Single-dose treatment reduces risk of COVID-19 hospitalization by half for high-risk patients in a largely vaccinated population

Dr. Jordan Feld was one of the lead authors on the study that found the benefits of treatment were seen across different COVID-19 variants of concern, including the highly transmissible Omicron variant.

A single-dose of the antiviral drug peginterferon lambda reduced the risk of hospitalization or of a visit to the emergency department because of COVID-19 by half, according to a study published today in the New England Journal of Medicine.

The multi-centre phase 3 TOGETHER clinical trial – designed to test a new therapy in a real setting – evaluated the use of this drug in over 1,900 outpatients at high-risk of developing complications from COVID-19.

Patients who received a single-dose subcutaneous injection of peginterferon lambda within seven days of their first COVID-19 symptom had a 50 per cent lower risk of needing to be admitted to hospital when compared to people who received a placebo.

The trial was one of the first to test treatment in a largely vaccinated population. The research team found that a similar effect was seen in those who had received the vaccine (84 per cent) as in those who were unvaccinated.  The team also saw the benefits of treatment across multiple COVID-19 variants, including the highly transmissible Omicron variant.

“This much larger trial shows us that the antiviral benefits we previously observed translate to clinical benefit. The results conclusively show that this is an effective therapy to treat COVID-19 to reduce the risk of complications,” says one of the lead authors of the study Dr. Jordan Feld, Interim Director of the Toronto Centre for Liver Disease and Co-Director of the Schwartz Reisman Liver Research Centre and the R. Phelan Chair in Translational Liver Research at UHN.

“An important feature of this treatment is that it is not affected by changes or mutations in the virus, because it works by stimulating the body’s own response to viral infection,” added Dr. Feld, who is also a Senior Scientist at the Toronto General Hospital Research Institute at UHN and a Professor of Medicine at the University of Toronto.

Study participants reported few or no side effects, with no significant differences seen between the group that received the actual treatment and the group that received a matching placebo.

“This could be an important addition to our arsenal to fight COVID-19, especially for high-risk patients who may not be able to use currently available treatments because of side-effects or drug interactions with medications they take,” says Dr. Feld.

All participants were either 50 or older, or had a health condition that put them at higher risk for severe COVID-19, like diabetes, hypertension, obesity, or being a transplant recipient or cancer patient, among other conditions. The effect of the treatment was even more pronounced in people who received the drug within three days of symptom onset, consistent with other antiviral medications for COVID-19.  

The study was done in partnership with the Pontifical Catholic University of Minas Gerais, Brazil, where first-author Dr. Gilmar Reis and his team recruited the majority of participants and helped analyze the data. The study was also done in collaboration with Dr. Edward Mills, at McMaster University, and Professor Jeffrey Glenn at Stanford University. 

This study was supported by generous donors to UHN Foundation.

This site uses cookies to provide you with a great user experience. By continuing on our site, you accept use of cookies. For more information, please visit our privacy policy.


Facebook Twitter LinkedIn Instagram YouTube