Vaccine Info

Fluad Quadrivalent Influenza Vaccine

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Last reviewed
July 16, 2021

Fluad Quadrivalent Influenza Vaccine Description

Fluad consists of an inactivated, quadrivalent influenza virus antigen produced in eggs and an oil-in-water emulsion adjuvant, MF59. Fluad is the first FDA-approved seasonal flu shot that contains an adjuvant, which is an immune-enhancing ingredient.

On November 24, 2015, the U.S. Food and Drug Administration sent an approval letter authorizing the introduction or delivery of Fluad into interstate commerce. 

The immune-enhancing ingredient in Fluad is an oil derived from squalene. Squalene is a naturally occurring substance found in humans, animals, and plants. Adults aged 65 and older with an aging immune system might have a lower immune response to traditional flu vaccines than younger adults.

Squalene, the immune-enhancing ingredient, is proven to provide a robust immune response to help adults' immune systems of 65 and older recognize and respond to the flu virus.

For 2021-2022, the FDA has recommended a quadrivalent (four-component) egg-based vaccine that includes these components.

Fluad Trivalent Influenza Vaccine Description

Fluad (aTIV) consists of an inactivated, trivalent influenza virus antigen produced in eggs and an oil-in-water emulsion adjuvant, MF59. Adding MF59 adjuvant to an influenza vaccine is designed to enhance the immune response to the influenza strains contained in the vaccine in adults 65 years and older.

For 2021-2022, the FDA has recommended the trivalent (three-component) egg-based vaccine that includes these components.

Fluad Pediatric Influenza Vaccine Description

The adjuvanted inactivated influenza vaccine (IIV-Adj) currently authorized for use in Canada is Fluad trivalent subunit IIV containing the adjuvant MF59, an oil-in-water emulsion composed of squalene as the oil phase that is stabilized with the surfactants polysorbate 80 and sorbitan triolate in citrate buffer.

Fluad Pediatric® contains 7.5 µg HA per strain administered as a 0.25 mL dose by IM injection for children 6-23 months of age is currently authorized in Canada.

Fluad Influenza Vaccine Indication

The Fluad vaccine is indicated for active immunization against influenza viruses caused by influenza virus subtypes A and type B in the vaccine. Fluad helps protect against the same flu strains as other seasonal flu shots, but it has something they don’t have: an immune-enhancing ingredient that can help provide a strong immune response to the flu in adults 65 and older.

Seniors with an aging immune system might have a lower immune response to traditional flu vaccines than younger adults.

Fluad vaccine has an extensive clinical legacy, with millions of vaccine doses distributed and licensure in 30 countries since it was first approved in 1997.

Fluad Influenza Vaccine Dosage

Fluad is administered as an intramuscular injection in adults 65 years of age and older.

Fluad Influenza Vaccine Adverse Events

Some adverse events (reported after regular flu vaccines) were reported more frequently after vaccination with FLUAD. During clinical studies, the adverse events were mild to moderate and temporary: pain, redness at the injection site, headache, muscle aches, and malaise.

People should not get FLUAD or FLUAD QUADRIVALENT if they have had a severe allergic reaction to any of the ingredients in the vaccine in the past, including egg protein, or a severe allergic reaction to a previous influenza vaccine.

Fluad Influenza Vaccine News

June 14, 2021 - Seqirus announced that the company co-authored the first study to demonstrate the safety, immunogenicity, and efficacy profile of the Novavax COVID-19 vaccine candidate when co-administered with a seasonal influenza vaccine. The data is now available on medRxiv ahead of peer-review publication.

June 3, 2021 - A systematic review and meta-analysis study was to determine the effectiveness of seasonal MF59-adjuvanted trivalent/quadrivalent influenza vaccine (aTIV/aQIV) relative to no vaccination or vaccination with standard or high-dose egg-based influenza vaccines among people ≥65 years old. Results: The MF59-adjuvanted trivalent influenza vaccine was effective in preventing influenza in adults 65 years of age or older. Compared to standard-dose egg-based QIV and TIV, aTIV was significantly more effective in preventing influenza-related medical encounters (illnesses or hospitalizations). The effectiveness of aTIV was comparable to high-dose TIV in preventing influenza-related medical encounters. High heterogeneity was observed for all relative VE analyses with seasonal variation, distinct populations, and diverse outcomes potentially playing a role in the variability of the effect sizes coupled with precise effect estimates. As such, further research is needed to confirm the findings for relative VE.

April 20, 2021 - Real-World-Evidence published in the journal Clinical Infectious Diseases indicate that Seqirus' aTIV was more effective in reducing influenza-related medical encounters compared with standard egg-based quadrivalent influenza vaccine (QIVe) and high-dose trivalent influenza vaccine (TIV-HD) among adults 65 years and older during the 2017/18 and 2018/19 U.S. influenza seasons. "This retrospective cohort study, which includes 10.6 million vaccinated U.S. individuals, demonstrates the value that RWE can provide by illustrating the effectiveness of influenza vaccines in real-world settings," said Constantina Boikos, lead study author and Senior Manager, Center for Outcomes Research & Evaluation at Seqirus.

January 5, 2021 - Adjuvanted influenza vaccine and influenza outbreaks in U.S. nursing homes: Results from a pragmatic cluster-randomized clinical trial. Among 777 facilities, the adjuvant group experienced a 17% reduction in suspected and laboratory-confirmed influenza outbreaks, reported Vincent Mor, Ph.D., a renowned nursing home researcher. The estimated reduction in outbreaks rose further — to 22% for laboratory-confirmed outbreaks — when the researchers adjusted for facility-level vaccination rates and resident characteristics.

December 14, 2020 - Seqirus Presents New Late-Breaking Data at ESWI 2020 Highlighting Benefits of MF59®-Adjuvanted Seasonal Influenza Vaccine. "Adults age 65 years and older are at higher risk for complications from seasonal influenza. At Seqirus, we're focused on utilizing advanced technology like the MF59® adjuvant to potentially offer better protection against influenza for those most vulnerable, like adults in this age group," said Gregg Sylvester, MD, Chief Medical Officer at Seqirus.

October 25, 2020 - Fluad on Par With High-Dose Flu Vax in High-Risk Seniors.

September 21, 2020 - Seqirus announced the publication of new real-world evidence (RWE) that demonstrated an MF59® adjuvanted, trivalent influenza vaccine (aTIV) was more effective than a standard-dose non-adjuvanted trivalent seasonal vaccine in preventing influenza-related medical office visits and hospitalizations in adults 65 years and older during the 2017/18 U.S. influenza season.

February 24, 2020 - Seqirus Receives FDA Approval for FLUAD QUADRIVALENT for Adults 65 Years and Older

Fluad Influenza Vaccine Clinical Trials

Seqirus continues to participate in clinical trials for its family of Fluad influenza vaccines.

Clinical Trials