Health Canada to authorize Pfizer’s antiviral COVID-19 drug

OTTAWA —
Health Canada is expected to authorize the use of Pfizer’s COVID-19 antiviral treatment Paxlovid on Monday, CTV News has confirmed.

The official announcement is expected to come from the federal health agency at 11 a.m. EST.

Pfizer submitted clinical data for the oral medication that can be used to treat mild to moderate cases of COVID-19 in adults, on Dec. 1, 2021.

The government has a deal in place with the pharmaceutical giant securing access to an initial one million doses of the therapeutic drug.

Responding to recent calls from the provinces for a swift rollout of this medication in the face of an expected surge in Omicron hospitalizations, the federal government has vowed that delivery of the drug will happen in short order.

Health Minister Jean-Yves Duclos and Procurement Minister Filomena Tassi will be holding a press conference to discuss the rollout of this treatment at 1:30 p.m. EST.

It is intended to be given to adults ages 18 and over who have a confirmed case of COVID-19 and are at an increased risk of developing severe illness.

In November 2021, Pfizer released the results of their Phase 2/3 trials for the drug, stating that they had found the pill to significantly reduce hospitalization and death in COVID-19 patients. 

Pfizer said that in a randomized, double-blind study of more than 380 patients, there was an 89 per cent reduction in the risk of being hospitalized or dying of COVID-19 in patients that received Pfizer’s pill within three days of displaying COVID-19 symptoms, compared to the study group that received a placebo.

According to Pfizer, Paxlovid is designed to block the activity of an enzyme in SARS-CoV-2 that is essential for the virus to replicate itself, and also help to slow the breakdown of the pill’s ingredients in order to help combat the virus for longer. Part of the pill uses ritonavir, an existing drug that has been used in combination with other antiviral medications before.

The drug is what is called a “protease inhibitor antiviral therapy”, a type of medication that has largely been used before to treat HIV/AIDS and hepatitis C.

Health Canada has also been reviewing an experimental pill from drugmaker Merck, called molnupiravir, since mid August. The federal government also has a contract to purchase 500,000 of Merck’s antiviral medication, with an option for 500,000 more pending regulatory approval.

In late December, the U.S. Food and Drug Administration issued an emergency use authorization for both Pfizer and Merck’s drugs.

With files from CTV News’ Annie Bergeron-Oliver, Alexandra Mae Jones and Sarah Turnbull