An expert panel on Wednesday recommended not using the influenza vaccine's nasal form for the upcoming flu season, citing its lack of effectiveness over the past three years. AstraZeneca, the vaccine's manufacturer, generated more than $200 million in sales from it in fiscal 2015. The company estimates it will lose around $80 million.
The advice also marks an about-face for the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices, which as recently as the 2014-15 flu season recommended the nasal spray as the preferred form of the flu vaccine for children ages 2 to 8. The decision was based on data at the time that showed the spray to be more effective than the shot in children ages 6 and 59 months.
Last year, the advisory committee backed off its endorsement of the nasal spray a bit when it gave no preference to any vaccine type after data from the 2013-14 season found the product had no “measurable effectiveness” for young children against the H1N1 strain of the flu, while the injected form of the vaccine was 60% effective.
The panel's latest recommendation advises that the nasal spray vaccine, which is branded as FluMist, should not be used in any setting. Data on the spray's effectiveness in children between the ages of 2 and 17 showed that during the 2015-16 season FluMist had an efficacy rate of about 3%, which according to the CDC meant it statistically provided no real protective benefit.
By comparison, the flu shot's effectiveness was around 63% last season among young people. The spray was also found to have performed poorly during the 2013-14 and 2014-15 flu seasons.
Two years ago was a particularly bad time for all forms of the flu vaccine, when a mutation in the virus' dominant strain caused that season's overall batch of vaccines to be only 23% effective, but data showed the nasal spray was even less effective than the flu shot.
FluMist is the only nasal flu vaccine available on the market. The Food and Drug Administration approved its use in 2003 and since that time more than 116 million doses have been distributed globally. The nasal spray was projected to make up about 8% of the total flu vaccine supply in the U.S. for the upcoming season.
In all, between 171 million and 176 million doses of flu vaccine are projected to make up the total supply for the 2016-17 flu season, of which 14 million doses of FluMist were expected to be available.
Given that the nasal spray makes up a small share of the total supply, the absence of FluMist this season is not expected to cause large-scale disruptions in vaccine distribution, but it is possible local shortages could occur as healthcare providers that have pre-ordered doses of FluMist look for other options, according to Dr. Henry Bernstein, a spokesman for the American Academy of Pediatricians.
“It is hoped that all children ages 6 months and older will still be able to receive the influenza vaccine," Bernstein said. The group released a statement Wednesday supporting the advisory committee's recommendation.
Bernstein acknowledged the possibility that losing a form of the vaccine that allowed children to receive a spray in the nose in lieu of a shot could lower vaccination rates. But he said the American Academy of Pediatricians planned to work with vaccine manufacturers to ensure there were adequate supplies of the injected form. The academy also planned to conduct outreach with families and providers to help explain why the nasal spray is not recommended.