A new study finds promise in a drug associated with significantly reduced hospitalizations among high-risk patients who received an injection in the early stages of COVID-19 infection.

Edward Mills, one of the authors, said peginterferon lambda stands out as a potential “one-and-done” treatment for older patients, noting current options includemulti-dose infusions of monoclonal antibodies or the medication Paxlovid, which requires three pills repeated twice a day, for five days.

“It's by a syringe, subcutaneously under the skin, the same way you might deliver insulin, for example,” said Mills, a professor in the Department of Health Research Methods, Evidence, and Impact at McMaster University in Hamilton.

“It could also be self-administered.”

The randomized clinical trial involved1,949 participants between June 2021 and March 2021.

Those who received peginterferon lambda within three days had an 89 per cent reduction in risk of hospitalization. Those who received it within seven days were half as likely to be admitted to hospital, Mills said.

The vast majority of participants, 84 per cent, were vaccinated. Most were enrolled in Brazil, with only 30 participantsfrom Toronto because COVID-19 had not yet taken hold in Canada during the recruitment phase, said Mills, adding he led all the evaluations for the trial.

Results of the study were published Wednesday in the New England Journal of Medicine.

He added it was shown to be effective for multiple variants of COVID-19, including the highly transmissible Omicron variant.

Participants were aged 50 and over or had a health condition such as diabetes, obesity, cancer or high blood pressure, putting them at higher risk of complications from COVID-19.

A future study involving McMaster University is expected to determine whether peginterferon lambda can protect against a variety of respiratory viruses including influenza and respiratory syncytial virus, or RSV, Mills said.

Dr. Jordan Feld, another author of the study, said interferons are produced by the body to fight off viral infections such as the flu as part of its “antiviral machinery.”

“The difference with interferon lambda, which is this particular interferon, is that it's much more focused in where it acts,” said Feld, interim director of the Toronto Centre for Liver Disease.

He said interferon lambda has been studied extensively for hepatitis B and C and is being developed for hepatitis D. However, it's not used for those infections because of the availability of oral treatment.

This report by The Canadian Press was first published Feb. 8, 2023.


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