DUBLIN – Synairgen plc has detected what appear to be promising efficacy signals in a phase II trial of its inhaled formulation of interferon beta 1a, SNG001, in COVID-19.

Those in the drug treatment group on the placebo-controlled study, which recruited 101 hospitalized patients, had 79% lower odds of developing severe disease, defined as requiring ventilation or death during the treatment period (day 1 – day 16), than those in the control arm. The results were statistically significant (odds ratio 0.21 [95% confidence interval (CI) 0.04–0.97]; p=0.046).

The company is not yet reporting on the primary endpoint, the change in condition measured on the ordinal scale of clinical improvement - the scale ranges from 0 (the patient is well) to a maximum of 8 (death) – out to day 28, but the company and its clinical collaborators said during a media briefing that this endpoint was also achieved with statistical significance.

The rate of recovery – defined as no limitation of activities or no clinical or virological evidence of infection during the treatment period – of those on SNG001 was twice that of those on placebo. That result was also statistically significant (hazard ratio 2.19 [95% CI 1.03–4.69]; p=0.043. In addition, the level of breathlessness experienced by those on drug was, the Southampton, U.K.-based company said “markedly reduced” over the treatment period as compared with those on placebo (p=0.007).

The study was not powered to demonstrate a survival benefit, but the trend was in SNG001’s favor: there were no deaths in the drug treatment group, whereas three patients (6%) in the control group died.

In patients with severe disease at the time of admission – defined as requiring supplemental oxygen – SNG001 increased the likelihood of hospital discharge during the study period, but the result was not statistically significant.

In comments distributed by the U.K.’s Science Media Center, Steve Goodacre, professor of emergency medicine at the University of Sheffield, took a critical view: “These results are not interpretable,” he stated. “We need the full details and, perhaps more importantly, the trial protocol. The trial should have been registered and a protocol made available before any analysis was undertaken. They could easily have included a link to the trial protocol in their press release. I am concerned they have not done this.”

According to the record for the trial held at CinicalTrials.gov (NCT04385095), secondary endpoints include:

  • progression to pneumonia;
  • time to clinical improvement;
  • change in the National Early Warning Score 2 (News 2), an assessment of acute illness severity that ranges from 0 (the patient is well) to 24 (the patient requires emergency intervention);
  • change in breathlessness;
    and several different safety and tolerability assessments.

Naveed Sattar, professor of metabolic medicine at the University of Glasgow, had a more positive reaction to the reported data: “The results seem very impressive, and although accepted that the trial is small with just over 100 participants, a 79% reduction in disease severity could be a game changer, he stated. “It would be good to see the full results once presented and peer-reviewed to make sure they are robust and the trial conduct was rigorous.”

Synairgen’s stock (LONDON:SNG) rocketed during early trading Monday (July 20), hitting £2.38 (US$3.01), a 552% increase on Friday’s close of 36.5 pence.