Alberta shelves preventative COVID-19 therapy, Evusheld, as resistant variants take hold

Alberta is no longer recommending Evusheld, a preventative COVID-19 therapy, because it does not work against the latest subvariants to take hold in the province.

Evusheld has been offered to immunocompromised Albertans, including transplant patients and people undergoing some types of cancer treatment, since last May.

On Thursday, U.S. Food and Drug Administration removed its authorization for Evusheld, saying it's unlikely to be effective against the newest strains, including XBB.1.5.

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"With these newer subvariants, it just has no effect. It's hard to justify," said Dr. Alain Tremblay, a Calgary-based respirologist and member of a committee advising public health officials on COVID-19 therapies.

"Unfortunately for preventative [therapy] for people who can't [be immunized]or don't respond to the vaccine right now we're losing something and we don't have an alternative," he said.

Alberta Health Services updated its website Monday afternoon to reflect the change.

"Evusheld is now shown to be ineffective against the latest variant of COVID-19," spokesperson Kerry Williamson said in an email to CBC News.

"Alberta's decision is consistent with other provinces including Ontario, B.C. and Quebec. Clinicians can consider administering Evusheld on case-by-case basis."

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Tremblaysaid it's the latestmonoclonal antibody drug to drop off asSARS-CoV-2evolves.Sotrovimab was deemed ineffective last year.

"It's concerning because we know that there's a reasonable amount of COVID going around in the community. ... So there is a portion of the population that are immunocompromised that are losing an option to protect themselves."

According to Alberta Health, Evusheldhas been prescribed to 1,430 Albertans since it became available in the province in May.

"[With] the majority of the lineages that we have circulating right now the BQs and the XBB.1.5 there's no benefit of Evusheld against those dominant strains. And so using it right now actually doesn't make that much sense," said Dr. Lynora Saxinger, an infectious disease specialist at the University of Alberta

"The decision affects a fairly small group of people. But at the same time, it's a group of people that we are paying a lot of attention to because they are at higher risk of severe disease."

Health Canada issued a risk communication for health-care providers earlier this month but it has stopped short of shelving Evusheld altogether.

"The most recent epidemiological data inCanada(asofJanuary 1, 2023) indicate that BA.5 subvariants continue to account for more than 89%ofreported cases," a spokesperson said in a statement emailed to CBC News, adding decisions about Evusheld should consider the prevalence of variants in a geographical location and individual exposure.

Key COVID-19 treatments continue

"For treatment we're still in good shape," said Tremblay.

Antiviral treatments, such as the oral medicationPaxlovid, are still available and they continue to work against the latest subvariant, according to Tremblay.

The province said 11,900 Albertans have received Paxlovidand it has 74,600 treatment courses available.

Remdesivir, an IV drug used to treat 5,340 Albertansboth in the community and in the hospital setting, also remains effective, he said.

Meanwhile, according to Saxinger,losing Evusheldhighlightsthe importance of getting a booster shot,especially for those with weakened immune systems.

"[They] do actually have a better response with more doses," she said, noting vigilance and watching for any symptoms will be key.

"The other thing is just maintaining a low threshold of suspicion so you can be tested early and treated early if you do have exposures because there's really good data that the antivirals ... are very useful in reducing the risk of severe disease. But to do that you actually have to know that you have COVID."

AHS updated and loosened itseligibility criteria for Paxlovid and Remdesiviron Monday, saying they're now considered "guidelines" and notedhealth care providers can assess patients on a case-by-case basis.