Dr Paolo Biancheri (Inflammatory Bowel Disease)

Institution: University of East Anglia

Title: Proteolytic degradation of anti-tumour necrosis factor (TNF)-a agents and other biologic agents: correlation with response to treatment in Crohn’s disease

Project Start Date: 1 November 2016

Completion Date: 30 April 2017

Summary: Inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), is a group of chronic, inflammatory disorders of the gastrointestinal tract. In the UK, CD and UC affect at least 115,000 and 146,000 patients, respectively. IBD may have an important impact on morbidity, quality of life, and social life of affected patients.

Anti-tumour necrosis factor (TNF)-a agents are biologic drugs targeting the potent pro-inflammatory cytokine TNF-a. Despite having revolutionised the management of IBD, anti-TNF-a agents have high costs and relevant risks, and approximately 30% patients fail to respond to treatment. Currently, there are no markers able to predict who is going to – and, more importantly, who is not going to – benefit from this treatment.

We observed that anti-TNF-a agents are degraded in a differential way by proteases, a group of enzymes which are increased in the inflamed mucosa of IBD patients. This may impair substantially their therapeutic properties.

We will study the effects of different proteases on the integrity and function of anti-TNF-a agents and other biologic drugs. We will use this information to develop serologic tests in order to identify CD patients with more likelihood to respond to a certain biologic agent.

Ultimately, we aim to identify stratification strategies prior to biologic treatment in order to optimise biologic treatment in IBD. This will have the benefit of achieving better treatment results, and of avoiding unnecessary exposure and toxicity.

Prof Thomas T MacDonald will be contributing some of the reagents and will collaborate on the serologic studies. Prof Thomas T MacDonald is Professor of Immunology and Dean for Research at Barts and The London School of Medicine and Dentistry, London, United Kingdom.

We will test the effects of proteolytic enzymes on the integrity and function of anti-TNF-a agents, namely infliximab, adalimumab and etanercept, and of other biologic agents, including vedolizumab, etrolizumab, ustekinumab, and abatacept. We will set up in vitro reaction between the proteolytic enzymes and the biologic agents and we will test the integrity (by Western blotting) and the function (by cell culture, analysis of luminescence, and flow cytometry) of the cleaved and non-cleaved biologic agents.

We will then use the results from our in vitro experiments in order to develop a serum biomarker able to predict responsiveness to biologic therapy in CD. To do so, we will evaluate the accuracy of IgG clipped by the main proteolytic enzymes involved in degradation of biologic agents as predictors of non-responsiveness to biologic therapy in CD. In particular, we will develop serologic tests for the detection of clipped endogenous IgG, and we will test them on a large cohort (n > 100) of IBD sera, in order to establish the validity of clipped IgG as predictors of non-responsiveness to biologic therapy in IBD. We will complete this part of the project via development and optimisation of new ELISA assays.

After this we will produce a final report that will disseminate our conclusions. The project will begin on 1st November 2016 with the main work being completed within 12 months. A final report will be completed by 31st December 2017.

The ultimate goal of this project is to develop a serum biomarker able to predict responsiveness to biologic therapy in IBD. Although this is unlikely to be achieved at the end of this explorative study, our data will be useful to gain insight into the main proteolytic enzymes involved in biologic agent degradation. This will form the starting point to select specific MMPs and proteases to be studied when we will be developing serologic biomarkers to identify CD patients who are more likely to respond to a certain biologic agent.

The subject of the investigation has a particularly broad relevance, as starting biologic treatment is an almost daily decision for Gastroenterologists at any hospital in UK. The technique applied for the measurement will be the ELISA assay, which is an easy, reliable and reproducible quantitative technique. The easy technique, together with the broad interest of the subject investigated and the significant pharmacoeconomic potential of the project, make us believe that there will be substantial interest for testing our findings on a larger scale with prospective clinical studies.