The researchers of FM-USP (The University of São Paulo School of Medicine) found that certain types of drugs used to treat patients with autoimmune rheumatic diseases, such as rheumatoid arthritis, have the ability to reduce the immune response of vaccines against covid- 19.
In the study, the results were published in the journal Natural Medicine, patients vaccinated with CoronaVac, produced in Brazil by the Butantan Institute, were evaluated. It is still necessary to test whether the same effect occurs with vaccines from other laboratories.
Conducted with support from FAPESP and B3 – Stock Exchange, the research aimed to assess the safety and effectiveness of CoronaVac in patients with nine types of autoimmune rheumatic diseases.
Based on the results, the authors are developing new vaccination strategies for these patients, which include suspending treatment one or two weeks before CoronaVac application and continuing it after vaccination, with the aim of improving the immune response.
“We have noticed that some drugs, such as glucocorticoids, in addition to immunosuppressants, such as methotrexate and mycophenolate mofetil, and some biologicals reduce the immune response in these patients,” said Eloísa Bonfá, professor at FM- USP and study coordinator, at the FAPESP Agency.
“Based on this observation, we began to study several vaccination techniques, such as suspending the drug with mofetil for one week and methotrexate for two weeks before applying the vaccine,” Bonfá said.
According to the researchers, due to the lack of immunity, patients with immunosuppressed ̵1; which includes not only those with autoimmune diseases, but also those undergoing treatment for cancer, transplants and human inhabitants immunodeficiency virus (HIV), among others – is at high risk of having a reduced response to vaccines. Moreover, autoimmune rheumatic diseases may increase the tendency to thrombosis.
To assess whether vaccines against COVID-19 are effective and safe for these people, FM-USP researchers followed 910 adult patients, who were treated in the rheumatology laboratory of the Hospital das Clínicas, FM -USP, up to 40 days after receiving the second dose of CoronaVac.
“Patients are monitored in a tertiary center and, therefore, have more severe cases of rheumatoid and psoriatic arthritis, in addition to axial spondyloarthritis and other systemic autoimmune rheumatic diseases, such as lupus erythematosus, vasculitis, Sjögren’s syndrome, systemic sclerosis , inflammatory and idiopathic myopathies antiphospholipid syndrome, “Bonfá explains.
Patient blood samples for identification of antibodies to SARS-CoV-2 were analyzed then, after 28 days and after six weeks of complete vaccination with CoronaVac. The results were compared with 182 people without autoimmune diseases or not taking immunosuppressants, who formed a control group.
The results of the studies indicated that the vaccinating agent was able to induce seroconversion to IgG-type antibodies in 70.4% in patients with autoimmune rheumatic diseases versus 95.5% in the control group.
“We saw a reduction in the immune response in these patients compared to the control group, which we consider moderate and within the standards established by WHO [Organização Mundial de Saúde]”, said Bonfa.
“A rate of 70.4% serological response is very important for people who have reduced immunity or who take drugs that reduce immunity”, he evaluates.
Up to ten days after the first dose of vaccination, if the vaccine response was incomplete, 33 of the study participants had COVID-19. And 40 days after this period, when the immune response to vaccination had already developed, only six patients became ill. Only four individuals needed to be hospitalized and no deaths were registered.
The decrease in cases of infection among the participants, from 33 to only six, occurred inversely to the top of the records of new SARS-CoV-2 infections in São Paulo, which at the same time had an increase of 45 %, Bonfá said.
“The observation that ten days after the second dose there is a significant reduction in cases shows that the vaccine seems to have very good effectiveness even in this population of immunosuppressed patients, who are more likely to have an infection”, said the researcher.
“It reinforces the recommendation for these patients to be vaccinated”, he stressed.
According to the researchers, in addition to presenting an increased risk of contracting infectious diseases and evolving into a serious condition, immunosuppressed patients have a higher incidence of comorbidities, such as hypertension and overweight, which risk factors for covid-19. Therefore, they should be prioritized from the beginning of the vaccination campaign against the disease.
In addition, immunosuppressed patients have more difficulty “clearing” the virus from the body compared to healthy people, which favors the development of mutations.
“Prioritizing the vaccination of this group is important not only for them, but also for the population in general, because in this way it is possible to reduce the risk of occurrence of the mutation”, he said.