NO MORE, ALTA. The emergence of a new coronavirus variant has raised concerns about a fifth wave of COVID-19 in Canada, spurring renewed interest in both vaccines and treatments for those who are sick.
Several different types of therapy for COVID-19 have been approved for use in Canada, including several treatments being tested as part of clinical trials nationwide.
Below are some of the treatments available in Canada.
GIVE UP
In July 2020, Health Canada authorized the use of remdesivir, an antiviral drug originally used to support Ebola treatment, to treat COVID-19 patients with severe symptoms. such as pneumonia or those who need extra oxygen to breathe.
This is the first drug approved to treat COVID-19 in Canada.
According to Health Canada, remdesivir is recommended for use in Canadians 12 years of age and older who weigh at least 40 kg. Treatments must be administered intravenously and used only in healthcare settings where patients can be closely monitored.
“This is a drug that inhibits the virus itself; many of the other treatments we’ve seen used or tried to use to treat COVID-related illness are already in the immune system. “, infectious disease expert Dr Lisa Barrett of Dalhousie University in Halifax explained to CTV News Channel at the time.
“However, this drug is designed to directly inhibit the virus itself and has been used or tested for use in other viral infections before.”
In November 2020, the World Health Organization (WHO) updated its ongoing COVID-19 drug guidance to advise against the use of remdesivir, citing a lack of evidence that the drug affects the risk of die from COVID-19 or require mechanical ventilation. However, this does not affect Health Canada’s decision to allow the use of the drug.
Some of the latest studies on remdesivir, published in April 2021, show that it appears to be as safe and effective when used in children with COVID-19 as it is in adults, with a low incidence of adverse effects. serious side effects.
BAMLANIVIMAB
Approved for use by Health Canada in November 2020, bamlanivimab is the first monoclonal antibody approved in Canada for use in the treatment of COVID-19.
The drug mimics the immune system’s ability to fight viruses and was developed by AbCellera Biologics Inc. in Vancouver with support from the federal government.
It is recommended to treat adults and children 12 years of age and older who weigh at least 40 kg. The drug is used to treat people who are at high risk of developing serious COVID-19 complications or being hospitalized, but not people with severe respiratory illness.
However, in April 2021, Health Canada issued a warning about “potential treatment failure” for the Canadian-made drug, saying it may not protect against infection. infection from several variants.
According to Health Canada, bamlanivimab “shows reduced activity against SARS-CoV-2 variants” with the E484K and L452R mutations. This includes variant B.1.351 first identified in South Africa, variant P.1 first found in Brazil, variant B.1.427/B.1.429 reported in California and variant B .1,526 was first identified in New York.
While countries around the world have been using this drug, almost none of Canada’s 26,000 doses have been used. Doctors say this is because a plan on how to use the drug has never been put in place due to the fact that it must be given intravenously within the first 10 days of infection.
CASIRIVIMAB AND IMDEVIMAB
In June 2021, Health Canada authorized the use of casirivimab and imdevimab to be used together as monoclonal antibody therapy. Similar to bamlaniximab, it is used to treat mild to moderate COVID-19 in adults and children 12 years of age and older who are at high risk of hospitalization or COVID-related complications.
WHO has advocated the use of antibodies in some high-risk patients, and they are widely used in the United States to treat COVID-19. However, usage in Canada remains unclear.
Quebec received a small amount of the monoclonal antibody cocktail in October.
Doctors in Hamilton, Ont. also piloting the province’s first outpatient monoclonal antibody clinic using casirivimab and imdevimab, citing data showing that the therapy reduces hospitalizations by 71% and mortality by 7% in COVID-positive patients are at high risk.
SOTROVIMAB
Another monoclonal antibody treatment, sotrovimab, was approved for use in Canada in July 2021. The injection is used to treat mild to moderate COVID-19 in adults and children Children 12 years of age and older are at increased risk for hospitalization or complications related to COVID.
On Wednesday, health officials in Alberta revealed that they had administered sotrovimab to unvaccinated COVID-19 patients 65 years of age and older.
The province’s chief medical officer, Dr Deena Hinshaw said at a news conference: “Treatment is being rolled out across the province in phases, starting with those most at risk of serious outcomes. , such as hospitalization”.
“I would like to stress that sotrovimab is not a replacement for the COVID-19 vaccine… because a vaccine is the most effective way to prevent serious consequences from this disease.”
This comes amid news that laboratory tests and a study in hamsters have shown that the antibody cocktail sotrovimab works against viruses that are biologically engineered to carry certain mutations. characteristic variable of the newly discovered Omicron variant.
TREATMENT OF SLEEP
Molnupiravir
Health Canada says it is still reviewing data related to an experimental pill by drugmaker Merck, which the company says could halve hospitalizations and deaths among patients with the disease. COVID-19.
Molnupiravir, an oral antiviral agent taken twice daily within five days of the onset of symptoms, has shown modest benefit and potential safety issues in trials. Most experts who advocate for the treatment emphasize that the drug should not be used by anyone who is pregnant and suggest extra precautions before prescribing it, such as a pregnancy test for women. in childbearing age.
The drug targets an enzyme the coronavirus uses to replicate itself, inserting errors into its genetic code that slow its ability to spread and take over human cells – leading some independent experts to question whether The drug may have the potential to cause mutations that lead to birth defects or tumors.
The drug has not been tested in vaccinated people.
On November 30, the U.S. Food and Drug Administration endorsed the drug’s use in adults with mild to moderate COVID-19 illness who face an increased risk of complications. higher, including older adults and people with conditions such as obesity and asthma. The UK has also authorized its use.
Health Canada did not provide a timeline for completing the review.
PAXLOVID
Pfizer also recently submitted clinical data to Health Canada on an oral drug it hopes could be used to treat mild to moderate cases of COVID-19 in adults.
Similar to molnupiravir, the pill is designed to block the action of an enzyme in the COVID-19 virus that is needed for its replication. Part of the pill uses ritonavir, an existing drug that has been used in combination with other antiviral drugs before.
In a randomized, double-blind study of 380 patients, the risk of being hospitalized or dying from COVID-19 was reduced by 89% in patients who took Pfizer within three days of starting the drug, the drug’s maker said. show COVID. -19 symptoms, compared with the placebo group.
It’s not clear how long it could be before Health Canada makes a ruling on whether Pfizer’s pill meets their standards.
– With files from Alexandra Mae Jones, Brooklyn Neustaeter, The Canadian Press and The Associated Press
.
