Synairgen plc announces the first presentation of the full data analysis from its Phase 3 SPRINTER trial evaluating the efficacy and safety of SNG001 in patients hospitalised with COVID-19. SPRINTER (SG018; NCT04732949) was a global, randomised, placebo-controlled, double-blind clinical trial assessing the efficacy and safety of inhaled SNG001 for the treatment of adults hospitalised due to COVID-19 who required treatment with supplemental oxygen. The trial recruited a total of 623 patients who were randomised to receive SNG001 (n=309) or placebo (n=314) on top of standard of care (SOC).

The data from this pivotal trial will be presented at the Clinical Trials Symposium of the American Thoracic Society 2022 (ATS 2022) International Conference, being held in San Francisco, California from 13-18 May 2022. A separate poster presentation is scheduled for 17 May 2022. Synairgen announced in February 2022 that the Phase 3 SPRINTER trial did not meet the primary endpoints of discharge from hospital and recovery.

There was, however, an encouraging signal in reduction in the relative risk (RRR) of progression to severe disease or death within 35 days (25.7%1 reduction in the Intention-to-Treat population and 36.3% reduction in the Per Protocol population). To assess the strength of this signal and identify specific patient populations that might benefit most from treatment, post hoc analyses were performed on groups of patients recognised to be at greater risk of developing severe disease in hospital. These analyses included patients =65 years old, those with co-morbidities associated with worse COVID-19 outcomes, and those who, at baseline, despite receiving low flow oxygen, had clinical signs of compromised respiratory function (defined as oxygen saturation of = 92% or respiratory rate = 21 breaths/min).

These analyses showed stronger treatment effects with SNG001 in these high-risk patient sub-groups, with the strongest effect observed in those who had clinical signs of compromised respiratory function. In these patients, who represented approximately one-third of the SPRINTER trial population, SNG001 significantly reduced the risk of progression to severe disease and death compared to placebo by 70% in the Per Protocol population (Odds Ratio (95% Confidence Interval) 0.23 (0.06, 0.98); p=0.046). SNG001 was well tolerated in the SPRINTER trial with a favourable safety profile consistent with previous studies: The proportion of patients with any treatment-emergent adverse events (TEAE) related to study treatment was 22.6% for SNG001 vs.

25.4% for placebo. The proportion of patients with any serious TEAE was 12.6% for SNG001 vs. 18.2% for placebo.

The proportion of patients with a serious respiratory3 TEAE was 4.7% for SNG001 vs. 9.9% for placebo.