Anvisa (National Health Surveillance Agency) authorized, on Tuesday (28), the Butantan Institute to start the final tests on humans of a new vaccine (tetravalent) against the flu. The vaccine provides additional protection against a type of influenza virus.
The objective of this phase of the research is to evaluate the safety, immunogenicity (ability to stimulate the production of antibodies) and the consistency of the immune response.
The Butantan Institute is the only supplier of flu vaccines that are used by SUS throughout Brazil.
Vaccines are trivalent. The formulation varies according to the viruses that circulate each year, but basically includes two strains of influenza A and one strain of influenza B. The definition is made by the WHO (World Health Organization).
Currently, it is composed of the fragmented and inactivated influenza virus, with the A strain (H1N1 and H3N2) and the B strain (Victoria and Yamagata lineage).
Butantan now wants a vaccine along the lines of those already used in the private network, with two strains of influenza A and another two of influenza B.
The new formulation also includes the influenza B virus (Victoria lineage – TIV-V-IB).
“In this way, it is expected to obtain a vaccine analogous to the trivalent one, but with additional protection against a second B strain, determined seasonally by the World Health Organization”, says Anvisa in a statement.
In last year’s campaign, the Ministry of Health distributed 80 million doses.
This year, the flu immunization schedule for priority groups should start in April, but still with the trivalent vaccine.
The current study of the tetravalent vaccine intends to include approximately 7,000 participants in São Paulo, Minas Gerais, Rio Grande do Sul, Ceará, Sergipe and Pernambuco.
This last phase of the study, before the application for registration at Anvisa, should last 12 months, with the possibility of extension.