Synairgen Completes Recruitment of Hospitalised Patients in COVID-19 Trial

Southampton, UK – 28 May 2020: Synairgen plc (LSE: SNG), the respiratory drug discovery and development company, is pleased to announce that recruitment of 100 hospitalised patients in its clinical trial of SNG001 (inhaled formulation of interferon-beta-1a) in COVID-19 patients has now been completed.

The COVID-19 study

Synairgen’s clinical trial in COVID-19 patients (SG016) is a double-blind, placebo-controlled trial. The 220 patient trial comprises 100 patients initiated in hospital and 120 patients initiated in the home setting. The patients participating in the hospital setting have been recruited across a number of NHS trusts and the trial has been adopted by the NIHR Respiratory Translational Research Collaboration which is comprised of leading centres in respiratory medicine in the UK whose internationally recognised experts are working together to accelerate development and discovery for COVID-19. A successful outcome will inform onwards progression of SNG001 in COVID-19 patients. Results from the hospital setting are expected in July 2020, as announced in the Company’s Preliminary Results statement on 26 May 2020.

Richard Marsden, CEO of Synairgen, commented: “We are pleased to have now completed recruitment in this important study, with initial trial data expected in July 2020. A successful outcome from this trial could be a critical step towards strengthening the fight against the COVID-19 pandemic.”

For further enquiries, please contact:

Synairgen plc

Richard Marsden, Chief Executive Officer

John Ward, Finance Director

Tel: + 44 (0) 23 8051 2800

finnCap

Geoff Nash, Kate Bannatyne, Charlie Beeson (Corporate Finance)

Alice Lane, Manasa Patil (ECM)

Tel: + 44 (0) 20 7220 0500

Consilium Strategic Communications (Financial Media and Investor

Relations)

Mary-Jane Elliott, Sue Stuart, Olivia Manser

synairgen@consilium-comms.com

Tel: +44 (0) 20 3709 5700