Health Canada has formally approved Moderna’s updated COVID-19 vaccine targeting the Omicron variant.
The vaccine, which has been approved for use in adults 18 years and older, will become the first COVID-19 vaccine available in Canada that targets Omicron in addition to the original strain of the coronavirus.
In a decision summary released Thursday, Health Canada said the new vaccine shows “significantly higher responses” to the Omicron BA.1 virus compared to Moderna’s original coronavirus vaccine, officially branded as Spikevax.
Although the updated vaccine was developed to target the Omicron BA.1 variant, Health Canada says clinical trials suggest the new vaccine still elicits a “stronger immune response” against the newer Omicron – BA mutations. 4 and BA.5 – which are now dominant.
“The results of exploratory analyzes suggest that a second boost with Spikevax Bivalent would provide a superior neutralizing antibody response against BA.4/5 compared to a second boost with Spikevax Original,” reads part of the decision.
Health Canada also reports that “no new safety issues have been identified in studies compared to the currently approved Spikevax mRNA vaccine.”
The National Advisory Committee on Immunization recommends that the updated vaccine be offered to adults who are recommended to receive a fall booster dose.
NACI says the vaccine could also be offered to adolescents aged 12 to 17 with “moderately to severely immunocompromised conditions” and those with high social risk factors.
WATCH: Health Canada Chief Medical Advisor Dr. Supriya Sharma says updated vaccine will be effective against Omicron
Health Canada authorizes Moderna’s bivalent COVID-19 vaccine
Dr. Supriya Sharma, Health Canada’s chief medical adviser, says Moderna’s new bivalent vaccine will target both the old variant of COVID-19 and Omicron, the newer one. It has been approved for use in Canadians 18 years of age and older.
The updated vaccine is a combination of two strains, also known as “bivalent” shots. Contains both the original vaccine formulation and protection against the original Omicron BA.1 variant.
Moderna’s new injection will be delivered in doses of 50 micrograms. Half of its content is directed at the original coronavirus strain, while the other half is directed at Omicron.
An initial shipment of 780,000 doses of the updated vaccine will arrive in Canada on Friday, Health Minister Jean-Yves Duclos said. An additional 10.5 million doses will be delivered at the end of September.
Deliveries to provinces and territories, which oversee vaccine administration, will begin next week.
Duclos urged Canadians to sign up for booster shots quickly as summer ends.
“This fall is going to be a challenge, with the return of the flu and other respiratory illnesses and people moving home,” Duclos said at a press conference Thursday afternoon.
Vaccines for new strains of Omicron may be forthcoming
Both Moderna and Pfizer have developed even newer bivalent vaccines targeting the Omicron BA.4 and BA.5 strains, but the companies have not yet submitted these products for Health Canada approval.
Njoo said that in choosing to approve Moderna’s BA.1-focused vaccine, the government considered the tools it has now “versus what might happen in the future.”
“At the end of the day, we’re very comfortable with the fact that we have a good bivalent vaccine,” Njoo added.
The US Food and Drug Administration on Wednesday announced its approval of bivalent vaccines from Pfizer and Moderna that specifically target the newer Omicron BA.4 and BA.5 strains.
Dr. Supriya Sharma, Health Canada’s chief medical adviser, said the agency expects to receive a submission from Pfizer as early as next week for a bivalent vaccine targeting BA.4 and BA.5.
Moderna’s new filing for BA.4 and BA.5 is also expected in the next two weeks, Sharma said.
A Pfizer Canada spokesperson told CBC News on Wednesday that its submission to Health Canada for a bivalent vaccine targeting BA.1 is still under review and has not yet been approved.
WATCH: Infectious disease doctor says Canadians shouldn’t wait for updated boosters
High-risk Canadians urged not to wait for new reinforcements: Infectious disease specialist
Infectious disease physician Dr. Lisa Barrett is encouraged by the approval of the new bivalent vaccine targeting Omicron BA.1. She says holding off on the next, more up-to-date vaccine would be risky.
Angela Rasmussen, a virologist at the University of Saskatchewan’s Infectious Diseases and Vaccines Organization, said the approval of the vaccine is an important development in Canada’s fight against COVID-19, although the vaccine was developed for a strain that no longer circulates widely.
“I think it’s very important now that people know that the BA.1 vaccine will still really improve immunity against the variants that are circulating,” Rasmussen told CBC News.
Another expert said Canadians should not wait for the perfect and most up-to-date vaccine, as they will likely need repeated immunizations against COVID-19 in the future.
“This protection won’t last. This won’t be the last vaccine you get. So be prepared, until we have better vaccines, to get vaccinated probably every six months,” said Dawn Bowdish, an immunologist at McMaster University.