A candidate vaccine developed by Chinese researchers for the novel coronavirus has shown to be safe and effective in the first two phases of clinical trials, its leading developer said on Tuesday.

None of the 1,120 people who took part in the trials showed serious side effects after receiving the vaccine, the first inactivated vaccine for the coronavirus approved for clinical trial globally, China National Biotec Group said in a statement.

In addition, high-concentration antibodies for the virus have been produced in the bodies of all those who received the vaccine, demonstrating its effectiveness, it said.

The clinical trials started on April 12 in Wuzhi county, Henan province, and the volunteers were divided into groups to receive different doses of the vaccine and at intervals of 14, 21 and 28 days.

All the volunteers, aged between 18 and 59, are healthy, and each received two shots, the company said.

The company said the clinical result has been the best among all other similar COVID-19 vaccines being researched in China.

"The result is inspiring, and the data on the vaccine's safety and effectiveness have greatly increased our confidence in winning the war against the epidemic," the company said.

Meanwhile, the company is working to advance a Phase 3 clinical trial of the vaccine in partnership with overseas counterparts, and has reached agreements with enterprises and institutes from other countries, it said.

The company has also completed building a workshop with high biosafety standards that can produce enough COVID-19 vaccine in case of emergency, it said.

Research and development of COVID-19 vaccines has been progressing rapidly in China, following the outbreak at the end of last year.

Last month, researchers announced that another COVID-19 candidate vaccine, under development by institutes including the Beijing Institute of Biotechnology, showed safety and potential in protecting humans from the coronavirus, based on the preliminary clinical trial.