A second made in China vaccine against COVID-19 has been approved for mass inoculations by China's healthcare regulator.
The experimental "CoronaVac" chemically-inactivated whole vaccine developed by Sinovac Biotech Ltd. was granted authorization for public use in China Saturday by the National Health Commission (NHC).
Sinovac said NHC approval was based on the two-month results from phase three clinical trials in Indonesia, Brazil and Turkey. Final analysis of the data obtained from this clinical trial hasn't been made public, however,
Sinovac noted CoronaVac had earlier received emergency use authorizations from Indonesia, Turkey, Brazil, Chile, Colombia, Uruguay, and Laos.
Prior to Saturday's government approval, CoronaVac was one of three Chinese-made candidate vaccines that have been used since September 2020 to inoculate essential workers throughout the country.
More than one million Chinese were vaccinated under an emergency use program authorized by the NHC.
The most popular of these vaccine candidates are CoronaVac and "BBIBP-CorV" developed by state-owned China National Pharmaceutical Group Corporation (also known as Sinopharm). Both are two-dose vaccines.
CoronaVac is said to provide sufficient protection against COVID-19 while amenable to storage in ordinary household refrigerators. A study published in the peer-reviewed medical journal, The Lancet Infectious Diseases, found CoronaVac triggered a quick immune response to COVID-109 infections. The level of antibodies produced by CoronaVac, however, was lower in people that had recovered from the disease.
A key advantage enjoyed by CoronaVac over other vaccines such as those from Pfizer/BioNTech and Moderna is its tolerance for temperatures not in the sub-zero range.
CoronaVac is a more attractive option compared to the mRNA (synthetic messenger RNA) vaccines from Moderna and Pfizer/BioNTech because it can be stored at normal refrigerator temperatures of 2 to 8 degrees Celsius (36°F to 46°F).
It also remains stable for up to three years, said Gang Zeng, a Sinovac researcher involved in the study. The study said CoronaVac "offers some advantages for distribution to regions where access to refrigeration is challenging."
China has already shipped millions of doses of CoronaVac and the "BBIBP-CorV" vaccine to developing countries. BBIBP-CorV was developed by state-owned China National Pharmaceutical Group Corporation (also known as Sinopharm).
Phase three clinical trials show BBIBP-CorV with 79.3% efficacy and 99.5% antibody positive conversion rate. These results are better than the 50% standard set by the World Health Organization.
