A nasal-spray Covid-19 vaccine developed by the University of Hong Kong in collaboration with Xiamen University and Beijing-based Wantai BioPharm has been given the green light by mainland authorities.
Wantai BioPharm said the nasal
vaccine had gained approval from the Chinese National Medical Products Administration.
The pharmaceutical company said it aims to make 200 million doses of the
vaccine in the coming six months.
But the nasal
vaccine is subject to approval by Hong Kong before being used in the SAR, HKU said.
A government pandemic adviser, Yuen Kwok-yung, who took part in the research, said it can induce protection at virus entry sites, meaning it may stop the virus from entering the nasal and throat.
"It does not require injections," Yuen said. "Intramuscular injection
vaccines can induce systemic immunity, including neutralizing antibodies and T lymphocyte response in the blood but not at the nasal and throat mucosa."
Another HKU microbiology professor, Chen Honglin, said the HKU
vaccine is an excellent complement to
vaccines that require injectio.
"The nasal
vaccine is particularly acceptable to persons who are afraid of needles, such as children. All we need is a syringe with a special tip to produce a mist and does not require an inhalation device," Chen said.
He added that the priority group for taking this
vaccine may include the elderly and other high-risk people with underlying illnesses.
HKU said the
vaccine has undergone phase one, two and three clinical trials in the mainland, Hong Kong and overseas, including South Africa, Vietnam, Philippines and Columbia.
"The
vaccine is found to be safe in all three phases of the clinical trials. In the phase three clinical trial, the
vaccine is shown to have over 80 percent protective efficacy against Omicron variant in the population previously vaccinated by inactivated
vaccine and 55 percent effective in the unvaccinated population," it said.
Yuen said the HKU research team is continuing to update the nasal
vaccine for new
Covid variants, including the recent Omicron variant with high transmission.
But the current
vaccine developed with the original
Covid strain can still protect people from Omicron, he added.
The HKU research on the nasal
vaccine received HK$20 million from the SAR government under the Health and Medical Research Fund scheme and another US$5.89 million (HK$45 million) from the Coalition for Epidemic Preparedness Innovations.
Wantai BioPharm said the nasal
vaccine was given the go-ahead for clinical trials by the National Medical Products Administration in August 2020.
The first and second phase of clinical trials was conducted in the mainland and Hong Kong, while the third phase was in South Africa, the Philippines, Colombia and Vietnam.
The company said that the
vaccine is effective against the Omicron variant and can also protect those who are aged above 60.