Samples of the COVID-19 inactivated vaccine are seen at a vaccine production plant of China National Pharmaceutical Group (Sinopharm) in Beijing, capital of China, April 10, 2020. Photo:Xinhua

One of China's COVID-19 vaccine candidates has proven effective in protecting monkeys from the novel coronavirus, according to a report released on May 6 in Science magazine, in the world's first report on animal trial results for COVID-19 vaccine candidates.

According to the report, the researchers isolated 11 viruses from 11 patients, among whom five were from China, three were from Italy, one was from Switzerland, one was from the UK and one was from Spain.

Animal trials showed that a purified inactivated COVID-19 vaccine candidate (PiCoVacc) the researchers developed can induce novel coronavirus neutralizing antibodies in mice, rats and non-human primates. These antibodies potently neutralized 10 representative novel coronavirus strains, indicative of a possible broader neutralizing ability against the virus strains circulating worldwide, according to the report.

Researchers gave two different doses of the vaccine to eight rhesus macaques. Three weeks later, the group introduced the novel coronavirus into the monkeys' lungs and none developed a full-blown infection.

Analysis of the macaques suggests that the vaccine candidate is safe, and the data supports the rapid clinical development of vaccines for humans.

Clinical trials with PiCoVacc, as well as other COVID-19 vaccine candidates, are expected to begin later this year, according to the report.

The report was jointly authored by a research team led by Qin Chuan, the director of the Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, and those from Beijing-based company Sinovac Biotech.

An inactivated COVID-19 vaccine candidate jointly developed by the two sides was already delivered into clinical trials on April 16.

The Global Times has learned that at least seven COVID-19 vaccine candidates have been put into clinical trials, including four developed by China, one by the US, one by the UK and one co-developed by the US and Germany.

Some other countries have also announced plans to deliver their vaccine candidates into clinical trials, including one developed by Canadian company Symvivo Corporation.