IBD & Intestinal Disorders

In a rapidly expanding therapeutic landscape, the American Gastroenterological Association (AGA) has issued updated practice guidelines for the pharmacological management of moderate to severe ulcerative colitis (UC) in adult outpatients.

“These are the first living guidelines published by a GI society, highlighting the interest and need to provide timely guidance to all stakeholders in a rapidly evolving field,” first author Siddharth Singh, MD, of the Division of Gastroenterology in the Department of Medicine at University of California, San Diego, said in an interview. Living guidance allows for ongoing revision of individual recommendations as new data emerge. Nearly 2 million Americans have UC.

 

Issued in Gastroenterology and updating the last guidance in 2020, the recommendations suggest more efficacious drugs should be used sooner. “Early use of advanced therapies including biologics and small-molecule drugs are more effective than 5-aminosalicylates [5-ASAs] or thiopurines and methotrexate for most patients with moderate to severe UC and those with poor prognostic factors,” coauthor and gastroenterologist Manasi Agrawal, MD, MS, an assistant professor of medicine at Icahn School of Medicine at Mount Sinai in New York City, said in an interview.

“We provide a practical guidance based on best-available evidence to make it easy for the treating clinician to make informed choices from the multiplicity of available treatments for UC,” added guidelines coauthor Ashwin Ananthakrishnan, MBBS, MPH, AGAF, a gastroenterologist at Massachusetts General Hospital in Boston.

 

The comprehensive, patient-centered document comes with this caveat from the AGA panel: “These guidelines are meant to be broad recommendations for management of patients with moderate to severe UC and are not intended to address the intricacies of individual patients,” they wrote. “Provider experience and patient values and preferences can inform treating providers and patients to reasonably choose alternative treatment options.”

One gastroenterologist who has been eagerly awaiting these guidelines but not involved in the panel is James D. Lewis, MD, MSCE, AGAF, a professor of medicine and epidemiology at Perelman School of Medicine at the University of Pennsylvania, Philadelphia. “The choice of medications for moderately to severely active UC has expanded tremendously in the past few years,” he said in an interview. “This resulted in the dismantling of the historical therapeutic pyramid.” And while there are many more treatment options, knowing which medication to use for which patient and in which sequence has become much more complicated. 

“These guidelines will be extremely helpful for clinicians trying to navigate this new era of UC care,” he said.

The guidelines also outline implementation considerations for optimal use in different scenarios. “Key considerations include patient-related factors such as age, frailty, other health conditions, consideration for pregnancy, patient preferences, and access to healthcare,” Agrawal said.

 

Specifics

Overall, the guidance recommends advanced or immunomodulatory therapy after failure of 5-ASAs rather than a step-up approach. Moderate to severe disease is defined as a Mayo endoscopic severity subscore of 2 or 3.

The recommendation may also apply to mild disease in the presence of a high burden of inflammation and a poor prognosis or steroid dependence or resistance.

The AGA guideline panelists took account of differences in treatment efficacy between drugs within the same therapeutic class and made their recommendations by specific drugs rather than therapy class.

Based on varying degrees of evidence certainty, the AGA recommends or suggests the following management specifics in adult outpatients with moderate to severe disease:

• Any of the following is recommended over no treatment: infliximab (Remicade), golimumab (Simponi), vedolizumab (Entyvio), tofacitinib (Xeljanz), upadacitinib (Rinvoq), ustekinumab (Stelara), ozanimod (Zeposia), etrasimod (Velsipity), risankizumab (Skyrizi), and guselkumab (Tremfya).
• Adalimumab (Humira), filgotinib (Jyseleca), and mirikizumab (Omvoh) are suggested over no treatment.
• Biosimilars to infliximab, adalimumab, and ustekinumab can be considered of equivalent efficacy to their originator drugs.
• For patients naive to advanced therapies, the AGA panel proposes using a higher-efficacy medication (eg, infliximab, vedolizumab, ozanimod, etrasimod, upadacitinib, risankizumab, and guselkumab) or an intermediate-efficacy medication (golimumab, ustekinumab, tofacitinib, filgotinib, and mirikizumab) rather than a lower-efficacy medication such as adalimumab.
• In patients previously exposed to advanced therapy, particularly tumor necrosis factor (TNF)–alpha antagonists, the panel suggests using a higher-efficacy medication (tofacitinib, upadacitinib, and ustekinumab) or an intermediate-efficacy agent (filgotinib, mirikizumab, risankizumab, and guselkumab) over a lower-efficacy medication (adalimumab, vedolizumab, ozanimod, and etrasimod).
• The panel suggests against the use of thiopurine monotherapy for inducing remission but suggests thiopurine monotherapy over no treatment for maintenance of (typically corticosteroid-induced) remission.
• The panel suggests against the use of methotrexate monotherapy for induction or maintenance of remission.
• Infliximab, adalimumab, and golimumab in combination with an immunomodulator are suggested over monotherapy.
• The panel makes no recommendation for or against non-TNF antagonist biologics in combination with an immunomodulator over non-TNF biologics alone.
• For patients in corticosteroid-free clinical remission for at least 6 months on combination therapy with TNF antagonists and immunomodulators, the panel suggests against withdrawing TNF antagonists but makes no recommendation for or against withdrawing immunomodulators.
• For those who have failed 5-ASAs and have escalated to immunomodulators or advanced therapies, the panel suggests stopping these agents. It suggests the early use of advanced therapies and/or immunomodulator therapy rather than gradual step-up after failure of 5-ASAs.

According to Lewis, the guidance will be useful to both community physicians and highly specialized gastroenterologists. “While few practicing physicians will be able to commit the entirety of the classifications in this guideline to memory, the tool is a quick reference resource to help providers and patients to choose between the many options,” he said.

However, he noted that not all patients and providers may have the same priorities as the guidelines. “There are a few nuances to the methods of the AGA guidelines. For example, the panel prioritized efficacy over safety because the incidence of serious adverse events secondary to medications is relatively rare.”

Lewis also noted that the way the panel classified higher-, intermediate-, and lower-efficacy medications sometimes produced surprising results. “For example, among patients naive to advanced therapies, the IL [interleukin]–23 inhibitors risankizumab and guselkumab were classified as higher efficacy, while the IL-12/23 inhibitor ustekinumab was considered intermediate efficacy,” he said. “These were reversed for patients with prior exposure to advanced therapies, where ustekinumab was considered higher efficacy and all three IL-23 inhibitors were considered intermediate efficacy.”

 

The Future

The panel identified several knowledge gaps that future studies should address. These include a paucity of head-to-head comparison trials, including active comparators to accurately inform positioning of different treatments and therapeutic mechanisms.

The panelists also noted a literature gap on the efficacy of different therapies in the setting of failure or intolerance to non-TNF antagonist advanced therapy, which could be relevant to drugs that may have a greater overlap in their therapeutic mechanisms — for instance, anti-trafficking agents.

They pointed to a paucity of data on how predictive models can inform future treatment selection in the real-world setting. “There is clearly a need for identifying biomarkers predictive of response to individual therapies, to facilitate optimal choice of therapies,” they wrote.

The panel also recognized that novel therapeutic strategies may soon be in use, including combination advanced therapy or episodic use of nonimmunogenic advanced therapies such as small molecules. “Further primary data are required to accurately inform the positioning of such strategies,” they wrote.

These guidelines were fully funded by the AGA Institute. Singh and Agrawal are supported by the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK), and Ananthakrishnan is supported by the NIDDK, as well as by the Leona M. and Harry B. Helmsley Charitable Trust and the Chleck Family Foundation. Singh disclosed Institutional research grants from Pfizer. Agrawal reported consulting for Douglas Pharmaceuticals. Several coauthors disclosed receiving consulting fees and/or research support from various private companies in the healthcare field. One author reported stock ownership stock in Exact Sciences. Lewis reported consulting, advisory board service, or data monitoring for Amgen, Arena Pharmaceuticals, Bristol Myers Squibb, Celgene, Eli Lilly and Company, Galapagos, Gilead, Janssen Pharmaceuticals, Merck, Pfizer, Protagonist Therapeutics, and Sanofi. He received research funding or in-kind support from Nestle Health Science, Takeda, Janssen Pharmaceuticals, AbbVie, and Eli Lilly and has had educational grants from Janssen.

A version of this article appeared on Medscape.com.

In a rapidly expanding therapeutic landscape, the American Gastroenterological Association (AGA) has issued updated practice guidelines for the pharmacological management of moderate to severe ulcerative colitis (UC) in adult outpatients.

“These are the first living guidelines published by a GI society, highlighting the interest and need to provide timely guidance to all stakeholders in a rapidly evolving field,” first author Siddharth Singh, MD, of the Division of Gastroenterology in the Department of Medicine at University of California, San Diego, said in an interview. Living guidance allows for ongoing revision of individual recommendations as new data emerge. Nearly 2 million Americans have UC.

 

Issued in Gastroenterology and updating the last guidance in 2020, the recommendations suggest more efficacious drugs should be used sooner. “Early use of advanced therapies including biologics and small-molecule drugs are more effective than 5-aminosalicylates [5-ASAs] or thiopurines and methotrexate for most patients with moderate to severe UC and those with poor prognostic factors,” coauthor and gastroenterologist Manasi Agrawal, MD, MS, an assistant professor of medicine at Icahn School of Medicine at Mount Sinai in New York City, said in an interview.

“We provide a practical guidance based on best-available evidence to make it easy for the treating clinician to make informed choices from the multiplicity of available treatments for UC,” added guidelines coauthor Ashwin Ananthakrishnan, MBBS, MPH, AGAF, a gastroenterologist at Massachusetts General Hospital in Boston.

 

The comprehensive, patient-centered document comes with this caveat from the AGA panel: “These guidelines are meant to be broad recommendations for management of patients with moderate to severe UC and are not intended to address the intricacies of individual patients,” they wrote. “Provider experience and patient values and preferences can inform treating providers and patients to reasonably choose alternative treatment options.”

One gastroenterologist who has been eagerly awaiting these guidelines but not involved in the panel is James D. Lewis, MD, MSCE, AGAF, a professor of medicine and epidemiology at Perelman School of Medicine at the University of Pennsylvania, Philadelphia. “The choice of medications for moderately to severely active UC has expanded tremendously in the past few years,” he said in an interview. “This resulted in the dismantling of the historical therapeutic pyramid.” And while there are many more treatment options, knowing which medication to use for which patient and in which sequence has become much more complicated. 

“These guidelines will be extremely helpful for clinicians trying to navigate this new era of UC care,” he said.

The guidelines also outline implementation considerations for optimal use in different scenarios. “Key considerations include patient-related factors such as age, frailty, other health conditions, consideration for pregnancy, patient preferences, and access to healthcare,” Agrawal said.

 

Specifics

Overall, the guidance recommends advanced or immunomodulatory therapy after failure of 5-ASAs rather than a step-up approach. Moderate to severe disease is defined as a Mayo endoscopic severity subscore of 2 or 3.

The recommendation may also apply to mild disease in the presence of a high burden of inflammation and a poor prognosis or steroid dependence or resistance.

The AGA guideline panelists took account of differences in treatment efficacy between drugs within the same therapeutic class and made their recommendations by specific drugs rather than therapy class.

Based on varying degrees of evidence certainty, the AGA recommends or suggests the following management specifics in adult outpatients with moderate to severe disease:

• Any of the following is recommended over no treatment: infliximab (Remicade), golimumab (Simponi), vedolizumab (Entyvio), tofacitinib (Xeljanz), upadacitinib (Rinvoq), ustekinumab (Stelara), ozanimod (Zeposia), etrasimod (Velsipity), risankizumab (Skyrizi), and guselkumab (Tremfya).
• Adalimumab (Humira), filgotinib (Jyseleca), and mirikizumab (Omvoh) are suggested over no treatment.
• Biosimilars to infliximab, adalimumab, and ustekinumab can be considered of equivalent efficacy to their originator drugs.
• For patients naive to advanced therapies, the AGA panel proposes using a higher-efficacy medication (eg, infliximab, vedolizumab, ozanimod, etrasimod, upadacitinib, risankizumab, and guselkumab) or an intermediate-efficacy medication (golimumab, ustekinumab, tofacitinib, filgotinib, and mirikizumab) rather than a lower-efficacy medication such as adalimumab.
• In patients previously exposed to advanced therapy, particularly tumor necrosis factor (TNF)–alpha antagonists, the panel suggests using a higher-efficacy medication (tofacitinib, upadacitinib, and ustekinumab) or an intermediate-efficacy agent (filgotinib, mirikizumab, risankizumab, and guselkumab) over a lower-efficacy medication (adalimumab, vedolizumab, ozanimod, and etrasimod).
• The panel suggests against the use of thiopurine monotherapy for inducing remission but suggests thiopurine monotherapy over no treatment for maintenance of (typically corticosteroid-induced) remission.
• The panel suggests against the use of methotrexate monotherapy for induction or maintenance of remission.
• Infliximab, adalimumab, and golimumab in combination with an immunomodulator are suggested over monotherapy.
• The panel makes no recommendation for or against non-TNF antagonist biologics in combination with an immunomodulator over non-TNF biologics alone.
• For patients in corticosteroid-free clinical remission for at least 6 months on combination therapy with TNF antagonists and immunomodulators, the panel suggests against withdrawing TNF antagonists but makes no recommendation for or against withdrawing immunomodulators.
• For those who have failed 5-ASAs and have escalated to immunomodulators or advanced therapies, the panel suggests stopping these agents. It suggests the early use of advanced therapies and/or immunomodulator therapy rather than gradual step-up after failure of 5-ASAs.

According to Lewis, the guidance will be useful to both community physicians and highly specialized gastroenterologists. “While few practicing physicians will be able to commit the entirety of the classifications in this guideline to memory, the tool is a quick reference resource to help providers and patients to choose between the many options,” he said.

However, he noted that not all patients and providers may have the same priorities as the guidelines. “There are a few nuances to the methods of the AGA guidelines. For example, the panel prioritized efficacy over safety because the incidence of serious adverse events secondary to medications is relatively rare.”

Lewis also noted that the way the panel classified higher-, intermediate-, and lower-efficacy medications sometimes produced surprising results. “For example, among patients naive to advanced therapies, the IL [interleukin]–23 inhibitors risankizumab and guselkumab were classified as higher efficacy, while the IL-12/23 inhibitor ustekinumab was considered intermediate efficacy,” he said. “These were reversed for patients with prior exposure to advanced therapies, where ustekinumab was considered higher efficacy and all three IL-23 inhibitors were considered intermediate efficacy.”

 

The Future

The panel identified several knowledge gaps that future studies should address. These include a paucity of head-to-head comparison trials, including active comparators to accurately inform positioning of different treatments and therapeutic mechanisms.

The panelists also noted a literature gap on the efficacy of different therapies in the setting of failure or intolerance to non-TNF antagonist advanced therapy, which could be relevant to drugs that may have a greater overlap in their therapeutic mechanisms — for instance, anti-trafficking agents.

They pointed to a paucity of data on how predictive models can inform future treatment selection in the real-world setting. “There is clearly a need for identifying biomarkers predictive of response to individual therapies, to facilitate optimal choice of therapies,” they wrote.

The panel also recognized that novel therapeutic strategies may soon be in use, including combination advanced therapy or episodic use of nonimmunogenic advanced therapies such as small molecules. “Further primary data are required to accurately inform the positioning of such strategies,” they wrote.

These guidelines were fully funded by the AGA Institute. Singh and Agrawal are supported by the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK), and Ananthakrishnan is supported by the NIDDK, as well as by the Leona M. and Harry B. Helmsley Charitable Trust and the Chleck Family Foundation. Singh disclosed Institutional research grants from Pfizer. Agrawal reported consulting for Douglas Pharmaceuticals. Several coauthors disclosed receiving consulting fees and/or research support from various private companies in the healthcare field. One author reported stock ownership stock in Exact Sciences. Lewis reported consulting, advisory board service, or data monitoring for Amgen, Arena Pharmaceuticals, Bristol Myers Squibb, Celgene, Eli Lilly and Company, Galapagos, Gilead, Janssen Pharmaceuticals, Merck, Pfizer, Protagonist Therapeutics, and Sanofi. He received research funding or in-kind support from Nestle Health Science, Takeda, Janssen Pharmaceuticals, AbbVie, and Eli Lilly and has had educational grants from Janssen.

A version of this article appeared on Medscape.com.

In a rapidly expanding therapeutic landscape, the American Gastroenterological Association (AGA) has issued updated practice guidelines for the pharmacological management of moderate to severe ulcerative colitis (UC) in adult outpatients.

“These are the first living guidelines published by a GI society, highlighting the interest and need to provide timely guidance to all stakeholders in a rapidly evolving field,” first author Siddharth Singh, MD, of the Division of Gastroenterology in the Department of Medicine at University of California, San Diego, said in an interview. Living guidance allows for ongoing revision of individual recommendations as new data emerge. Nearly 2 million Americans have UC.

 

Issued in Gastroenterology and updating the last guidance in 2020, the recommendations suggest more efficacious drugs should be used sooner. “Early use of advanced therapies including biologics and small-molecule drugs are more effective than 5-aminosalicylates [5-ASAs] or thiopurines and methotrexate for most patients with moderate to severe UC and those with poor prognostic factors,” coauthor and gastroenterologist Manasi Agrawal, MD, MS, an assistant professor of medicine at Icahn School of Medicine at Mount Sinai in New York City, said in an interview.

“We provide a practical guidance based on best-available evidence to make it easy for the treating clinician to make informed choices from the multiplicity of available treatments for UC,” added guidelines coauthor Ashwin Ananthakrishnan, MBBS, MPH, AGAF, a gastroenterologist at Massachusetts General Hospital in Boston.

 

The comprehensive, patient-centered document comes with this caveat from the AGA panel: “These guidelines are meant to be broad recommendations for management of patients with moderate to severe UC and are not intended to address the intricacies of individual patients,” they wrote. “Provider experience and patient values and preferences can inform treating providers and patients to reasonably choose alternative treatment options.”

One gastroenterologist who has been eagerly awaiting these guidelines but not involved in the panel is James D. Lewis, MD, MSCE, AGAF, a professor of medicine and epidemiology at Perelman School of Medicine at the University of Pennsylvania, Philadelphia. “The choice of medications for moderately to severely active UC has expanded tremendously in the past few years,” he said in an interview. “This resulted in the dismantling of the historical therapeutic pyramid.” And while there are many more treatment options, knowing which medication to use for which patient and in which sequence has become much more complicated. 

“These guidelines will be extremely helpful for clinicians trying to navigate this new era of UC care,” he said.

The guidelines also outline implementation considerations for optimal use in different scenarios. “Key considerations include patient-related factors such as age, frailty, other health conditions, consideration for pregnancy, patient preferences, and access to healthcare,” Agrawal said.

 

Specifics

Overall, the guidance recommends advanced or immunomodulatory therapy after failure of 5-ASAs rather than a step-up approach. Moderate to severe disease is defined as a Mayo endoscopic severity subscore of 2 or 3.

The recommendation may also apply to mild disease in the presence of a high burden of inflammation and a poor prognosis or steroid dependence or resistance.

The AGA guideline panelists took account of differences in treatment efficacy between drugs within the same therapeutic class and made their recommendations by specific drugs rather than therapy class.

Based on varying degrees of evidence certainty, the AGA recommends or suggests the following management specifics in adult outpatients with moderate to severe disease:

• Any of the following is recommended over no treatment: infliximab (Remicade), golimumab (Simponi), vedolizumab (Entyvio), tofacitinib (Xeljanz), upadacitinib (Rinvoq), ustekinumab (Stelara), ozanimod (Zeposia), etrasimod (Velsipity), risankizumab (Skyrizi), and guselkumab (Tremfya).
• Adalimumab (Humira), filgotinib (Jyseleca), and mirikizumab (Omvoh) are suggested over no treatment.
• Biosimilars to infliximab, adalimumab, and ustekinumab can be considered of equivalent efficacy to their originator drugs.
• For patients naive to advanced therapies, the AGA panel proposes using a higher-efficacy medication (eg, infliximab, vedolizumab, ozanimod, etrasimod, upadacitinib, risankizumab, and guselkumab) or an intermediate-efficacy medication (golimumab, ustekinumab, tofacitinib, filgotinib, and mirikizumab) rather than a lower-efficacy medication such as adalimumab.
• In patients previously exposed to advanced therapy, particularly tumor necrosis factor (TNF)–alpha antagonists, the panel suggests using a higher-efficacy medication (tofacitinib, upadacitinib, and ustekinumab) or an intermediate-efficacy agent (filgotinib, mirikizumab, risankizumab, and guselkumab) over a lower-efficacy medication (adalimumab, vedolizumab, ozanimod, and etrasimod).
• The panel suggests against the use of thiopurine monotherapy for inducing remission but suggests thiopurine monotherapy over no treatment for maintenance of (typically corticosteroid-induced) remission.
• The panel suggests against the use of methotrexate monotherapy for induction or maintenance of remission.
• Infliximab, adalimumab, and golimumab in combination with an immunomodulator are suggested over monotherapy.
• The panel makes no recommendation for or against non-TNF antagonist biologics in combination with an immunomodulator over non-TNF biologics alone.
• For patients in corticosteroid-free clinical remission for at least 6 months on combination therapy with TNF antagonists and immunomodulators, the panel suggests against withdrawing TNF antagonists but makes no recommendation for or against withdrawing immunomodulators.
• For those who have failed 5-ASAs and have escalated to immunomodulators or advanced therapies, the panel suggests stopping these agents. It suggests the early use of advanced therapies and/or immunomodulator therapy rather than gradual step-up after failure of 5-ASAs.

According to Lewis, the guidance will be useful to both community physicians and highly specialized gastroenterologists. “While few practicing physicians will be able to commit the entirety of the classifications in this guideline to memory, the tool is a quick reference resource to help providers and patients to choose between the many options,” he said.

However, he noted that not all patients and providers may have the same priorities as the guidelines. “There are a few nuances to the methods of the AGA guidelines. For example, the panel prioritized efficacy over safety because the incidence of serious adverse events secondary to medications is relatively rare.”

Lewis also noted that the way the panel classified higher-, intermediate-, and lower-efficacy medications sometimes produced surprising results. “For example, among patients naive to advanced therapies, the IL [interleukin]–23 inhibitors risankizumab and guselkumab were classified as higher efficacy, while the IL-12/23 inhibitor ustekinumab was considered intermediate efficacy,” he said. “These were reversed for patients with prior exposure to advanced therapies, where ustekinumab was considered higher efficacy and all three IL-23 inhibitors were considered intermediate efficacy.”

 

The Future

The panel identified several knowledge gaps that future studies should address. These include a paucity of head-to-head comparison trials, including active comparators to accurately inform positioning of different treatments and therapeutic mechanisms.

The panelists also noted a literature gap on the efficacy of different therapies in the setting of failure or intolerance to non-TNF antagonist advanced therapy, which could be relevant to drugs that may have a greater overlap in their therapeutic mechanisms — for instance, anti-trafficking agents.

They pointed to a paucity of data on how predictive models can inform future treatment selection in the real-world setting. “There is clearly a need for identifying biomarkers predictive of response to individual therapies, to facilitate optimal choice of therapies,” they wrote.

The panel also recognized that novel therapeutic strategies may soon be in use, including combination advanced therapy or episodic use of nonimmunogenic advanced therapies such as small molecules. “Further primary data are required to accurately inform the positioning of such strategies,” they wrote.

These guidelines were fully funded by the AGA Institute. Singh and Agrawal are supported by the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK), and Ananthakrishnan is supported by the NIDDK, as well as by the Leona M. and Harry B. Helmsley Charitable Trust and the Chleck Family Foundation. Singh disclosed Institutional research grants from Pfizer. Agrawal reported consulting for Douglas Pharmaceuticals. Several coauthors disclosed receiving consulting fees and/or research support from various private companies in the healthcare field. One author reported stock ownership stock in Exact Sciences. Lewis reported consulting, advisory board service, or data monitoring for Amgen, Arena Pharmaceuticals, Bristol Myers Squibb, Celgene, Eli Lilly and Company, Galapagos, Gilead, Janssen Pharmaceuticals, Merck, Pfizer, Protagonist Therapeutics, and Sanofi. He received research funding or in-kind support from Nestle Health Science, Takeda, Janssen Pharmaceuticals, AbbVie, and Eli Lilly and has had educational grants from Janssen.

A version of this article appeared on Medscape.com.

PHILADELPHIA – The addition of bezlotoxumab to fecal microbiota transplantation (FMT) does not provide any clear added benefit in patients with inflammatory bowel disease (IBD) and recurrent Clostridioides difficile infection (rCDI), according to a randomized controlled trial.

“Given the high efficacy of FMT, the addition of bezlotoxumab may not provide a further reduction in CDI recurrence,” said study author Jessica R. Allegretti, MD, MPH, AGAF, with Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts.

Allegretti presented the findings during a plenary session at the annual meeting of the American College of Gastroenterology (ACG).

Brigham and Women's Hospital

Common and Deadly

CDI is the most common cause of healthcare-associated infection in the United States, leading to roughly 4.8 billion in excess healthcare costs. There are an estimated 500,000 cases each year in the United States, with roughly 30,000 of those cases leading to death.

Patients with IBD have a prevalence of CDI that is 2.5- to 8-fold higher than in peers without IBD, and they also have 4.5-fold higher risk of recurrence. Sequelae of CDI in IBD include exacerbations of IBD, increased hospitalizations, escalation of IBD therapy, and colectomy.

FMT has been shown to be safe and effective in patients with IBD and rCDI.

Bezlotoxumab — a fully human monoclonal antibody that binds to C difficile toxin B — was approved by the US Food and Drug Administration (FDA) in 2016 to reduce the recurrence of CDI in patients aged 18 years and older.

However, there is only limited data on the value of combining these two strategies.

Allegretti and colleagues conducted a multicenter randomized controlled trial to evaluate the impact of FMT in combination with bezlotoxumab in patients with IBD and rCDI.

They enrolled 61 patients (mean age, 38 years, 54% men) with two or more episodes of CDI who received a single colonoscopic FMT. Twenty patients had Crohn’s disease, and 41 had ulcerative colitis.

Thirty patients were randomly allocated to receive a single bezlotoxumab infusion and 31 to receive a placebo infusion prior to FMT.

A total of five participants (8%) experienced a CDI recurrence with confirmed EIA+ stool –4 in the treatment group and 1 in the placebo group (13% vs 3%, P = .15).

Participants in the treatment group had higher odds of CDI recurrence, though this was not statistically significant (odds ratio [OR], 4.6; 95% CI, 0.5-43.9), Allegretti reported.

With regards to C difficile colonization, more patients in the treatment group were decolonized compared with placebo at week 1 (82% vs 68%, P = .22) and at week 12 (83% vs 72%, P = .34). 

Steroid use at the time of FMT was associated with a significant increased risk of ongoing colonization of C difficile at week 12 post-FMT (OR, 4.90; 95% CI, 1.18-20.37; P = .03).

While there were no significant differences in IBD outcomes between groups, there were numerically higher rates of IBD improvement in the treatment group compared to the placebo group 56% vs 46%.

Only one patient had IBD worsen, and this patient was in the placebo group. There were no de novo IBD flares.

FMT alone and with bezlotoxumab were both safe and well tolerated. Two serious adverse events were reported; neither were deemed to be treatment-related.

“This is the first clinical trial to assess the clinical effect of FMT in combination with bezlotoxumab in patients with IBD and rCDI. The data suggest no clear efficacy benefit to this combination compared to FMT alone,” Allegretti told attendees.

“This finding is not surprising given the high rate of efficacy of FMT,” said Ashwin N. Ananthakrishnan, MD, MPH, AGAF, with Massachusetts General Hospital and Harvard Medical School, Boston, who was not involved in the study.

A version of this article first appeared on Medscape.com.

PHILADELPHIA – The addition of bezlotoxumab to fecal microbiota transplantation (FMT) does not provide any clear added benefit in patients with inflammatory bowel disease (IBD) and recurrent Clostridioides difficile infection (rCDI), according to a randomized controlled trial.

“Given the high efficacy of FMT, the addition of bezlotoxumab may not provide a further reduction in CDI recurrence,” said study author Jessica R. Allegretti, MD, MPH, AGAF, with Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts.

Allegretti presented the findings during a plenary session at the annual meeting of the American College of Gastroenterology (ACG).

Brigham and Women's Hospital

Common and Deadly

CDI is the most common cause of healthcare-associated infection in the United States, leading to roughly 4.8 billion in excess healthcare costs. There are an estimated 500,000 cases each year in the United States, with roughly 30,000 of those cases leading to death.

Patients with IBD have a prevalence of CDI that is 2.5- to 8-fold higher than in peers without IBD, and they also have 4.5-fold higher risk of recurrence. Sequelae of CDI in IBD include exacerbations of IBD, increased hospitalizations, escalation of IBD therapy, and colectomy.

FMT has been shown to be safe and effective in patients with IBD and rCDI.

Bezlotoxumab — a fully human monoclonal antibody that binds to C difficile toxin B — was approved by the US Food and Drug Administration (FDA) in 2016 to reduce the recurrence of CDI in patients aged 18 years and older.

However, there is only limited data on the value of combining these two strategies.

Allegretti and colleagues conducted a multicenter randomized controlled trial to evaluate the impact of FMT in combination with bezlotoxumab in patients with IBD and rCDI.

They enrolled 61 patients (mean age, 38 years, 54% men) with two or more episodes of CDI who received a single colonoscopic FMT. Twenty patients had Crohn’s disease, and 41 had ulcerative colitis.

Thirty patients were randomly allocated to receive a single bezlotoxumab infusion and 31 to receive a placebo infusion prior to FMT.

A total of five participants (8%) experienced a CDI recurrence with confirmed EIA+ stool –4 in the treatment group and 1 in the placebo group (13% vs 3%, P = .15).

Participants in the treatment group had higher odds of CDI recurrence, though this was not statistically significant (odds ratio [OR], 4.6; 95% CI, 0.5-43.9), Allegretti reported.

With regards to C difficile colonization, more patients in the treatment group were decolonized compared with placebo at week 1 (82% vs 68%, P = .22) and at week 12 (83% vs 72%, P = .34). 

Steroid use at the time of FMT was associated with a significant increased risk of ongoing colonization of C difficile at week 12 post-FMT (OR, 4.90; 95% CI, 1.18-20.37; P = .03).

While there were no significant differences in IBD outcomes between groups, there were numerically higher rates of IBD improvement in the treatment group compared to the placebo group 56% vs 46%.

Only one patient had IBD worsen, and this patient was in the placebo group. There were no de novo IBD flares.

FMT alone and with bezlotoxumab were both safe and well tolerated. Two serious adverse events were reported; neither were deemed to be treatment-related.

“This is the first clinical trial to assess the clinical effect of FMT in combination with bezlotoxumab in patients with IBD and rCDI. The data suggest no clear efficacy benefit to this combination compared to FMT alone,” Allegretti told attendees.

“This finding is not surprising given the high rate of efficacy of FMT,” said Ashwin N. Ananthakrishnan, MD, MPH, AGAF, with Massachusetts General Hospital and Harvard Medical School, Boston, who was not involved in the study.

A version of this article first appeared on Medscape.com.

PHILADELPHIA – The addition of bezlotoxumab to fecal microbiota transplantation (FMT) does not provide any clear added benefit in patients with inflammatory bowel disease (IBD) and recurrent Clostridioides difficile infection (rCDI), according to a randomized controlled trial.

“Given the high efficacy of FMT, the addition of bezlotoxumab may not provide a further reduction in CDI recurrence,” said study author Jessica R. Allegretti, MD, MPH, AGAF, with Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts.

Allegretti presented the findings during a plenary session at the annual meeting of the American College of Gastroenterology (ACG).

Brigham and Women's Hospital

Common and Deadly

CDI is the most common cause of healthcare-associated infection in the United States, leading to roughly 4.8 billion in excess healthcare costs. There are an estimated 500,000 cases each year in the United States, with roughly 30,000 of those cases leading to death.

Patients with IBD have a prevalence of CDI that is 2.5- to 8-fold higher than in peers without IBD, and they also have 4.5-fold higher risk of recurrence. Sequelae of CDI in IBD include exacerbations of IBD, increased hospitalizations, escalation of IBD therapy, and colectomy.

FMT has been shown to be safe and effective in patients with IBD and rCDI.

Bezlotoxumab — a fully human monoclonal antibody that binds to C difficile toxin B — was approved by the US Food and Drug Administration (FDA) in 2016 to reduce the recurrence of CDI in patients aged 18 years and older.

However, there is only limited data on the value of combining these two strategies.

Allegretti and colleagues conducted a multicenter randomized controlled trial to evaluate the impact of FMT in combination with bezlotoxumab in patients with IBD and rCDI.

They enrolled 61 patients (mean age, 38 years, 54% men) with two or more episodes of CDI who received a single colonoscopic FMT. Twenty patients had Crohn’s disease, and 41 had ulcerative colitis.

Thirty patients were randomly allocated to receive a single bezlotoxumab infusion and 31 to receive a placebo infusion prior to FMT.

A total of five participants (8%) experienced a CDI recurrence with confirmed EIA+ stool –4 in the treatment group and 1 in the placebo group (13% vs 3%, P = .15).

Participants in the treatment group had higher odds of CDI recurrence, though this was not statistically significant (odds ratio [OR], 4.6; 95% CI, 0.5-43.9), Allegretti reported.

With regards to C difficile colonization, more patients in the treatment group were decolonized compared with placebo at week 1 (82% vs 68%, P = .22) and at week 12 (83% vs 72%, P = .34). 

Steroid use at the time of FMT was associated with a significant increased risk of ongoing colonization of C difficile at week 12 post-FMT (OR, 4.90; 95% CI, 1.18-20.37; P = .03).

While there were no significant differences in IBD outcomes between groups, there were numerically higher rates of IBD improvement in the treatment group compared to the placebo group 56% vs 46%.

Only one patient had IBD worsen, and this patient was in the placebo group. There were no de novo IBD flares.

FMT alone and with bezlotoxumab were both safe and well tolerated. Two serious adverse events were reported; neither were deemed to be treatment-related.

“This is the first clinical trial to assess the clinical effect of FMT in combination with bezlotoxumab in patients with IBD and rCDI. The data suggest no clear efficacy benefit to this combination compared to FMT alone,” Allegretti told attendees.

“This finding is not surprising given the high rate of efficacy of FMT,” said Ashwin N. Ananthakrishnan, MD, MPH, AGAF, with Massachusetts General Hospital and Harvard Medical School, Boston, who was not involved in the study.

A version of this article first appeared on Medscape.com.

Many patients with Crohn’s disease (CD) have a heightened immune response to flagellins expressed by commensal gut bacteria Lachnospiraceae, with seroreactivity appearing up to 5 years prior to development of Crohn’s complications, according to investigators.

These findings suggest that the flagellin cytometric bead array used in the present study could serve as a simple diagnostic and prognostic tool for patients with CD, and point to a new therapeutic target, lead author Qing Zhao, MD, PhD, of the University of Alabama at Birmingham, and colleagues reported.

Qing Zhao

Previously, Zhao and colleagues found that about 30% of patients with CD had elevated IgG responses to multiple Lachnospiraceae flagellins, and stronger reactivity was associated with higher flagellin-specific CD4+ T cells in circulation.

“In this study, we aimed to identify immunodominant B cell peptide epitopes shared among Lachnospiraceae bacterial flagellins in patients with CD and to correlate this immune reactivity with the clinical disease course,” the investigators wrote in Gastroenterology.

To this end, the investigators analyzed serum samples from adult CD patients, pediatric CD patients, and healthy infants without inflammatory bowel disease, with data derived from multiple sources. Adult patients with CD were part of a regional cohort recruited at the University of Alabama at Birmingham, while pediatric patients with CD came from the RISK Stratification Study, a multisite cohort study across the United States and Canada. Samples from healthy infants were collected from three diverse geographic locations: Uganda, Sweden, and the United States, providing a broad comparison of immune responses to Lachnospiraceae flagellin across populations.

Samples were analyzed via two main methods: a flagellin peptide microarray and a cytometric bead array. The microarray, comprising sequential Lachnospiraceae-derived peptides, enabled identification of IgG responses specific to individual bacterial peptides. The cytometric bead array allowed for multiplexed detection of IgG, IgA, and IgM antibodies to these peptides, quantifying immune reactivity and enabling correlation with clinical disease data.

This approach revealed that nearly half of patients with CD — both adults and children — had a strong IgG immune response targeting a specific bacterial peptide in the Lachnospiraceae flagellin hinge region. This response was linked to an increased risk of disease complications over time, suggesting the peptide’s potential as a biomarker for CD severity and progression, according to the investigators.

Of note, healthy infants also exhibited an elevated IgG response to the same bacterial peptide at around 1 year of age, but this response declined as they grew older, in contrast to its persistence in CD patients. This difference points to a possible failure in immune tolerance in CD, where the natural immune response to gut bacteria in infancy may become dysregulated, Zhao and colleagues explained.

“The flagellin cytometric bead array used in this study holds potential for a simplified yet robust diagnostic and prognostic assay for Crohn’s disease,” they concluded. “Given that reactivity to the dominant flagellin epitope is strongly associated with the development of disease complications, this technique may also assist in identifying patients with Crohn’s disease who would benefit from early therapy.”

Zhao and colleagues also called for future studies to characterize the role of flagellin hinge peptide–specific IgG antibodies in CD pathogenesis, and to explore the hinge peptide as a potential therapeutic target.The study was supported by a Synergy Award from the Kenneth Rainin Foundation, a Career Development Award from the Crohn’s and Colitis Foundation, and grants from the Department of Veterans Affairs, National Institute of Allergy and Infectious Diseases, National Institutes of Health, and National Institute of Diabetes and Digestive and Kidney Diseases. One coauthor and the University of Alabama at Birmingham hold a patent on Lachnospiraceae A4 Fla2, licensed for clinical application by Prometheus Laboratories. Four study coauthors have filed a patent for the flagellin peptide cytometric bead array. One coauthor serves as the founder and chief scientific officer of ImmPrev Bio, a company developing an antigen-directed immunotherapy for Crohn’s disease.

Many patients with Crohn’s disease (CD) have a heightened immune response to flagellins expressed by commensal gut bacteria Lachnospiraceae, with seroreactivity appearing up to 5 years prior to development of Crohn’s complications, according to investigators.

These findings suggest that the flagellin cytometric bead array used in the present study could serve as a simple diagnostic and prognostic tool for patients with CD, and point to a new therapeutic target, lead author Qing Zhao, MD, PhD, of the University of Alabama at Birmingham, and colleagues reported.

Qing Zhao

Previously, Zhao and colleagues found that about 30% of patients with CD had elevated IgG responses to multiple Lachnospiraceae flagellins, and stronger reactivity was associated with higher flagellin-specific CD4+ T cells in circulation.

“In this study, we aimed to identify immunodominant B cell peptide epitopes shared among Lachnospiraceae bacterial flagellins in patients with CD and to correlate this immune reactivity with the clinical disease course,” the investigators wrote in Gastroenterology.

To this end, the investigators analyzed serum samples from adult CD patients, pediatric CD patients, and healthy infants without inflammatory bowel disease, with data derived from multiple sources. Adult patients with CD were part of a regional cohort recruited at the University of Alabama at Birmingham, while pediatric patients with CD came from the RISK Stratification Study, a multisite cohort study across the United States and Canada. Samples from healthy infants were collected from three diverse geographic locations: Uganda, Sweden, and the United States, providing a broad comparison of immune responses to Lachnospiraceae flagellin across populations.

Samples were analyzed via two main methods: a flagellin peptide microarray and a cytometric bead array. The microarray, comprising sequential Lachnospiraceae-derived peptides, enabled identification of IgG responses specific to individual bacterial peptides. The cytometric bead array allowed for multiplexed detection of IgG, IgA, and IgM antibodies to these peptides, quantifying immune reactivity and enabling correlation with clinical disease data.

This approach revealed that nearly half of patients with CD — both adults and children — had a strong IgG immune response targeting a specific bacterial peptide in the Lachnospiraceae flagellin hinge region. This response was linked to an increased risk of disease complications over time, suggesting the peptide’s potential as a biomarker for CD severity and progression, according to the investigators.

Of note, healthy infants also exhibited an elevated IgG response to the same bacterial peptide at around 1 year of age, but this response declined as they grew older, in contrast to its persistence in CD patients. This difference points to a possible failure in immune tolerance in CD, where the natural immune response to gut bacteria in infancy may become dysregulated, Zhao and colleagues explained.

“The flagellin cytometric bead array used in this study holds potential for a simplified yet robust diagnostic and prognostic assay for Crohn’s disease,” they concluded. “Given that reactivity to the dominant flagellin epitope is strongly associated with the development of disease complications, this technique may also assist in identifying patients with Crohn’s disease who would benefit from early therapy.”

Zhao and colleagues also called for future studies to characterize the role of flagellin hinge peptide–specific IgG antibodies in CD pathogenesis, and to explore the hinge peptide as a potential therapeutic target.The study was supported by a Synergy Award from the Kenneth Rainin Foundation, a Career Development Award from the Crohn’s and Colitis Foundation, and grants from the Department of Veterans Affairs, National Institute of Allergy and Infectious Diseases, National Institutes of Health, and National Institute of Diabetes and Digestive and Kidney Diseases. One coauthor and the University of Alabama at Birmingham hold a patent on Lachnospiraceae A4 Fla2, licensed for clinical application by Prometheus Laboratories. Four study coauthors have filed a patent for the flagellin peptide cytometric bead array. One coauthor serves as the founder and chief scientific officer of ImmPrev Bio, a company developing an antigen-directed immunotherapy for Crohn’s disease.

Many patients with Crohn’s disease (CD) have a heightened immune response to flagellins expressed by commensal gut bacteria Lachnospiraceae, with seroreactivity appearing up to 5 years prior to development of Crohn’s complications, according to investigators.

These findings suggest that the flagellin cytometric bead array used in the present study could serve as a simple diagnostic and prognostic tool for patients with CD, and point to a new therapeutic target, lead author Qing Zhao, MD, PhD, of the University of Alabama at Birmingham, and colleagues reported.

Qing Zhao

Previously, Zhao and colleagues found that about 30% of patients with CD had elevated IgG responses to multiple Lachnospiraceae flagellins, and stronger reactivity was associated with higher flagellin-specific CD4+ T cells in circulation.

“In this study, we aimed to identify immunodominant B cell peptide epitopes shared among Lachnospiraceae bacterial flagellins in patients with CD and to correlate this immune reactivity with the clinical disease course,” the investigators wrote in Gastroenterology.

To this end, the investigators analyzed serum samples from adult CD patients, pediatric CD patients, and healthy infants without inflammatory bowel disease, with data derived from multiple sources. Adult patients with CD were part of a regional cohort recruited at the University of Alabama at Birmingham, while pediatric patients with CD came from the RISK Stratification Study, a multisite cohort study across the United States and Canada. Samples from healthy infants were collected from three diverse geographic locations: Uganda, Sweden, and the United States, providing a broad comparison of immune responses to Lachnospiraceae flagellin across populations.

Samples were analyzed via two main methods: a flagellin peptide microarray and a cytometric bead array. The microarray, comprising sequential Lachnospiraceae-derived peptides, enabled identification of IgG responses specific to individual bacterial peptides. The cytometric bead array allowed for multiplexed detection of IgG, IgA, and IgM antibodies to these peptides, quantifying immune reactivity and enabling correlation with clinical disease data.

This approach revealed that nearly half of patients with CD — both adults and children — had a strong IgG immune response targeting a specific bacterial peptide in the Lachnospiraceae flagellin hinge region. This response was linked to an increased risk of disease complications over time, suggesting the peptide’s potential as a biomarker for CD severity and progression, according to the investigators.

Of note, healthy infants also exhibited an elevated IgG response to the same bacterial peptide at around 1 year of age, but this response declined as they grew older, in contrast to its persistence in CD patients. This difference points to a possible failure in immune tolerance in CD, where the natural immune response to gut bacteria in infancy may become dysregulated, Zhao and colleagues explained.

“The flagellin cytometric bead array used in this study holds potential for a simplified yet robust diagnostic and prognostic assay for Crohn’s disease,” they concluded. “Given that reactivity to the dominant flagellin epitope is strongly associated with the development of disease complications, this technique may also assist in identifying patients with Crohn’s disease who would benefit from early therapy.”

Zhao and colleagues also called for future studies to characterize the role of flagellin hinge peptide–specific IgG antibodies in CD pathogenesis, and to explore the hinge peptide as a potential therapeutic target.The study was supported by a Synergy Award from the Kenneth Rainin Foundation, a Career Development Award from the Crohn’s and Colitis Foundation, and grants from the Department of Veterans Affairs, National Institute of Allergy and Infectious Diseases, National Institutes of Health, and National Institute of Diabetes and Digestive and Kidney Diseases. One coauthor and the University of Alabama at Birmingham hold a patent on Lachnospiraceae A4 Fla2, licensed for clinical application by Prometheus Laboratories. Four study coauthors have filed a patent for the flagellin peptide cytometric bead array. One coauthor serves as the founder and chief scientific officer of ImmPrev Bio, a company developing an antigen-directed immunotherapy for Crohn’s disease.

VIENNA — Guselkumab has been shown to be efficacious vs placebo in patients with moderately to severely active Crohn’s disease (CD), regardless of prior biologic therapy exposure, according to a pooled analysis of the two phase 3 double-blind GALAXI 2 and 3 studies.

“We found that guselkumab was effective in both biologic-naive and biologic-inadequate subpopulations,” said coinvestigator Bruce E. Sands, MD, AGAF, gastroenterologist from Icahn School of Medicine at Mount Sinai, New York City.

These latest results add to the primary results of these studies reported earlier in 2024 that guselkumab was shown to be superior to both placebo and ustekinumab in the same patient population with moderately to severely active CD.

Sands reported the new data in a presentation at the United European Gastroenterology (UEG) Week 2024.

Guselkumab potently blocks interleukin (IL)–23 and binds to CD64, a receptor on cells that produce IL-23. The dual-acting IL-23p19 subunit inhibitor agent is currently under review by the Food and Drug Administration (FDA) for moderately to severely active CD. In September, guselkumab (Tremfya, Johnson & Johnson) was approved for use in moderately to severely active ulcerative colitis.
 

GALAXI 2 and 3 Pooled Dataset

In the two independent, identically designed GALAXI 2 and 3 studies, patients were randomized to guselkumab treatment at either 200 mg intravenous (IV) induction at weeks 0, 4, and 8, followed by 200 mg subcutaneous maintenance every 4 weeks, starting at week 12, or 200 mg IV induction at weeks 0, 4, and 8, followed by 100 mg subcutaneous maintenance every 8 weeks, starting at week 16; or to ustekinumab; or to placebo.

Participants were required to remain on their treatment of initial randomization for a long-term extension study (up to 5 years) looking at clinical, endoscopic, and safety outcomes, except for participants on placebo who were allowed to switch to ustekinumab if clinical response was not met at week 12.

Inclusion criteria for the studies comprised a Crohn’s Disease Activity Index score between 220 and 450, a mean daily stool frequency count > 3 or an abdominal pain score > 1, and a simple endoscopic score for CD score ≥ 6. Participants were also required to have shown an inadequate response or intolerance to oral corticosteroids, 6-mercaptopurine/azathioprine/methotrexate, or biologic therapies.

The pooled dataset included patients on either dose of guselkumab and patients on placebo (total n = 730). Of these, 52% of participants had shown a prior inadequate response to a biologic, 42% were biologic naive, and 6% had prior exposure to biologics but no documented failure. Patients on ustekinumab were not included in this analysis.

Almost all patients (97%) in the biologic-inadequate response group had previously received at least one anti–tumor necrosis factor agent, and around 15% had received vedolizumab. As expected, the biologic-inadequate responders were a lot sicker than the biologic-naive patients, Sands reported.

The composite co–primary endpoints for each guselkumab regimen vs placebo were clinical response at week 12 plus clinical remission at week 48, and clinical response at week 12 plus endoscopic response at week 48.

The major secondary endpoints comprised clinical remission at week 12 and endoscopic response also at week 12.
 

Short- and Long-Term Endpoints in Both Subgroups

In the biologic-naive subgroup, 54.7% of patients receiving the 200-mg dose regimen of guselkumab and 51.7% of those receiving the 100-mg dose regimen showed a clinical response at week 12 plus clinical remission at week 48, compared with 11.5% in the placebo group (P < .001 for both compared with placebo).

In the biologic-inadequate response group, 49.7% of those receiving the 200-mg dose regimen of guselkumab and 45.8% on the 100-mg dose regimen reached the composite endpoint, compared with the placebo response of 12.8% (P < .001 for both compared with placebo).

“You can see a slight decrease in response in the biologic-inadequate responders, but on the whole, the confidence intervals are highly overlapping,” said Sands.

Turning to major secondary endpoints at week 12, clinical remission was reached by 49.6% of the biologic-naive group on the 200-mg guselkumab regimen vs 16.4% on placebo, and by 46.0% of the biologic-inadequate group on the 200-mg regimen vs 19.2% on placebo (P < .001 for both subgroups). Endoscopic response was achieved by 46.3% of patients in the biologic-naive group and 29.0% in the biologic-inadequate group on the 200-mg regimen vs 18.0% and 6.4%, respectively, on placebo (P < .001 for both subgroups).

Sands noted that the drug has an excellent safety profile.

“These data show the drug works for naive patients who have failed conventional therapies, as well as for those who have failed biologic therapies,” so it could be used as a first- or second-line biologic, he added.

Sands reported potential conflicts of interest with AbbVie, Abivax, Adiso Therapeutics, Agomab, Alimentiv, Amgen, AnaptysBio, Arena Pharmaceuticals, Artugen Therapeutics, AstraZeneca, Biora Therapeutics, Boehringer Ingelheim, Boston Pharmaceuticals, Bristol-Myers Squibb, Calibr, Celgene, Celltrion, ClostraBio, Equillium, Enthera, Evommune, Ferring, Fresenius Kabi, Galapagos, Genentech (Roche), Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Index Pharmaceuticals, Innovation Pharmaceuticals, Inotrem, Janssen, Kaleido, Kallyope, Lilly, Merck, Microbiotica, Mobius Care, Morphic Therapeutic, MRM Health, Pfizer, Nexus Therapeutics, Nimbus Discovery, Odyssey Therapeutics, Progenity, Prometheus Biosciences, Prometheus Laboratories, Protagonist Therapeutics, Q32 Bio, Rasayana Therapeutics, Recludix Pharma, Reistone Biopharma, Sun Pharma, Surrozen, Target RWE, Takeda, Teva, Theravance Biopharma, TLL Pharmaceutical, Tr1X, UNION Therapeutics, and Ventyx Biosciences.

A version of this article appeared on Medscape.com.

VIENNA — Guselkumab has been shown to be efficacious vs placebo in patients with moderately to severely active Crohn’s disease (CD), regardless of prior biologic therapy exposure, according to a pooled analysis of the two phase 3 double-blind GALAXI 2 and 3 studies.

“We found that guselkumab was effective in both biologic-naive and biologic-inadequate subpopulations,” said coinvestigator Bruce E. Sands, MD, AGAF, gastroenterologist from Icahn School of Medicine at Mount Sinai, New York City.

These latest results add to the primary results of these studies reported earlier in 2024 that guselkumab was shown to be superior to both placebo and ustekinumab in the same patient population with moderately to severely active CD.

Sands reported the new data in a presentation at the United European Gastroenterology (UEG) Week 2024.

Guselkumab potently blocks interleukin (IL)–23 and binds to CD64, a receptor on cells that produce IL-23. The dual-acting IL-23p19 subunit inhibitor agent is currently under review by the Food and Drug Administration (FDA) for moderately to severely active CD. In September, guselkumab (Tremfya, Johnson & Johnson) was approved for use in moderately to severely active ulcerative colitis.
 

GALAXI 2 and 3 Pooled Dataset

In the two independent, identically designed GALAXI 2 and 3 studies, patients were randomized to guselkumab treatment at either 200 mg intravenous (IV) induction at weeks 0, 4, and 8, followed by 200 mg subcutaneous maintenance every 4 weeks, starting at week 12, or 200 mg IV induction at weeks 0, 4, and 8, followed by 100 mg subcutaneous maintenance every 8 weeks, starting at week 16; or to ustekinumab; or to placebo.

Participants were required to remain on their treatment of initial randomization for a long-term extension study (up to 5 years) looking at clinical, endoscopic, and safety outcomes, except for participants on placebo who were allowed to switch to ustekinumab if clinical response was not met at week 12.

Inclusion criteria for the studies comprised a Crohn’s Disease Activity Index score between 220 and 450, a mean daily stool frequency count > 3 or an abdominal pain score > 1, and a simple endoscopic score for CD score ≥ 6. Participants were also required to have shown an inadequate response or intolerance to oral corticosteroids, 6-mercaptopurine/azathioprine/methotrexate, or biologic therapies.

The pooled dataset included patients on either dose of guselkumab and patients on placebo (total n = 730). Of these, 52% of participants had shown a prior inadequate response to a biologic, 42% were biologic naive, and 6% had prior exposure to biologics but no documented failure. Patients on ustekinumab were not included in this analysis.

Almost all patients (97%) in the biologic-inadequate response group had previously received at least one anti–tumor necrosis factor agent, and around 15% had received vedolizumab. As expected, the biologic-inadequate responders were a lot sicker than the biologic-naive patients, Sands reported.

The composite co–primary endpoints for each guselkumab regimen vs placebo were clinical response at week 12 plus clinical remission at week 48, and clinical response at week 12 plus endoscopic response at week 48.

The major secondary endpoints comprised clinical remission at week 12 and endoscopic response also at week 12.
 

Short- and Long-Term Endpoints in Both Subgroups

In the biologic-naive subgroup, 54.7% of patients receiving the 200-mg dose regimen of guselkumab and 51.7% of those receiving the 100-mg dose regimen showed a clinical response at week 12 plus clinical remission at week 48, compared with 11.5% in the placebo group (P < .001 for both compared with placebo).

In the biologic-inadequate response group, 49.7% of those receiving the 200-mg dose regimen of guselkumab and 45.8% on the 100-mg dose regimen reached the composite endpoint, compared with the placebo response of 12.8% (P < .001 for both compared with placebo).

“You can see a slight decrease in response in the biologic-inadequate responders, but on the whole, the confidence intervals are highly overlapping,” said Sands.

Turning to major secondary endpoints at week 12, clinical remission was reached by 49.6% of the biologic-naive group on the 200-mg guselkumab regimen vs 16.4% on placebo, and by 46.0% of the biologic-inadequate group on the 200-mg regimen vs 19.2% on placebo (P < .001 for both subgroups). Endoscopic response was achieved by 46.3% of patients in the biologic-naive group and 29.0% in the biologic-inadequate group on the 200-mg regimen vs 18.0% and 6.4%, respectively, on placebo (P < .001 for both subgroups).

Sands noted that the drug has an excellent safety profile.

“These data show the drug works for naive patients who have failed conventional therapies, as well as for those who have failed biologic therapies,” so it could be used as a first- or second-line biologic, he added.

Sands reported potential conflicts of interest with AbbVie, Abivax, Adiso Therapeutics, Agomab, Alimentiv, Amgen, AnaptysBio, Arena Pharmaceuticals, Artugen Therapeutics, AstraZeneca, Biora Therapeutics, Boehringer Ingelheim, Boston Pharmaceuticals, Bristol-Myers Squibb, Calibr, Celgene, Celltrion, ClostraBio, Equillium, Enthera, Evommune, Ferring, Fresenius Kabi, Galapagos, Genentech (Roche), Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Index Pharmaceuticals, Innovation Pharmaceuticals, Inotrem, Janssen, Kaleido, Kallyope, Lilly, Merck, Microbiotica, Mobius Care, Morphic Therapeutic, MRM Health, Pfizer, Nexus Therapeutics, Nimbus Discovery, Odyssey Therapeutics, Progenity, Prometheus Biosciences, Prometheus Laboratories, Protagonist Therapeutics, Q32 Bio, Rasayana Therapeutics, Recludix Pharma, Reistone Biopharma, Sun Pharma, Surrozen, Target RWE, Takeda, Teva, Theravance Biopharma, TLL Pharmaceutical, Tr1X, UNION Therapeutics, and Ventyx Biosciences.

A version of this article appeared on Medscape.com.

VIENNA — Guselkumab has been shown to be efficacious vs placebo in patients with moderately to severely active Crohn’s disease (CD), regardless of prior biologic therapy exposure, according to a pooled analysis of the two phase 3 double-blind GALAXI 2 and 3 studies.

“We found that guselkumab was effective in both biologic-naive and biologic-inadequate subpopulations,” said coinvestigator Bruce E. Sands, MD, AGAF, gastroenterologist from Icahn School of Medicine at Mount Sinai, New York City.

These latest results add to the primary results of these studies reported earlier in 2024 that guselkumab was shown to be superior to both placebo and ustekinumab in the same patient population with moderately to severely active CD.

Sands reported the new data in a presentation at the United European Gastroenterology (UEG) Week 2024.

Guselkumab potently blocks interleukin (IL)–23 and binds to CD64, a receptor on cells that produce IL-23. The dual-acting IL-23p19 subunit inhibitor agent is currently under review by the Food and Drug Administration (FDA) for moderately to severely active CD. In September, guselkumab (Tremfya, Johnson & Johnson) was approved for use in moderately to severely active ulcerative colitis.
 

GALAXI 2 and 3 Pooled Dataset

In the two independent, identically designed GALAXI 2 and 3 studies, patients were randomized to guselkumab treatment at either 200 mg intravenous (IV) induction at weeks 0, 4, and 8, followed by 200 mg subcutaneous maintenance every 4 weeks, starting at week 12, or 200 mg IV induction at weeks 0, 4, and 8, followed by 100 mg subcutaneous maintenance every 8 weeks, starting at week 16; or to ustekinumab; or to placebo.

Participants were required to remain on their treatment of initial randomization for a long-term extension study (up to 5 years) looking at clinical, endoscopic, and safety outcomes, except for participants on placebo who were allowed to switch to ustekinumab if clinical response was not met at week 12.

Inclusion criteria for the studies comprised a Crohn’s Disease Activity Index score between 220 and 450, a mean daily stool frequency count > 3 or an abdominal pain score > 1, and a simple endoscopic score for CD score ≥ 6. Participants were also required to have shown an inadequate response or intolerance to oral corticosteroids, 6-mercaptopurine/azathioprine/methotrexate, or biologic therapies.

The pooled dataset included patients on either dose of guselkumab and patients on placebo (total n = 730). Of these, 52% of participants had shown a prior inadequate response to a biologic, 42% were biologic naive, and 6% had prior exposure to biologics but no documented failure. Patients on ustekinumab were not included in this analysis.

Almost all patients (97%) in the biologic-inadequate response group had previously received at least one anti–tumor necrosis factor agent, and around 15% had received vedolizumab. As expected, the biologic-inadequate responders were a lot sicker than the biologic-naive patients, Sands reported.

The composite co–primary endpoints for each guselkumab regimen vs placebo were clinical response at week 12 plus clinical remission at week 48, and clinical response at week 12 plus endoscopic response at week 48.

The major secondary endpoints comprised clinical remission at week 12 and endoscopic response also at week 12.
 

Short- and Long-Term Endpoints in Both Subgroups

In the biologic-naive subgroup, 54.7% of patients receiving the 200-mg dose regimen of guselkumab and 51.7% of those receiving the 100-mg dose regimen showed a clinical response at week 12 plus clinical remission at week 48, compared with 11.5% in the placebo group (P < .001 for both compared with placebo).

In the biologic-inadequate response group, 49.7% of those receiving the 200-mg dose regimen of guselkumab and 45.8% on the 100-mg dose regimen reached the composite endpoint, compared with the placebo response of 12.8% (P < .001 for both compared with placebo).

“You can see a slight decrease in response in the biologic-inadequate responders, but on the whole, the confidence intervals are highly overlapping,” said Sands.

Turning to major secondary endpoints at week 12, clinical remission was reached by 49.6% of the biologic-naive group on the 200-mg guselkumab regimen vs 16.4% on placebo, and by 46.0% of the biologic-inadequate group on the 200-mg regimen vs 19.2% on placebo (P < .001 for both subgroups). Endoscopic response was achieved by 46.3% of patients in the biologic-naive group and 29.0% in the biologic-inadequate group on the 200-mg regimen vs 18.0% and 6.4%, respectively, on placebo (P < .001 for both subgroups).

Sands noted that the drug has an excellent safety profile.

“These data show the drug works for naive patients who have failed conventional therapies, as well as for those who have failed biologic therapies,” so it could be used as a first- or second-line biologic, he added.

Sands reported potential conflicts of interest with AbbVie, Abivax, Adiso Therapeutics, Agomab, Alimentiv, Amgen, AnaptysBio, Arena Pharmaceuticals, Artugen Therapeutics, AstraZeneca, Biora Therapeutics, Boehringer Ingelheim, Boston Pharmaceuticals, Bristol-Myers Squibb, Calibr, Celgene, Celltrion, ClostraBio, Equillium, Enthera, Evommune, Ferring, Fresenius Kabi, Galapagos, Genentech (Roche), Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Index Pharmaceuticals, Innovation Pharmaceuticals, Inotrem, Janssen, Kaleido, Kallyope, Lilly, Merck, Microbiotica, Mobius Care, Morphic Therapeutic, MRM Health, Pfizer, Nexus Therapeutics, Nimbus Discovery, Odyssey Therapeutics, Progenity, Prometheus Biosciences, Prometheus Laboratories, Protagonist Therapeutics, Q32 Bio, Rasayana Therapeutics, Recludix Pharma, Reistone Biopharma, Sun Pharma, Surrozen, Target RWE, Takeda, Teva, Theravance Biopharma, TLL Pharmaceutical, Tr1X, UNION Therapeutics, and Ventyx Biosciences.

A version of this article appeared on Medscape.com.

Irritable bowel syndrome (IBS) is one of the most common conditions encountered by both primary care providers and gastroenterologists, with a pooled global prevalence of 11.2%. This functional bowel disorder is characterized by abdominal pain or discomfort, diarrhea and/or constipation, and bloating.

Unfortunately, IBS is often misunderstood or minimized by some healthcare professionals, according to Alan Desmond, MB, consultant in gastroenterology and general internal medicine, Torbay Hospital, UK National Health Service.

Desmond regularly sees patients who either haven’t been accurately diagnosed or have been told, “Don’t worry, it’s ‘just’ irritable bowel syndrome,” he said at the recent International Conference on Nutrition in Medicine.

A 2017 study involving nearly 2000 patients with a history of gastrointestinal (GI) symptoms found that 43.1% of those who met the criteria for IBS were undiagnosed, and among those who were diagnosed, 26% were not receiving treatment.

“Many clinicians vastly underestimate the impact functional GI symptoms have on our patients in lack of productivity, becoming homebound or losing employment, the inability to enjoy a meal with friends or family, and always needing to know where the nearest bathroom is, for example,” Desmond said in an interview.

IBS can profoundly affect patients’ mental health. One study found that 38% of patients with IBS attending a tertiary care clinic contemplated suicide because they felt hopeless about ever achieving symptom relief.

Today, several dietary, pharmacologic, and psychological/behavioral approaches are available to treat patients with IBS, noted William D. Chey, MD, AGAF, chief of the Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan.

“Each individual patient may need a different combination of these foundational treatments,” he said. “One size doesn’t fit all.”
 

Diagnostic Pathway

One reason IBS is so hard to diagnose is that it’s a “symptom-based disorder, with identification of the condition predicated upon certain key characteristics that are heterogeneous,” Chey said in an interview. “IBS in patient ‘A’ may not present the same way as IBS in patient ‘B,’ although there are certain foundational common characteristics.”

IBS involves “abnormalities in the motility and contractility of the GI tract,” he said. It can present with diarrhea (IBS-D), constipation (IBS-C), or a mixture or alternation of diarrhea and constipation (IBS-M).

Patients with IBS-D often have an exaggerated gastro-colonic response, while those with IBS-C often have a blunted response.

Beyond stool abnormalities and abdominal pain/discomfort, patients often report bloating/distension, low backache, lethargy, nausea, thigh pain, and urinary and gynecologic symptoms.

Historically, IBS has been regarded as a “diagnosis of exclusion” because classic diagnostic tests typically yield no concrete findings. Desmond noted that several blood tests, procedures, imaging studies, and other tests are available to rule out other organic GI conditions, as outlined in the Table.

 

If the patient comes from a geographical region where giardia is endemic, clinicians also should consider testing for the parasite, Chey said.
 

New Understanding of IBS Etiology

Now, advances in the understanding of IBS are changing the approach to the disease.

“The field is moving away from seeing IBS as a ‘wastebasket diagnosis,’ recognizing that there are other causes of a patient’s symptoms,” Mark Pimentel, MD, associate professor of medicine and gastroenterology, Cedars-Sinai, Los Angeles, said in an interview. “What’s made IBS so difficult to diagnose has been the absence of biological markers and hallmark findings on endoscopy.”

Recent research points to novel bacterial causes as culprits in the development of IBS. In particular, altered small bowel microbiota can be triggered by acute gastroenteritis.

Food poisoning can trigger the onset of IBS — a phenomenon called “postinfectious IBS (PI-IBS),” said Pimentel, who is also executive director of the Medically Associated Science and Technology Program at Cedars-Sinai. PI-IBS almost always takes the form of IBS-D, with up to 60% of patients with IBS-D suffering the long-term sequelae of food poisoning.

The types of bacteria most commonly associated with gastroenteritis are Shigella, Campylobacter, Salmonella, and Escherichia coli, Pimentel said. All of them release cytolethal distending toxin B (CdtB), causing the body to produce antibodies to the toxin.

CdtB resembles vinculin, a naturally occurring protein critical for healthy gut function. “Because of this molecular resemblance, the immune system often mistakes one for the other, producing anti-vinculin,” Pimentel explained.

This autoimmune response leads to disruptions in the gut microbiome, ultimately resulting in PI-IBS. The chain of events “doesn’t necessarily happen immediately,” Pimentel said. “You might have developed food poisoning at a party weeks or months ago.”

Acute gastroenteritis is common, affecting as many as 179 million people in the United States annually. A meta-analysis of 47 studies, incorporating 28,270 patients, found that those who had experienced acute gastroenteritis had a fourfold higher risk of developing IBS compared with nonexposed controls.

“The problem isn’t only the IBS itself, but the fact that people with PI-IBS are four times as likely to contract food poisoning again, which can further exacerbate IBS symptoms,” Pimentel said.

Diarrhea-predominant IBS can be detected through the presence of two blood biomarkers — anti-CdtB and anti-vinculin — in a blood test developed by Pimentel and his group.

“Elevation in either of these biomarkers establishes the diagnosis,” Pimentel said. “This is a breakthrough because it represents the first test that can make IBS a ‘diagnosis of inclusion.’”

The blood test also can identify IBS-M but not IBS-C.

Pimentel said that IBS-C is associated with increased levels of methanogenic archaea, which can be diagnosed by a positive methane breath test. “Methane gas slows intestinal contractility, which might result in constipation,” he said.
 

Diet as a Treatment Option

Diet is usually the starting point for IBS treatment, Chey said. “The standard dietary recommendations, as defined by the National Institute for Health and Care Excellence Guidance for managing IBS, are reasonable and common sense — eating three meals a day, avoiding carbonated beverages, excess alcohol, and excess caffeine, and avoiding hard-to-digest foods that can be gas producing.”

A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), which are carbohydrates that aren’t completely absorbed in the intestines, has been shown to be effective in alleviating GI distress in as many as 86% of patients with IBS, leading to improvements in overall GI symptoms as well as individual symptoms (eg, abdominal pain, bloating, constipation, diarrhea, and flatulence).

Desmond recommends the low FODMAP program delineated by Monash University in Australia. The diet should be undertaken only under the supervision of a dietitian, he warned. Moreover, following it on a long-term basis can have an adverse impact on dietary quality and the gut microbiome. Therefore, “it’s important to embark on stepwise reintroduction of FODMAPS under supervision to find acceptable thresholds that don’t cause a return of symptoms.”

A growing body of research suggests that following the Mediterranean diet can be helpful in reducing IBS symptoms. Chey said that some patients who tend to over-restrict their eating might benefit from a less restrictive diet than the typical low FODMAPs diet. For them, the Mediterranean diet may be a good option.
 

Pharmacotherapy for IBS

Nutritional approaches aren’t for everyone, Chey noted. “Some people don’t want to be on a highly restricted diet.” For them, medications addressing symptoms might be a better option.

Antispasmodics — either anticholinergics (hyoscine and dicyclomine) or smooth muscle relaxants (alverine, mebeverine, and peppermint oil) — can be helpful, although they can worsen constipation in a dose-dependent manner. It is advisable to use them on an as-needed rather than long-term basis.

Antidiarrheal agents include loperamide and diphenoxylate.

For constipation, laxatives (eg, senna, bisacodyl, polyethylene glycol, and sodium picosulfate) can be helpful.

Desmond noted that the American Gastroenterological Association does not recommend routine use of probiotics for most GI disorders, including IBS. Exceptions include prevention of Clostridioides difficile, ulcerative colitis, and pouchitis.
 

Targeting the Gut-Brain Relationship

Stress plays a role in exacerbating symptoms in patients with IBS and is an important target for intervention.

“If patients are living with a level of stress that’s impairing, we won’t be able to solve their gut issues until we resolve their stress issues,” Desmond said. “We need to calm the gut-microbiome-brain axis, which is multidimensional and bidirectional.”

Many people — even those without IBS — experience queasiness or diarrhea prior to a major event they’re nervous about, Chey noted. These events activate the brain, which activates the nervous system, which interacts with the GI tract. Indeed, IBS is now recognized as a disorder of gut-brain interaction, he said.

“We now know that the microbiome in the GI tract influences cognition and emotional function, depression, and anxiety. One might say that the gut is the ‘center of the universe’ to human beings,” Chey said.

Evidence-based psychological approaches for stress reduction in patients with IBS include cognitive behavioral therapy, specifically tailored to helping the patient identify associations between IBS symptoms and thoughts, emotions, and actions, as well as learning new behaviors and engaging in stress management. Psychodynamic (interpersonal) therapy enables patients to understand the connection between GI symptoms and interpersonal conflicts, emotional factors, or relationship difficulties.

Gut-directed hypnotherapy (GDH) is a “proven modality for IBS,” Desmond said. Unlike other forms of hypnotherapy, GDH focuses specifically on controlling and normalizing GI function. Studies have shown a reduction of ≥ 30% in abdominal pain in two thirds of participants, with overall response rates up to 85%. It can be delivered in an individual or group setting or via a smartphone.

Desmond recommends mindfulness-based therapy (MBT) for IBS. MBT focuses on the “cultivation of mindfulness, defined as intentional, nonjudgmental, present-focused awareness.” It has been found effective in reducing flares and the markers of gut inflammation in ulcerative colitis, as well as reducing symptoms of IBS.

Chey noted that an emerging body of literature supports the potential role of acupuncture in treating IBS, and his clinic employs it. “I would like to see further research into other areas of CAM [complementary and alternative medicine], including herbal approaches to IBS symptoms as well as stress.”

Finally, all the experts agree that more research is needed.

“The real tragedy is that the NIH invests next to nothing in IBS, in contrast to inflammatory bowel disease and many other conditions,” Pimentel said. “Yet IBS is 45 times more common than inflammatory bowel disease.”

Pimentel hopes that with enough advocacy and recognition that IBS isn’t “just stress-related,” more resources will be devoted to understanding this debilitating condition.

Desmond is the author of a book on the benefits of a plant-based diet. He has also received honoraria, speaking, and consultancy fees from the European Space Agency, Dyson Institute of Engineering and Technology, Riverford Organic Farmers, Ltd., Salesforce Inc., Sentara Healthcare, Saudi Sports for All Federation, the Physicians Committee for Responsible Medicine, The Plantrician Project, Doctors for Nutrition, and The Happy Pear.

Pimentel is a consultant for Bausch Health, Ferring Pharmaceuticals, and Ardelyx. He holds equity in and is also a consultant for Dieta Health, Salvo Health, Cylinder Health, and Gemelli Biotech. Cedars-Sinai has a licensing agreement with Gemelli Biotech and Hobbs Medical.

Chey is a consultant to AbbVie, Ardelyx, Atmo, Biomerica, Gemelli Biotech, Ironwood Pharmaceuticals, Nestlé, QOL Medical, Phathom Pharmaceuticals, Redhill, Salix/Valeant, Takeda, and Vibrant. He receives grant/research funding from Commonwealth Diagnostics International, Inc., US Food and Drug Administration, National Institutes of Health, QOL Medical, and Salix/Valeant. He holds stock options in Coprata, Dieta Health, Evinature, FoodMarble, Kiwi Biosciences, and ModifyHealth. He is a board or advisory panel member of the American College of Gastroenterology, GI Health Foundation, International Foundation for Gastrointestinal Disorders, Rome. He holds patents on My Nutrition Health, Digital Manometry, and Rectal Expulsion Device.

A version of this article appeared on Medscape.com.

Irritable bowel syndrome (IBS) is one of the most common conditions encountered by both primary care providers and gastroenterologists, with a pooled global prevalence of 11.2%. This functional bowel disorder is characterized by abdominal pain or discomfort, diarrhea and/or constipation, and bloating.

Unfortunately, IBS is often misunderstood or minimized by some healthcare professionals, according to Alan Desmond, MB, consultant in gastroenterology and general internal medicine, Torbay Hospital, UK National Health Service.

Desmond regularly sees patients who either haven’t been accurately diagnosed or have been told, “Don’t worry, it’s ‘just’ irritable bowel syndrome,” he said at the recent International Conference on Nutrition in Medicine.

A 2017 study involving nearly 2000 patients with a history of gastrointestinal (GI) symptoms found that 43.1% of those who met the criteria for IBS were undiagnosed, and among those who were diagnosed, 26% were not receiving treatment.

“Many clinicians vastly underestimate the impact functional GI symptoms have on our patients in lack of productivity, becoming homebound or losing employment, the inability to enjoy a meal with friends or family, and always needing to know where the nearest bathroom is, for example,” Desmond said in an interview.

IBS can profoundly affect patients’ mental health. One study found that 38% of patients with IBS attending a tertiary care clinic contemplated suicide because they felt hopeless about ever achieving symptom relief.

Today, several dietary, pharmacologic, and psychological/behavioral approaches are available to treat patients with IBS, noted William D. Chey, MD, AGAF, chief of the Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan.

“Each individual patient may need a different combination of these foundational treatments,” he said. “One size doesn’t fit all.”
 

Diagnostic Pathway

One reason IBS is so hard to diagnose is that it’s a “symptom-based disorder, with identification of the condition predicated upon certain key characteristics that are heterogeneous,” Chey said in an interview. “IBS in patient ‘A’ may not present the same way as IBS in patient ‘B,’ although there are certain foundational common characteristics.”

IBS involves “abnormalities in the motility and contractility of the GI tract,” he said. It can present with diarrhea (IBS-D), constipation (IBS-C), or a mixture or alternation of diarrhea and constipation (IBS-M).

Patients with IBS-D often have an exaggerated gastro-colonic response, while those with IBS-C often have a blunted response.

Beyond stool abnormalities and abdominal pain/discomfort, patients often report bloating/distension, low backache, lethargy, nausea, thigh pain, and urinary and gynecologic symptoms.

Historically, IBS has been regarded as a “diagnosis of exclusion” because classic diagnostic tests typically yield no concrete findings. Desmond noted that several blood tests, procedures, imaging studies, and other tests are available to rule out other organic GI conditions, as outlined in the Table.

 

If the patient comes from a geographical region where giardia is endemic, clinicians also should consider testing for the parasite, Chey said.
 

New Understanding of IBS Etiology

Now, advances in the understanding of IBS are changing the approach to the disease.

“The field is moving away from seeing IBS as a ‘wastebasket diagnosis,’ recognizing that there are other causes of a patient’s symptoms,” Mark Pimentel, MD, associate professor of medicine and gastroenterology, Cedars-Sinai, Los Angeles, said in an interview. “What’s made IBS so difficult to diagnose has been the absence of biological markers and hallmark findings on endoscopy.”

Recent research points to novel bacterial causes as culprits in the development of IBS. In particular, altered small bowel microbiota can be triggered by acute gastroenteritis.

Food poisoning can trigger the onset of IBS — a phenomenon called “postinfectious IBS (PI-IBS),” said Pimentel, who is also executive director of the Medically Associated Science and Technology Program at Cedars-Sinai. PI-IBS almost always takes the form of IBS-D, with up to 60% of patients with IBS-D suffering the long-term sequelae of food poisoning.

The types of bacteria most commonly associated with gastroenteritis are Shigella, Campylobacter, Salmonella, and Escherichia coli, Pimentel said. All of them release cytolethal distending toxin B (CdtB), causing the body to produce antibodies to the toxin.

CdtB resembles vinculin, a naturally occurring protein critical for healthy gut function. “Because of this molecular resemblance, the immune system often mistakes one for the other, producing anti-vinculin,” Pimentel explained.

This autoimmune response leads to disruptions in the gut microbiome, ultimately resulting in PI-IBS. The chain of events “doesn’t necessarily happen immediately,” Pimentel said. “You might have developed food poisoning at a party weeks or months ago.”

Acute gastroenteritis is common, affecting as many as 179 million people in the United States annually. A meta-analysis of 47 studies, incorporating 28,270 patients, found that those who had experienced acute gastroenteritis had a fourfold higher risk of developing IBS compared with nonexposed controls.

“The problem isn’t only the IBS itself, but the fact that people with PI-IBS are four times as likely to contract food poisoning again, which can further exacerbate IBS symptoms,” Pimentel said.

Diarrhea-predominant IBS can be detected through the presence of two blood biomarkers — anti-CdtB and anti-vinculin — in a blood test developed by Pimentel and his group.

“Elevation in either of these biomarkers establishes the diagnosis,” Pimentel said. “This is a breakthrough because it represents the first test that can make IBS a ‘diagnosis of inclusion.’”

The blood test also can identify IBS-M but not IBS-C.

Pimentel said that IBS-C is associated with increased levels of methanogenic archaea, which can be diagnosed by a positive methane breath test. “Methane gas slows intestinal contractility, which might result in constipation,” he said.
 

Diet as a Treatment Option

Diet is usually the starting point for IBS treatment, Chey said. “The standard dietary recommendations, as defined by the National Institute for Health and Care Excellence Guidance for managing IBS, are reasonable and common sense — eating three meals a day, avoiding carbonated beverages, excess alcohol, and excess caffeine, and avoiding hard-to-digest foods that can be gas producing.”

A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), which are carbohydrates that aren’t completely absorbed in the intestines, has been shown to be effective in alleviating GI distress in as many as 86% of patients with IBS, leading to improvements in overall GI symptoms as well as individual symptoms (eg, abdominal pain, bloating, constipation, diarrhea, and flatulence).

Desmond recommends the low FODMAP program delineated by Monash University in Australia. The diet should be undertaken only under the supervision of a dietitian, he warned. Moreover, following it on a long-term basis can have an adverse impact on dietary quality and the gut microbiome. Therefore, “it’s important to embark on stepwise reintroduction of FODMAPS under supervision to find acceptable thresholds that don’t cause a return of symptoms.”

A growing body of research suggests that following the Mediterranean diet can be helpful in reducing IBS symptoms. Chey said that some patients who tend to over-restrict their eating might benefit from a less restrictive diet than the typical low FODMAPs diet. For them, the Mediterranean diet may be a good option.
 

Pharmacotherapy for IBS

Nutritional approaches aren’t for everyone, Chey noted. “Some people don’t want to be on a highly restricted diet.” For them, medications addressing symptoms might be a better option.

Antispasmodics — either anticholinergics (hyoscine and dicyclomine) or smooth muscle relaxants (alverine, mebeverine, and peppermint oil) — can be helpful, although they can worsen constipation in a dose-dependent manner. It is advisable to use them on an as-needed rather than long-term basis.

Antidiarrheal agents include loperamide and diphenoxylate.

For constipation, laxatives (eg, senna, bisacodyl, polyethylene glycol, and sodium picosulfate) can be helpful.

Desmond noted that the American Gastroenterological Association does not recommend routine use of probiotics for most GI disorders, including IBS. Exceptions include prevention of Clostridioides difficile, ulcerative colitis, and pouchitis.
 

Targeting the Gut-Brain Relationship

Stress plays a role in exacerbating symptoms in patients with IBS and is an important target for intervention.

“If patients are living with a level of stress that’s impairing, we won’t be able to solve their gut issues until we resolve their stress issues,” Desmond said. “We need to calm the gut-microbiome-brain axis, which is multidimensional and bidirectional.”

Many people — even those without IBS — experience queasiness or diarrhea prior to a major event they’re nervous about, Chey noted. These events activate the brain, which activates the nervous system, which interacts with the GI tract. Indeed, IBS is now recognized as a disorder of gut-brain interaction, he said.

“We now know that the microbiome in the GI tract influences cognition and emotional function, depression, and anxiety. One might say that the gut is the ‘center of the universe’ to human beings,” Chey said.

Evidence-based psychological approaches for stress reduction in patients with IBS include cognitive behavioral therapy, specifically tailored to helping the patient identify associations between IBS symptoms and thoughts, emotions, and actions, as well as learning new behaviors and engaging in stress management. Psychodynamic (interpersonal) therapy enables patients to understand the connection between GI symptoms and interpersonal conflicts, emotional factors, or relationship difficulties.

Gut-directed hypnotherapy (GDH) is a “proven modality for IBS,” Desmond said. Unlike other forms of hypnotherapy, GDH focuses specifically on controlling and normalizing GI function. Studies have shown a reduction of ≥ 30% in abdominal pain in two thirds of participants, with overall response rates up to 85%. It can be delivered in an individual or group setting or via a smartphone.

Desmond recommends mindfulness-based therapy (MBT) for IBS. MBT focuses on the “cultivation of mindfulness, defined as intentional, nonjudgmental, present-focused awareness.” It has been found effective in reducing flares and the markers of gut inflammation in ulcerative colitis, as well as reducing symptoms of IBS.

Chey noted that an emerging body of literature supports the potential role of acupuncture in treating IBS, and his clinic employs it. “I would like to see further research into other areas of CAM [complementary and alternative medicine], including herbal approaches to IBS symptoms as well as stress.”

Finally, all the experts agree that more research is needed.

“The real tragedy is that the NIH invests next to nothing in IBS, in contrast to inflammatory bowel disease and many other conditions,” Pimentel said. “Yet IBS is 45 times more common than inflammatory bowel disease.”

Pimentel hopes that with enough advocacy and recognition that IBS isn’t “just stress-related,” more resources will be devoted to understanding this debilitating condition.

Desmond is the author of a book on the benefits of a plant-based diet. He has also received honoraria, speaking, and consultancy fees from the European Space Agency, Dyson Institute of Engineering and Technology, Riverford Organic Farmers, Ltd., Salesforce Inc., Sentara Healthcare, Saudi Sports for All Federation, the Physicians Committee for Responsible Medicine, The Plantrician Project, Doctors for Nutrition, and The Happy Pear.

Pimentel is a consultant for Bausch Health, Ferring Pharmaceuticals, and Ardelyx. He holds equity in and is also a consultant for Dieta Health, Salvo Health, Cylinder Health, and Gemelli Biotech. Cedars-Sinai has a licensing agreement with Gemelli Biotech and Hobbs Medical.

Chey is a consultant to AbbVie, Ardelyx, Atmo, Biomerica, Gemelli Biotech, Ironwood Pharmaceuticals, Nestlé, QOL Medical, Phathom Pharmaceuticals, Redhill, Salix/Valeant, Takeda, and Vibrant. He receives grant/research funding from Commonwealth Diagnostics International, Inc., US Food and Drug Administration, National Institutes of Health, QOL Medical, and Salix/Valeant. He holds stock options in Coprata, Dieta Health, Evinature, FoodMarble, Kiwi Biosciences, and ModifyHealth. He is a board or advisory panel member of the American College of Gastroenterology, GI Health Foundation, International Foundation for Gastrointestinal Disorders, Rome. He holds patents on My Nutrition Health, Digital Manometry, and Rectal Expulsion Device.

A version of this article appeared on Medscape.com.

Irritable bowel syndrome (IBS) is one of the most common conditions encountered by both primary care providers and gastroenterologists, with a pooled global prevalence of 11.2%. This functional bowel disorder is characterized by abdominal pain or discomfort, diarrhea and/or constipation, and bloating.

Unfortunately, IBS is often misunderstood or minimized by some healthcare professionals, according to Alan Desmond, MB, consultant in gastroenterology and general internal medicine, Torbay Hospital, UK National Health Service.

Desmond regularly sees patients who either haven’t been accurately diagnosed or have been told, “Don’t worry, it’s ‘just’ irritable bowel syndrome,” he said at the recent International Conference on Nutrition in Medicine.

A 2017 study involving nearly 2000 patients with a history of gastrointestinal (GI) symptoms found that 43.1% of those who met the criteria for IBS were undiagnosed, and among those who were diagnosed, 26% were not receiving treatment.

“Many clinicians vastly underestimate the impact functional GI symptoms have on our patients in lack of productivity, becoming homebound or losing employment, the inability to enjoy a meal with friends or family, and always needing to know where the nearest bathroom is, for example,” Desmond said in an interview.

IBS can profoundly affect patients’ mental health. One study found that 38% of patients with IBS attending a tertiary care clinic contemplated suicide because they felt hopeless about ever achieving symptom relief.

Today, several dietary, pharmacologic, and psychological/behavioral approaches are available to treat patients with IBS, noted William D. Chey, MD, AGAF, chief of the Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan.

“Each individual patient may need a different combination of these foundational treatments,” he said. “One size doesn’t fit all.”
 

Diagnostic Pathway

One reason IBS is so hard to diagnose is that it’s a “symptom-based disorder, with identification of the condition predicated upon certain key characteristics that are heterogeneous,” Chey said in an interview. “IBS in patient ‘A’ may not present the same way as IBS in patient ‘B,’ although there are certain foundational common characteristics.”

IBS involves “abnormalities in the motility and contractility of the GI tract,” he said. It can present with diarrhea (IBS-D), constipation (IBS-C), or a mixture or alternation of diarrhea and constipation (IBS-M).

Patients with IBS-D often have an exaggerated gastro-colonic response, while those with IBS-C often have a blunted response.

Beyond stool abnormalities and abdominal pain/discomfort, patients often report bloating/distension, low backache, lethargy, nausea, thigh pain, and urinary and gynecologic symptoms.

Historically, IBS has been regarded as a “diagnosis of exclusion” because classic diagnostic tests typically yield no concrete findings. Desmond noted that several blood tests, procedures, imaging studies, and other tests are available to rule out other organic GI conditions, as outlined in the Table.

 

If the patient comes from a geographical region where giardia is endemic, clinicians also should consider testing for the parasite, Chey said.
 

New Understanding of IBS Etiology

Now, advances in the understanding of IBS are changing the approach to the disease.

“The field is moving away from seeing IBS as a ‘wastebasket diagnosis,’ recognizing that there are other causes of a patient’s symptoms,” Mark Pimentel, MD, associate professor of medicine and gastroenterology, Cedars-Sinai, Los Angeles, said in an interview. “What’s made IBS so difficult to diagnose has been the absence of biological markers and hallmark findings on endoscopy.”

Recent research points to novel bacterial causes as culprits in the development of IBS. In particular, altered small bowel microbiota can be triggered by acute gastroenteritis.

Food poisoning can trigger the onset of IBS — a phenomenon called “postinfectious IBS (PI-IBS),” said Pimentel, who is also executive director of the Medically Associated Science and Technology Program at Cedars-Sinai. PI-IBS almost always takes the form of IBS-D, with up to 60% of patients with IBS-D suffering the long-term sequelae of food poisoning.

The types of bacteria most commonly associated with gastroenteritis are Shigella, Campylobacter, Salmonella, and Escherichia coli, Pimentel said. All of them release cytolethal distending toxin B (CdtB), causing the body to produce antibodies to the toxin.

CdtB resembles vinculin, a naturally occurring protein critical for healthy gut function. “Because of this molecular resemblance, the immune system often mistakes one for the other, producing anti-vinculin,” Pimentel explained.

This autoimmune response leads to disruptions in the gut microbiome, ultimately resulting in PI-IBS. The chain of events “doesn’t necessarily happen immediately,” Pimentel said. “You might have developed food poisoning at a party weeks or months ago.”

Acute gastroenteritis is common, affecting as many as 179 million people in the United States annually. A meta-analysis of 47 studies, incorporating 28,270 patients, found that those who had experienced acute gastroenteritis had a fourfold higher risk of developing IBS compared with nonexposed controls.

“The problem isn’t only the IBS itself, but the fact that people with PI-IBS are four times as likely to contract food poisoning again, which can further exacerbate IBS symptoms,” Pimentel said.

Diarrhea-predominant IBS can be detected through the presence of two blood biomarkers — anti-CdtB and anti-vinculin — in a blood test developed by Pimentel and his group.

“Elevation in either of these biomarkers establishes the diagnosis,” Pimentel said. “This is a breakthrough because it represents the first test that can make IBS a ‘diagnosis of inclusion.’”

The blood test also can identify IBS-M but not IBS-C.

Pimentel said that IBS-C is associated with increased levels of methanogenic archaea, which can be diagnosed by a positive methane breath test. “Methane gas slows intestinal contractility, which might result in constipation,” he said.
 

Diet as a Treatment Option

Diet is usually the starting point for IBS treatment, Chey said. “The standard dietary recommendations, as defined by the National Institute for Health and Care Excellence Guidance for managing IBS, are reasonable and common sense — eating three meals a day, avoiding carbonated beverages, excess alcohol, and excess caffeine, and avoiding hard-to-digest foods that can be gas producing.”

A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), which are carbohydrates that aren’t completely absorbed in the intestines, has been shown to be effective in alleviating GI distress in as many as 86% of patients with IBS, leading to improvements in overall GI symptoms as well as individual symptoms (eg, abdominal pain, bloating, constipation, diarrhea, and flatulence).

Desmond recommends the low FODMAP program delineated by Monash University in Australia. The diet should be undertaken only under the supervision of a dietitian, he warned. Moreover, following it on a long-term basis can have an adverse impact on dietary quality and the gut microbiome. Therefore, “it’s important to embark on stepwise reintroduction of FODMAPS under supervision to find acceptable thresholds that don’t cause a return of symptoms.”

A growing body of research suggests that following the Mediterranean diet can be helpful in reducing IBS symptoms. Chey said that some patients who tend to over-restrict their eating might benefit from a less restrictive diet than the typical low FODMAPs diet. For them, the Mediterranean diet may be a good option.
 

Pharmacotherapy for IBS

Nutritional approaches aren’t for everyone, Chey noted. “Some people don’t want to be on a highly restricted diet.” For them, medications addressing symptoms might be a better option.

Antispasmodics — either anticholinergics (hyoscine and dicyclomine) or smooth muscle relaxants (alverine, mebeverine, and peppermint oil) — can be helpful, although they can worsen constipation in a dose-dependent manner. It is advisable to use them on an as-needed rather than long-term basis.

Antidiarrheal agents include loperamide and diphenoxylate.

For constipation, laxatives (eg, senna, bisacodyl, polyethylene glycol, and sodium picosulfate) can be helpful.

Desmond noted that the American Gastroenterological Association does not recommend routine use of probiotics for most GI disorders, including IBS. Exceptions include prevention of Clostridioides difficile, ulcerative colitis, and pouchitis.
 

Targeting the Gut-Brain Relationship

Stress plays a role in exacerbating symptoms in patients with IBS and is an important target for intervention.

“If patients are living with a level of stress that’s impairing, we won’t be able to solve their gut issues until we resolve their stress issues,” Desmond said. “We need to calm the gut-microbiome-brain axis, which is multidimensional and bidirectional.”

Many people — even those without IBS — experience queasiness or diarrhea prior to a major event they’re nervous about, Chey noted. These events activate the brain, which activates the nervous system, which interacts with the GI tract. Indeed, IBS is now recognized as a disorder of gut-brain interaction, he said.

“We now know that the microbiome in the GI tract influences cognition and emotional function, depression, and anxiety. One might say that the gut is the ‘center of the universe’ to human beings,” Chey said.

Evidence-based psychological approaches for stress reduction in patients with IBS include cognitive behavioral therapy, specifically tailored to helping the patient identify associations between IBS symptoms and thoughts, emotions, and actions, as well as learning new behaviors and engaging in stress management. Psychodynamic (interpersonal) therapy enables patients to understand the connection between GI symptoms and interpersonal conflicts, emotional factors, or relationship difficulties.

Gut-directed hypnotherapy (GDH) is a “proven modality for IBS,” Desmond said. Unlike other forms of hypnotherapy, GDH focuses specifically on controlling and normalizing GI function. Studies have shown a reduction of ≥ 30% in abdominal pain in two thirds of participants, with overall response rates up to 85%. It can be delivered in an individual or group setting or via a smartphone.

Desmond recommends mindfulness-based therapy (MBT) for IBS. MBT focuses on the “cultivation of mindfulness, defined as intentional, nonjudgmental, present-focused awareness.” It has been found effective in reducing flares and the markers of gut inflammation in ulcerative colitis, as well as reducing symptoms of IBS.

Chey noted that an emerging body of literature supports the potential role of acupuncture in treating IBS, and his clinic employs it. “I would like to see further research into other areas of CAM [complementary and alternative medicine], including herbal approaches to IBS symptoms as well as stress.”

Finally, all the experts agree that more research is needed.

“The real tragedy is that the NIH invests next to nothing in IBS, in contrast to inflammatory bowel disease and many other conditions,” Pimentel said. “Yet IBS is 45 times more common than inflammatory bowel disease.”

Pimentel hopes that with enough advocacy and recognition that IBS isn’t “just stress-related,” more resources will be devoted to understanding this debilitating condition.

Desmond is the author of a book on the benefits of a plant-based diet. He has also received honoraria, speaking, and consultancy fees from the European Space Agency, Dyson Institute of Engineering and Technology, Riverford Organic Farmers, Ltd., Salesforce Inc., Sentara Healthcare, Saudi Sports for All Federation, the Physicians Committee for Responsible Medicine, The Plantrician Project, Doctors for Nutrition, and The Happy Pear.

Pimentel is a consultant for Bausch Health, Ferring Pharmaceuticals, and Ardelyx. He holds equity in and is also a consultant for Dieta Health, Salvo Health, Cylinder Health, and Gemelli Biotech. Cedars-Sinai has a licensing agreement with Gemelli Biotech and Hobbs Medical.

Chey is a consultant to AbbVie, Ardelyx, Atmo, Biomerica, Gemelli Biotech, Ironwood Pharmaceuticals, Nestlé, QOL Medical, Phathom Pharmaceuticals, Redhill, Salix/Valeant, Takeda, and Vibrant. He receives grant/research funding from Commonwealth Diagnostics International, Inc., US Food and Drug Administration, National Institutes of Health, QOL Medical, and Salix/Valeant. He holds stock options in Coprata, Dieta Health, Evinature, FoodMarble, Kiwi Biosciences, and ModifyHealth. He is a board or advisory panel member of the American College of Gastroenterology, GI Health Foundation, International Foundation for Gastrointestinal Disorders, Rome. He holds patents on My Nutrition Health, Digital Manometry, and Rectal Expulsion Device.

A version of this article appeared on Medscape.com.

PHILADELPHIA — Non-fasting breath gas patterns may help identify patients with irritable bowel syndrome (IBS) who are most likely to respond to a low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet, according to a new study.

The low FODMAP diet is the most evidence-based dietary therapy for patients with IBS, but we know that “only about 50% of our patients respond to it,” said principal investigator Prashant Singh, MD, assistant professor at the University of Michigan in Ann Arbor, Michigan. “Exhaled breath gases represent bacterial fermentation of dietary carbohydrates. These measurements could provide a simple biomarker for response to low FODMAP diets.”

Even before starting the low FODMAP diet, “you could see notable differences in breath test patterns between responders and nonresponders,” he said. “We saw that low FODMAP responders had higher hydrogen (H2) and lower methane (CH4) at baseline than nonresponders and had a greater drop in hydrogen following FODMAP restriction vs nonresponders.”

He added that these results imply that responders to this diet may exhibit differences in baseline microbiota composition regarding saccharolytic capacity and/or methanogens. 

Singh presented the findings at the American College of Gastroenterology (ACG) 2024 Annual Scientific Meeting. 
 

Breaths That Can Predict Response

To determine if pre-intervention non-fasting breath patterns are associated with a clinical response to low FODMAP diets, Singh and colleagues enrolled 284 self-selected participants (mean age, 45.2 years) with mild to moderate gastrointestinal (GI) symptoms. Participants used an app-connected breath analyzer to record hourly, non-fasting H2 and CH4 levels during waking hours, in addition to logging meal content and symptom severity (bloating, abdominal pain, and flatulence) on a 0-10 scale. 

Patients were directed to consume their habitual diet for 1 week, before following an app-directed low FODMAP diet for 1 week. Responders were defined as those with a ≥ 30% reduction in at least one mean symptom score. The researchers then compared average hourly H2 and CH4 levels and symptom scores at baseline between low FODMAP diet responders and nonresponders.

Of the participants, 111 were classified as responders and 173 as nonresponders. There were no significant differences between the groups in gender, age, body mass index, or FODMAP per calorie.

Following FODMAP restriction, responders had consistently lower abdominal pain throughout the day and lower bloating and flatulence predominantly in the latter part of the day. Nonresponders experienced no significant changes in key abdominal symptoms after adopting the low FODMAP diet. 

The researchers found that breath tests taken at baseline revealed predictive trends between the groups, even though average FODMAP consumption did not significantly differ between them. Baseline H2 levels were higher among responders than among nonresponders, especially in the morning and evening. However, responders had lower baseline CH4 levels throughout the day. 

Following FODMAP restrictions, responders had a significant drop in non-fasting H2 but not CH4, whereas nonresponders did not have a significant drop in either.

The study was limited by the fact that participants were not clinically diagnosed with IBS, their GI symptoms were mild overall, and no data were available on stool consistency/frequency or fecal microbiome composition for correlation with exhaled breath gas levels.
 

A Potential New Biomarker

Session co-moderator Kyle Staller, MD, MPH, director of the Gastrointestinal Motility Laboratory at Mass General and associate professor of medicine at Harvard Medical School in Boston, Massachusetts, said in an interview that if validated, these findings provide hope for better directing low FODMAP diets to those patients who may benefit. 

Massachusetts General Hospital

There are some patients who may or may not respond to a FODMAP diet, for reasons we don’t yet know, possibly related to fermentation of gas, and it’s helpful to know before starting treatment, he said. It may help us with more of “a precision medicine approach before we really torture people with diets that can be very difficult to adhere to.” 

Staller, who was not involved in the study, added that, “People tend to really focus on small intestinal bacteria overgrowth when it comes to hydrogen and methane production, but in reality, this is really a very agile day-to-day, meal-to-meal responsiveness. 

“It’s a different paradigm,” he continued. “I’d also like to see more data as to why we see the diurnal rhythm” and whether potential factors such as intestinal transit times are playing a role. 

Singh reported receiving royalties from UpToDate. Staller reported receiving research support from Ardelyx and Restasis and serving as a consultant to Anji, Ardelyx, GI Supply, Mahana, Restasis, and Sanofi. Funding associated with the study was not available at the time of publication.

A version of this article appeared on Medscape.com.

PHILADELPHIA — Non-fasting breath gas patterns may help identify patients with irritable bowel syndrome (IBS) who are most likely to respond to a low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet, according to a new study.

The low FODMAP diet is the most evidence-based dietary therapy for patients with IBS, but we know that “only about 50% of our patients respond to it,” said principal investigator Prashant Singh, MD, assistant professor at the University of Michigan in Ann Arbor, Michigan. “Exhaled breath gases represent bacterial fermentation of dietary carbohydrates. These measurements could provide a simple biomarker for response to low FODMAP diets.”

Even before starting the low FODMAP diet, “you could see notable differences in breath test patterns between responders and nonresponders,” he said. “We saw that low FODMAP responders had higher hydrogen (H2) and lower methane (CH4) at baseline than nonresponders and had a greater drop in hydrogen following FODMAP restriction vs nonresponders.”

He added that these results imply that responders to this diet may exhibit differences in baseline microbiota composition regarding saccharolytic capacity and/or methanogens. 

Singh presented the findings at the American College of Gastroenterology (ACG) 2024 Annual Scientific Meeting. 
 

Breaths That Can Predict Response

To determine if pre-intervention non-fasting breath patterns are associated with a clinical response to low FODMAP diets, Singh and colleagues enrolled 284 self-selected participants (mean age, 45.2 years) with mild to moderate gastrointestinal (GI) symptoms. Participants used an app-connected breath analyzer to record hourly, non-fasting H2 and CH4 levels during waking hours, in addition to logging meal content and symptom severity (bloating, abdominal pain, and flatulence) on a 0-10 scale. 

Patients were directed to consume their habitual diet for 1 week, before following an app-directed low FODMAP diet for 1 week. Responders were defined as those with a ≥ 30% reduction in at least one mean symptom score. The researchers then compared average hourly H2 and CH4 levels and symptom scores at baseline between low FODMAP diet responders and nonresponders.

Of the participants, 111 were classified as responders and 173 as nonresponders. There were no significant differences between the groups in gender, age, body mass index, or FODMAP per calorie.

Following FODMAP restriction, responders had consistently lower abdominal pain throughout the day and lower bloating and flatulence predominantly in the latter part of the day. Nonresponders experienced no significant changes in key abdominal symptoms after adopting the low FODMAP diet. 

The researchers found that breath tests taken at baseline revealed predictive trends between the groups, even though average FODMAP consumption did not significantly differ between them. Baseline H2 levels were higher among responders than among nonresponders, especially in the morning and evening. However, responders had lower baseline CH4 levels throughout the day. 

Following FODMAP restrictions, responders had a significant drop in non-fasting H2 but not CH4, whereas nonresponders did not have a significant drop in either.

The study was limited by the fact that participants were not clinically diagnosed with IBS, their GI symptoms were mild overall, and no data were available on stool consistency/frequency or fecal microbiome composition for correlation with exhaled breath gas levels.
 

A Potential New Biomarker

Session co-moderator Kyle Staller, MD, MPH, director of the Gastrointestinal Motility Laboratory at Mass General and associate professor of medicine at Harvard Medical School in Boston, Massachusetts, said in an interview that if validated, these findings provide hope for better directing low FODMAP diets to those patients who may benefit. 

Massachusetts General Hospital

There are some patients who may or may not respond to a FODMAP diet, for reasons we don’t yet know, possibly related to fermentation of gas, and it’s helpful to know before starting treatment, he said. It may help us with more of “a precision medicine approach before we really torture people with diets that can be very difficult to adhere to.” 

Staller, who was not involved in the study, added that, “People tend to really focus on small intestinal bacteria overgrowth when it comes to hydrogen and methane production, but in reality, this is really a very agile day-to-day, meal-to-meal responsiveness. 

“It’s a different paradigm,” he continued. “I’d also like to see more data as to why we see the diurnal rhythm” and whether potential factors such as intestinal transit times are playing a role. 

Singh reported receiving royalties from UpToDate. Staller reported receiving research support from Ardelyx and Restasis and serving as a consultant to Anji, Ardelyx, GI Supply, Mahana, Restasis, and Sanofi. Funding associated with the study was not available at the time of publication.

A version of this article appeared on Medscape.com.

PHILADELPHIA — Non-fasting breath gas patterns may help identify patients with irritable bowel syndrome (IBS) who are most likely to respond to a low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet, according to a new study.

The low FODMAP diet is the most evidence-based dietary therapy for patients with IBS, but we know that “only about 50% of our patients respond to it,” said principal investigator Prashant Singh, MD, assistant professor at the University of Michigan in Ann Arbor, Michigan. “Exhaled breath gases represent bacterial fermentation of dietary carbohydrates. These measurements could provide a simple biomarker for response to low FODMAP diets.”

Even before starting the low FODMAP diet, “you could see notable differences in breath test patterns between responders and nonresponders,” he said. “We saw that low FODMAP responders had higher hydrogen (H2) and lower methane (CH4) at baseline than nonresponders and had a greater drop in hydrogen following FODMAP restriction vs nonresponders.”

He added that these results imply that responders to this diet may exhibit differences in baseline microbiota composition regarding saccharolytic capacity and/or methanogens. 

Singh presented the findings at the American College of Gastroenterology (ACG) 2024 Annual Scientific Meeting. 
 

Breaths That Can Predict Response

To determine if pre-intervention non-fasting breath patterns are associated with a clinical response to low FODMAP diets, Singh and colleagues enrolled 284 self-selected participants (mean age, 45.2 years) with mild to moderate gastrointestinal (GI) symptoms. Participants used an app-connected breath analyzer to record hourly, non-fasting H2 and CH4 levels during waking hours, in addition to logging meal content and symptom severity (bloating, abdominal pain, and flatulence) on a 0-10 scale. 

Patients were directed to consume their habitual diet for 1 week, before following an app-directed low FODMAP diet for 1 week. Responders were defined as those with a ≥ 30% reduction in at least one mean symptom score. The researchers then compared average hourly H2 and CH4 levels and symptom scores at baseline between low FODMAP diet responders and nonresponders.

Of the participants, 111 were classified as responders and 173 as nonresponders. There were no significant differences between the groups in gender, age, body mass index, or FODMAP per calorie.

Following FODMAP restriction, responders had consistently lower abdominal pain throughout the day and lower bloating and flatulence predominantly in the latter part of the day. Nonresponders experienced no significant changes in key abdominal symptoms after adopting the low FODMAP diet. 

The researchers found that breath tests taken at baseline revealed predictive trends between the groups, even though average FODMAP consumption did not significantly differ between them. Baseline H2 levels were higher among responders than among nonresponders, especially in the morning and evening. However, responders had lower baseline CH4 levels throughout the day. 

Following FODMAP restrictions, responders had a significant drop in non-fasting H2 but not CH4, whereas nonresponders did not have a significant drop in either.

The study was limited by the fact that participants were not clinically diagnosed with IBS, their GI symptoms were mild overall, and no data were available on stool consistency/frequency or fecal microbiome composition for correlation with exhaled breath gas levels.
 

A Potential New Biomarker

Session co-moderator Kyle Staller, MD, MPH, director of the Gastrointestinal Motility Laboratory at Mass General and associate professor of medicine at Harvard Medical School in Boston, Massachusetts, said in an interview that if validated, these findings provide hope for better directing low FODMAP diets to those patients who may benefit. 

Massachusetts General Hospital

There are some patients who may or may not respond to a FODMAP diet, for reasons we don’t yet know, possibly related to fermentation of gas, and it’s helpful to know before starting treatment, he said. It may help us with more of “a precision medicine approach before we really torture people with diets that can be very difficult to adhere to.” 

Staller, who was not involved in the study, added that, “People tend to really focus on small intestinal bacteria overgrowth when it comes to hydrogen and methane production, but in reality, this is really a very agile day-to-day, meal-to-meal responsiveness. 

“It’s a different paradigm,” he continued. “I’d also like to see more data as to why we see the diurnal rhythm” and whether potential factors such as intestinal transit times are playing a role. 

Singh reported receiving royalties from UpToDate. Staller reported receiving research support from Ardelyx and Restasis and serving as a consultant to Anji, Ardelyx, GI Supply, Mahana, Restasis, and Sanofi. Funding associated with the study was not available at the time of publication.

A version of this article appeared on Medscape.com.