Seqirus UK Ltd.

A real-world evidence (RWE) study recently published in Open Forum Infectious Diseases (OFID) examined three consecutive U.S. flu seasons in the United States. The study suggests that cell-based quadrivalent influenza vaccine (QIVc) may have the potential to be more effective than egg-based vaccines (QIVe) in preventing test-confirmed influenza.1 The study results reveal that the relative vaccine effectiveness of QIVc versus QIVe in prevention of test-confirmed influenza was at least 10% higher across three consecutive flu seasons, 2017–2020.1 SUMMIT, N.J., May 2, 2024 /PRNewswire/ -- CSL Seqirus, a business of CSL (ASX: CSL), today announced a real-world evidence (RWE) study recently published in Open Forum Infectious Diseases (OFID), showing that a cell-based quadrivalent influenza vaccine (QIVc) prevented more test-confirmed influenza cases among individuals 4–64 years of age compared with the egg-based quadrivalent influenza vaccine (QIVe) over three consecutive U.S. influenza seasons (2017–2020).1 These data add to the growing wealth of evidence supporting the benefits of cell-based influenza vaccines. The study collected RWE from 31,824, 33,388, and 34,398 subjects in the 2017–2018, 2018–2019, and 2019–2020 seasons, respectively.1 Findings show a higher relative effectiveness of QIVc over QIVe in the prevention of test-confirmed influenza, with estimated relative vaccine effectiveness (rVE) of 14.8% for the 2017–18 season, 12.5% for 2018–19, and 10.0% for 2019–20.1 rVE means the effectiveness of one vaccine relative to another. "This study exemplifies the value of RWE in generating valuable insights into the effectiveness of influenza vaccines," said Alicia N. Stein, Director, Real World Evidence, Center for Outcomes Research and Epidemiology, CSL Seqirus. "With data collected over three consecutive seasons, our study suggests higher vaccine effectiveness of cell-based quadrivalent influenza vaccines compared with standard egg-based influenza vaccines." Influenza vaccines produced using egg-based manufacturing can undergo adaptation within the manufacturing process, which may result in a mismatch between the strains covered in the vaccine and those that are identified by the World Health Organization (WHO).2 "Cell-based technology allows us to provide an exact antigenic match to the WHO's identified strains, helping to improve vaccine effectiveness versus standard egg-based vaccines. These data build on the growing evidence of real-world data that shows the benefits of our cell-based influenza vaccine," said Gregg Sylvester, Chief Health Officer and Head of Medical Affairs, CSL Seqirus. "At CSL Seqirus, we're continually driving vaccine technology forward, in order to improve effectiveness and help keep communities healthy." About the Study Researchers used a retrospective test-negative design (TnD) to estimate the relative vaccine effectiveness (rVE) of QIVc versus QIVe among individuals aged 4–64 years who had an acute respiratory or febrile illness and were tested for influenza in routine outpatient care.1 The study, the largest TnD RWE for QIVc to date, included 31,824, 33,388, and 34,398 subjects in the 2017–2018, 2018–2019, and 2019–2020 seasons, respectively; ~10% received QIVc and ~90% received QIVe.1 The results reveal higher relative vaccine effectiveness of QIVc versus QIVe in prevention of test-confirmed influenza; rVEs were 14.8% in 2017–2018, 12.5% in 2018–2019, and 10.0% in 2019–2020.1 Study Limitations The above study featuring RWE was subject to the typical limitations associated with retrospective cohort analyses. Observational studies have limitations including the potential for selection bias and residual confounding. TnD studies offer significant advantages over other observational studies and reflect the real world, however they are not as definitive as Randomized Controlled Trials (RCTs) in establishing causality. We recommend interpreting these results within a comprehensive evidence framework that includes various study designs for a well-rounded perspective on vaccine efficacy/effectiveness. About Seasonal Influenza Influenza is a frequently occurring, contagious seasonal respiratory disease that may cause severe illness and life-threatening complications in some people.3 Influenza can lead to clinical symptoms varying from mild to moderate respiratory illness to severe complications, hospitalization and in some cases, death.3 Because transmission of influenza viruses to others may occur before symptoms develop and up to 5 to 7 days after becoming sick, the disease can be easily transmitted to others.3 Preliminary estimates from the Centers for Disease Control and Prevention (CDC) report that during the 2023/24 influenza season, there have been an estimated 380,000-780,000 influenza-related hospitalizations in the U.S.4 The CDC recommends annual vaccination for individuals aged 6 months and older, who do not have any contraindications.5 Since it takes about two weeks after vaccination for antibodies to develop in the body that help protect against influenza virus infection, it is recommended that people get vaccinated before influenza begins spreading in their community.5 The CDC recommends that most people get vaccinated by the end of October.5 About CSL Seqirus CSL Seqirus is part of CSL (ASX: CSL). As one of the largest influenza vaccine providers in the world, CSL Seqirus is a major contributor to the prevention of influenza globally and a transcontinental partner in pandemic preparedness. With state-of-the-art production facilities in the U.S., the U.K. and Australia, and leading R&D capabilities, CSL Seqirus utilizes egg, cell and adjuvant technologies to offer a broad portfolio of differentiated influenza vaccines in more than 20 countries around the world. For more information about CSL Seqirus, visit CSL.com. About CSL CSL (ASX: CSL) (USOTC: CSLLY) is a global biotechnology company with a dynamic portfolio of medicines, including those that treat hemophilia and immune deficiencies, vaccines to prevent influenza, and therapies in iron deficiency and nephrology. Since our start in 1916, we have been driven by our promise to save lives using the latest technologies. Today, CSL – including our three businesses: CSL Behring, CSL Seqirus and CSL Vifor – provides products to patients in more than 100 countries and employs 32,000 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 inspiring stories about the promise of biotechnology, visit CSL.com/we-are-csl/vita-original-stories and follow us on Twitter.com/CSL. For more information about CSL, visit . Intended Audience This press release is issued from CSL Seqirus 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 CSL Seqirus products may vary from country to country. Please consult your local regulatory authority on the approval status of CSL 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. FLUCELVAX® QUADRIVALENT (Influenza Vaccine ) IMPORTANT SAFETY INFORMATION What is FLUCELVAX® QUADRIVALENT (Influenza Vaccine)? FLUCELVAX QUADRIVALENT is a vaccine that helps protect people aged 6 months and older from the flu. Vaccination with FLUCELVAX QUADRIVALENT may not protect all people who receive the vaccine. Who should not get FLUCELVAX QUADRIVALENT? You should not get FLUCELVAX QUADRIVALENT if you have had a severe allergic reaction to any of the ingredients in the vaccine. Before receiving FLUCELVAX QUADRIVALENT, tell your healthcare provider about all medical conditions, including if you: have ever had Guillain-Barré syndrome (severe muscle weakness) within six weeks after getting a flu vaccine. The decision to give FLUCELVAX QUADRIVALENT should be made by your healthcare provider, based on careful consideration of the potential benefits and risks. have problems with your immune system or are taking certain medications that suppress your immune system, as these may reduce your immune response to the vaccine have ever fainted when receiving a vaccine What are the most common side effects of FLUCELVAX QUADRIVALENT? pain, redness, swelling, and/or a raised hardened area where the vaccine was given headache overtiredness with low energy muscle aches feeling unwell (malaise) Additional side effects seen in children include: tenderness or bruising where vaccine was given sleepiness irritability diarrhea changes in eating habits These are not all of the possible side effects of FLUCELVAX QUADRIVALENT. You can ask your healthcare provider for more information and for advice about any side effects that concern you. To report SUSPECTED ADVERSE REACTIONS, contact CSL Seqirus at 1‑855‑358-8966 or VAERS at 1‐800‐822‐7967 or . You are also encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1‐800‐FDA‐1088. Before receiving this vaccine, please see the full US Prescribing Information for FLUCELVAX QUADRIVALENT. The information provided here does not include all that is known about FLUCELVAX QUADRIVALENT. To learn more, talk with your healthcare provider or pharmacist. FLUCELVAX® QUADRIVALENT is a registered trademark of Seqirus UK Limited or its affiliates. MEDIA CONTACT Tiffany Cody +1 (908) 370-1863 [email protected] USA-CRP-24-0014 1 Stein, Alicia N et al. "Relative vaccine effectiveness of cell-based versus egg-based quadrivalent influenza vaccine against test-confirmed influenza over three seasons between 2017 and 2020." Open Forum Infectious Diseases 2024. DOI: . 2 Peck, Heidi et al. "Enhanced isolation of influenza viruses in qualified cells improves the probability of well-matched vaccines." NPJ vaccines vol. 6,1 149. 9 Dec. 2021, DOI: 10.1038/s41541-021-00415-3. 3 Centers for Disease Control and Prevention (CDC). (2024). Key Facts about Influenza. Retrieved from . Accessed May 2024. 4 CDC. (2024). 2023-2024 U.S. Flu Season: Preliminary In-Season Burden Estimates. Retrieved from: . Accessed May 2024. 5 CDC. (2024). Who Needs a Flu Vaccine and When. Retrieved from: . Accessed May 2024. SOURCE CSL Seqirus

Data evaluating the impact of cell-based quadrivalent influenza vaccines suggests an additional 31%–39% of influenza cases may have been prevented among persons 0–64 years of age during the 2017-2020 U.S. flu seasons.1 Vaccination of children 6 months to 17 years of age with cell-based quadrivalent influenza vaccines would be cost-effective in >95% of simulations, compared to traditional egg-based vaccines based on modeling data from 2011/12 and 2017/18 U.S. flu seasons.2 Influenza vaccination with an adjuvanted quadrivalent influenza vaccine or standard-dose egg-based quadrivalent vaccine significantly reduced cardiovascular, respiratory, and other complications of influenza among U.S. adults 65 years of age and older over the 2018/19 and 2019/20 influenza seasons.3 SUMMIT, N.J., Oct. 11, 2023 /PRNewswire/ -- CSL Seqirus, a business of CSL (ASX: CSL), today announced new data from three studies supporting the clinical, public health and economic value of both cell-based and adjuvanted seasonal influenza vaccines. The data highlights the effectiveness and value of influenza vaccination in the U.S. across all relevant age groups, risk pro and influenza seasons with different levels of influenza burden.1,2,3 These analyses will be presented during poster sessions this week at the IDWeek 2023 conference taking place in Boston, Mass. from October 11-15, 2023. Modeling data showed a cell-based quadrivalent (IIV4c) vaccine provided substantial public health benefit compared with an egg-based quadrivalent inactivated influenza vaccine (IIV4).1 It is estimated that use of IIV4c in U.S. people 0-64 years of age would have prevented nearly an additional 6.4 million illnesses, alongside an additional reduction of over 3.1 million outpatient visits, 40,000 hospitalizations, and 8,000 ICU admissions and deaths during the 2017-2020 flu seasons.1 In addition, modeling data comparing economic and health impacts of vaccination with a cell-based quadrivalent influenza vaccine (QIVc) to the standard-dose egg-based quadrivalent vaccine (QIVe) in U.S. children 6 months to 17 years of age showed that vaccination with QIVc in both low- and high-incidence flu seasons would be a cost-saving strategy.2 Predictive data suggests the societal cost impact of flu may be reduced by over $1.4 billion depending on the rate of incidence in a flu season.2 "By analyzing healthcare and economic data, we can contribute to our understanding of improved vaccine effectiveness of specific influenza vaccines at the population level," said Mendel Haag, Senior Director, Center of Outcomes Research & Epidemiology, CSL Seqirus. "Observing an ever-growing set of real-world outcomes is critical to ensuring that cell-based influenza vaccine technology continues to push public health forward." A third study examined the impact of vaccination of older U.S. adults with an adjuvanted quadrivalent influenza vaccine or standard-dose egg-based quadrivalent vaccine.3 Results showed a significant reduction in cardiovascular, respiratory, and other complications of influenza among vaccinated U.S. adults 65 years of age and older during recent flu seasons.3 "These studies strengthen the evidence base supporting the effectiveness of our cell-based and adjuvanted influenza vaccines in mitigating the consequences of influenza for health and healthcare systems," said Joaquin Mould-Quevedo, Global Health Economic and Value Strategy Director, CSL Seqirus. "With the 2023/24 Northern Hemisphere influenza season underway, we're committed to working with our partners in public health to help demonstrate the importance of vaccination for our communities and health systems, particularly following a significant drop in flu immunization rates since the COVID-19 pandemic." About the Studies Presented at IDWeek 2023 Estimated additional burden averted from use of cell-based influenza vaccines compared to egg-based influenza vaccines among people 0–64 years of age in the United States: 2017–2020 seasons This study estimated the public health impact of vaccination with a cell-based quadrivalent inactivated influenza vaccine (IIV4c) compared with an egg-based inactivated quadrivalent influenza (IIV4) in all vaccinated people 0–64 years of age across the 2017/18 through 2019/20 influenza seasons in the U.S.1 For this purpose, a standard modeling method for estimating overall burden averted due to influenza vaccination (compared with no vaccination) as developed by the U.S. Centers for Disease Control and Prevention (CDC) was extended to a relative vaccine effectiveness (rVE) context.1 The study found that during the 2017/18 through 2019/20 influenza seasons, the use of IIV4c instead of IIV4 among U.S. persons aged 0–64 years would have had a substantial public health impact.1 Specifically, the use of IIV4c instead of IIV4 would have prevented almost an additional 6.4 million illnesses (a reduction of 31%–39%), alongside an additional reduction of 3.1 million outpatient visits, 40,000 hospitalizations, and thousands of ICU admissions and deaths across all three seasons combined.1 The value of the influenza cell-based vaccine in the pediatric population: A dynamic transmission modelling approach in the U.S. A second analysis of cell-based vaccines evaluated the economic and health impacts of the cell-based quadrivalent influenza vaccine (QIVc) compared with the standard-dose egg-based quadrivalent vaccine (QIVe) in U.S. children aged 6 months to 17 years.2 The analysis used a dynamic age-structured susceptible-exposed-infected-recovered transmission model calibrated to a low-incidence influenza season (2011/12) and high-incidence influenza season (2017/18).2 Results showed that the use of QIVc instead of QIVe in this population would be cost-saving from both a payer and societal perspective in the U.S.2 In both seasons, vaccination with QIVc demonstrated a potential ~$1.4 billion and $469 million savings from a societal perspective and ~$990 million and $253 million savings from a payer perspective, respectively.2 Sensitivity analysis demonstrated that QIVc would be cost-effective in >95% of simulations, with reductions of up to 65% in cases, hospitalizations, and influenza-related mortality.2 The value of influenza vaccination in the older adult population. A stochastic model estimation of the benefit of vaccination to prevent the severe outcomes in the U.S. Standard-dose egg-based quadrivalent vaccine (QIVe) or an adjuvanted quadrivalent influenza vaccine (aQIV) substantially reduced the estimated incidence of hospitalization and deaths due to influenza complications in this population and incremental differences between the two vaccines estimated further reductions in hospitalizations and deaths from aQIV vs QIVe of 1,071–18,388 and 85–1,944, respectively across the three evaluated outcomes (respiratory illness, cardiovascular disease, and other).3 During the last two recent pre-pandemic seasons (2018/19 and 2019/20), 44–54% of hospitalizations and 63–77% of deaths from influenza in the U.S. were in adults aged 65 years and older.4,5 These findings further highlighted the importance of influenza vaccination in reducing cardiovascular, respiratory and other complications of influenza in older adults, particularly those with underlying conditions, as well as lessening the burden on health systems. Study Limitations As with all simulations, analyses based on models have several limitations based on a model's parameters and available data, as well as annually varying vaccine effectiveness. Modeling may underestimate the true number of cases averted for several reasons. First, the static structure of the first study used does not account for the indirect benefits of vaccination, such as herd immunity and reduction of transmission due to reduction in cases. Additionally, CDC disease burden estimates correspond to the overall population (including both vaccinated and unvaccinated people), which may cause an underestimation of averted cases in the unvaccinated. Additionally, modeling may not capture potential variability between sub-groups where groupings such as age-specific data were not present. About Seasonal Influenza Influenza is a common, contagious seasonal respiratory disease that may cause severe illness and life-threatening complications in some people.6 Influenza can lead to clinical symptoms varying from mild to moderate respiratory illness to severe complications, hospitalization and in some cases, death.6 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.6 Preliminary estimates from the Centers for Disease Control and Prevention (CDC) report that during the 2022/23 influenza season, there were an estimated 300,000-650,000 influenza-related hospitalizations in the U.S.7 The CDC recommends annual vaccination for individuals aged 6 months and older, who do not have any contraindications.8 Since it takes about two weeks after vaccination for antibodies to develop in the body that help protect against influenza virus infection, it is recommended that people get vaccinated before influenza begins spreading in their community.8 The CDC recommends that for most people who need only 1 dose of flu vaccine, vaccination should ideally happen in September or October.8 About CSL Seqirus CSL Seqirus is part of CSL (ASX:CSL). As one of the largest influenza vaccine providers in the world, CSL Seqirus is a major contributor to the prevention of influenza globally and a transcontinental partner in pandemic preparedness. With state-of-the-art production facilities in the U.S., the U.K. and Australia, and leading R&D capabilities, CSL Seqirus utilizes egg, cell and adjuvant technologies to offer a broad portfolio of differentiated influenza vaccines in more than 20 countries around the world. For more information about CSL Seqirus, visit CSLSeqirus.com. About CSL CSL (ASX:CSL) (USOTC:CSLLY) is a global biotechnology company with a dynamic portfolio of lifesaving medicines, including those that treat haemophilia and immune deficiencies, vaccines to prevent influenza, and therapies in iron deficiency and nephrology. Since our start in 1916, we have been driven by our promise to save lives using the latest technologies. Today, CSL – including our three businesses: CSL Behring, CSL Seqirus and CSL Vifor – provides lifesaving products to patients in more than 100 countries and employs 32,000 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 inspiring stories about the promise of biotechnology, visit CSL.com/Vita and follow us on Twitter.com/CSL. For more information about CSL, visit . Intended Audience This press release is issued from CSL Seqirus 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 CSL Seqirus products may vary from country to country. Please consult your local regulatory authority on the approval status of CSL 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. USA-QIVc-23-0078 MEDIA CONTACT Tiffany Cody +1 (908) 370-1863 Tiffany.Cody@Seqirus.com FLUCELVAX® QUADRIVALENT (Influenza Vaccine) IMPORTANT SAFETY INFORMATION What is FLUCELVAX® QUADRIVALENT (Influenza Vaccine)? FLUCELVAX QUADRIVALENT is a vaccine that helps protect people aged 6 months and older from the flu. Vaccination with FLUCELVAX QUADRIVALENT may not protect all people who receive the vaccine. Who should not get FLUCELVAX QUADRIVALENT? You should not get FLUCELVAX QUADRIVALENT if you have had a severe allergic reaction to any of the ingredients in the vaccine. Before receiving FLUCELVAX QUADRIVALENT, tell your healthcare provider about all medical conditions, including if you: Have ever had Gullain-Barré syndrome (severe muscle weakness) within six weeks of getting a flu vaccine. The decision to give FLUCELVAX QUADRIVALENT should be made by your healthcare provider, based on careful consideration of the potential benefits and risks. Have problems with your immune system or are taking certain medications that suppress your immune system, as these may reduce your immune response to the vaccine. Have ever fainted when receiving a vaccine. What are the most common side effects of FLUCELVAX QUADRIVALENT? Pain, redness, swelling, and/or a raised hardened area where the vaccine was given Headache Overtiredness with low energy Muscle aches Feeling unwell (malaise) Additional side effects seen in children include: Tenderness or bruising where vaccine was given Sleepiness Irritability Diarrhea Changes in eating habits These are not all of the possible side effects of FLUCELVAX QUADRIVALENT. You can ask your healthcare provider for more information and for advice about any side effects that concern you. To report SUSPECTED ADVERSE REACTIONS, contact CSL Seqirus 1-855-358-8966 or VAERS at 1-800-822-7967 or . You are also encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088. Before receiving this vaccine, please see the full US Prescribing Information for FLUCELVAX QUADRIVALENT. The information provided here does not include all that is known about FLUCELVAX QUADRIVALENT. To learn more, talk with your healthcare provider or pharmacist. FLUCELVAX® QUADRIVALENT is a registered trademark of Seqirus UK Limited or its affiliates. REFERENCES 1 McGovern I et al. Estimated additional burden averted from use of cell-based influenza vaccines compared to egg-based influenza vaccines among people 0–64 years of age in the United States: 2017–2020 seasons. Presented at IDWeek 2023. 2 Mould-Quevedo J, Nguyen V. The value of the influenza cell-based vaccine in the pediatric population: A dynamic transmission modelling approach in the U.S. Presented at IDWeek 2023. 3 Pelton, S, Nguyen V, Mould-Quevedo J. The value of influenza vaccination in the older adult population. A stochastic model estimation of the benefit of vaccination to prevent the severe outcomes in the U.S. Presented at IDWeek 2023. 4 Centers for Disease Control and Prevention (CDC). Estimated Flu-Related Illnesses, Medical visits, Hospitalizations, and Deaths in the United States — 2018–2019 Flu Season. Retrieved from . Accessed September 2023. 5 CDC. Estimated Flu-Related Illnesses, Medical visits, Hospitalizations, and Deaths in the United States — 2019–2020 Flu Season. Retrieved from . Accessed September 2023. 6 CDC. (2022). Key Facts about Influenza. Retrieved from . Accessed September 2023. 7 CDC. (2023). 2022-2023 Preliminary In-Season Burden Estimate. Retrieved from: . Accessed September 2023. 8 CDC. (2023). Who Needs a Flu Vaccine and When. Retrieved from: . Accessed September 2023. View original content: SOURCE CSL Seqirus Company Codes: Australia:CSL, OTC-PINK:CSLLY, OTC-BB:CSLLY

CSL Seqirus is the only influenza vaccine manufacturer that offers differentiated vaccine options for individuals six months of age and older. Since the COVID-19 pandemic, there has been a significant drop in influenza immunization rates and high levels of influenza-related illness, underscoring that flu is an ongoing threat.1,2 The Centers for Disease Control and Prevention (CDC) recommends annual influenza vaccination for all eligible people aged six months and older, as a critical tool to help prevent flu and lessen the severity of influenza-related illness and potentially life-threatening associated complications.3 SUMMIT, N.J., July 17, 2023 /PRNewswire/ -- CSL Seqirus, a business of CSL (ASX:CSL), today announced it has begun to ship its portfolio of innovative cell-based, adjuvanted and egg-based influenza vaccines across the U.S. in preparation for the 2023/24 influenza season. The company is positioned to supply over 55 million doses of influenza vaccines to healthcare providers across the U.S. "Last season underscored the devastating impact flu can have, with over 300,000 flu-related hospitalizations and 19,000 flu-related deaths reported based on preliminary data through April 2023," said Dr. Gregg Sylvester, Chief Health Officer, CSL Seqirus.2 "This year in the Southern Hemisphere, we're already seeing high levels of influenza activity, especially in children, which has historically been a strong predictor of what's to come in the Northern Hemisphere.4,5 As we commence shipment to healthcare providers across the U.S., it's critical that we raise immunization rates this season to help protect as many people as possible from influenza and its potentially life-threatening complications." CSL Seqirus is the only manufacturer to offer differentiated influenza vaccine options approved for use in individuals six months of age and older. This year's 2023/24 U.S. influenza season portfolio includes: FLUCELVAX® QUADRIVALENT (Influenza Vaccine), the first and only cell-based quadrivalent influenza vaccine indicated for use in people six months and older.6 By avoiding egg adaptation, cell-based flu vaccines provide an exact antigenic match to the World Health Organization--selected influenza virus strains.7,8,9 There were two real world evidence (RWE) studies conducted by the Marshfield Clinic Research Institute during the 2022/23 Northern Hemisphere season, in which a large majority (84%) of vaccinated participants received FLUCELVAX QUADRIVALENT. Influenza vaccine effectiveness was found to be 54% effective at preventing medical care cases in children and adults six months to 64 years of age, and 71% effective at preventing symptomatic flu among children ages 1 to 17 years of age.10 Limitations of these studies include small sample sizes from a single geographic area and the potential for confounding and bias. FLUCELVAX QUADRIVALENT immunogenicity, efficacy and safety are supported by randomized clinical trials.6 FLUAD® QUADRIVALENT (Influenza Vaccine, Adjuvanted), the first and only adjuvanted quadrivalent seasonal influenza vaccine for adults 65 years and older, is preferentially recommended by the CDC's Advisory Committee on Immunization Practices (ACIP) over standard-dose influenza vaccines.11,12 FLUAD QUADRIVALENT contains an MF59® adjuvant that, when added to a flu vaccine, is designed to strengthen, broaden, and lengthen the immune response.11,13,14 This is important for adults 65 years and older whose immune systems may have a decreased capacity to respond to flu illness or vaccines. AFLURIA® QUADRIVALENT (Influenza Vaccine), an egg-based, quadrivalent influenza vaccine approved for use in eligible people six months of age and older.15 The CDC recommends annual influenza vaccination for all eligible individuals, ages six months and older, as a critical tool to prevent and lessen the severity of disease.3 Annual influenza vaccination is especially important for people at a higher risk of developing serious influenza-related complications, including older adults, pregnant people and children younger than 5 years old.3,16 According to the CDC, most people who need only one dose of influenza vaccine for the season, should receive their vaccine in September or October.3 For children six months through 8 years of age, who require two vaccine doses, the CDC recommends they receive the first dose as soon as the vaccine is available, as early as July and August.3 For children of any age who need only one dose of flu vaccine or pregnant people in their third trimester, vaccination as early as July and August can also be considered. 3 "It's unfortunate that in a year when we saw an early onset and significant increase in influenza cases from the previous year, especially in children, vaccination rates in the U.S. and globally were so low," said Dave Ross, Vice President, North America Commercial Operations, CSL Seqirus. "Influenza vaccination is critical in reducing flu-related hospitalizations and overall burden of disease.17 At CSL Seqirus, we're committed to working with our public health partners to do what we can to help drive vaccination rates at least back up to pre-pandemic levels." For additional information on influenza vaccine options for the upcoming flu season, visit flu360.com. About Seasonal Influenza Influenza is a common, contagious seasonal respiratory disease that may cause severe illness and life-threatening complications in some people.17 Influenza can lead to clinical symptoms varying from mild to moderate respiratory illness to severe complications, hospitalization and in some cases, death.17 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.17 Preliminary estimates from the Centers for Disease Control and Prevention (CDC) report that during the 2022/23 influenza season, there were an estimated 300,000-650,000 influenza-related hospitalizations in the U.S.2 The CDC recommends annual vaccination for individuals aged 6 months and older, who do not have any contraindications.3 Since it takes about two weeks after vaccination for antibodies to develop in the body that help protect against influenza virus infection, it is recommended that people get vaccinated before influenza begins spreading in their community.3 The CDC recommends that for most people who need only 1 dose of flu vaccine, vaccination should ideally happen in September or October.3 About CSL Seqirus CSL Seqirus is part of CSL (ASX:CSL). As one of the largest influenza vaccine providers in the world, CSL Seqirus is a major contributor to the prevention of influenza globally and a transcontinental partner in pandemic preparedness. With state-of-the-art production facilities in the U.S., the U.K. and Australia, and leading R&D capabilities, CSL Seqirus utilizes egg, cell and adjuvant technologies to offer a broad portfolio of differentiated influenza vaccines in more than 20 countries around the world. For more information about CSL Seqirus, visit CSLSeqirus.com. About CSL CSL (ASX:CSL) (USOTC:CSLLY) is a global biotechnology company with a dynamic portfolio of lifesaving medicines, including those that treat haemophilia and immune deficiencies, vaccines to prevent influenza, and therapies in iron deficiency and nephrology. Since our start in 1916, we have been driven by our promise to save lives using the latest technologies. Today, CSL – including our three businesses: CSL Behring, CSL Seqirus and CSL Vifor – provides lifesaving products to patients in more than 100 countries and employs 32,000 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 inspiring stories about the promise of biotechnology, visit CSLBehring.com/Vita and follow us on Twitter.com/CSL. For more information about CSL, visit . Intended Audience This press release is issued from CSL Seqirus 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 CSL Seqirus products may vary from country to country. Please consult your local regulatory authority on the approval status of CSL 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. USA-CRP-23-0005 MEDIA CONTACT Tiffany Cody +1 (908) 370-1863 [email protected] FLUAD® QUADRIVALENT (Influenza Vaccine, Adjuvanted), FLUCELVAX® QUADRIVALENT (Influenza Vaccine), and AFLURIA® QUADRIVALENT (Influenza Vaccine) INDICATION AND IMPORTANT SAFETY INFORMATION What are FLUAD® QUADRIVALENT (Influenza Vaccine, Adjuvanted), FLUCELVAX® QUADRIVALENT (Influenza Vaccine), and AFLURIA® QUADRIVALENT (Influenza Vaccine)? FLUAD QUADRIVALENT is a vaccine that helps protect people aged 65 years and older from the flu. FLUCELVAX QUADRIVALENT is a vaccine that helps protect people aged 6 months and older from the flu. AFLURIA QUADRIVALENT is a vaccine that helps protect people aged 6 months and older from the flu. Vaccination with any of these may not protect all people who receive the vaccine. Who should not get FLUAD QUADRIVALENT, FLUCELVAX QUADRIVALENT, or AFLURIA QUADRIVALENT? You should not get FLUAD QUADRIVALENT nor AFLURIA QUADRIVALENT if you 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. You should not get FLUCELVAX QUADRIVALENT if you have had a severe allergic reaction to any of the ingredients in the vaccine. Before receiving FLUAD QUADRIVALENT, FLUCELVAX QUADRIVALENT, or AFLURIA QUADRIVALENT, tell your healthcare provider about all medical conditions, including if you: have ever had Guillain-Barré syndrome (severe muscle weakness) within six weeks after getting a flu vaccine. The decision to give any flu vaccine should be made by your healthcare provider, based on careful consideration of the potential benefits and risks. have problems with your immune system or are taking certain medications that suppress your immune system, as these may reduce your immune response to the vaccine have ever fainted when receiving a vaccine What are common side effects possible with FLUAD QUADRIVALENT, FLUCELVAX QUADRIVALENT, and AFLURIA QUADRIVALENT? pain, tenderness, redness, itching, bruising, swelling, and/or a raised hardened area where the vaccine was given headache overtiredness with low energy muscle aches feeling unwell (malaise) Additional side effects in children include: sleepiness irritability diarrhea changes in eating habits These are not all the possible side effects of FLUAD QUADRIVALENT, FLUCELVAX QUADRIVALENT, and AFLURIA QUADRIVALENT. You can ask your healthcare provider for more information. What do I do if I have side effects? Ask your healthcare provider for advice about any side effects that concern you. To report SUSPECTED ADVERSE REACTIONS, contact CSL Seqirus at 1-855-358-8966 or VAERS at 1-800-822-7967 and . You are also encouraged to report negative side effects of prescription drugs to the FDA. Visit , or call 1–800–FDA–1088. Before receiving this vaccine, please see the full US Prescribing Information for FLUAD QUADRIVALENT, FLUCELVAX QUADRIVALENT, or AFLURIA QUADRIVALENT. The information provided here does not include all that is known about FLUAD QUADRIVALENT, FLUCELVAX QUADRIVALENT, or AFLURIA QUADRIVALENT. To learn more, talk with your healthcare provider. FLUAD® QUADRIVALENT, FLUCELVAX® QUADRIVALENT, and AFLURIA® QUADRIVALENT are registered trademarks of Seqirus UK Limited or its affiliates. MF59® is a registered trademark of Seqirus UK Limited or its affiliates. REFERENCES 1 Centers for Disease Control and Prevention (CDC). Weekly Flu Vaccination Dashboard. Retrieved from: , Accessed June 2023. 2 CDC. 2022-2023 Preliminary In-Season Burden Estimate. Retrieved from: . Accessed June 2023. 3 CDC. Who Needs a Flu Vaccine and When. Retrieved from: . Accessed June 2023. 4 Zhang, Y., Yakob, L., Bonsall, M.B. et al. Predicting seasonal influenza epidemics using cross-hemisphere influenza surveillance data and local internet query data. Sci Rep 9, 3262 (2019). . 5 Australian Government Department of Health and Aged Care. AISR fortnightly report No. 5 – 29 May to 11 June 2023. Retrieved from: . Accessed June 2023. 6 FLUCELVAX® QUADRIVALENT (Influenza Vaccine) [package insert]. Holly Springs, NC: CSL Seqirus Inc, 2023. 7 Rajaram S, Boikos C, Gelone DK, Gandhi A. Influenza vaccines: the potential benefits of cell-culture isolation and manufacturing. Ther Adv Vaccines Immunother. 2020;8:2515135520908121. doi: 10.1177/2515135520908121. 8 CDC. Cell-based flu vaccines. Retrieved from . Accessed June 2023. 9 Rockman S, Laurie K, Ong C, Rajaram S, McGovern I, Tran V, Youhanna J. Cell-Based Manufacturing Technology Increases Antigenic Match of Influenza Vaccine and Results in Improved Effectiveness. Vaccines. 2023; 11(1):52. . 10 McLean HQ, Petrie JG, Hanson KE, et al. Interim Estimates of 2022–23 Seasonal Influenza Vaccine Effectiveness — Wisconsin, October 2022–February 2023. MMWR Morb Mortal Wkly Rep 2023;72:201–205. 11 FLUAD® QUADRIVALENT (Influenza Vaccine, Adjuvanted) [package insert]. Holly Springs, NC: CSL Seqirus Inc, 2023. National 12 Grohskopf LA, Blanton LH, Ferdinands JM, et al. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices — United States, 2022–23 Influenza Season. MMWR Recomm Rep 2022;71(No. RR-1):1–28. . 13 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. 14 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. 15 AFLURIA® QUADRIVALENT [package insert]. Parkville, AU: CSL Seqirus Inc, 2023. 16 CDC. People at Higher Risk of Flu Complications. . Accessed June 2023. 17 CDC. Key Facts about Influenza. Retrieved from . Accessed June 2023. SOURCE CSL Seqirus