatment options.

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Optimal Dose of Thiopurine When Used for Combination Therapy

To improve long-term outcomes and response in patients with inflammatory bowel disease, many experts advocate the use of combination therapy (thiopurine with anti-tumor necrosis factor).  Thiopurine cotherapy resulted in higher response rates in pivotal studies (eg. SONIC, UC Success), likely due to lower rates of antidrug antibody (ADA) and higher serum levels of biologic agents (e.g. infliximab).  To achieve these advantages, it is not clear whether a lower dose of a thiopurine may be similarly effective as a higher dose.  If a lower dose could result in a similar effect, it would likely result in fewer adverse effects.

A recent study (Yarur AJ, et al. Clin Gastroenterol Hepatol 2015; 13: 1118-24) provide some data to address the issue of optimal dosing of thiopurines.  The authors performed a cross-sectional study of 72 patients receiving infliximab (IFX) and a thiopurine.

Key findings:

  • The thiopurine metabolite 6-thioguanine (6-TG) that “best predicted a higher level of infliximab was 125 pmol/8 x 10 to the 8th RBCs.”
  • Only 8 patients (11%) had detectable antibodies to infliximab (ATI)
  • Patients with 6-TG <125 were more likely to have ATI (OR 1.3)
  • Higher 6-TG levels did not confer additional benefit

This study had many limitations including the small number of patients and the cross sectional design.  In addition, the patients may not be representative of typical patients; more than 50% were in endoscopic remission. A randomized controlled trial with larger number of patients is needed for a more definitive answer.

Take-home message: (from authors); “6-TGN metabolite levels rather than weight-based dosing may assist clinicians in optimizing treatment when using thiopurines in combination with IFX…lower target 6-TGN levels (125-176 pmol/8 x 10 to the 8th RBCs) may be adequate to maximize IFX levels and reduce immunogenicity while potentially minimizing toxicity.”

Briefly noted:

Ananthakrishnan AN et al. Clin Gastroenterol Hepatol 2015; 13: 1197-1200.  In this prospective study with 1659 patients with Crohn’s disease (CD) and 946 patients with ulcerative colitis, the authors found wide variation among the 7 participating academic centers, particularly with regard to CD treatment.  Comparing the site with the lowest usage to the highest usage, for CD:

  • Oral mesalamine 13% vs. 46%
  • Immunomodulator use 16% vs. 56%
  • Anti-TNF use 31% vs 60%
  • Combination therapy 8% vs 32%
  • Immunomodulator-naive anti-TNF use 10% vs. 17%
  • Surgery 32% vs 55%

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Why ImproveCareNow is Needed

A few recent articles make a strong argument for collaborative networks, like ImproveCareNow, to improve data collection to determine the most effective therapies.

  1. Kierkus J, et al. JPGN 2015; 60: 580-85.
  2. Audu GK, et al. JPGN 2015; 60: 586-91
  3. Dotson JL, et al. Inflamm Bowel Dis 2015; 21: 1109-14
  4. Saps M, et al. JPGN 2015; 60: 645-53.

A brief description of each study.

1. This study presented a multi-center randomized open-label trial of 99 pediatric patients with Crohn’s disease (CD) who were administered infliximab (IFX) along with an immunomodulator (azathioprine or methotrexate).  After a 10 week induction, 84 were randomized to either monotherapy for 54 weeks or dual therapy for 26 weeks. The authors did not find significant differences in response between the groups.  However, they reached a conclusion: “Twenty-six weeks likely represent (sic) the safe duration of combined IFX/immunomodulator therapy in our sample of pediatric patients with CD.”

2. The second study described three cases of chronic recurrent multifocal ostesomyelitis (CRMO) associated with inflammatory bowel disease.  They tried to identify all pediatric cases in UK in the last 10 years. (As an aside, I have treated one teenager with CRMO and ulcerative colitis.)

3. The third study is a retrospective single center of 30 patients with pediatric Crohn’s disease (CD) who developed intra-abdominal abscesses (IAA) over a 12-year period.  The authors note that this is “the largest single-center review of children and adolescents with CD and IAA to date.” Yet due to the small sample size, the study provides little guidance on this important medical problem; there were no predictors of successful medical or percutaneous drainage therapy.  In addition, with the increasing use of biologics, the authors note that “the issue of which patients will eventually require surgery is even less clear.” Changes in imaging (eg. MRE) and changes in medical management (eg. more enteral nutrition and less corticosteroids) are not discussed.

4. The fourth study is a comprehensive review of randomized placebo-controlled pharmacological clinical trials in children with functional abdominal pain disorders.  They found “no evidence to support the use of most commonly used drugs in children. Only 7 pharmacological RCTs on AP-FGIDs in children were found. Most studies were single center based and had a small sample size.  The methods and outcomes were heterogeneous…We found a considerable risk of bias in most studies…There is an urgent need for well-designed randomized clinical trials using age-appropriate validated outcome measures.”

Each of these studies makes a compelling argument for collaborative research networks.  The first study had a relatively small number of patients, short follow-up period, lack of blinding, and numerous methodological limitations.  How did the authors determine that 26 weeks was the time to stop dual therapy? Among adults with CD, a well-designed SONIC study (NEJM 2010; 362: 1383) showed the superiority of dual therapy during the study period.  In children, because of concerns about thiopurine safety, the best approach is still unclear. The second study identified only three patients despite examining a large population.  Similarly, the third study describes 30 patients with a common complication of CD but provides little insight.

The fourth study is a cautionary tale illustrating the lack of progress due to the absence of collaborative research.  Reports indicate a high prevalence of functional abdominal pain; one study indicated that abdominal pain affects “38% of school children weekly” (J Pediatr 2009; 154: 322-6).  In fact, studies on the high prevalence of this disorder dates back for 60 years (Apley, 1975; Apley & Hale, 1973; Apley & Naish, 1958). Despite the prevalence of this problem, the data for all of the treatments is poor.  The lack of progress in defining treatments for functional abdominal pain is multifactorial, including the following:

  • Cost: For many of the available treatments, there is not a financial incentive to conduct research.
  • Biomarker: lack of objective markers for improvement
  • Disease Stigma: many people attribute functional disorders as being due solely to psychological factors
  • Physician Champions: in pediatric gastroenterology, it took concerted physician efforts over many years to develop ImproveCareNow.  Similar physician champions would be needed to improve the outcomes for children with functional disorders

Bottomline: While ImproveCareNow has a lot of work ahead including improving data reliability and ascertaining accurate outcome measures, I think the effort is forward-thinking and will make a difference in understanding and treating children with IBD.  ImproveCareNow has more than 600 participating pediatric gastroenterologists and more than 20,000 patients. What I would like to see is a sister network to address the morbidity from functional disorders so that in 60 years (or sooner), we will be better equipped to treat children with abdominal pain that is not due to IBD.

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Drug levels for inflammatory bowel disease

In many conditions, drug levels are helpful to make sure the patient receives an adequate dose for the indication.  When we treat infections or seizures, drug levels predict the effectiveness of the medication and allow dosing adjustments to improve responses as well as to lower toxicity. Drug levels are helpful in inflammatory bowel disease (IBD) as well.  Drug levels may help with thiopurine dosing and with infliximab (IFX) dosing.

Infliximab (IFX) levels can guide therapy (Scand J Gastroeneterol 2011; 46: 310-18). This study examined 106 patients (85 with CD and 21 with UC) over a ten-year period. In this cohort, patients received concurrent hydrocortisone, acetaminophen, and cetirizine to prevent acute reactions and to try to limit anti-infliximab antibodies (ATI), also called anti-human antichimeric antibodies (HACA).  Infusion intervals ranged from 4-12 weeks.

69% of Crohn’s patients maintained response to IFX and 48% of UC patients.  Infliximab trough levels were significantly increased among patients who maintained their response.  A cutoff value of 0.5 μg/mL was defined as clinically relevant for IFX trough concentrations for Crohn’s patients and for UC the cutoff was 0.8 μg/mL .  Trough levels below this cutoff were 86% sensitive and 85% specific for identifying loss of response.  The overall accuracy for the test was 87% in identifying loss of response.

Also, ATIs were significantly higher in CD patients who had lost response to infliximab.  Patients who had been “re-treated,” were significantly more likely to have developed ATIs.  “Re-treated” was defined as having interruption of IFX treatment more than 6 months.

These specific cutoff values apply to the radioimmunoassay technique for measuring IFX and ATI.  These values may not extrapolate to ELISA assays.  At the same time, the findings suggest a practical approach in patients with symptoms while receiving IFX:

  • Check IFX level (at trough or at 4 weeks)
  • If low level and no ATI, likely to respond to dose escalation
  • If low level but positive for ATI, not likely to respond to dose escalation
  • Do not assume symptoms are due to drug failure; reassess with imaging &/or scope. Consider alternate etiologies (eg infections, stricture, celiac, IBS).
  • Cotherapy with an immunomodulator reduces ATIs and boosts levels of IFX.
More usage of IFX and ATI levels is likely; however, cost issues preclude frequent measurements.

Additional references:

  • Only one chance to make first impression.  Previous blog entry on use of infliximab.
  • -Clin Gastro & Hepatology 2011; 9: 395. Do not assume symptoms are due to drug failure -reassess with imaging &/or scope. Consider alternate etiologies (eg infections, stricture, celiac, IBS). Check IFX level –if >12 @ 4weeks or >1.4 mcg/mL at trough –>predicts good response.  If +HACA, ~90% response with alternative TNF.  In those with low level, 86% responded to dose escalation.
  • -DDW 2011, Abstract #772. If loss of response to IFX, **confirm active dz (labs, scope) & not due to CDT. **check HACA –if +, only 10-20% chance of responding to dose escalation; better chance of responding to similar agent **check IFX week 4 level, if low (& neg HACA) then 90% respond to dose escalation
  • -NEJM 2010; 362:1383-1395. SONIC study.  Patients with moderate-to-severe Crohn’s disease who were treated with infliximab plus azathioprine or infliximab monotherapy were more likely to have a corticosteroid-free clinical remission than those receiving azathioprine monotherapy.
  • -Gut 2010; 59: 49-54. Trough IFX levels in UC. n=115. Antibody status can only be measured at trough levels. Undetectable trough level (<1.4 mcg/mL) associated with lower remission (15% vs 69%) and lower endoscopic response (28% vs 76%) & higher colectomy rate (55% vs. 7%).
  • -Gastroenterology 2010; 139: 344 (review of above Gut article). Similar to Crohn’s disease: 82% remission with detectable trough vs 6% w/o detectable level.
  • Lancet 354 (9194): 1932–9. doi:10.1016/S0140-6736(99)05246-0PMID 10622295.”Infliximab (chimeric anti-tumour necrosis factor alpha monoclonal antibody) versus placebo in rheumatoid arthritis patients receiving concomitant methotrexate: a randomised phase III trial. ATTRACT Study Group”.
  • -Am J Gastroenterol 2010; 105: 1133-39. If lack/loss of response, may need dose escalation with humira or Cimzia (q2weeks):
  • -IBD 2011; 17: 141-51. Loss of response to biologics.
  • -Gastro & Hep 2008; 4: 12. “primary nonresponse can be determined after 2 doses” in table reiterating AGA consensus guidelines. 85% of responders show benefit by 2weeks & all responders benefit c/in 6 weeks (Am J Gastro 2001; 96: S303). Worsening Sx despite infliximab indicates need to look for stricture, infxn, etc.
  • -Clin Gastro & Hep 2006; 4: 1248. Clinical remission associated with measurable infliximab troughs; thus, if no measurable trough, increase dose or shorten interval. If level detected & no response, unlikely to respnd to TNF class. Also, concurrent immunomodulators were not helpful.
  • -Am J Gastro 2010; 105: 2617 (Oussalah et al). 2-3yrs 41% IFX failure in UC. withdrawal of AZA increase loss of response –7x more likely
  • -Am J Gastro ; 105: 1133-40. n=155. 23% ATI -92% respond to med change, 17% respond to dose change. Level <12 @ 4weeks, 86% respond to dose change
  • -Gut 2010; 59: 1363. n=121. Co-treatment helped reduce complications & flares relative to monotherapy (& azathioprine appeared to be more effective than methotrexate).

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.