Harms with placebo in trials of biological therapies and small molecules as maintenance therapy in inflammatory bowel disease: a systematic review and meta-analysis

RCPE in association with the American College of Gastroenterology and the Scottish Society of Gastroenterology - Gastroenterology: A global perspective

On 6 November 2024, the Royal College of Physicians of Edinburgh (RCPE) hosted its annual gastroenterology symposium, marking the first collaboration with the American College of Gastroenterology (ACG) and the Scottish Society of Gastroenterology (SSG). The event addressed key global challenges in gastroenterology, including obesity, liver disease, inflammatory bowel disease (IBD), the gut microbiome, endoscopy quality and artificial intelligence (AI) applications. Discussions emphasised the growing burden of metabolic dysfunction-associated steatotic liver disease (MASLD), with promising pharmacologic and endoscopic interventions emerging. Advances in microbiome-targeted therapies, including faecal microbiota transplantation (FMT), were explored for recurrent Clostridium difficile infection and IBD. Professor David Rubin delivered the esteemed Sir Stanley Davidson lecture, highlighting the era of disease modification in IBD, emphasising early intervention and personalised treatment strategies. The symposium also addressed the role of AI in improving endoscopic detection rates and optimising resource allocation. This international collaboration underscored the importance of a multidisciplinary approach to tackling global digestive diseases, integrating clinical innovation, policy interventions and technological advancements. The event fostered knowledge exchange among global experts, aiming to advance patient care and improve long-term outcomes in gastroenterology.

Prevention and interception trials in inflammatory bowel disease: an international taskforce assessment on clinical trial design

Therapeutic progress in inflammatory bowel disease (IBD) has hitherto focused on reducing inflammation to minimise long-term complications. However, strategies aimed at preventing IBD and attenuating its disease course are particularly appealing. This concept is derived from accumulating evidence for an "at-risk" preclinical state and the associations linking genetic background and numerous environmental exposures to disease pathogenesis. Trials in rheumatoid arthritis and type 1 diabetes have identified interventions to delay disease onset, modify the subsequent disease course (potentially protecting against irreversible tissue and end organ damage), and prolong normal quality of life. Prevention and interception trials have major challenges compared with therapeutic trials across a number of domains, including ethical considerations, eligibility criteria, sample size, and optimal endpoints. This Review investigates important factors in designing high-quality prevention trials and evaluates the feasibility and current progress of such trials in IBD, aiming to identify therapeutic strategies for populations at risk.

Active components unveiling and pharmacodynamic research on Valeriana jatamansi jones for ameliorating ulcerative colitis based on pharmacokinetics and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Valeriana jatamansi Jones (V. jatamansi), a traditional Chinese medicine, is widely used in the treatment of gastrointestinal disorders, such as ulcerative colitis (UC). However, the active components of V. jatamansi with protective effect on the intestinal barrier remains elusive.

AIM OF THE STUDY

This investigation was conducted to confirm the efficacy of V. jatamansi ethanol extract for the treatment of UC and to identify the active compounds in ethanol extract of V. jatamansi that have a protective effect against intestinal barrier damage.

MATERIALS AND METHODS

The role of V. jatamansi extract was assessed on dextrose sodium sulfate (DSS) induced colitis in vivo. The wound healing, apoptosis and epithelial barrier permeability of intestinal epithelial cells (NCM460 cells) were evaluated in vitro. UHPLC-MS method was used to determine the pharmacokinetic characteristics of V. jatamansi extract after oral administration. The effect of absorbed compounds on the intestinal barrier was assessed on NCM460 cells. Fuzzy matter-element analysis was used to explore the main compounds, and the results were verified by FITC-dextran assay. Network pharmacology was used to predict the potential mechanisms and western blotting was used to validate the results.

RESULTS

The ethanol extract ofV. jatamansi relieves symptoms, inflammatory response and intestinal barrier damage in DSS-induced UC. It effectively alleviated DSS-induced epithelial barrier damage in NCM460 cells. Pharmacokinetic analyses indicated that the five components (chlorogenic acid, hesperidin, valerosidate, isochlorogenic acid B and cryptochlorogenic acid) were quickly absorbed into the blood after oral administration of ethanol extract. The fuzzy matter-element analysis and FITC-dextran assay demonstrated that valerosidate and chlorogenic acid played an important role in the protection of the intestinal barrier damage. Network pharmacological analyses and western blotting analyses showed that the ethanol extract of and absorbed components significantly inhibited the Bcl-2/Bax/Caspase-3 signaling pathway, and suppressed DSS-induced apoptosis in NCM460 cells.

CONCLUSION

The ethanol extract of V. jatamansi ameliorates intestinal barrier injury in UC mice through multi-components. Valerosidate and chlorogenic acid were identified as anti-colitis compounds. These provided new insights into finding the active components for the treatment of UC and contribute to the clinical application of V. jatamansi.

Advancing therapeutic frontiers: a pipeline of novel drugs for luminal and perianal Crohn's disease management

Crohn's disease (CD) is a chronic, complex inflammatory disorder of the gastrointestinal tract that presents significant therapeutic challenges. Despite the availability of a wide range of treatments, many patients experience primary non-response, secondary loss of response, or adverse events, limiting the overall effectiveness of current therapies. Clinical trials often report response rates below 60%, partly due to stringent inclusion criteria. Emerging therapies that target novel pathways offer promise in overcoming these limitations. This review explores the latest investigational drugs in phases I, II, and III clinical trials for treating both luminal and perianal CD. We highlight promising therapies that target known mechanisms, including selective Janus kinase inhibitors, anti-adhesion molecules, tumor necrosis factor inhibitors, and IL-23 selective inhibitors. In addition, we delve into novel therapeutic strategies such as sphingosine-1-phosphate receptor modulators, miR-124 upregulators, anti-fractalkine (CX3CL1), anti-TL1A, peroxisome proliferator-activated receptor gamma agonists, TGFBRI/ALK5 inhibitors, anti-CCR9 agents, and other innovative small molecules, as well as combination therapies. These emerging approaches, by addressing new pathways and mechanisms of action, have the potential to surpass the limitations of existing treatments and significantly improve CD management. However, the path to developing new therapies for inflammatory bowel disease (IBD) is fraught with challenges, including complex trial designs, ethical concerns regarding placebo use, recruitment difficulties, and escalating costs. The landscape of IBD clinical trials is shifting toward greater inclusivity, improved patient diversity, and innovative trial designs, such as adaptive and Bayesian approaches, to address these challenges. By overcoming these obstacles, the drug development pipeline can advance more effective, accessible, and timely treatments for CD.

Harms with placebo in trials of biological therapies and small molecules as induction therapy in inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND

Randomised placebo-controlled trials are the gold standard to assess novel drugs in ulcerative colitis and Crohn's disease. However, there might be risks associated with receiving placebo. We aimed to examine the harms associated with receiving placebo in trials of licensed biologics and small molecules for the induction of remission in ulcerative colitis and luminal Crohn's disease in a meta-analysis.

METHODS

We performed a systematic review and meta-analysis. We searched MEDLINE, Embase, Embase Classic, and the Cochrane Central Register of Controlled Trials from database inception to May 30, 2024, for randomised placebo-controlled trials of licensed biologics and small molecules for induction of remission in adults (≥18 years) with moderately to severely active ulcerative colitis or luminal Crohn's disease reporting data on adverse events over a minimum treatment period of 4 weeks. There were no prespecified study exclusion criteria. We extracted summary data and pooled data using a random-effects model for any treatment-emergent adverse event, any drug-related adverse event, infection, worsening of inflammatory bowel disease (IBD) activity, withdrawal due to adverse events, serious adverse events, serious infection, serious worsening of IBD activity, or venous thromboembolic events (VTEs), reporting relative risks (RRs) with 95% CIs. The protocol for this meta-analysis was registered with PROSPERO (CRD42024527341).

FINDINGS

The search identified 10 826 citations, of which 47 trials including 20 987 patients (14 267 [68·0%] receiving active drug and 6720 [32·0%] receiving placebo) were eligible. The risk of any treatment-emergent adverse event was no different with active drug than with placebo (7660/14 267 [53·7%] patients on active drug vs 3758/6720 [55·9%] on placebo; RR 0·97, 95% CI 0·94-1·00; I2 =36%). However, the risks of worsening of IBD activity (563/13 473 [4·2%] vs 530/6252 [8·5%]; 0·48, 0·40-0·59; I2 =54%), withdrawal due to adverse event (401/13 363 [3·0%] vs 299/6267 [4·8%]; 0·62, 0·48-0·79; I2 =46%), serious adverse event (682/14 267 [4·8%] vs 483/6720 [7·2%]; 0·69, 0·59-0·80; I2 =30%), serious infection (140/14 194 [1·0%] vs 91/6647 [1·4%]; 0·67, 0·50-0·89; I2 =0%), serious worsening of IBD activity (187/11 271 [1·7%] vs 189/5056 [3·7%]; 0·45, 0·34-0·60; I2 =27%), or VTEs (13/7542 [0·2%] vs 12/2981 [0·4%]; 0·45, 0·21-0·94; I2 =0%) were all significantly lower with active drug than placebo. Numbers needed to treat with active drug to avoid these potentially serious adverse events ranged from 23 for worsening of IBD activity to 452 for VTEs. 27 randomised controlled trials were judged as low risk of bias across all domains.

INTERPRETATION

Patients with moderately to severely active IBD receiving placebo are more likely to experience significant worsening of IBD activity and some serious adverse events, which might relate to a reduction in risk of these events with active drug. Patients should be counselled about these potential harms, and alternative trial designs to mitigate these harms should be considered.

FUNDING

None.