Interpreting Registrational Clinical Trials of Biological Therapies in Adults with Inflammatory Bowel Diseases

Representation and reporting of diverse groups in randomised controlled trials of pharmacological agents in inflammatory bowel disease: a systematic review

Inflammatory bowel disease (IBD) is now recognised as a global disease, with incidence rapidly increasing in newly industrialised countries in South America, Asia, and Africa. Trials in IBD, therefore, should adequately represent diverse groups with respect to gender, age, place of residence, race, and ethnicity to ensure the global applicability and generalisability of their findings. In this systematic review, we searched PubMed and Embase for randomised controlled trials (RCTs) published in English from Jan 1, 1995, to Jan 13, 2023, evaluating the efficacy of any pharmacological intervention in patients with IBD. Of 7543 records yielded in the search, we included 617 records reporting data from 627 RCTs and 108 986 participants. The results show a paucity of adequate representation of diverse groups in these RCTs. This finding was true for various groups, including racially and ethnically diverse populations, older (aged >65 years) and younger (aged <18 years) populations, those who identify outside of the gender binary, and people from South America and Africa. Also, some regions had an apparent scarcity of funding sources for trials. Pharmaceutical companies and clinical trial organisations should aim to ensure adequate representation of such under-represented groups in future IBD trials.

Comparative Effectiveness Research: A Roadmap to Sail the Seas of IBD Therapies

The drug pipeline for the treatment of inflammatory bowel disease (IBD) has dramatically expanded over the last two decades, and it is expected to further grow in the upcoming years with the introduction of new agents with different mechanisms of action. However, such an increase of therapeutic options needs to be paralleled with an appropriate development of research to help physicians in the decision-making process when choosing which drug to prescribe. On the population level, comparative effectiveness research (CER) is intended to explore and identify relevant differences-in terms of both efficacy and safety outcomes-amongst different therapeutic regimens and/or strategies, in order to find the correct placement for each treatment in the therapeutic algorithm. CER revolves around three cornerstones: network meta-analyses, head-to-head trials and real-world studies, each of which has specific pros and cons, and can therefore offer answers to different questions. In this review, we aim to provide an overview on the methodological features specific to each of these research approaches, as well as to illustrate the main findings coming from CER on IBD target therapies (i.e., biologics and small molecules) and to discuss their appropriate interpretation.

A propensity score weighted comparison of vedolizumab and adalimumab in Crohn's disease

BACKGROUND AND AIM

There are no head-to-head randomized controlled trials between biologics in Crohn's disease (CD). We aimed to perform a multicenter, real-life comparison of the effectiveness of vedolizumab (VDZ) and adalimumab (ADA) in CD.

METHODS

Data of consecutive patients with CD treated with VDZ and ADA from January 2016 to April 2019 were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Disease. The effectiveness was evaluated at 12, 52 weeks, and as failure-free survival at the end of follow up. Propensity score analysis was performed using the inverse probability of treatment weighting method.

RESULTS

Five hundred eighty-five treatments (VDZ: n = 277; ADA: n = 308) were included (median follow-up: 56.0 weeks). After 12 weeks, a clinical response was achieved in 64.3% patients treated with VDZ and in 83.1% patients treated with ADA (odds ratio [OR] 0.65, 95% confidence interval [CI] 0.38-1.10, P = 0.107), while at 52 weeks, a clinical response was observed in 54.0% patients treated with VDZ and in 69.1% patients treated with ADA (OR 0.77, 95% CI 0.45-1.31, P = 0.336). Cox survival analysis weighted for propensity score showed no significant difference in the probability of failure-free survival between the two drugs (hazard ratio = 1.20, 95% CI 0.83-1.74, P = 0.340). Post-treatment endoscopic response and mucosal healing rates were similar between the two groups (endoscopic response: 35.3% for VDZ and 25.5% for ADA, P = 0.15; mucosal healing: 31.8% for VDZ and 33.8% for ADA, P = 0.85).

CONCLUSIONS

In the first study comparing VDZ and ADA in CD via propensity score analysis, the drugs showed comparable effectiveness and a similar safety profile.

A propensity score weighted comparison of Vedolizumab, Adalimumab, and Golimumab in patients with ulcerative colitis

BACKGROUND

No real-life study on the comparative effectiveness of Vedolizumab (VDZ), Adalimumab (ADA), and Golimumab (GOL) in ulcerative colitis (UC) is currently available.

AIMS

To compare the effectiveness of the three biologics in consecutive patients with UC.

METHODS

A three-arms propensity score-adjusted analysis was performed using the Inverse Probability of Treatment Weighting method.

RESULTS

463 treatments (VDZ: n = 187; ADA: n = 168; GOL: n = 108) were included (median follow-up: 47.6 weeks). At 12 weeks (n = 463), a steroid-free remission was reported in 24.1% patients in the VDZ group, in 33.3% patients in the ADA group, and in 30.6% patients in the GOL group (p = n.s. for all comparisons). At 52 weeks (n = 377), a steroid-free remission was reported in 51.5% patients in the VDZ group, in 31.2% patients in the ADA group, and in 29.4% patients in the GOL group (p = 0.002 for VDZ vs. ADA, p = 0.001 for VDZ vs. GOL, p = n.s. for ADA vs. GOL). Cox survival analysis demonstrated that patients treated with VDZ had reduced probability of treatment discontinuation compared to those treated with ADA (HR: 0.42, 95% CI 0.28-0.64, p < 0.001) and GOL (HR: 0.30, 95% CI 0.19-0.46, p < 0.001), while patients treated with ADA had reduced risk of treatment discontinuation compared to those treated with GOL (HR: 0.71, 95% CI 0.50-1.00, p = 0.048).

CONCLUSIONS

VDZ was superior to ADA and GOL at 52 weeks and as treatment persistence, while ADA showed a superior treatment persistence compared to GOL.

Head-to-head trials in inflammatory bowel disease: past, present and future

With the increase in the number of novel drugs for inflammatory bowel disease (IBD), comparing therapeutic options or strategies has become a key challenge in IBD trials. Head-to-head trials designed and powered to enable formal comparisons are the gold standard in comparative research. Indeed, these trials are requested by some health authorities for evaluating the positioning of new treatments in IBD, as well as helping prescribing physicians to select the most appropriate treatment options for their patients. Despite head-to-head trials including aminosalicylate therapy in IBD having been performed decades ago, the first results of a randomized controlled trial directly comparing biologic agents with different modes of action have only now been published, mainly owing to important methodological issues. This Perspective provides an overview of the past, current and future concepts in IBD trial design, with a detailed focus on the role of comparative research and the challenges and pitfalls in undertaking and interpreting the results from such studies.

Changes in the Management of Patients with Crohn's Disease Based on Magnetic Resonance Enterography Patterns

Background and Aims

Magnetic resonance enterography (MRE) has become an important modality of radiological imaging in the evaluation of Crohn's disease (CD). The aim of this study was to investigate the impact of MRE in the assessment of disease activity and abdominal complications and in the making of therapeutic decisions for patients with CD.

Methods

In a cross-sectional retrospective study, we selected 74 patients with CD who underwent MRE and ileocolonoscopy with an interval between the two exams of up to 30 days between January 2011 and December 2017. We assessed the parameters of the images obtained by MRE and investigated the agreement with the level of disease activity and complications determined by a clinical evaluation, inflammatory biomarkers, and endoscopy, as well as the resulting changes in medical and surgical management.

Results

Changes in medical management were detected in 41.9% of patients. Significant changes in medical decisions were observed in individuals with a purely penetrating (P = .012) or a mixed (P = .024) MRE pattern. Patients with normal MRE patterns had a correlation with unchanged medical decisions (P = .001). There were statistically significant agreements between the absence of inflammatory criteria on MRE and remission according to the Harvey and Bradshaw index (HBI) (P = .037), the presence of inflammatory criteria on MRE and positive results for calprotectin (P = .005), and penetrating criteria on MRE and the scoring endoscopic system for Crohn's disease (SES-CD), indicating active disease (P = .048). Finally, there was significant agreement between the presence of fibrostenotic criteria and a long disease duration (P = .027).

Conclusion

MRE discloses disease activity and complications not apparent with other modalities and results in changes in therapeutic decisions. In addition to being used for diagnosis, MRE should be routinely used in the follow-up of CD patients.

Efficacy and safety of biosimilar CT-P13 compared with originator infliximab in patients with active Crohn's disease: an international, randomised, double-blind, phase 3 non-inferiority study

BACKGROUND

The infliximab biosimilar CT-P13 was approved for use in Crohn's disease after clinical comparison with originator infliximab in ankylosing spondylitis and rheumatoid arthritis; however, concerns about such indication extrapolation have been expressed. This study investigated whether CT-P13 is non-inferior to infliximab in patients with Crohn's disease who were naive to biological therapy.

METHODS

In this randomised, multicentre, double-blind, phase 3 non-inferiority study, we enrolled patients with active Crohn's disease who had not responded to, or were intolerant to, non-biological treatments. Patients were randomly assigned (1:1:1:1) to receive CT-P13 then CT-P13, CT-P13 then infliximab, infliximab then infliximab, or infliximab then CT-P13, with switching occurring at week 30. Patients received 5 mg/kg CT-P13 or infliximab at weeks 0, 2, 6, and then every 8 weeks up to week 54. The primary endpoint was the proportion of patients with a decrease of 70 points or more in Crohn's Disease Activity Index (CDAI) from baseline to week 6. A non-inferiority margin of -20% was set (CT-P13 was non-inferior to infliximab if the lower limit of the two-sided 95% CI for the treatment difference was greater than -20). This trial is registered with ClinicalTrials.gov, number NCT02096861, and is completed.

FINDINGS

Between Aug 20, 2014, and Feb 15, 2017, 308 patients were assessed for eligibility, and 220 patients were enrolled: 111 were randomly assigned to initiate CT-P13 (56 to the CT-P13-CT-P13 group and 55 to the CT-P13-infliximab group) and 109 to initiate infliximab (54 to the infliximab-infliximab group and 55 to the infliximab-CT-P13 group). CDAI-70 response rates at week 6 were similar for CT-P13 (77 [69·4%, 95% CI 59·9 to 77·8] of 111) and infliximab (81 [74·3%, 95% CI 65·1 to 82·2] of 109; difference -4·9% [95% CI -16·9 to 7·3]), thereby establishing non-inferiority. Over the total study period, 147 (67%) patients experienced at least one treatment-emergent adverse event (36 [64%] in the CT-P13-CT-P13 group, 34 [62%] in the CT-P13-infliximab group, 37 [69%] in the infliximab-infliximab group, and 40 [73%] in the infliximab-CT-P13 group).

INTERPRETATION

This study showed non-inferiority of CT-P13 to infliximab in patients with active Crohn's disease. Biosimilar CT-P13 could be a new option for the treatment of active Crohn's disease.

FUNDING

Celltrion, Pfizer.

Loss of Response to Vedolizumab and Ability of Dose Intensification to Restore Response in Patients With Crohn's Disease or Ulcerative Colitis: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Vedolizumab is effective and safe for the treatment of Crohn's disease (CD) and ulcerative colitis (UC). Little is known about the incidence rate of loss of response to vedolizumab maintenance therapy or whether dose intensification restores response to this drug.

METHODS

We searched PubMed, Scopus and conference abstracts (Digestive Disease Week, European Crohn's and Colitis Organization, and United European Gastroenterology Week), through December 2017, for experimental or observational cohort studies of vedolizumab use in adult patients with CD or UC; we identified studies that provided sufficient data to determine the incidence rate of loss of response among initial responders and the ability of dose intensification to restore response. Two reviewers independently abstracted study data and outcomes and rated each study's risk of bias. The studies were evaluated for heterogeneity and publication bias. Summary estimates were calculated using random effects models.

RESULTS

We analyzed data from 10 eligible cohorts; most patients had received prior treatment with a tumor necrosis factor antagonist. The pooled incidence rates of loss of response were 47.9 per 100 person-years of follow up (95% CI, 26.3‒87.0; I² = 74%) among patients with CD and 39.8 per 100 person-years of follow up (95% CI, 35.0‒45.3; I² = 0%) among patients with UC. Dose intensification restored response to the drug in 53.8% of secondary non-responders (95% CI, 21.8%‒82.9%; I² = 77%).

CONCLUSIONS

In a systematic review and meta-analysis, we found high proportions of patients with CD or UC to lose responsiveness to vedolizumab maintenance therapy. Dose intensification restores responsiveness to more than half of these patients. Additional studies are warranted to inform clinical decision making.

Retention Rate, Persistence and Safety of Adalimumab in Inflammatory Bowel Disease: A Real-Life, 9-Year, Single-Center Experience in Italy

BACKGROUND

"Real-life" data of retention rate and persistence of adalimumab in inflammatory bowel disease are still limited.

AIMS

To analyze retention rate, persistence, and safety of adalimumab in a 9-year real-life cohort of inflammatory bowel disease patients.

METHODS

In this observational, retrospective single-center study, all adult patients treated with adalimumab as the first- and second-line biological treatment for steroid-dependent or refractory inflammatory bowel disease between March 2008 and March 2017 were included. Primary outcomes were persistence, retention rate, and adverse events; the secondary outcome was the identification of predictors of withdrawal.

RESULTS

Ninety-six out of 181 patients (53%) withdrew their first course of adalimumab. The retention rate was 47% and 46.9% in Crohn's disease and ulcerative colitis patients, respectively; median persistence was 26 and 24 months in CD and UC patients, respectively. The cumulative probability of treatment persistence was 80.2%, 54.5%, and 29.6% and 69.6%, 40.4%, and 21.5% in CD and UC patients, respectively. The incidence rate of any adverse event was 12.5/100 patients-year; severe adverse events were 1.7/100 patients-year. The Cox regression revealed that CD patients with baseline disease duration > 72 months have a higher likelihood for withdrawal due to failure and/or adverse events (HR 1.62, 95% CI 1-2.62, p = 0.04); no predictors of discontinuation were found in UC.

CONCLUSIONS

Adalimumab showed a great persistence in the first 12 months of therapy and excellent safety profile. Early treatment of CD patients could increase efficacy and reduce the adverse event rate.

Recent advances and emerging therapies in the non-surgical management of ulcerative colitis

The so-called “biologicals” (monoclonal antibodies to various inflammatory targets like tumor necrosis factor or integrins) have revolutionized the treatment of inflammatory bowel diseases. In ulcerative colitis, they have an established role in inducing remission in steroid-refractory disease and, thereafter, maintaining remission with or without azathioprine. Nevertheless, their limitations are also obvious: lack of primary response or loss of response during maintenance as well as various, in part severe, side effects. The latter are less frequent in anti-integrin treatment, but efficacy, especially during induction, is delayed. New antibodies as well as small molecules have also demonstrated clinical efficacy and are soon to be licensed for ulcerative colitis. None of these novel drugs seems to be much more effective overall than the competition, but they provide new options in otherwise refractory patients. This increasing complexity requires new algorithms, but it is still premature to outline each drug’s role in future treatment paradigms.

Should we use anti-tumor necrosis factor agents or vedolizumab as first-line biological therapy in ulcerative colitis?

Randomized controlled trials with direct comparisons between the different available biological agents in ulcerative colitis are lacking. The comparative efficacy, safety and tolerability, patient profile, patient preference and costs should be taken into account when choosing an appropriate first-line biological. Tumor necrosis factor antagonists have a systemic mode of action, while vedolizumab is mainly gut-selective, and this influences the clinical profile of both treatment options. Tofacitinib will further expand the therapeutic armamentarium in ulcerative colitis. Results of ongoing head-to-head trials between biological agents are likely to change clinical practice in the near future. Biomarkers that predict response to different treatment options in an individual patient are warranted.