Cardiff and Vale UHB contributes to IBD and COVID-19 study

Cardiff and Vale University Hospital Board (UHB) has contributed to a research study which has revealed new evidence that common inflammatory bowel disease (IBD) treatment is linked to patients producing a reduced COVID-19 antibody response.

The CLARITY study has been delivered by the Cardiff and Vale Research Delivery Team, through the Adult IBD team at University Hospital Llandough and at the Children and Young Adult’s Research Unit.

Led by gastroenterologists at the Royal Devon and Exeter NHS Foundation Trust and the University of Exeter Medical School and supported by Crohn’s and Colitis UK and the UK National Institute for Health Research (NIHR), the study’s findings indicate that the commonly-prescribed IBD drug infliximab limits the immune system response to COVID-19 infection, potentially increasing the risk of reinfection.

Dr Dharmaraj Durai, Consultant Gastroenterologist at the University Hospital of Wales, said: “I am delighted with the Health Board’s contribution to this national study on SARS cov-2 infection and antibody response in patients with Inflammatory bowel disease.

“This study of such importance and relevance has provided us with valuable insights into managing patients with Colitis and Crohn's disease during the COVID-19 pandemic. It is a credit to both our Adult IBD team and the Children and Young Adult’s Research Unit, as well as the 66 patients that we recruited to this trial. Collectively, they have all helped to provide important, in-depth information that will greatly improve treatment as we move forward.”

The study recruited 6,935 patients with Crohn’s disease and ulcerative colitis from 92 UK hospitals between September and December 2020. Among the participants were children recruited through Cardiff and Vale UHB’s Children and Young Adult’s Research Unit.

Amar Wahid, Consultant Paediatric Gastroenterologist at Cardiff and Vale UHB, said: “The inclusion of paediatric gastroenterology patients from South Wales has broadened the scope of this important study and demonstrated the value of close collaboration with adult clinical and research teams. The families enrolled were very keen to contribute and we are grateful for the role they have played in demonstrating these new findings in the context of the COVID pandemic.”

Paediatric Research Nurse Specialist Zoe Morrison added: “The design of the CLARITY trial to include both paediatrics as well as adult patients is refreshing and it has been a pleasure to work with children and their families to help contribute to these important findings in one of our vulnerable groups.

“We hope that the design to include both paediatric and adult participants in the same trial continues in the future and we can strengthen our collaborative ties between the Health Board’s Clinical Research Facility and Children and Young Adult’s Research Unit.”

Around 500,000 people across the UK live with Inflammatory bowel disease (IBD), of which ulcerative colitis and Crohn’s disease are the two main forms. At the start of the COVID-19 pandemic, the UK Government warned that patients taking TNF inhibitors, or anti-inflammatory medicines, could be at higher risk of complications from coronavirus. All were advised to follow strict social distancing measures, and some with severe conditions were advised to shield.

In the CLARITY study, researchers compared antibody responses to SARS-CoV-2 in patients treated with infliximab to those taking an alternative medication, vedolizumab, which blocks inflammatory cells entering the gut without reducing immune responses to infections or vaccinations. 

While rates of COVID-19 infection and hospitalisations were similar between patients treated with infliximab and vedolizumab, those treated with infliximab were far less likely to subsequently have a positive antibody test. Rates of positive antibody tests were lowest in participants who were also taking other drugs that suppress the immune system.

The CLARITY study lead, Professor Tariq Ahmad, of the University of Exeter Medical School, recommended careful monitoring of infliximab-treated patients who have been vaccinated against COVID-19, to ensure they present a strong enough antibody response to ward off the infection. The study will continue to follow participants for 40 weeks to further investigate the impact of immunosuppressive drugs on immunity to COVID-19.

The full research paper, “Anti-SARS-CoV-2 antibody responses are attenuated in patients with IBD treated with infliximab”, is published in GUT and is available to read here: https://gut.bmj.com/lookup/doi/10.1136/gutjnl-2021-324388.