The third dose of CoronaVac, vaccine from Butantan and the chinese pharmaceutic Sinovac, demonstrated to be efficient to recover the immune response on immunosuppressed individuals that decreased six months after the second dose and, especially, by the use of medicines that affects the immune system, affirmed the clinical director of the Clinical Hospital from the Medicine School of University of São Paulo, Eloisa Bonfá. The declaration was made during the CoronaVac Symposium, a free and online event that discusses the main studies and discoveries regarding the immunizing.
Eloisa’s team, that studies the effects of vaccines anti-Covid on patients with autoimmune rheumatic diseases, evaluated the durability of the vaccine protection six months after the second dose and the protection in part of these patients (597 immunosuppressed individuals in comparison with 200 volunteers of the control group) after the third dose, a total of 910 patients were analyzed.
“There was an important decrease of IGG, GMT and neutralizing antibodies levels and I would like to call attention to say that it happened with other vaccines as well, such as the RNA, with more than four times the decreasing of IGG after six months on health professionals and on the male gender”, said.
According to the researcher, the booster dose was preponderant to recover the protection. “With the booster dose, there was a strong general response, with 93% of positivity for IGG and 81% for neutralizing antibodies and a very impressive and high level of GMT. The third dose was efficient to recover the immune response in this population.”, she affirmed.
Medication affects the vaccine response
According to the researcher, the use of specific medicines to contain symptoms of the autoimmune rheumatic diseases is the main factor of interference on the immune response among the immunosuppressed individuals.
“With this distinction, we have 70% of responses when we consider those patients without exposure. If we include seropositives [individuals that already had Covid-19], we have almost 80% of response, taking on account that we use theraphys of immunosuppression on a higher quantity”, she complemented.
When her research team studied specifically patients with lupus, the response to CoronaVac was similar to the one seen on vaccines with Messenger RNA, explained Eloisa. “We had the same frequency of seropositivity of 70% IGG that they had with the vaccines of Messenger RNA. With that, we believe that we have arguments to say that the vaccines are not different [in this public], but the medication that the patients use is what makes the difference”.
The study evaluated 910 patients with autoimmune rheumatic diseases (DRA) that were not exposed to the coronavirus and are on treatment at the Clinical Hospital. The patients were evaluated for 40 days until they completed the vaccinal scheme with three doses of CoronaVac. Only three of them were hospitalized 10 days after the second dose and any other hospitalization was declared during the other days.
Bonfá highlights that the study was realized in the middle of the second wave of the pandemics in São Paulo, where the Covid-19 cases had increased 45% in the city. “However, among the volunteers of the study there was a reduction of 81% of cases during the period of the complete response of the vaccine”.