Pfizer-BioNTech's updated vaccine to protect against a recently circulating variant of COVID-19 is authorized, Health Canada said on Tuesday.

Novavax uses a protein-based vaccine strategy, which means people getting the vaccine receive a protein made by the virus that their body’s immune systems then see as foreign and mount responses against. mRNA vaccines, by contrast, include snippets of mRNA genetic material from the COVID-19 virus’ spike protein.

On Aug. 22, the U.S. Food and Drug Administration announced the approval of a new Novavax COVID vaccine, as well as updated versions of the Pfizer-BioNTech and Moderna vaccines. According to NPR, this latest vaccine is already being distributed and administered across the country.

With the approval of Moderna's updated COVID-19 vaccine, doctors are hoping the shots will be available soon and Albertans will opt to roll up their sleeves to get one.

Pfizer's and Moderna's formulas have been the go-to on pharmacy shelves, but Novavax remains an important option.

The company reported Health Canada authorized the use of its Spikevax KP.2 shot for those aged six months and older. Last month, the U.S. Food and Drug Administration also gave approval for the vaccine, as well as updated shots from Pfizer ( PFE) and BioNTech ( BNTX ).