Vaccine Info

Fluad Quadrivalent Influenza Vaccine

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Last reviewed
October 19, 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.

New Jersey-based Seqirus (CSL.AX) is a leader in the fight against influenza with an innovative portfolio of influenza products.

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.

This adjuvanted inactivated influenza vaccine (IIV-Adj) is currently authorized for use in Canada.

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

Fluad Pediatric Influenza Vaccine Description

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 egg-based 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.

On July 27, 2021, Gregg Sylvester, M.D., Chief Medical Officer at Seqirus, stated in a press release, “With our rich history and exclusive focus on influenza, we know that influenza vaccination can save lives and is an important step we can take to help protect ourselves, our loved ones and our communities. A continued focus on influenza vaccination is critically important because, while rates of influenza were generally low last season, we cannot assume this will be the case during the coming year, and we need to be prepared."

Fluad Influenza Vaccine Dosage

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

Fluad Influenza Vaccine and COVID-19 Vaccines

The US Centers for Disease Control and Prevention (CDC) previously issued interim clinical considerations stating that 'COVID-19 vaccines and other vaccines, including influenza vaccines, can be administered without regard to timing. And the annual influenza vaccination is recommended for all persons aged 6 months and older who do not have contraindications. 'Providers should be aware of the potential for increased reactogenicity with coadministration and should consult the CDC for updated guidance as more information becomes available. If coadministered, COVID-19 vaccines and vaccines that might be more likely to cause a local reaction (e.g., aIIV4 or HD-IIV4) should be administered in different limbs, if possible.'

'No data are currently available concerning coadministration of currently Authorized COVID-19 vaccines and influenza vaccines,' stated Lisa Grohskopf, M.D., MPH, CDC's ACIP vaccine committee presentation (slide #14) on June 24, 2021.

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

October 19, 2021 - New real-world evidence (RWE) was presented by Seqirus at the global International Society for Influenza and other Respiratory Virus Diseases (ISIRV). Data from two retrospective cohort analyses supported the effectiveness of adjuvanted trivalent seasonal influenza vaccines (aTIV) for older populations (aged ≥65). Fewer IRMEs were documented in people vaccinated with aTIV compared to QIVe, and aTIV was comparable to high-dose trivalent influenza vaccines (TIV-HD) in preventing IRMEs.

October 7, 2021 - The UK's Respiratory Datamart, reported there were 8 influenza-positive samples detected in week 39.

September 29, 2021 - At the virtual IDWeek 2021 Seqirus (ASX:CSL) announced real world data supporting the effectiveness of both cell-based and adjuvanted seasonal influenza vaccines from two studies conducted during the 2019/2020 influenza season in the U.S. 

September 29, 2021 - Pfizer Inc. (NYSE:PFE) announced “Both PREVNAR 20 and the influenza vaccine are important for helping protect adults against pneumococcal pneumonia and the flu respectively; however, vaccination rates decline when someone needs to make multiple appointments to receive these vaccines,” said Luis Jodar, Ph.D., Senior Vice President and Chief Medical Officer, Pfizer Vaccines. “The results of this trial supports current CDC clinical guidance allowing coadministration during a single doctor or pharmacy appointment, so that more adults are able to help protect themselves against both of these respiratory diseases.”

September 18, 2021 - The CDC weekly Fluview report continues to show very low circulation of the influenza virus.

September 11, 2021 - During week 36, 2.3% patient visits reproted to the ILINet were due to ILI, according to the CDC.

September 4, 2021 - The U.S. CDC reported on the 2020-2021 Influenza season, ending 9/4/2021.  The percentage of patient visits for Influenza-like Illness remains below the national baseline.

August 13, 2021 - Nationwide during week 31, 2.0% of patient visits reported through ILINet were due to ILI. Although increasing, the percentage of patient visits for ILI remains below the baseline of 2.6% nationally. One region (Region 7) is at its region-specific baseline while the remaining regions are below their baselines. Influenza virus circulation remains low; therefore, increases in ILI activity are likely due to increased circulation of other respiratory viruses.

July 26, 2021 - Global Influenza Vaccines Market Report 2021-2027. In November 2020, Seqirus announced its plans to construct a new world-class biotech manufacturing facility in Australia to supply influenza vaccines to Australia and the rest of the world.

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