Annual General Meeting Presentation

Southampton, UK – 29 June 2023: Synairgen plc (LSE: SNG), the respiratory company developing SNG001, an investigational formulation for inhalation containing the broad-spectrum antiviral protein interferon beta, announces that at its Annual General Meeting, taking place today at 10am BST at Numis, 45 Gresham Street, London EC2V 7BF, the leadership team will deliver a presentation to attendees. A copy of the slides is now available on the Company’s website at www.Synairgen.com.

For further enquiries, please contact:

finnCap (NOMAD and Joint Broker)

Geoff Nash, Charlie Beeson (Corporate Finance)

Alice Lane, Sunil de Silva (ECM)

Tel: + 44 (0) 20 7220 0500

Numis Securities Limited (Joint Broker)

Freddie Barnfield, Duncan Monteith, Euan Brown

Tel: + 44 (0) 20 7260 1000

Consilium Strategic Communications (Financial Media and Investor Relations)

Mary-Jane Elliott, Namrata Taak, Lucy Featherstone

cscsynairgen@consilium-comms.com

Tel: +44 (0) 20 3709 5700

MKC STRATEGIES, LLC (US Media Relations)

Mary Conway

MConway@MKCStrategies.com

Tel: +1 516-606-6545

Notes for Editors

About Synairgen

Synairgen is a UK-based respiratory company focused on drug discovery, development and commercialisation. The Company’s primary focus is developing SNG001 (inhaled interferon beta) for the treatment of severe viral lung infections as potentially the first host-targeted, broad-spectrum antiviral treatment delivered directly into the lungs. SNG001 has been granted Fast Track status from the US Food and Drug Administration (FDA). Founded by University of Southampton Professors Sir Stephen Holgate, Donna Davies and Ratko Djukanovic in 2003, Synairgen is quoted on AIM (LSE: SNG). For more information about Synairgen, please see www.synairgen.com.