Coronavirus: Chinese inactivated vaccine candidate produces immune response, study shows
- But whether it can protect individuals against Covid-19 ‘remains unknown’, authors say
- Product developed by Sinopharm and Wuhan Institute of Biological Products
The results of the first two phases of trials appeared to show the product – developed by Sinopharm and Wuhan Institute of Biological Products – was safe, but a third phase of testing, which has started, would provide more information, the study’s authors said.
“Although the inactivated vaccine elicited robust antibody responses, whether it could protect individuals against Covid-19 remains unknown,” said the study, which was published in the Journal of American Medical Association on Thursday.
It is the first to provide clinical trial data for an inactivated vaccine for Covid 19. Inactivated vaccines consist of virus particles, bacteria or other pathogens that have been grown in culture and then lose disease producing capacity.
The Sinopharm product is one of three Chinese vaccine candidates undergoing phase three clinical trials. The new research was conducted by a team of 30 and partly supported by China National Biotec Group, a unit of Sinopharm.
The trial involved 320 healthy adults, aged 18 to 59. They were given four different kinds of injections – either a placebo, or a low, medium or high dose of the vaccine candidate.
The most common side effects were pain at the site of infection and fever, which occurred in between 6 to 25 per cent of the patients, depending on the different dosages used in the trials.
The study said all of the side effects were mild enough to not require medical treatment.
What happens next, as coronavirus vaccine trials move to a new phase?
A total of 29 Covid-19 vaccine candidates are undergoing trials around the world, according to the World Health Organisation.
Two of them were produced by Sinopharm and are undergoing phase three testing in the United Arab Emirates. Trials of other products are ongoing in Japan, Britain, the United States, India and elsewhere.
Chinese pharmaceutical firm CanSino earlier published the results of the first two stages of clinical trials of its vaccine candidate, which uses an adenovirus as a vector.
The final phase of testing involves large numbers of people being tested, with the product closely monitored for safety and efficacy. Phase one involves small trial groups, and phase two slightly larger groups.
