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New Data Demonstrate that FLUAD® (Influenza Vaccine, Adjuvanted) Significantly Reduces Hospitalization Risk for Adults 65+ Living in U.S. Nursing Homes Compared to Standard Trivalent Influenza Vaccine

Study highlights lower hospitalization rates in adults 65 years and older living in U.S. nursing homes who received an adjuvanted influenza vaccine versus standard trivalent influenza vaccine (TIV)

SUMMIT, N.J., Dec. 9, 2019 /PRNewswire/ -- Seqirus announced today results from a prospective, cluster-randomized trial led by a team of researchers from Brown University that showed FLUAD®, an adjuvanted trivalent influenza vaccine (aTIV), was more effective than standard non-adjuvanted trivalent influenza vaccine (TIV) in reducing the risk of all-cause hospitalizations, as well as hospitalization for influenza and pneumonia, in adults 65 years and older living in United States (U.S.) nursing homes during the 2016/17 influenza season.1 These findings were presented at the recent National Foundation for Infectious Diseases (NFID) 2019 Clinical Vaccinology Course (CVC), which took place in Washington, D.C.

In the study, 823 nursing home facilities were randomized to offer an aTIV versus a standard non-adjuvanted TIV influenza vaccine as part of standard of care for 50,012 residents age 65 years and older—FLUAD (n=24,926 residents) or TIV (n=25,086 residents)—during the 2016/17 influenza season. A portion of residents (15%) elected not to accept either vaccine. The goal of the study was to evaluate the potential role of FLUAD in reducing the risk for hospitalization in this population. Researchers reported that in their intent-to-treat analysis, residents offered FLUAD experienced 6 percent fewer hospitalizations from all causes compared with those who received a standard non-adjuvanted TIV (adjusted hazard ratio 0.94, 95% CI: 0.89, 0.99, p=0.02). Moreover, FLUAD was 20 percent more effective than TIV in reducing the rate of hospitalization for influenza and pneumonia (adjusted hazard ratio 0.80, 95% CI: 0.66, 0.98, p=0.03).1

"This study highlights that, even in adults 65 years and older sufficiently impaired to require nursing home care, adjuvanted seasonal influenza vaccine can help reduce the risk of hospitalization," said Dr. Stefan Gravenstein, MD, MPH, Professor of Medicine and Health Services, Policy and Practice at the Brown University School of Public Health and lead study author. "These data are particularly significant given the low vaccine effectiveness observed in the study season overall."

This reduced hospitalization risk was observed during a season characterized by the predominance of the A/H3N2 influenza virus, which was subject to antigenic drift and egg-adaptation.2,3 The Centers for Disease Control and Prevention (CDC) reported the adjusted overall vaccine effectiveness for the 2016/17 influenza season was 21 percent for influenza A/H3N2 viruses in adults 65 years and older, and 20 percent overall across all strains.2,4

"These data build on the growing body of evidence that MF59® adjuvanted seasonal influenza vaccines can reduce the chance of hospitalization due to influenza-related illness and potentially enhance protection for adults 65 years and older with weakened immune systems in a mismatched influenza season," said Gregg Sylvester, MD, Vice President of Medical Affairs at Seqirus. "At Seqirus, we remain on the front line of influenza prevention, committed to partnering with key industry stakeholders to advance new research and technological innovation in influenza vaccine development to help protect vulnerable populations."

In the U.S., influenza impacts adults 65 years and older with higher hospitalization and death rates compared to young, healthy adults.5 Influenza vaccine effectiveness also tends to be lower in this population due to age-related immune decline, which reduces the body's ability to produce a sufficient, protective immune response to the vaccine.6

FLUAD utilizes MF59 adjuvant technology, designed to create a strong, broad and durable immune response.7,8,9,10 FLUAD has an extensive clinical legacy, with 114+ million doses distributed and licensure in 29 countries since it was first approved in 1997.11,12

About the Study1
Researchers conducted an observational cluster-randomized trial where 50,012 nursing home residents at 823 Medicare-certified nursing homes received one of two influenza vaccines— adjuvanted trivalent influenza vaccine (aTIV) or standard trivalent influenza vaccine (TIV)— during the 2016/17 influenza season to evaluate the potential role of aTIV in improving clinical outcomes, with a primary endpoint of all-cause hospitalization rate. A portion of residents (15%) elected not to accept either vaccine. Intent-to-treat analysis with adjustments made for variables between the two sets of residents indicated a significant reduction of 6 percent in all-cause hospitalization was observed among adults 65 years and older who received FLUAD compared with those who received standard egg-based TIV (adjusted hazard ratio 0.94, 95% CI: 0.89,0.99, p=0.02). Further, hospitalization rates for influenza and pneumonia indicated a significant reduction of 20 percent among those who received FLUAD compared with those who received standard egg-based TIV (adjusted hazard ratio 0.80, 95% CI: 0.66, 0.98, p=0.03). There were no significant differences in respiratory-related hospitalizations or mortality between the study groups. 

A potential limitation of this study is that it was conducted during a severe A/H3N2 influenza season in a year where vaccines were less effective and egg-based vaccines were subject to egg-adaptation.2,3 

About Seasonal Influenza 
Influenza is a common, highly contagious infectious disease that can cause severe illness and life-threatening complications in many people.13 To reduce the risk of more serious outcomes, such as hospitalization and death, resulting from influenza, the CDC recommends annual vaccination for all individuals aged 6 months and older.14 Because transmission of influenza viruses to others may occur one day before symptoms develop and up to 5 to 7 days after becoming sick, the disease can be easily transmitted to others.13 Influenza can lead to clinical symptoms varying from mild to moderate respiratory illness to severe complications, hospitalization and in some cases, death.13 Preliminary estimates from the CDC report that up to 647,000 people in the United States were hospitalized due to influenza-related complications during the 2018/19 influenza season.15 Since it takes about two weeks after vaccination for antibodies to develop in the body that protect against influenza virus infection, it is recommended that people get vaccinated to help protect them before influenza begins spreading in their community.14

About Seqirus
Seqirus is part of CSL Limited (ASX:CSL), headquartered in Melbourne, Australia. The CSL Group of companies employs more than 22,000 people with operations in more than 60 countries.
Seqirus was established on 31 July 2015 following CSL's acquisition of the Novartis influenza vaccines business and its subsequent integration with bioCSL. As one of the largest influenza vaccine providers in the world, Seqirus is a major contributor to the prevention of influenza globally and a transcontinental partner in pandemic preparedness. Seqirus operates state-of-the-art production facilities in the U.S., the UK and Australia, and manufactures influenza vaccines using both egg-based and cell-based technologies. It has leading R&D capabilities, a broad portfolio of differentiated products and a commercial presence in more than 20 countries.

About CSL
CSL (ASX:CSL) is a leading global biotechnology company with a dynamic portfolio of life-saving medicines, including those that treat haemophilia and immune deficiencies, as well as vaccines to prevent influenza. Since our start in 1916, we have been driven by our promise to save lives using the latest technologies. Today, CSL — including our two businesses, CSL Behring and Seqirus - provides life-saving products to more than 60 countries and employs more than 22,000 people. Our unique combination of commercial strength, R&D focus and operational excellence enables us to identify, develop and deliver innovations so our patients can live life to the fullest. For more information about CSL Limited, visit

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Intended Audience
This press release is issued from Seqirus USA Inc. in Summit New Jersey, USA and is intended to provide information about our global business. Please be aware that information relating to the approval status and labels of approved Seqirus products may vary from country to country. Please consult your local regulatory authority on the approval status of Seqirus products.

Forward-Looking Statements
This press release may contain forward-looking statements, including statements regarding future results, performance or achievements. These statements involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. These statements reflect our current views with respect to future events and are based on assumptions and subject to risks and uncertainties. Given these uncertainties, you should not place undue reliance on these forward-looking statements.


FLUAD® (Influenza Vaccine, Adjuvanted) is an inactivated influenza vaccine indicated for active immunization against influenza disease caused by influenza virus subtypes A and type B contained in the vaccine. FLUAD is approved for use in persons 65 years of age and older.

Severe allergic reaction to any component of the vaccine, including egg protein, or after a previous dose of any influenza vaccine. 


  • If Guillain-Barré syndrome (GBS) has occurred within six weeks of previous influenza vaccination, the decision to give FLUAD should be based on careful consideration of the potential benefits and risks. 


  • The most common (≥10%) local (injection site) adverse reactions observed in clinical studies were injection site pain (25%) and tenderness (21%).
  • The most common (≥10%) systemic adverse reactions observed in clinical studies were myalgia (15%), headache (13%), and fatigue (13%). 

To report SUSPECTED ADVERSE REACTIONS, contact Seqirus at 1- 855-358-8966 or VAERS at 1-800-822-7967 and

For more information, please see accompanying US full Prescribing Information for FLUAD.

FLUAD® is a trademark of Seqirus UK Limited or its affiliates. 

MF59® is a trademark of Novartis AG, Basel, Switzerland.


Polina Miklush 
+1 (908) 608-7170

1 Gravenstein S, Davidson HE, Mcconeghy K, et al. (2019). Effectiveness of Adjuvanted vs. Non-Adjuvanted Influenza Vaccine in U.S. Nursing Homes. Presented at NFID 2019 Clinical Vaccinology Course, November 2019.

2 Centers for Disease Control and Prevention (CDC).  Accessed November 2019.

3 Wu N, Zost SJ, Thompson AJ et al. A structural explanation for the low effectiveness of the seasonal influenza H3N2 vaccine. PLOS Pathogens 2017;13:e1006682. 

4 Flannery B, Chung JR, Monto AS, et al. Influenza vaccine effectiveness in the United States during the 2016-2017 season. Clin Infect Dis. 2019;68(11):1798–1806. doi:10.1093/cid/ciy775

5 CDC. (2018). People 65 years and older & influenza. Retrieved from: Accessed November 2019.

6 Monto AS, Ansaldi F, Aspinall R, et al. (2009). Influenza control in the 21st century: Optimizing protection of older adults. Vaccine. 2009;27:5043-5053.

7 FLUAD® TRIVALENT (Influenza Vaccine, Adjuvanted) [package insert]. Holly Springs, NC: Seqirus Inc; 2018.

8 Frey SE, Aplasca-De Los Reyes MR, Reynales H, et al. (2014). Comparison of the safety and immunogenicity of an MF59®-adjuvanted with a non-adjuvanted seasonal influenza vaccine in elderly subjects. Vaccine. 2014;32:5027-5034.

9 O'Hagan DT, Ott GS, Nest GV, Rappuoli R, Giudice GD. (2013). The history of MF59® adjuvant: a phoenix that arose from the ashes. Expert Rev Vaccines. 2013;12(1):13-3.

10 Banzhoff A, Pellegrini M, Del Giudice G, Fragapane E, Groth N, Podda A. (2008). MF59-adjuvanted vaccines for seasonal and pandemic influenza prophylaxis. Influenza Other Respir Viruses. 2008;2(6):243-249.

11 Data on file. Seqirus Inc; 2019.

12 Data on file. Seqirus Inc; 2019.

13 CDC. (2018). Key facts about influenza (flu). Retrieved from: Accessed November 2019.

14 CDC. (2018). Key facts about seasonal flu vaccine. Retrieved from: Accessed November 2019.

15 CDC. (2019). 2018-2019 U.S. Flu season: Preliminary burden estimates. Retrieved from: Accessed November 2019.

This study was supported by a grant from Seqirus. 


SOURCE Seqirus

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