A drug used to treat inflammatory bowel disease (IBD), such as Crohn’s and ulcerative colitis, has been shown to be able to reduce the immune response against Covid-19 infection.
This drug, Infliximab, it has a dangerous side effect. According to the results of a study published in the journal “Gut”, its use would be linked to an increased risk of reinfection by coronavirus and a greater susceptibility to persistent covid.
And furthermore, if the virus becomes chronic in these patients, they could act as reservoirs for SARS-CoV-2 and promote the appearance of new variants, something that has already been suggested by some previous research that has analyzed the origin of the variants in different parts of the world. world.
The study findings CLARITY , which recruited 6,935 Crohn’s disease and ulcerative colitis patients from 92 UK hospitals between September and December 2020, showed that less than half of the people with IBD who were treated with infliximab had detectable antibodies after infection with SARS-CoV -2 infection.
Researchers from the Royal Devon and Exeter NHS Foundation Trust and the University of Exeter School of Medicine (UK), say that an impaired immune response can increase susceptibility to recurrent Covid-19 and help drive the evolution of new variants of SARS-CoV-2.
However, they add, they encourage people to continue taking their medications, as the risk of Covid-19 remains very low.
Thus, they advise that patients treated with infliximab have a closer monitoring after receiving the Covid-19 vaccine to ensure that they acquire a good antibody response to protect against infection.
Infliximab is part of the tumor necrosis factor (anti-TNF) inhibitors, drugs that suppress the production of an inflammatory protein involved in the development of various conditions, such as ulcerative colitis and Crohn’s.
About two million people worldwide receive anti-tumor necrosis factor (anti-TNF) drugs, including infliximab. The drugs anti-TNF They are effective treatments for immune-mediated inflammatory diseases, but by suppressing the immune system, they can reduce the effectiveness of the vaccine and increase the risk of serious infections.
Thus, The authorities in the United Kingdom recommend that people who take these drugs are better protected in the pandemic through strict social distancing measures, and some, depending on the severity of their condition, were recommended to protect themselves against Covid-19.
In the study, the researchers compared antibody responses to SARS-CoV-2 in patients treated with infliximab with an alternative drug, vedolizumab, which blocks inflammatory cells entering the intestine without reducing immune responses to infections or vaccines.
Rates of Covid-19 infection and hospitalizations were similar between infliximab and vedolizumab treated patients. However, those treated with infliximab were much less prone to later having a positive antibody test.
Therefore, the researchers write, these findings cannot be explained solely by differences in acquisition or severity of infection. Rather, infliximab appeared to directly influence antibody responses to infection.
Consistent with this idea, positive antibody test rates were lower in participants who were also taking other medications that suppress the immune system.
The studio director, Tariq Ahmad, notes that the poor antibody responses seen in patients treated with infliximab “increase the possibility that some patients will not develop protective immunity after Covid-19 infection, and may be at increased risk of reinfection.” What we still do not know, he adds, “is how the use of anti-TNF drugs will affect antibody responses to vaccination.”
The work is based in an observational study, Therefore, the authors emphasize that a clear cause cannot be established as to why this reduction in the immune response against COVID-19 occurs. The researchers also acknowledge other limitations, such as that a weaker immune response does not automatically translate into an increased risk of infection and that only one drug has been studied. anti-TNF.
However, they suggest that a weakened antibody response has many implications. For example, these patients may be more susceptible to developing persistent COVID-19 and chronic colonization of the virus in the nose and throat. “This could act as a reservoir driving persistent transmission of the coronavirus and new variants of SARS-CoV-2,” they write.
For Sarah Sleet, CEO of Crohn’s & Colitis UK, “The CLARITY results are an important first step in understanding how different drugs for Crohn’s disease and colitis affect a person’s response to coronavirus. At this stage, the key message is that they should continue to take their medications and receive the vaccine.