Covid-19 vaccine: not effective for certain patients

01-06-2021 by Mirai

We know: the Covid-19 vaccine protects against Sars-CoV-2 and in particular reduces the risk of a severe form of the disease. However, certain treatments could induce a worse response to vaccination.

Millions of people have been vaccinated against covid-19, however, specialists are alert, because certain treatments for this disease would increase the risk of a serious form of Covid-19, especially prescribed for people with multiple sclerosis. And that's not all: they could also harm the effects of vaccination.

Anti-CD20 treatment: worse response to vaccination

They are called "anti-CD20". These treatments, rituximab and ocrelizumab, are said to be prescribed for about 20% of patients with multiple sclerosis, a disease of the central nervous system that affects both the brain and spinal cord. They are also used against rheumatoid arthritis or psoriasis.

However, studies have shown that these treatments put you at risk for severe Covid-19. But that's not all: patients who are prescribed may respond worse to vaccination. We see people treated with these anti-CD20s that do not produce antibodies after vaccination against Covid ", explains neurologist Jean Pelletier, from the Arsep Foundation (Helps with research in multiple sclerosis). These treatments act on B lymphocytes," the cells that make the antibodies ", specifies the neurologist.

Ongoing studies to evaluate the impact of vaccines in these patients

These findings refer to specific cases at the moment. This is the reason why the studies will focus especially on the question, with the aim of determining the real impact of the anti-Covid-19 vaccines in these patients. Among them, we find the ANRS COV-POPART cohort made up of people with a pathology that can reduce the immune response to vaccines. 600 people with multiple sclerosis will be included in this study. "We will be able to have a first response in six months," says Professor Jean Pelletier.