OTTAWA — AstraZeneca has asked Health Canada to review a new long-acting antibody combination that could be used to prevent symptomatic COVID-19.

If approved, it would be the first antibody protection of its kind in Canada.

The company says its clinical trials showed the antibody treatment was well tolerated and reduced the risk of developing symptomatic COVID-19 by 77 per cent compared to a placebo.

"This is an important option, especially for vulnerable populations like those who are immune-compromised and often aren't able to mount a protective response following vaccination," said Dr. Alex Romanovschi, vice-president of scientific affairs for AstraZeneca Canada.

"With this Health Canada filing, we are one step closer to providing an additional long-lasting option to help protect against COVID-19 alongside vaccines."

The drug is a combination of two long-acting antibodies derived from cells donated by COVID-19 patients. The antibodies would be administered as two injections, one immediately after the other, and could offer up to a year of protection from the virus.

While a vaccine effectively teaches the body to make its own antibodies over a short period of time, AstraZeneca's product would deliver ready-made antibodies to immediately start fighting off the virus.

They could be used in concert with COVID-19 vaccines, Romanovschi said, or be offered to people who have allergies or otherwise can't tolerate a vaccine.

"Another area where we can look at is individuals at increased risk of infections. For example, health-care professionals or long-term care workers. Those individuals might also benefit from additional protection," he said.

The company says preliminary findings show the antibodies neutralize recent COVID-19 variants, including the Delta and Mu variants.

The latest data has been submitted to Health Canada as part of a rolling review, which allows companies working on COVID-19 drugs and vaccines to submit data as it becomes available.

Health Canada has said all COVID-19 vaccine and drug submissions will be prioritized and reviewed on an expedited timeline.

AstraZeneca is studying the combination as a potential treatment for COVID-19 as well.

This report by The Canadian Press was first published Nov. 3, 2021.

Laura Osman, The Canadian Press