FDA committee OKs new H3N2 component for US flu vaccine

The FDA’s Vaccines and Related Biological Products Advisory Committee, or VRBPAC, voted unanimously today to approve a new H3N2 component for next season’s influenza vaccines in the United States.

The VRBPAC voted to include an A/Kansas/14/2017 (H3N2)-like virus for the quadrivalent vaccine and trivalent vaccine formulations. The vote had been delayed by several weeks while the WHO advisory group that recommends vaccine viruses waited for more information to pick an H3N2 virus.

The virus is different from the one selected last year for use during the current influenza season, an A/Singapore/INFIMH-16-0019/2016-like virus.

Last month, the WHO group made recommendations for three of the four components to be included in Northern Hemisphere vaccines for 2019-2020. However, it delayed the decision on an H3N2 component “in light of recent changes in the proportions of” circulating viruses.

This week it recommended the A/Kansas/14/2017 (H3N2)-like virus, saying it performed better in tests against viruses that have been increasingly circulating in some places since November, including the U.S. H3N2 is notoriously difficult to protect against and generally portends more serious seasons when it predominates, like the one that occurred last year in the United States.

For quadrivalent vaccines, the WHO committee and VRBPAC also recommended:

A/Brisbane/02/2018 (H1N1)pdm09-like virus
B/Colorado/06/2017-like virus (B/Victoria/2/87 lineage)
B/Phuket/3073/2013-like virus (B/Yamagata/16/88 lineage)

For trivalent formulations, the recommendations included:

A/Brisbane/02/2018 (H1N1)pdm09-like virus strain
A/Kansas/14/2017 (H3N2)-like virus
B/Colorado/06/2017-like virus (B/Victoria/2/87 lineage).

With the exception of H3N2, the other strains were selected by the VRBPAC at its March 6 meeting.

The H1N1 virus is a change from the 2018-2019 influenza season’s A/Michigan/45/2015 (H1N1)pdm09-like virus strain. – by Bruce Thiel