Researchers in Toronto have been given the green light to launch Canada’s first clinical trial into whether the antiviral drug favipiravir can help fight COVID-19 outbreaks in long-term care homes that have been devastated by the coronavirus.
Favipiravir, sold under the brand name Avigan, is typically used to treat viruses, like influenza, and works by stopping a cell’s potential to become a factory for the virus and spread infection, according to the researcher leading the study.
“If we have a drug that you reliably use to stop outbreaks after they have started, that would be extraordinarily helpful,” Dr. Allison McGeer, a senior clinician scientist at the Lunenfeld-Tanenbaum Research Institute at Sinai Health, told Global News.
Nursing homes account for over 80 per cent of Canada’s COVID-19 deaths, according to Canada’s chief public health officer, Dr. Theresa Tam, with facilities in Quebec and Ontario hit particularly hard.
Japan approved the drug for influenza treatment in 2014 and added it to the country’s stockpile of emergency medical supplies in case of an influenza outbreak, according to the Halifax-based biopharmaceutical company Appili Therapeutics Inc., which is sponsoring the drug trial.
McGeer said the drug is similar to the experimental drug remdesivir, which has been found to shorten the recovery time of COVID-19 patients from 15 to 11 days. But unlike remdesivir, which is administered intravenously, Favipiravir can be taken in tablet form, which makes it ideal for long-term care homes, according to McGeer.
She is looking to enroll about 760 subjects, both residents and staff, at 16 long-term care homes in Ontario.
And with no vaccine currently available and a looming second wave of the virus approaching, she is hoping that favipiravir could work as effectively in stopping COVID-19 as oseltamivir, sold under the brand name Tamiflu, is in stopping influenza.
“It’s obviously a lot to ask of residents and their social decisionmakers to be in a trial during a pandemic,” she said. “But if it works, it will be brilliant. And the only way to find out if it works is to do the trials.”
Ontario long-term care facilities have been devastated by outbreaks of COVID-19, with more than 7,000 residents and staff becoming infected and over 1,700 residents deaths, according to the provincial government.
“Given the strikingly high fatality rate from COVID-19 in long-term care facilities, there is a particularly urgent need for randomized trials that explore ways of protecting the most vulnerable members of our society,” Peter Jüni, a senior epidemiologist at St. Michael’s Hospital and co-principal investigator, said in a statement.
The partially blinded, randomized trial — first approved by Health Canada last month — will evaluate the efficacy of favipiravir in nursing home residents compared with placebo to prevent COVID-19 outbreaks.
However, as the goal of the trial is to see whether the antiviral drug can control outbreaks of COVID-19 once they begin, McGeer said researchers are looking to enrol all 250 homes in Greater Toronto Area over the next six months so facilities can make quick decisions about whether they want to participate in the trial if they experience an outbreak.
Two small studies from researchers in Wuhan, China, published in February showed that favipiravir demonstrated some effectiveness against SARS-CoV-2, the virus that causes COVID-19.
And Russia announced in May that it had approved a version of favipiravir to treat COVID-19 after its trials found it could reduce the length of illness from 11 to four or five days.
McGeer said although there is limited research on the drug, there is only one way to find out if it’s effective: conduct the trials.
“It’s almost like it would be too good to be true. It makes me anxious just thinking about it,” McGeer said. “But, you know, that’s why we are doing it — because it might be true.”