Synairgen announces positive results from trial of SNG001 in hospitalised COVID-19 patients

Synairgen plc, the respiratory drug discovery and development company which originated from research at the University of Southampton, is pleased to announce positive results from its clinical trial of SNG001, its wholly-owned inhaled formulation of interferon beta, in hospitalised COVID-19 patients.

Richard Marsden, CEO of Synairgen, said: "We are all delighted with the trial results announced today, which showed that SNG001 greatly reduced the number of hospitalised COVID-19 patients who progressed from ‘requiring oxygen’ to ‘requiring ventilation’. It also showed that patients who received SNG001 were at least twice as likely to recover to the point where their everyday activities were not compromised through having been infected by SARS-CoV-2. In addition, SNG001 has significantly reduced breathlessness, one of the main symptoms of severe COVID-19. This assessment of SNG001 in COVID-19 patients could signal a major breakthrough in the treatment of hospitalised COVID-19 patients. Our efforts are now focused on working with the regulators and other key groups to progress this potential COVID-19 treatment as rapidly as possible."

The double-blind placebo-controlled trial recruited 101 patients from 9 specialist hospital sites in the UK during the period 30 March to 27 May 2020. Patient groups were evenly matched in terms of average age (56.5 years for placebo and 57.8 years for SNG001), comorbidities and average duration of COVID-19 symptoms prior to enrolment (9.8 days for placebo and 9.6 days for SNG001).

Key findings:

• The odds of developing severe disease (e.g. requiring ventilation or resulting in death) during the treatment period (day 1 to day 16) were significantly reduced by 79% for patients receiving SNG001 compared to patients who received placebo (OR 0.21 [95% CI 0.04-0.97]; p=0.046).
• Patients who received SNG001 were more than twice as likely to recover (defined as ‘no limitation of activities’ or ‘no clinical or virological evidence of infection’) over the course of the treatment period compared to those receiving placebo (HR 2.19 [95% CI 1.03-4.69]; p=0.043).
• Over the treatment period, the measure of breathlessness was markedly reduced in patients who received SNG001 compared to those receiving placebo (p=0.007).
• Three subjects (6%) died after being randomised to placebo. There were no deaths among subjects treated with SNG001.
• In the patients with more severe disease at time of admission (i.e. requiring treatment with supplemental oxygen), SNG001 treatment increased the likelihood of hospital discharge during the study, although the difference was not statistically significant (HR 1.72 [95% CI 0.91-3.25]; p=0.096). Median time to discharge was 6 days for patients treated with SNG001 and 9 days for those receiving placebo. Furthermore, patients receiving SNG001 appeared to be more than twice as likely to have recovered by the end of the treatment period (HR 2.60 [95% CI 0.95-7.07]; p=0.062), although this strong trend did not reach statistical significance. However by day 28, patients receiving SNG001 treatment had statistically significantly better odds of recovery (OR 3.86 [95% CI 1.27-11.75]; p=0.017). Interestingly, the efficacy analyses indicate there is no evidence of an association between the SNG001 positive treatment effects and prior duration of COVID-19 symptoms.

Further analysis will be conducted over the coming weeks and reported in due course.

Professor Tom Wilkinson, Professor of Respiratory Medicine at the University of Southampton and Trial Chief Investigator, commented: "We are delighted with the positive data produced from this trial, which is the result of a momentous coordinated effort from Synairgen, the University of Southampton, University Hospital Southampton NHS Foundation Trust and the highly expert research teams across the NIHR network and regulatory bodies in the UK. The results confirm our belief that interferon beta, a widely known drug that, by injection, has been approved for use in a number of other indications, has huge potential as an inhaled drug to be able to restore the lung’s immune response, enhancing protection, accelerating recovery and countering the impact of SARS-CoV-2 virus.”

Professor Stephen Holgate CBE, Medical Research Council Clinical Professor of Immunopharmacology at the University of Southampton and Co-Founder of Synairgen, said: “Recognising that SARS-CoV-2 is known to have evolved to evade the initial antiviral response of the lung, our inhaled treatment of giving high local concentrations of interferon beta, a naturally occurring antiviral protein, restores the lung’s ability to neutralise the virus, or any mutation of the virus or co-infection with another respiratory virus such as influenza or RSV, as could be encountered in the winter if there is a resurgence of COVID-19.”