China has made marked progress in developing different types of COVID-19 vaccines, including two nucleic acid vaccines soon to enter late-stage clinical trials overseas, a senior health official said on Tuesday.

Zheng Zhongwei, head of China's COVID-19 vaccine development task force, said during a news briefing that all five vaccine development technologies pursued by Chinese researchers have seen at least one product entering human trials.

Among them, one mRNA vaccine and one DNA vaccine – both belong to the category of nucleic acid vaccine products – have each obtained approval to launch third-stage clinical trials overseas, he said.

Three domestic inactivated vaccines have gained conditional market approval and two have been granted emergency use authorization, he said.

One recombinant subunit vaccine has been approved for emergency use, while three others are undergoing third-stage clinical trials and five others are going through early-stage trials.

One adenovirus-based viral vector vaccine has obtained conditional approval, and three other products have entered the initial stages of trials.

One viral vector vaccine based on weakened flu virus is going through second-stage clinical trials, and is preparing for third-stage trials overseas.