Health Canada approves Pfizer’s COVID-19 therapeutic
Health Canada has approved Pfizer’s COVID-19 therapeutic for use in adults 18 and older, paving the way for the distribution of a potentially lifesaving drug at a time when the country’s hospitals are overwhelmed.
Pfizer’s Paxlovid, an antiviral prescribed by a doctor and administered in pill form, is designed to help the body fight off the SARS-CoV-2 virus, reduce symptoms from an infection and shorten the period of illness. Pfizer’s laboratory studies indicate that the drug is likely to work against the Omicron variant, which has become the dominant form among new cases in Canada.
The product has been hailed as a pandemic “game changer” by some doctors because it could reduce hospitalizations and deaths among COVID-19 patients. An effective pill that’s easy to self-administer at home could relieve some of the pressure on the health care system and change the trajectory of the pandemic, experts say.
Canada has placed an order for an initial quantity of one million treatment courses. Some of that supply will start to arrive in the coming weeks. With global interest in antivirals running high as the Omicron variant wreaks havoc, Pfizer is promising to churn out 120 million courses of the treatment by year’s end.
Dr. Theresa Tam, Canada’s chief public health officer, said today the federal government is working to “firm up a delivery schedule” and officials are hoping the pills will be available “as soon as possible.”
Tam said the Public Health Agency of Canada (PHAC) is working with its provincial and territorial counterparts to determine how best to distribute antivirals, which are expected to be in shortly supply for the foreseeable future.
“This treatment, the first treatment taken orally and at home, will be in high demand,” she said. “We anticipate supply at the beginning will not be great anywhere.”
After months-long clinical trials, Pfizer reported in November that Paxlovid reduced the risk of hospitalization or death by an impressive 89 per cent compared to a placebo in non-hospitalized high-risk adults with COVID-19.
The product, which doesn’t prevent infection, has been authorized by Health Canada for use in high-risk adults with mild or moderate COVID-19 symptoms.
A person should start taking Paxlovid no more than five days after symptoms start, which could be “one of the key challenges of these antivirals,” Tam said.
‘An important tool’
“They have to given really early in the course of the clinical course. Not easy, but everybody needs to give it a good try because it could be an important tool going forward,” she said. “It could potentially blunt the severity of the virus, which is a a key goal.”
Health Canada said Pfizer’s pills should only be used by patients who have tested positive on a SARS-CoV-2 viral test. Such tests are currently in short supply in some provinces and territories. If a PCR test is not available, Tam said a positive result on a rapid antigen test would also suffice.
This drug regimen could be useful for people who have underlying conditions that increase the risk of hospitalization and death related to the coronavirus, such as heart disease or diabetes.
Health Canada has warned, however, that the product shouldn’t be used while a patient is on any of a long list of other drugs, including common medications used to treat erectile dysfunction, high cholesterol and seasonal allergies, among others.
“If you’re on certain medications, you have to be careful when using this drug,” Tam said, urging prescribers to review contraindications before writing a script for Paxlovid.
Pfizer’s treatment is meant to be taken as 30 pills over five days. Patients take three pills at a time: two of Pfizer’s pills and one of a low-dose HIV drug known as ritonavir, which helps Pfizer’s drug remain active in the body longer.