An adjuvant is any compound used in vaccines to boost the immune response of vaccinated people.
Fluad is a trivalent vaccine, which means it is produced from three flu virus strains. It also contains the adjuvant MF59, which is made with squalene oil, a naturally occurring substance found in people, animals and plants, the FDA said in an agency news release.
The vaccine’s approval is based on an international clinical trial of more than 7,000 people, aged 65 and older, who received either Fluad or Agriflu, another trivalent seasonal flu vaccine. Both vaccines triggered comparable immune responses.
The study also concluded that Fluad was safe. The most common side effects were injection site pain and tenderness, muscle aches, headache and fatigue.
“Fluad provides another alternative for a safe and effective influenza vaccine in people 65 years of age and older,” Dr. Karen Midthun, director of the FDA’s Center for Biologics Evaluation and Research, said in the news release.
“Immunizing individuals in this age group is especially important because they bear the greatest burden of severe influenza disease and account for the majority of influenza-related hospitalizations and deaths,” she added.
In recent years, people aged 65 and older have accounted for 80 percent to 90 percent of seasonal flu-related deaths and 50 percent to 70 percent of flu-related hospitalizations in the United States, according to the FDA.
Fluad — made by Novartis — has been used in Italy since 1997 and is currently approved in 38 countries, the FDA said.