Tag Archives: Crohn’s disease

NASPGHAN Pediatric Position Paper for Therapeutic Drug Monitoring

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LM Felipez et al. J Pediatr Gastroenterol Nutr. 2025;81:1100–1117. Open Access! North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition position paper on the therapeutic drug monitoring in pediatric inflammatory bowel disease

Therapeutic Drug Targets Based on Condition, Medication and Time of Therapy:

Discussion Points:

  • Pediatric Dosing is Different: “Pediatric studies have also determined adult infliximab targets are insufficient…In a prospective pediatric study, Clarkston et al. found that a trough level of 29 μg/mL at 2 weeks is required to achieve both clinical and biologic response. Patients with lower trough levels had 13-fold greater odds of clinical nonresponse. Additionally, a trough of 18 μg/mL at 6 weeks was associated with improved response. Patients with lower trough levels had sixfold greater odds of clinical nonresponse. They also observed that patients who did not achieve a trough >5–7 μg/mL by 14 weeks of therapy had a 21-fold increase in the odds of clinical nonresponse.62“
  • Undetectable/very low anti-TNF levels: “If the serum level is extremely low or undetectable, then full re-induction is warranted in addition to dose escalation.”
  • Timing of TDM: “As a practice point, TDM is routinely recommended at the end of induction for most patients. We recommend obtaining TDM earlier during induction in at-risk populations, including younger age children, those with hypoalbuminemia, and those with increased inflammatory burden.”
  • Maintenance proactive TDM: “Based on prospective randomized trial evidence, we recommend proactive TDM during maintenance every 6–12 months…yearly proactive TDM was associated with 55% reduced risk of developing antidrug antibodies.26“
  • Increased Antidrug Antibodies with Lower Infliximab Dosing: “In the pivotal REFINE study on immunogenicity in pediatric IBD, Coleman et al. found that antibodies to infliximab were detected in 68% of patients in the cohort, and starting dose under 7.5 mg/kg was one of the strongest predictors of developing antidrug antibodies.4“
  • Higher Doses Prevent Antidrug Antibodies: “The best available evidence for preventing immunogenicity supports initiating therapy with infliximab doses greater than 8 mg/kg, and in the case of hypoalbuminemia, doses greater than 10 mg/kg. For children <40 kg, doses of 200 mg/m2 are more appropriate.”
  • Perianal fistulas: “Overall, there is less evidence to support adalimumab use over infliximab for treatment of perianal fistulas. It is possible that adalimumab may have lower efficacy for perianal fistula.105 However, it is unclear if this is inherent to adalimumab, or if it relates to less frequent TDM or less frequent dose escalation in practice.”
  • Vedolizumab: “In general, as with other biologic therapies, a higher serum vedolizumab concentration is associated with higher likelihood of treatment response…Multiple studies identified that in patients with IBD (either UC or CD) early trough levels at Week 2132 with a cut off of >23.2 μg/mL or Week 6133, 134 with a cut off of above 22–28 μg/mL or at Week 14135) above 16.55 μg/mL predicted a higher likelihood of sustained response over the first year. In regard to clinical remission one study identified that corticosteroid free, clinical and biochemical remission was correlated to higher trough vedolizumab concentration.136“
  • Vedolizumab in younger patients: “Children under 30 kg require vedolizumab doses of 200 mg/m2 or 10 mg/kg.”

My take: “This NASPGHAN position paper should also serve to document that high-dose therapy, especially guided by TDM, is evidence-based standard of care.” This article clearly establishes three key points:

  1. “Intensive anti-TNF⍺ dosing strategies are not experimental. The initial doses of infliximab and adalimumab approved by the United States Food and Drug Administration (FDA) routinely lead to under-treatment, poor outcomes, and treatment discontinuation.60, 117 There is a rich, corroborated, and verified evidence-base to support the safety and efficacy of high-dose therapy anti-TNF⍺ therapy when clinically indicated, especially as supported by TDM.50, 62, 65, 100, 101, 103, 118“
  2. Therapeutic drug monitoring is essential in the pediatric population to optimize drug levels, allow many patients to do well with monotherapy, and to help avoid development of antidrug antibodies.
  3. The best available evidence supports TDM during induction of vedolizumab as well.

Related blog posts:

Disclaimer: This blog, gutsandgrowth, assumes no responsibility for any use or operation of any method, product, instruction, concept or idea contained in the material herein or for any injury or damage to persons or property (whether products liability, negligence or otherwise) resulting from such use or operation. These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  Because of rapid advances in the medical sciences, the gutsandgrowth blog cautions that independent verification should be made of diagnosis and drug dosages. The reader is solely responsible for the conduct of any suggested test or procedure.  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.

“Tasty & Healthy” Whole Food Diet For Crohn’s Disease

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Y Frutkoff et al. Gastroenterology 2025 (Article in Press). Open Access! Whole Food Diet Induces Remission in Children and Young Adults With Mild to Moderate Crohn’s Disease and Is More Tolerable Than Exclusive Enteral Nutrition: A Randomized Controlled Trial

Yesterday’s post (“A Practical Guide to Diet and IBD” (2025)) provided a summary of data on a multitude of diets for inflammatory bowel disease. Today’s post describes a study on a new diet, called the Tasty & Healthy diet.

Background: Tasty & Healthy (T&H) is a whole food diet for Crohn’s disease (CD) that excludes processed food, gluten, red meat, and dairy, without requiring formula or mandatory ingredients.

Tasty & Healthy (T&H) is an exclusive whole food diet, first published in a charity cookbook in 2014… The T&H diet was developed to reduce proinflammatory dietary exposures by excluding gluten, animal fat (ie, red meat and dairy, except for plain yogurt), as well as all processed food (anything that comes in a package except for those with 1 unprocessed ingredient.” (see details and supportive references in Supplementary Appendix 1).

Methods: TASTI-MM was a clinician-blinded, randomized controlled trial comparing tolerability and effectiveness of T&H (n=41) vs exclusive enteral nutrition (EEN, n=42). The intention to treat analysis included 83 patients (mean age 14.5 yrs, range 7-25 yrs).

Key findings:

  • 88% tolerated T&H vs 52% for EEN. 59% of the patients in the EEN arm did not complete the 8-week follow-up period, compared with only 15% in the T&H arm
  • Calprotectin, C-reactive protein, and erythrocyte sedimentation rate decreased significantly in both groups, with no between-group differences
  • Symptomatic remission was achieved in 56% of the T&H group vs 38% of the EEN group
  •  Calprotectin <250 μg/g was achieved in 34% T&H vs 33% of the EEN group
  • Microbiome α-diversity improved in the T&H arm and declined in the EEN arm, showing superior species richness at both week 4 and week 8. Species associated with bowel inflammation, such as Ruminococcus gnavus, decreased in T&H and increased in EEN (q < .001)

Discussion Points:

“In multiple studies CDED has been found to induce symptomatic remission in 62%–77% of patients with mild to moderate uncomplicated CD, including biologic remission in a subset of patients. Although conceptually similar to CDED in the exclusion of proinflammatory food
groups, the T&H diet differs in structure—requiring no formula and no mandatory components, thus offering greater dietary flexibility.”

“The T&H diet was tested across multiple international centers, while still achieving similar outcomes compared with EEN. The use of any exclusion diet requires guidance of a dietitian to ensure balanced nutrition, and this becomes even more important in diets when formula is not needed. Other exclusive whole food diets studied in the RCT setting are the Specific Carbohydrate Diet and Mediterranean diet, which were effective in inducing symptomatic remission, but demonstrated insufficient biologic remission rates.”

“In the past, dietary interventions have not been as widely adopted in adults as in children…Although EEN use has been hampered by the thought that adults will not tolerate nutritional interventions, the advent of whole food diets has changed that notion…In this study, we found that not only were the included adults adherent to the T&H diet, it was as effective as in children and treatment response was not associated with age.”

Related article: Plotkin L, Aharoni Y, Fenster D, et al. Tasty & Healthy is a
dietary approach for inducing and maintaining remission in Crohn’s disease: a prospective case series. United European Gastroenterol J 2021;9:521 (PO431).

My take: This “Tasty & Healthy” Diet appears to be an effective option for induction of remission for mild to moderate Crohn’s disease. Extended studies will be needed to help determine whether it could be used for longer duration in those with a response. Also, whoever labelled this diet initially clearly understands marketing as it sounds a lot better than EEN or CDED.

Related blog posts:

Disclaimer: This blog, gutsandgrowth, assumes no responsibility for any use or operation of any method, product, instruction, concept or idea contained in the material herein or for any injury or damage to persons or property (whether products liability, negligence or otherwise) resulting from such use or operation. These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  Because of rapid advances in the medical sciences, the gutsandgrowth blog cautions that independent verification should be made of diagnosis and drug dosages. The reader is solely responsible for the conduct of any suggested test or procedure.  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

Upadacitinib for Crohn’s Disease: U-ENDURE Study

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R Panaccione et al. Clin Gastroenterol Hepatol 2025; (In press) Open Access! Upadacitinib Maintenance Therapy in Crohn’s Disease: Final Results From the Randomized Phase 3 U-ENDURE Study

Methods: Clinical responders to 12 weeks of upadacitinib 45 mg once daily (QD) induction were randomized (1:1:1) to receive upadacitinib 15 mg QD (n = 221), upadacitinib 30 mg QD (n = 229), or placebo (n = 223) as maintenance therapy for 52 weeks

**This study presents data from the entire cohort (n=673); a previous report from ENDURE-3 analyzed data on 502 patients (though findings were nearly identical). EV Loftus et al. N Engl J Med 2023; 388:1966-1980 (Related post: Landmark Study: Oral Biologic for Crohn’s –Upadacitinib)

Key findings:

  • At week 52, more upadacitinib-treated vs placebo patients achieved CDAI clinical remission (upadacitinib 15 mg, 36.2% and upadacitinib 30 mg, 51.5% vs placebo, 15.2%)
  • The rates of endoscopic response were 27.3% for upadacitinib 15 mg and 40.7% for upadacitinib 30 mg vs 7.2% for placebo
  • Herpes zoster infections occurred more frequently in the upadacitinib groups compared with placebo; all were nonserious, and most involved a single dermatome
  • In U-ENDURE, no dose-dependent risk for MACE, VTE, or malignancy (excluding NMSC) was observed during the 52-week maintenance period

My take: Upadacitinib is a effective in a good number of patients with with moderately to severely active Crohn’s disease who have been refractory to other advanced therapies.

Related blog posts:

What Caught My Eye in a Recent Anti-IL23 Commentary

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This recent commentary on the all-subcutaneous induction and maintenance treatment with guselkumab, an anti-IL23 agent, reviewed the GRAVITI study. Related post: Guselkumab for Crohn’s Disease: Pivotal GRAVITI Study

However, what captured my attention was the last sentence: “The convenience of subcutaneous induction enhances patient friendliness, positioning guselkumab as a strong market contender. Could an oral anti–IL-23 formulation be the next game changer?14“

“Johnson & Johnson (NYSE: JNJ) today announced positive topline results from ANTHEM-UC, a Phase 2b study of icotrokinra (JNJ-2113), the first investigational targeted oral peptide that selectively blocks the IL-23 receptor, in adults with moderately to severely active ulcerative colitis (UC)…

In the ANTHEM-UC study (n=252), three doses of once daily icotrokinra were tested with all meeting the primary endpoint of clinical response at Week 12. A response rate of 63.5% for patients treated with the highest dose of icotrokinra was achieved at Week 12 versus 27% for placebo (p<0.001). Further, 30.2% of patients treated with the highest dose of icotrokinra demonstrated clinical remission at Week 12 versus 11.1% of patients who received placebo (p<0.01). Remission and response rates continued to improve through Week 28.

  • Clinical response is defined as decrease from baseline in the modified Mayo score by greater than or equal to (>=) 30 percent (%) and >=2 points, with either a >=1-point decrease from baseline in the rectal bleeding subscore or a rectal bleeding subscore of 0 or 1.
  • Clinical remission is defined as a Mayo stool frequency subscore of 0 or 1 and not increased from induction baseline, a Mayo rectal bleeding subscore of 0, and a Mayo endoscopy subscore of 0 or 1 with no friability present on the endoscopy.”

My take: It would be terrific for patients with inflammatory bowel disease (and other immune-mediated diseases) to have another excellent oral therapy. A prior study of plaque psoriasis indicated that an oral IL-23 medication is feasible (Related post: In Trials: An Oral IL-23 Antagonist Peptide).

Related joke (regarding “caught my eye” in the title of this post):

A man who lived in a block of apartments thought it was raining and put his head out the window to check.  As he did so a glass eye fell into his hand. He looked up to see where it came from in time to see a young woman looking down. “Is this yours?” he asked.

She said, “Yes, could you bring it up?” and the man agreed. On arrival she was profuse in her thanks and offered the man a drink. Shortly afterwards she said, “I’m about to have dinner.  There’s plenty; would you like to join me?” He readily accepted her offer and both enjoyed a lovely meal. As the evening was drawing to a close the lady said, “I’ve had a marvelous evening.  Would you like to stay the night?”  The man hesitated then said, “Do you act like this with every man you meet?”

“No,” she replied, “only those who catch my eye.”

The Manneporte by Claude Monet (at the Metropolitan Museum of Art)

Are We Giving the Right Advice on Sunlight?

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I was recently listening to a radio program (On Point) about the beneficial effects of sunlight.

The program notes that the potential beneficial effects of sunlight are much greater than the risks. Increased sunlight has been associated with lower rates of death, as well as lower rates of cardiovascular disease and autoimmune conditions like multiple sclerosis, type 1 diabetes, and Crohn’s disease.

When dermatologists recommend avoiding sunlight, they may be focused on the risks but not the benefits (though this varies among individuals). In addition, despite the more than 5-fold rise of melanoma diagnosis (especially in wealthy communities), there has not been a change in the rate of deaths due to melanoma. Skin cancers associated with sun exposure are mainly basal cell tumors and squamous cell tumors. These non-melanoma skin cancers have excellent survival rates.

Here is a link: The Healing Power of Sunlight (48 minutes) The most important part of this is in the middle, starting around 20 minutes.

My take: It’s a good idea to avoid sunburns but getting sunshine is good for health.

Related article:

  • Environ Epidemiol 2025. 9(3):e401. doi: 10.1097/EE9.0000000000000401. The association between time spent outdoors during daylight and mortality among participants of the Adventist Health Study 2 Cohort. Conclusion: “Moderate time outdoors in daylight during warmer months could be associated with lower risks of all-cause, CVD, and noncancer non-CVD mortality”

Related blog posts:

River Cherwell in Oxford, UK
Oxford Botanic Garden

Guselkumab for Crohn’s Disease: GALAXI-2 and GALAXI-3: 48-Week Results

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R Panaccione et al. The Lancet. Published online July 17, 2025 https://doi.org/10.1016/S0140-6736(25)00681-6. Efficacy and safety of intravenous induction and subcutaneous maintenance therapy with guselkumab for patients with Crohn’s disease (GALAXI-2 and GALAXI-3): 48-week results from two phase 3, randomised, placebo and active comparator-controlled, double-blind, triple-dummy trials

Methods: “GALAXI-2 and GALAXI-3 were identically designed, phase 3, randomised, double-blind, triple-dummy, treat-through trials with active and placebo comparators…1048 participants were randomly assigned, treated, and followed up until week 48, of whom 1021 participants were included in the primary analysis population: 508 (49·8%) in GALAXI-2 and 513 (50·2%) in GALAXI-3.” The studies enrolled adult patients with moderately to severely active Crohn’s disease.

Key findings:

Discussion points:

  • “Guselkumab treatment in participants with moderately to severely active Crohn’s disease was also evaluated in the GRAVITI study, which had a fully subcutaneous induction and maintenance treatment regimen. Clinical and endoscopic outcomes reported with subcutaneous guselkumab induction in the GRAVITI study were similar to those in the phase 3 GALAXI studies following intravenous guselkumab induction.”
  • “The incidence of adverse events with guselkumab during induction was low and similar to placebo.”

My take (borrowed from authors): In GALAXI-2 and GALAXI-3, both guselkumab dose regimens (each including intravenous induction and subcutaneous maintenance) were superior to placebo for short-term (week 12) and long-term (week 48) endpoints and both guselkumab dose regimens were also superior to ustekinumab

Related blog posts:

Understanding the Prevalence and Burden of Pediatric Inflammatory Bowel Disease in U.S.

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 From editorial (which is more expansive than the study):

Kappelman et al4 report the US prevalence of pediatric-onset IBD (diagnosed before the age of 20 years by a physician) as well as rates of disease based on race and ethnic background. To ensure that a representative population was captured, they combined multiple health administrative databases…

The authors report that the US currently has a pediatric IBD prevalence of 125 per 100,000 population, increased from 110 per 100,000 in 2011. This is higher than previously reported in Canada (82 per 100,000 in 2023)6 and Sweden (75 per 100,000 in 2010).7 These differences may be due to the older age cutoff used in the US data, <20 years vs <18 years in the Canadian and Swedish studies. However, misclassification bias may also play a role...

Nevertheless, understanding the approximate prevalence of pediatric IBD in the US allows for adequate human and financial resource planning for this important population of children with an impactful chronic disease. The high prevalence should raise concerns among health care practitioners and policy makers that we have under-resourced IBD care in children, especially considering the high rate of use of biologics and the growing direct health costs incurred in the treatment of this population.11

The burden of IBD in pediatrics goes beyond that of the child. Compared with adult IBD, it disproportionately affects caregivers and families (owing to missed work for appointments, hospitalizations, and home care), mental health of both the patient and the parents, and the health system...

They report that pediatric IBD is more frequent among White children and adolescents (145 per 100,000) compared with Black (91 per 100,000) and Hispanic (88 per 100,000) children, whereas children of Asian origin have markedly lower rates (52 per 100,000).“

My take: The updated prevalence data helps understand the increasing frequency of pediatric IBD. The associated commentary reminds us of the broader burden the disease has for families and for our communities.

Related blog posts:

Constipation Preceding a New Diagnosis of Inflammatory Bowel Disease

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S Cenni et al. J Pediatr Gastroenterol Nutr. 2025;80:799–806. The prevalence of constipation in children with new diagnosis of inflammatory bowel disease: A retrospective study

This was a cross-sectional observational study in pediatric IBD-patients (n=238) with 104 (43.6%) with Crohn disease (CD), 130 (54.6%) with ulcerative colitis (UC) and 4 (1.6%). Only patients who filled out the Rome IV questionnaire for FC, through dedicated symptom recall at the next clinic appointment or telephone recall, were finally enrolled in the study for subsequent analysis.

Key findings:

  • Forty-seven out of 238 (19.7%) had a functional constipation history before the IBD diagnosis. In the CD children the prevalence of constipation before the IBD diagnosis was 19/104 (18.2%) and in the UC patients was 28/130 (21.5%).
  • The difference in terms of endoscopic localization was statistically significant in UC patients presenting FC (p = 0.026) with a prevalence of proctitis and left side colitis (30% and 15%, respectively)
  • There was a delay in the diagnosis of patients with preceding constipation

Discussion Points:

  • The main limitations of the present study are certainly related to the retrospective nature and, therefore, the possibility of recall biases must be taken into account.
  • Rectal bleeding that persists despite stool softener therapy should be investigated

My take: While this study shows that constipation is fairly common prior to a diagnosis of IBD, many times a parent is told that their child is constipated on the basis of an xray or simply because the child complained of stomach pain. This likely increases the risk of recall bias. My guess is that a prospective study involving careful questioning at the time of the initial colonoscopy would yield a lower number of children who had constipation at the time of diagnosis.

Related blog posts:

Set of Shucked! at The Fox Theater. Really enjoyed this ‘corny’ musical.

Mediterranean Diet’s Impact on Crohn’s Disease Outcomes

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Methods: In this prospective cohort study, consecutive adults (n=271) from 2 large IBD centers in Israel with newly diagnosed CD were recruited and followed prospectively. MED adherence was assessed by repeated food frequency questionnaires (FFQs) using a predefined inflammatory bowel disease Mediterranean diet score (IBDMED score), alongside validated MED adherence screeners. Crohn’s disease activity index (CDAI), C-reactive protein, fecal calprotectin, and microbial composition (16S-ribosomal RNA sequencing) were assessed each visit. Baseline serum and fecal samples were analyzed for targeted quantitative metabolomics.

Demographic/Clinical data indicate 68% received biologics and 40% receiving immunomodulators. 32% received 5-ASA medications (despite lack of proven efficacy)

Key findings:

  • Adherence to MED was associated with a noncomplicated CD course, and inversely correlated with CDAI, fecal calprotectin, C-reactive protein, and microbial dysbiosis index (all P < .05)
  • Increasing adherence to MED over time correlated with reduced CDAI and inflammatory markers (P < .05)
  • Adherence to MED correlated with a beneficial microbial cluster of commensals and short-chain fatty acid producers including Faecalibacterium, and with plant metabolites, vitamin derivatives, and amino acids 
  • Adherence to MED in the cohort group was comparable to the general non-IBD population in Israel

Limitations: This was an observational study rather than an interventional study with a control group. Thus, the results could be influenced by reverse causality

In the associated commentary by Abreu et al, it is noted that in Israel, “MED is more commonplace than in the US and other Western countries…Godny et al found that IBD patients had an average MED adherence score of 7.8, which is similar to that of the general non-IBD population in Israel; in contrast, the average MED adherence score in the US is 4–5.Godny et al’s CD patients consumed an average of 21 g of fiber per day; in a study we just completed, American CD patients consumed less than half that amount.13 Indeed, the baseline diets of American IBD patients are characterized by high amounts of saturated animal fat and almost no fresh fruits and vegetables…Another difference between the Israeli population and the typical American population is body mass index (BMI). The average BMI of patients in this study was 21.9 kg/m2 (interquartile range 20–25.3 kg/m2). This contrasts with the average BMI of the general US population of 30 kg/m2.”

My take: This study shows an association between MED diet and better outcomes/less complications in adults with Crohn’s disease. Eating a good diet is an important part of treatment.

Additional notes on dietary scores: “The IBDMED screener positively scored high consumption of MED-recommended dietary components such as fruits, vegetables, olive oil, legumes, nuts and seeds, and fish. It also positively scored low consumption of MED non-recommended dietary components such as red and processed meat, soft drinks, and sweets. To this we added several dietary features based on previous data associated with microbial composition and function. These included a positive score for plant diversity27 by scoring for different colors in the diet, consumption of fermented foods28 (specifically yogurt), and inclusion of starchy vegetables like potato in the whole grain category to promote diversity in the carbohydrate-rich food group, as well as support butyrate producers as we had previously shown.29 In addition, we aimed to positively score for relatively low UPF intake. To this end, we evaluated the average intake of sweets, snacks, sweet and savory pastries, soft drinks, and foods and drinks containing artificial sweeteners.”

Related blog posts:

Also, from Kim Beall, Cofounder and Managing Director of Nutritional Therapy for IBD:

“If you haven’t been to the website recently, we have expanded the recipe database to over 1,000 recipes with many filterable aspects and we’ve just released a new nutrition tool, the IBD Nutrition Navigator to facilitate nutrition conversations between providers and patients to find the right nutritional starting point. This is a project led by Dr. Ananthakrishnan and a dedicated team of pediatric and adult medical advisors in a two year long development process. Many have told us this is a useful tool particularly for those less familiar with nutrition in IBD. We’re excited about it’s potential to integrate nutrition in practice, with “an option for every patient”. We appreciate your support in sharing our information, tools, and resources to advance IBD nutrition care.” Here’s the link to their website:

How HLA DQA1*05 and Combination Therapy Modulate Treatment Outcomes in Children with Crohn’s Disease

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J Adler et al. Am J Gastroenterol 2025; 120: 1076-1086. HLA DQA1*05 and Risk of Antitumor Necrosis Factor Treatment Failure and Anti-Drug Antibody Development in Children’s with Crohn’s Disease.

This was a prospective, double-blind, placebo-controlled trial with 204 patients examining the clinical outcomes of anti-TNF with or without methotrexate (COMBINE).

Key findings:

  • Treatment failure in HLA DQA1*O5: A trend toward increased treatment failure among HLA DQA1*05-positive participants was not statistically-significant (hazard ratio 1.58; P = 0.08).
  • HLA DQA1*05 and Treatment Failure Rate: During the followup period, HLA DQA1*05-positive patients had a 35% failure rate compared to 26% for those who were HLA DQA1*05-negative (P=0.098). The overall failure rate was 30%
  • Methotrexate Combined with HLA DQA1*05 Effect: Patients who were HLA DQA1*05 negative and assigned to methotrexate experienced less treatment failures than HLA DQA1*05-positive patients on placebo (hazard ratio 0.31, 95% CI 0.13-0.70; P = 0.005).
  • Anti-TNF Medication Comparison: Treatment failure was similar between infliximab and adalimumab, 29% and 33% respectively
  • Antidrug antibodies (ADA): A trend toward increased ADA development among HLA DQA1*05-positive participants was not significant (odds ratio 1.96, P = 0.09). The addition of methotrexate to the treatment regimen mitigated the risk of treatment failure among individuals positive for HLA DQA1*05 and reduced the odds of developing ADA by 90%.
  • Rate of ADA: “After further stratification, HLA DQA1*05-negative participants assigned to methotrexate were less likely to develop ADA relative to HLA DQA1*05-positive patients on placebo (odds ratio 0.12; P = 0.008).”

Discussion Points:

  • “A retrospective by Fuentes-Valenzuela et al …found that if patients underwent proactive TDM, there was no increase in the rate of treatment discontinuation among those who were HLA DQ-A105 positive compared with HLA DQ-A105 negative”
  • “The totality of evidence suggests that HLA DQ-A1*05 seems to confer a risk of both immunogenicity and treatment failure, particularly among infliximab-treated patients. Furthermore, this risk may be mitigated by the use of proactive TDM and/or concomitant immunomodulators.”

My take (borrowed in part from authors):  “40% of patients were HLA DQ-A1*05 positive, which was associated with a trend toward increased risk of both treatment failure and ADA. These risks were mitigated, but not eliminated, by adding oral methotrexate.” The use of combination therapy (methotrexate with anti-TNF) was associated with the lowest failure rates.

Also, unrelated article: DA Carlson et al. Gastroenterology 2025; 168: 1114-1127. A Standardized Approach to Performing and Interpreting Functional Lumen Imaging Probe Panometry for Esophageal Motility Disorders: The Dallas Consensus. Congratulations to Dr. Garza from our group who was one of the authors

Related blog posts: