High-dose influenza vaccine is 24% more effective than the standard-dose vaccine in protecting persons ages 65 and over against influenza illness and its complications, according to a Vanderbilt-led study published today in the New England Journal of Medicine (NEJM).
Known as the Fluzone High-Dose vaccine, and made by Sanofi Pasteur, the inactivated influenza vaccine contains four times the amount of antigen that is contained in the standard-dose Fluzone vaccine.
Study authors said about one-in-four breakthrough cases of influenza could be prevented if the high-dose vaccine were used instead of the standard-dose vaccine.
The multi-center study enrolled 31,989 participants from 126 research centers in the US and Canada during the 2011-2012 and 2012-2013 influenza seasons in the Northern Hemisphere in order to compare the high-dose trivalent vaccine versus the standard-dose trivalent vaccine in adults over 65 years of age.
Researchers concluded that the high-dose vaccine is safe, induces significantly higher antibody responses, and provides superior protection against laboratory-confirmed influenza illness compared to standard dose among persons over 65 years of age.
Study data also indicated that the high-dose vaccine may provide clinical benefit for the prevention of hospitalizations, pneumonia, cardio-respiratory conditions, non-routine medical visits, and medication use.
“The study was done to see if using a high-dose vaccine protected older adults better than the usual vaccine. Until this trial came out we didn’t know if it was going to be clinically better or not and now we know it is better,” said lead author Keipp Talbot, M.D., assistant professor of Medicine, who served as coordinating investigator for the more than 100 study sites.
“Fluzone High-Dose vaccine is the only influenza vaccine in the US that is designed specifically to address the age-related decline of the immune system in older adults,” said David P. Greenberg, MD, vice president, Scientific & Medical Affairs, and chief medical officer, Sanofi Pasteur US.