The anti-TNF monoclonal antibody infliximab offers an effective treatment for patients with Inflammatory Bowel Disease (IBD) refractory to conventional immunomodulator therapies. Successful biologic therapy can lead to clinical and endoscopic remission as well as reduced hospitalisation and requirement for surgery [1].
Unfortunately, as a large protein and chimeric antibody, infliximab is immunogenic and this frequently leads to formation of anti-drug antibodies (ADA), with subsequent secondary loss of response (LOR), drug discontinuation and adverse reactions [2]. Identifying patients at increased risk of developing antibodies prior to treatment may establish which individuals require closer drug level monitoring, concomitant immunomodulator therapy and observation for adverse events.
Previous work by Sazonovs et al. identified the first genetic locus to be robustly associated with immunogenicity to anti-TNF therapies [3]. The HLADQA1*05 allele variant rs2097432, carried by approximately 40% of Europeans, significantly increased the rate of formation of infliximab ADA. In the study reviewed here, Wilson et al. aimed to independently identify whether presence of the variant allele was associated with increased risk of ADA formation, LOR, drug discontinuation and adverse events.
Perianal fistulising Crohn’s Disease is a challenging phenotype affecting more than 20% of patients diagnosed with Crohn’s Disease. It is associated with debilitating symptoms and significant morbidity, with subsequent reduced quality of life and increased disease-related work disability.
Currently treatment remains challenging, incorporating surgical and medical management; the latter is driven largely by biologic agents, specifically anti-tumour necrosis factor (TNF) agents such as adalimumab (ADA) and infliximab (IFX). Whilst ADA and IFX have proven efficacy in inducing and maintaining fistula healing and closure, a significant proportion of patients fail to respond or lose response over time. Increasing evidence suggests that this is in part due to sub-therapeutic drug levels, with or without the presence of antibodies to anti-TNF agents (ATA), with higher target drug levels required for fistula healing compared to mucosal healing in Crohn’s Disease. However, data evaluating the correlation between anti-TNF levels and perianal fistula outcomes, particularly with ADA, remain limited.
The aim of this study was to assess the association between anti-TNF levels and perianal fistula healing and closure with maintenance ADA and IFX therapy.
Pre-treatment frailty is independently associated with increased risk of infections after immunosuppression in patients with Inflammatory Bowel Diseases
Kochar B, Cai W, Cagan A, Ananthakrishnan AN
Gastroenterology 2020 Feb 25;S0016-5085(20)30243-2. doi: 10.1053/j.gastro.2020.02.032. Online ahead of print.
The growing arsenal of therapies available for Inflammatory Bowel Disease (IBD) is improving IBD physicians’ ability to target remission. However, risk of infectious complications associated with immunosuppression is a reality that weighs in the minds of physicians and patients alike, affecting the acceptability of these treatments [1]. Both treatment- and patient-related risk factors for infection have been identified in observational studies. Systemic steroids and combination anti-tumour necrosis factor (anti-TNF) and immunomodulator therapy are particularly associated with increased risk of infection, while non-modifiable patient factors include older age and non-IBD comorbidities [2–4]. Accordingly, this perceived risk results in reduced use of effective therapies in older people, despite risk of disease progression and a need for surgery similar to that in young people [5,6].
As explained by Kochar et al., however, chronological age does not capture the physiological heterogeneity in older populations, possibly leading to treatment being unnecessarily conservative in some. Furthermore, reliance on chronological age may lead to underappreciation of risk in younger people. Accordingly, more accurate tools for risk stratification of patients in the setting of immunosuppressive therapies are required.
How the world has changed during these last couple of months!
I hope you are all doing well despite the circumstances and are coping with the changes in workload, day-to-day activities and research that the pandemic has forced upon us. Also, many Y-ECCOs will have seen their educational programmes and training placed on hold. In Denmark, we have started opening society again since May and the number of infected persons is decreasing. However, there is still a lot of uncertainty about the consequences for society and the health care system. How are things in your country?
Laurent Peyrin-Biroulet is Professor of Gastroenterology and head of the Inflammatory Bowel Disease (IBD) group at the Gastroenterology Department, University Hospital of Nancy, France. He is also the current President of the Groupe d'Etude Thérapeutique des Affections Inflammatoires du Tube Digestif (GETAID). As of February 15, he has been the new President of ECCO and we interviewed him during the ECCO Congress in Vienna.
Addition of azathioprine to the switch of anti-TNF in patients with IBD in clinical relapse with undetectable anti-TNF trough levels and antidrug antibodies: a prospective randomised trial
Roblin X, Williet N, Boschetti G, Phelip JM, Del Tedesco E, Berger AE, Vedrines P, Duru G, Peyrin-Biroulet L, Nancey S, Flourie B, Paul S.
Gut. 2020 Jan 24. doi: 10.1136/gutjnl-2019-319758. [Epub ahead of print]
Anti-tumour necrosis factor-α (anti-TNF) has historically been the mainstay of biologic therapy in Inflammatory Bowel Disease (IBD). However, of those who initially respond to anti-TNF, almost 50% will suffer secondary loss of response (SLR) over subsequent years [1,2]. This SLR is primarily predicated on suboptimal anti-TNF trough levels, with or without detectable anti-drug antibodies (ADAs) [3]. Furthermore the prospective, observational study by Kennedy et al. demonstrated that suboptimal anti-TNF trough levels at week 14 predicted ADAs, low trough levels and worse clinical outcomes [4]. This risk was mitigated for both infliximab and adalimumab by the use of immunomodulators such as azathioprine. This corroborates the retrospective data from other cohorts showing how the addition of an immunomodulator can restore clinical response and favourable pharmacokinetics [5–7]. Remission rates when switching to a second anti-TNF have been shown to be lower when the reason to withdraw the first anti-TNF is SLR as compared to intolerance (45% vs 61%) [8]. In the event that SLR to anti-TNF is due to immunogenicity, a switch to another anti-TNF is associated with a risk of ADA to this new therapy [9,10]. A number of patients will also be on anti-TNF monotherapy at the time of switching having de-escalated from previous combination therapy. We know that open-ended prescription of anti-TNF with azathioprine is not without additional risk, notably infection and lymphoma [11]. Furthermore, de-escalation to anti-TNF monotherapy after a period of combination therapy has been shown in most studies not to impact on relapse rates (49% monotherapy versus 48% combination therapy) [12]. It is in precisely this important group of patients that Roblin et al. sought to compare the use of azathioprine in combination with a second anti-TNF versus this second anti-TNF as monotherapy. Over a follow-up period of 2 years, the rates of clinical and immunogenic failure, and of adverse events, were compared.
Proactive monitoring of adalimumab trough concentration associated with increased clinical remission in children with Crohn's Disease compared with reactive monitoring
Assa A, Matar M, Turner D, Broide E, Weiss B, Ledder O, Guz-Mark A, Rinawi F, Cohen S, Topf-Olivestone C, Shaoul R, Yerushalmi B, Shamir R
Therapeutic drug monitoring (TDM) of the anti-TNF monoclonal antibodies, infliximab and adalimumab, in patients with Inflammatory Bowel Disease is gradually being adopted into routine clinical practice in the United Kingdom [1] and United States [2]. The aim of TDM, measuring an individual’s drug and anti-drug antibody levels, is to assess compliance, drug metabolism and immunogenicity with a view to guiding adjustments or changes in management in order to improve clinical outcomes1. TDM can be proactive, with routine measurement of drug level and anti-drug antibody regardless of clinical outcome, or reactive, with measurement of drug level and anti-drug antibody in the setting of loss of response [3]. Compared to empirical dosing alone, TDM used reactively, at the time of loss of response to an anti-TNF treatment, improves durability of response and safety and leads to significant cost savings [4,5]. The evidence base supporting proactive over reactive TDM is, however, less clear. Two randomised controlled trials done in adults (TAXIT [6] and TAILORIX [7]) did not demonstrate any differences in biological, endoscopic or corticosteroid-free remission between groups, though these trials were limited by methodological limitations and isolating the effect of proactive TDM on defined outcomes was difficult. In contrast, multiple observational studies have concluded that there is less risk of treatment failure and relapse, higher rates of drug persistence and better clinical outcomes in patients who undergo proactive TDM compared to reactive TDM [8–11]. The authors aimed to add to this debate by carrying out a pragmatic, randomised controlled trial assessing whether proactive TDM is superior to reactive testing in children with Crohn’s Disease.
Vedolizumab versus adalimumab for moderate-to-severe Ulcerative Colitis
Sands BE, Peyrin‑Biroulet L, Loftus E, Danese S, Colombel JF, Toruner M, Jonaitis L, Abhyankar B, Chen J, Rogers R, Lirio RA, Bornstein JD, Schreiber S, for the VARSITY Study Group
N Engl J Med 2019;381:1215–26. doi: 10.1056/NEJMoa1905725
The management of Ulcerative Colitis (UC) increasingly involves the use of a biologic agent. Placebo-controlled trials have demonstrated the efficacy of both adalimumab, a tumour necrosis factor (TNF) inhibitor, and vedolizumab, an integrin inhibitor. However, variation in study design makes comparison between such trials difficult. This is particularly evident when comparing rates of clinical remission in the placebo groups of different trials. For example, in the ULTRA 2 trial, which established the superiority of adalimumab over placebo in moderate to severe UC, the 52-week clinical remission rate in the placebo group was just 8.5% compared to 15.9% in GEMINI 1, the placebo-controlled trial of vedolizumab [1,2]. In the absence of head-to-head trials between biologics there is a lack of data to inform clinicians of the best choice of agent. VARSITY is the first head-to-head trial to compare the efficacy and safety of vedolizumab and adalimumab in moderate to severely active UC.
Bringing basic science from the bench to the bed, and back, can be challenging for both scientists and clinicians. In order to encourage young scientists and clinicians to collaborate and to approach similar scientific questions from a different – but joint – perspective, the Y-ECCO Basic Science Workshop was founded years ago. Every year, the Y-ECCO Committee invites outstanding senior experts to give a state of the art overview on hot topics in the field. Furthermore, these top-notch speakers not only moderate the discussions following abstract presentations but also inspire and stimulate full-time researchers and young clinicians to do basic science at the start of their careers.
Efficacy and safety of mirikizumab in a randomized phase 2 study of patients with Ulcerative Colitis
Sandborn WJ, Ferrante M, Bhandari BR, Berliba E, Feagan BG, Hibi T, Tuttle JL, Klekotka P, Friedrich S, Durante M, Morgan-Cox M, Laskowski J, Schmitz J, D'Haens GR
Gastroenterology. 2019;doi: https://doi.org/10.1053/j.gastro.2019.08.043. [Epub ahead of print]
Interleukin-23 (IL23) contributes to the pathogenesis of chronic inflammatory diseases, including Ulcerative Colitis (UC), by maintaining and amplifying T helper 17 cells and stimulating many innate immune cells. IL-23 is a heterodimeric cytokine composed of a p40 subunit (shared by IL12) and a p19 subunit (IL-23p19). Ustekinumab, a monoclonal antibody targeting the shared p40 subunit, is effective for treatment of Crohn’s Disease (CD) and psoriasis [1–3]. However, studies in patients with psoriasis have suggested that selective targeting of the IL23 pathway by blocking IL-23p19 is more effective than ustekinumab [4, 5]. Whilst promising phase 2 results have been observed in CD patients following treatment targeting IL-23p19 [6, 7], the role of this therapeutic strategy in UC is unknown. Mirikizumab (LY3074828) is a humanised immunoglobulin G4 (IgG4)-variant monoclonal antibody that binds to the IL-23p19 subunit. The current study evaluated the efficacy and safety of mirikizumab for the treatment of patients with moderate-to-severely active UC.
Johan Burisch
Charlotte Hedin 
Bram Verstockt