Who needs Paxlovid now? New guidelines suggest only highest-risk groups should get COVID drug

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If you consider yourself at a higher risk of serious illness from COVID-19 — because of your age, or maybe due to preexisting health issues — you might assume you'll be able to get treatment with Paxlovid when the time comes.

And you might assume the steep cost of the antiviral drug would be automatically covered by your provincial health plan.

But all that might change. There are new Canadian recommendations for who should actually get Paxlovid at this point, guided by a growing body of research suggesting the drug's life-saving benefits now apply to a narrower definition of high-risk individuals.

The expert committee for the Canadian Agency for Drugs and Technologies in Health (CADTH), the body providing advice for the country's publicly funded health care systems, released draft recommendations earlier this year which offer fresh guidance for how drug plans should cover the treatment.

It stipulates Paxlovid should only be reimbursed for patients in two scenarios: If someone is severely immunosuppressed (such as organ transplant recipients) or moderately immunosuppressed (such as someone undergoing cancer treatment, individuals with advanced HIV infections, or anyone with moderate immunodeficiencies).

Simply being older or unvaccinated — both factors long thought to hike someone's risk of serious illness or death from COVID — didn't make the cut.

The recommendations were provided to drug plans on April 11 as part of a negotiation process during which provinces decide whether or not to follow suit.

Multiple medical experts said if provincial decision makers do choose to align with the committee's suggestions, Canadians would only be eligible to get Paxlovid covered if they meet the narrow criteria for severe or moderate immunosuppression. 

Those potential changes may come as a surprise to many Canadians who've long been eligible under broader provincial guidelines — including some that currently allow people as young as 60 to access the drug based on their age and other related risk factors.

But multiple experts told CBC News that who is truly high-risk now, four years into the pandemic, has changed. And narrowed eligibility is based on the latest research into how well the drug works for various groups, said University of British Columbia researcher Colin Dormuth, whose own findings helped inform the CADTH recommendations.

"The risk of something bad happening to you because of COVID-19 is now very low," Dormuth said.

In the early years after SARS-CoV-2 first struck, the arrival of Pfizer's oral antiviral drug — a combination of the medications nirmatrelvir and ritonavir — was hailed as a game-changer. 

But its rollout was marred by controversy. There were reports of symptom "rebound" after the five-day treatment, which was later found to happen whether or not people took the drug. Some physicians also questioned who actually benefited from Paxlovid as the pandemic evolved. And, perhaps not surprisingly given all that debate, there was often low uptake, which left hundreds of thousands of treatments sitting unused across Canada.