By The Nation
Three are at the most advanced stage of Phase 3 trials – two vaccines being developed by China’s Sinovac, and one by Oxford University and the UK’s AstraZeneca.
"Meanwhile, another 21 Covid-19 vaccines are under Phase 1 or Phase 2 human trials, including prototypes developed in China by CanSino Biological and the Beijing Biological Institute of Biotechnology, and in the US by Moderna and the National Institute of Allergy and Infectious Diseases," said Dr Yong.
Another 140 prototype vaccines are being tested in animals, four of them in Thailand – two at Chulalongkorn University, one at Bionet Asia, and one under joint research between Mahidol University and the Government Pharmaceutical Organisation.
"This shows that countries worldwide are trying to overcome Covid-19," he said.
Third-phase trials are testing Covid-19 vaccines and placebo vaccines on large groups of people in countries with high risk of infection, said Yong, adding that Thailand and China have to conduct trials in other countries now that their domestic infection rates have fallen.
Phase 3 testing will also compare prototypes to ensure that any new vaccines match the efficacy of the most effective vaccine found, he added.