The CoronaVac vaccine developed by Chinese drug maker Sinovac has once again been proved highly effective in a large-scale Phase 3 trial in Chile, according to a new study published in the New England Journal of Medicine on Wednesday.

Results of a nationwide mass vaccination campaign in the country from February 2 to May 1 showed that the inactivated vaccine is 65.9 percent effective against symptomatic COVID-19, 87.5 percent in the prevention of hospitalization, 90.3 percent against ICU admission, and 86.3 percent against COVID-19 related deaths.

The research involved 10.2 million participants aged 16 years and above. The results suggest that it offers very similar protection to the people over 60 years as it does for other groups.

The vaccine, which can be stored and transported at 2-8 degrees Celsius, has been approved for emergency use in more than 20 countries and has been in Phase 3 trials since mid-2020 in Brazil, Indonesia, Chile and Turkey.

Its efficacy against hospitalization was reported as over 90 percent in studies in both Brazil and Indonesia. And the latest results of the trial in Turkey, which was published in the top medical journal The Lancet on Thursday, showed it's 83.5 percent effective against symptomatic COVID-19.

It was also approved for emergency use by the World Health Organization on June 1, which means it meets international standards for safety, efficacy and manufacturing.