FLUAD

What it is

Fluad is an inactivated influenza vaccine (surface antigen), adjuvanted, suspension for injection containing influenza virus haemagglutinin as active ingredient. Each 0.5 mL dose contains influenza virus surface antigens of each of three strains representative of the influenza virus types expected to circulate in the Southern Hemisphere winter according to WHO recommendations for the 2026 season: A/Missouri/11/2025 (H1N1)pdm09-like virus, A/Singapore/GP20238/2024 (H3N2)-like virus, and B/Austria/1359417/2021-like virus, with 15 micrograms haemagglutinin per strain per dose. Fluad vaccine is prepared from virus grown in embryonated hens' eggs and inactivated with formaldehyde before purification and combination with MF59C.1, an adjuvant known to increase the immunogenicity of vaccines. MF59C.1 adjuvant is a squalene based oil-in-water emulsion.

Approved indications

— Active immunisation against influenza in persons 50 years of age and older.

Dosing overview

A single 0.5 mL dose should be administered by intramuscular injection, preferably into the deltoid muscle of the upper arm. Annual revaccination is recommended because immunity declines during the year after vaccination and circulating strains of influenza virus change from year to year.

Key safety warnings

As with all injectable vaccines, appropriate medical treatment and supervision should always be readily available in case an anaphylactic event occurs following the administration of the vaccine. Persons with a history of anaphylaxis to egg should be vaccinated only in medical facilities with staff experienced in recognising and treating anaphylaxis. Immunisation should be postponed in patients with acute febrile illness until the fever is resolved. Antibody response in patients with endogenous or iatrogenic immunosuppression may be insufficient. If Guillain-Barré syndrome has occurred within 6 weeks of previous influenza vaccination, the decision to give Fluad should be based on careful consideration of the potential benefits and risks. Commonly reported (≥10%) adverse reactions in adults 50 to less than 65 years of age who received Fluad Quad were injection site pain (47.1%), fatigue (29.5%), headache (22.2%), arthralgia (13.7%) and myalgia (13.0%). The most commonly reported (≥10%) solicited adverse events in elderly subjects were injection site pain (31.9%), fatigue (16%) and headache (12.0%). The majority of solicited reactions were reported as mild or moderate in intensity and resolved within 3 days.

Contraindications

The vaccine is contraindicated in individuals with known severe allergic reactions (such as anaphylaxis) to any component of the vaccine or a previous dose of any influenza vaccine. Persons with a history of egg allergy (non-anaphylaxis) can receive a full dose of vaccine in any immunisation setting.

PBS listing

A PBS item for prevention of influenza in patients aged 65 years and over was recommended in August 2019 but was withdrawn in July 2025.

Regulatory history

Fluad inactivated influenza vaccine was first listed on the ARTG on 2002-10-15. In March 2018, PBAC recommended listing for prevention of seasonal influenza, designated for patients aged 65 years and older. Fluad Quad was approved on 24 September 2019 for active immunisation against influenza in persons 65 years of age and older, following a positive benefit-risk assessment and no outstanding quality or nonclinical issues.