(Reuters) – A Chinese experimental coronavirus vaccine being developed by the Institute of Medical Biology under the Chinese Academy of Medical Sciences was shown to be safe in an early stage clinical trial, researchers said.

In a Phase 1 trial of 191 healthy participants aged between 18 and 59, vaccination with the group’s experimental shot showed no severe adverse reactions, its researchers said on Tuesday in a paper https://www.medrxiv.org/content/10.1101/2020.09.27.20189548v1 posted on medRxiv preprint server ahead of peer review.

The most common adverse reactions reported by the trial participants were mild pain, slight fatigue and redness, itching and swelling at the injection site.

The candidate also induced immune response.

“All the data obtained in this trial support the safety and immunogenicity of this inactivated vaccine and are encouraging with regard to further studies of its efficacy in the future,” the paper said.

China has inoculated hundreds of thousands of essential workers and other groups considered at high risk with other vaccines, even as clinical trials had not been fully completed, raising safety concerns among experts.

China has at least four experimental vaccines in the final stage of clinical trials.

(Reporting by Miyoung Kim; Editing by Robert Birsel)

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