In 2015, the FDA approved Fluad, the first adjuvanted trivalent flu vaccine containing a squalene oil adjuvant (MF59). This vaccine was approved for fast track licensure by the FDA, despite limited data on safety and immunogenicity, with approval based on a single clinical trial of about 1,000 healthy adults over the age of 65. This vaccine became available for the first time to adults over the age of 65 for the 2016-2017 flu season. In 2022, the CDC preferentially recommended this vaccine for all individuals 65 years of age and older.
