High-Dose Flu Shot Benefits Older Patients, Study Finds


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Fall allergy madness may have only just begun, but the dreaded flu season — which can start as early as October, according to the Centers for Disease Control and Prevention (CDC) — is hot on its heels. And this time around, with it comes some good news for folks 65 and over: The recently introduced Fluzone High-Dose vaccine is 24.2 percent more effective than the standard version in preventing flu in that age group, a new study has found.

The most exciting part is finally being able to show superior protection against influenza,” David Greenberg, lead researcher and chief medical officer for Sanofi Pasteur, the maker of the Fluzone vaccine, told Yahoo Health. “And the most surprising finding is that there’s great benefit in preventing secondary effects of the flu, such as hospitalizations, pneumonia, and cardiorespiratory complications. We weren’t expecting that.” Also with the findings comes a new hope, he added: to begin looking at clearing the High-Dose option for use by those younger than 65, too.

Related: The Medical Tests Some People Over 65 May Not Need

Fluzone High-Dose vaccine is an inactivated influenza vaccine that contains four times the amount of antigen (an agent that stimulates the immune system) than standard-dose flu vaccines. Although it was approved in 2009 for use in adults 65 and older in an aim to compensate for seniors’ declining immune systems, the Food and Drug Administration gave that approval with a request to the manufacturer: Deliver more proof of effectiveness. And now, Greenberg said, it has. “There were prelicensure [safety] studies that showed a superior antibody response,” he said. “But this is the first to demonstrate an actual clinical benefit.”

For the study, published in August in the New England Journal of Medicine, researchers compared the vaccine’s efficacy in a large-scale trial that spanned two influenza seasons and enrolled nearly 32,000 participants age 65 and older — a population in which about 90 percent of all flu-caused deaths occur, Greenberg noted. In addition to the benefits, the research also found that about nine percent of people receiving either vaccine dose experienced side effects, including localized site reactions or congestion, with slightly fewer side effects among those who had the High-Dose vaccine. Also, noted the study’s press materials, “There were a total of 83 deaths in the Fluzone High-Dose vaccine group and 84 deaths in the standard-dose Fluzone vaccine group during the six-month surveillance period, none of which were considered by the investigators as related to vaccination.”

Related: ‘Unacceptably Low’ Numbers of Adolescents Getting HPV Vaccine, CDC Reports

At this point, Greenberg said, if a physician chose to give the High-Dose vaccine to a patient younger than 65, “that would be considered off-label,” and not advisable, since the study looked only at the older population. But that could change in the future, he said. “It might in fact be beneficial for those under 65,” he said, since everyone’s immune system begins to decline gradually with age. Studies on a younger age group, he noted, “are certainly something the company is considering.”

Some other facts about Fluzone High-Dose to keep in mind as we edge toward flu season:

•The shot is widely available at doctor’s offices and at pharmacies such as CVS.

•As with all flu vaccines, the CDC does not recommend Fluzone High-Dose for anyone who has had a severe reaction to a flu vaccine in the past.

•It’s only one of five flu vaccines produced by Sanofi Pasteur under the brand name Fluzone. Other brands on the market besides Fluzone include Fluarix by GlaxoSmithKline, Fluvirin by Novartis, and FluBlok by Protein Sciences. Differences range from the amount of egg protein (which some people are allergic to) or thimerosal (a controversial mercury-based preservative) to how the vaccine is administered — intramuscularly, intradermally (via longer needle), or intranasally (through a nose spray).