Coronavirus: Inhaled form of common drug shows promise in patients

LONDON • A British drug company said on Monday that an inhaled form of a commonly used medicine could slash the odds of Covid-19 patients becoming severely ill, a sliver of good news in the race to find treatments that was met by scientists with equal measures of caution and cheer.

The drug, based on interferon beta, a protein naturally produced by the body to orchestrate its response to viruses, has become the focus of intensifying efforts in Britain, China and the United States to treat Covid-19 patients.

Scientists have found that the coronavirus attacks the body in part by blocking its natural interferon response, disarming cells that would otherwise be alerting neighbouring cells to activate their own genes and fortify themselves against the invading virus.

In theory, administering interferon to patients could invigo-rate their defences in the early stages of illness. But giving patients interferon without eliciting serious side effects has proved to be challenging.

The symptoms of a seasonal flu, for example, are largely produced by the mobilisation of the body's interferon response, scientists said.

British drug company Synairgen tried to circumvent that problem by developing an inhaled form of interferon that directly targets cells in the lungs, rather than an injection, which can produce more intense side effects.

A small, double-blind trial that Synairgen conducted on coronavirus patients in nine British hospitals showed promising initial results. The inhaled form of interferon beta reduces the odds of hospitalised patients becoming severely ill - and needing ventilation, for example - by 79 per cent, compared with patients who received a placebo.

Patients receiving the interferon beta drug were also twice as likely as patients who received a placebo to recover.

Breathlessness was also lower in patients receiving the drug.

But the significance of the findings was seriously limited by the small size of the trial.

It involved only 101 patients, Synairgen said, making it difficult to know for certain how beneficial the drug was or how it affected patients differently.

The study could not rule out that the drug was only margi-nally effective.

Scientists also noted that while injectable interferon has historically been used to treat hepatitis infections, the inhaled form of treatment was not yet licensed or widely available.

King's College London professor of virology Stuart Neil said there had been fears early in the pandemic that giving interferon to patients could worsen the over-aggressive immune response that was itself sickening some of them.

But more recent findings have indicated that infected patients mount a limited interferon response on their own.

"It is very exciting," Prof Neil said. "By basically inhaling the interferon into the site of infection, it looks like you are taking the edge off the virus."

NYTIMES