RIO DE JANEIRO, BRAZIL – On Monday, August 10th, Brazil’s National Health Regulatory Agency (ANVISA) authorized the administration of the Oxford University’s vaccine second dose to volunteers of the Phase 3 study in Brazil. The period between doses is expected to be four weeks.
“For volunteers who have already undergone the trial, the second dose should have a longer interval. In this case, the term interval is due to the need to get in touch with the volunteer and mobilize them again for the booster dose,” ANVISA said in a note.
There was also a change in the age of trial participants. Now, volunteers up to 69 years of age may be selected. Formerly, the maximum age for applicants was 55. The minimum age is still 18.
UNIFESP (Federal University of São Paulo), the center conducting the research in the city of São Paulo, reports that “all volunteers who have already been vaccinated will be summoned for the second dose. The new group of volunteers to be tested, in the group up to 69 years old, will be administered two doses.”
The decision comes after a recent university study showed that the administration of a second dose of the immunizing agent induced increased antibody production in volunteers in Phase 1 and 2 clinical trials in the United Kingdom.
“The inclusion of the second dose in the research was prompted by the publication of some findings that showed that the booster dose increases the chance of immunization. ANVISA authorized the change in the research based on the safety data gathered so far. The second dose is expected to add further information to the studies and to the way in which this vaccine could be used in the future,” the agency said.
Source: Veja