ATLANTA -- In a 13-1 vote, the CDC's Advisory Committee of Immunization Practices recommended that the live attenuated influenza vaccine (LAIV, sold as FluMist Quadrivalent) should not be used for the 2016-2017 influenza season -- with most members adding, "with great regret."
The committee also recommended LAIV's removal from the federally-funded Vaccines for Children program by the same vote.
Citing "evidence for poor effectiveness of LAIV in the U.S. over the last three influenza seasons," the inactivated influenza vaccine or recombinant influenza vaccine will be used for all individuals ages ≥6 months this coming influenza season.
This was an interim recommendation, as the data may be subject to change in future years. Previously, ACIP language expressed no preference for either the live or inactivated vaccine.
Preliminary data presented to the CDC in May showed that vaccine effectiveness of LAIV was 3% (95% CI -49% to 37%) against any flu virus, while the inactivated influenza vaccine effectiveness was 63% (95% CI 52%-72%) during the 2015-2016 influenza season.
Particularly concerning to the committee was data presented here, which showed that LAIV effectiveness was significantly lower in children ages 2-17, with no significant effectiveness of LAIV against influenza A(H1N1)pdm09 or B viruses. The H1N1 strain tends to disproportionately affect children.
Data from the 2014-2015 season also showed no significant effectiveness for LAIV (or the inactivated virus products) against the drifted A(H3N2) viruses.
The American Academy of Pediatrics' liaison came out strongly against LAIV. "This has major impact on pediatric practices," said David Kimberlin, MD, at the meeting. "The science simply shows that one product does not work or has not worked for the last three years."
But there were other "programmatic" concerns for such a strong recommendation. While LAIV comprises only 8% (14 million projected doses) of the total influenza vaccine supply, over half (55%) of school-based influenza vaccination programs use LAIV. There were also concerns about shortages for providers who have already ordered their influenza vaccines for the year.
"This should not depend at all on programmatic issues," said William Schaffner, MD, liaison for the National Foundation for Infectious Diseases. "The committee ought to decide if this is an ineffective or insufficiently effective vaccine, and if that is the decision, then [not using it] is the clear choice."
The committee discussed a less draconian option that it ended up rejecting, which was that LAIV not be "routinely used," except in certain situations, such as the refusal of an injectable vaccine by a parent, a shortage of age-appropriate IIV or RIV and school-based programs with no alternative vaccine. Ultimately, it was decided that this might appear as though children were getting an "inferior product" at school, and the CDC would deal with provider shortages.
The AAP already pledged its support for the decision in a statement released to the media.
"[We] will be working with CDC and vaccine manufacturers to make sure pediatricians and families have access to appropriate vaccines, and to help pediatricians who have already ordered intranasal vaccines," said Karen Remley, MD, CEO/executive director of the AAP.
Committee member Cynthia Pellegrini cast the lone dissenting vote on both recommendations. She urged the committee to delay the vote, saying that it was a lot of information to absorb on short notice to make a very important decision.
"I have not had sufficient time to consider this information fully," she said.
There was one abstention from each vote, due to conflict of interest with a vaccine manufacturer.
ACIP recommendation must be reviewed and approved by CDC's director before it becomes CDC policy. The agency usually follows ACIP recommendations. Its final position will be published in a CDC Morbidity and Mortality Weekly Report Recommendations and Reports in late summer or early fall.