Chikungunya Fever

COPENHAGEN, Denmark, May 2, 2025 – Bavarian Nordic A/S (OMX: BAVA) announced today that the UK Medicines and Healthcare products Regulatory Agency (MHRA) has granted marketing authorization in the United Kingdom (UK) for VIMKUNYA® (recombinant, adsorbed) for active immunization for the prevention of disease caused by chikungunya virus in individuals 12 years and older. The vaccine was approved following MHRA review under the international recognition procedure, which is a targeted assessment that recognizes approvals from certain other regulatory bodies, in this case the recent approval by the European Commission. Bavarian Nordic is targeting launch of the vaccine in the UK during the summer of 2025. “Chikungunya mostly represents a risk for UK citizens traveling overseas to affected regions in the Americas, Africa and Asia, but as recent research has shown, invasive mosquitos known to carry the disease have established themselves in many parts of Southern Europe and are moving further north due to climate change1,” said Paul Chaplin, President and CEO of Bavarian Nordic. “The mosquitos cannot be stopped, but with preventative measures such as vaccines, we can mitigate the impact of emerging diseases like chikungunya for those at risk, and we look forward to launching our vaccine in the UK later this year.” The UK approval of VIMKUNYA marks the third approval of Bavarian Nordic’s chikungunya vaccine, which was approved by the U.S. Food and Drug Administration (FDA) and the European Commission in February 2025.2,3 Bavarian Nordic has also submitted an application to Health Canada, potentially supporting approval of the chikungunya vaccine in the first half of 2026. About chikungunyaChikungunya is a mosquito-borne disease caused by the chikungunya virus (CHIKV). In the past 20 years, the virus has emerged across several regions in Asia, Africa, and the Americas, including many popular travel destinations, often causing large unpredictable outbreaks. Since its discovery, CHIKV has been identified in more than 110 countries, with evidence of transmission confirmed in more than 50 countries over the past five years4. Chikungunya typically presents with acute symptoms, including fever, rash, fatigue, headache, and often severe and incapacitating joint pain. Most patients recover within 1-2 weeks, but 30-40% of those affected may develop chronic arthritis that can last for months or even years5. In 2024, 620,000 cases of chikungunya and over 200 deaths were reported worldwide6. Recent data suggest that chikungunya is severely underreported and often misdiagnosed as dengue fever due to a similar symptom profile7. About VIMKUNYA® Chikungunya vaccine (recombinant, adsorbed)VIMKUNYA is a single dose, prefilled, adjuvanted VLP recombinant protein vaccine for active immunization for the prevention of disease caused by chikungunya virus (CHIKV) in individuals 12 years and older. The US, EU and UK approvals of VIMKUNYA (CHIKV VLP vaccine) were all based on results from two phase 3 clinical trials which enrolled more than 3,500 healthy individuals 12 years of age and older. The studies met their primary endpoints, with results showing that 21 days after vaccination, the vaccine induced neutralizing antibodies in up to 97.8% of the vaccinated individuals, (97.8% in individuals 12 years to 64 and 87.3% in over 65 year olds). The key secondary endpoint of seroresponse rate at day 8 post vaccination was 46.6% and 96.8% at day 15 in the 12-64 year old population and 82.3% at day 15 for the over 65 population. The vaccine was well-tolerated and vaccine-related adverse events were mainly mild or moderate in nature. The most common side effects were pain at the injection site, fatigue, headache, and muscle pain. About Bavarian NordicBavarian Nordic is a global vaccine company with a mission to improve health and save lives through innovative vaccines. We are a preferred supplier of mpox and smallpox vaccines to governments to enhance public health preparedness and have a leading portfolio of travel vaccines. For more information, visit www.bavarian-nordic.com. Forward-looking statements This announcement includes forward-looking statements that involve risks, uncertainties and other factors, many of which are outside of our control, that could cause actual results to differ materially from the results discussed in the forward-looking statements. Forward-looking statements include statements concerning our plans, objectives, goals, future events, performance and/or other information that is not historical information. All such forward-looking statements are expressly qualified by these cautionary statements and any other cautionary statements which may accompany the forward-looking statements. We undertake no obligation to publicly update or revise forward-looking statements to reflect subsequent events or circumstances after the date made, except as required by law. Contact investors:Europe: Rolf Sass Sørensen, Vice President Investor Relations, rss@bavarian-nordic.com, Tel: +45 61 77 47 43US: Graham Morrell, Paddock Circle Advisors, graham@paddockcircle.com, Tel: +1 781 686 9600 Contact media:Nicole Seroff, Vice President Corporate Communications, nise@bavarian-nordic.com, Tel: +45 53 88 06 03 1 European Centre for Disease Prevention and Control. Increasing risk of mosquito-borne diseases in EU/EEA following spread of Aedes species. https://www.ecdc.europa.eu/en/news-events/increasing-risk-mosquito-borne-diseases-eueea-following-spread-aedes-species 2 Bavarian Nordic Receives U.S. FDA Approval of Chikungunya Vaccine for Persons Aged 12 and Older. https://www.bavarian-nordic.com/media/media/news.aspx?news=7053 3 Bavarian Nordic Receives Marketing Authorization in Europe for Chikungunya Vaccine for Persons Aged 12 and Older. https://www.bavarian-nordic.com/media/media/news.aspx?news=7056 4 Centers for Disease Control and Prevention. Areas at Risk for Chikungunya. https://www.cdc.gov/chikungunya/data-maps/index.html. 5 European Centre for Disease Prevention and Control. Chikungunya virus disease. https://www.ecdc.europa.eu/en/chikungunya-virus-disease. 6 European Centre for Disease Prevention and Control. Chikungunya virus disease case notification rate per 100 000 population, January 2024-December 2024. https://www.ecdc.europa.eu/en/publications-data/chikungunya-virus-disease-case-notification-rate-100-000-population-january-2024. 7 Ribas Freitas AR, Pinheiro Chagas AA, Siqueira AM, Pamplona de Góes Cavalcanti L. How much of the current serious arbovirus epidemic in Brazil is dengue and how much is chikungunya? Lancet Reg Health Am. 2024 Apr 30;34:100753. doi: 10.1016/j.lana.2024.100753. PMID: 38711542; PMCID: PMC11070701. Attachment 2025-05-02-en

Bavarian Nordic’s chikungunya vaccine application has been submitted for approval to Health Canada. Credit: Sonia Bonet/Shutterstock. The UK Medicines and Healthcare products Regulatory Agency (MHRA) has granted marketing authorisation to Bavarian Nordic’s Vimkunya (recombinant, adsorbed) vaccine for preventing chikungunya virus infection in people aged 12 and above. Vimkunya also received approvals from the US Food and Drug Administration (FDA) and the European Commission (EC). The vaccine’s authorisation in the UK was facilitated by the international recognition procedure, acknowledging the recent EC approval. Vimkunya’s launch in the country is anticipated by the summer of 2025. Bavarian Nordic’s chikungunya vaccine application has been submitted for approval to Health Canada, with potential authorisation expected in the first half of 2026. Designed as a prefilled, single-dose, adjuvanted virus-like particle recombinant protein vaccine, Vimkunya is approved for active immunisation to prevent the virus in these individuals. GlobalData Strategic Intelligence US Tariffs are shifting - will you react or anticipate? Don’t let policy changes catch you off guard. Stay proactive with real-time data and expert analysis. By GlobalData Learn more about Strategic Intelligence Approvals in the UK, EU and US were supported by the outcomes from two Phase III trials. These trials, which involved 3,500 healthy participants, met their primary endpoints, demonstrating the vaccine’s performance in inducing neutralising antibodies in up to 97.8% of the vaccinated subjects, within 21 days post-vaccination. Vimkunya was found to be tolerated well, with the most common side effects being injection site pain, headache, muscle pain and fatigue, mostly mild or moderate. Bavarian Nordic CEO and president Paul Chaplin stated: “Chikungunya mostly represents a risk for UK citizens travelling overseas to affected regions in the Americas, Africa and Asia, but as recent research has shown, invasive mosquitos known to carry the disease have established themselves in many parts of Southern Europe and are moving further north due to climate change.” In December 2024, the company entered a licence and manufacturing agreement with the Serum Institute of India for its mpox vaccine, MVA-BN.

France’s national public health agency is suspending immunization of adults 65 years and older with Valneva’s chikungunya vaccine Ixchiq after three patients were hospitalized, including one who died. The French authorities started a vaccination campaign earlier this year on the French islands of La Reunion and Mayotte in response to a chikungunya outbreak. All three people hospitalized in La Reunion were over 80 and had preexisting health conditions, Valneva said in a Saturday release . The company has delivered around 40,000 doses of Ixchiq to La Reunion as part of the campaign. Valneva’s shares were down around 8% on the Paris exchange at market open Monday. The change in guidance comes just two months after the CDC started an investigation of five people over 65 in the US who were taken to the hospital for cardiac or neurologic events after getting Ixchiq. Valneva’s chief medical officer Juan Carlos Jaramillo said in the release that the company is “working on a potential update of the product’s indication.” France’s health agency still recommends Ixchiq for people aged 18 to 64 living on the affected islands. The US says people planning to travel to countries with outbreaks should consider the vaccine. Ixchiq secured an FDA accelerated nod for adults in November 2023 and was launched in the US the year after. The vaccine reached €3.7 million in initial sales in 2024. But competition is looming after Bavarian Nordic’s chikungunya vaccine, called Vimkunya, received US approval for adults and adolescents in February. Valneva submitted a label expansion application with the FDA for Ixchiq to cover teens in November 2024. The chikungunya virus circulates in tropical and subtropical areas and is spread by mosquitoes. Symptoms of an infection include fever, rash, headaches, and joint and muscle pain.