China's Sinovac Biotech has applied for conditional commercial approval of its COVID-19 vaccine in the country on February 3, the company said Friday. 

The company released research data from the phase-3 of CoronaVac. In Turkey, the results showed the two-dose vaccine to be 91.25 percent effective in preventing COVID-19, Sinovac said. 

In Brazil, the vaccine trial results showed a 50.65-percent overall efficacy, while it is 83.7 percent effective in mild cases that needed treatment and 100-percent effective in preventing severe or death cases.

The Beijing-based biopharmaceutical company has been conducting phase-3 research among 25,000 people in Brazil, Chile, Indonesia and Turkey since last July. In Brazil and Turkey, the research evaluated the efficacy of CoronaVac in the general group and high-risk group of the medics who treat COVID-19 patients.

The WHO's efficacy threshold is 50 percent. Currently, based on released data among all leading vaccines, the efficacy of the U.S.-made Pfizer-BioNTech and Moderna vaccines reached about 95 percent, Russia's Sputnik V 91 percent, and UK's vaccine AstraZeneca 70 percent. China's first conditional commercial COVID-19 vaccine Sinopharm has an efficacy of 79 percent.