An intranasal Covid19 vaccine developed by researchers at the University of Hong Kong (HKU) in collaboration with Xiamen University and Wantai pharmaceutical has gained approval from the Chinese authorities for emergency use in the Mainland.
Wantai BioPharm announced today (Dec 5) that the nasal vaccine has obtained the critical green light from the Chinese National Medical Products Administration.
Wantai is targeting to manufacture 200 million doses (one dose per person) in the next six months.
Use of the nasal vaccine in Hong Kong is subject to approval by the HKSAR government.
"Our intranasal vaccine has the advantage of inducing protection at the site of virus entry, i.e., it may stop the virus from entering the nasal and throat mucosa. It does not require injections. 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," said Professor Kwok-yung Yuen, of the HKU research team.
Professor Chen Honglin, another member of the team, added that the HKU vaccine is therefore an excellent complement to the present injection vaccines. "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."
He added that the priority group for taking this vaccine may include elderly, high risk groups with underlying illnesses.
In February 2020, the Department of microbiology and the Centre for Virology, Vaccinology and Therapeutics (CVVT) at HKU made an intranasal influenza virus vectored vaccine seed which can protect hamsters from COVID-19.
After further investigation and production by good manufacturing practice (GMP) standard, the vaccine has undergone phase 1, 2 and 3 clinical trials in the Mainland, HKSAR and overseas including South Africa, Vietnam, Philippines and Columbia, independently.
Professor Ivan Hung of HKU led the HKSAR part of the first and second phase vaccine trial in collaboration with the HKU/QMH Clinical Trial Centre.
The vaccine is found to be safe in all three phases of the clinical trials. In the phase 3 clinical trial, the vaccine is shown to have over 80% protective efficacy against Omicron variant in the population previously vaccinated by inactivated vaccine and 55% effective in the unvaccinated population. The HKU part of the study is partially funded by the HKSAR government under the Health and Medical Research Fund scheme (20 million HKD and the Coalition for Epidemic Preparedness Innovations( CEPI 5.89 million USD).
The research team is continuing to update the nasal vaccine for new Variants of Concern (VOC) including the most recent Omicron strains. But even using the ancestral virus spike receptor binding domain, the nasal vaccine can protect against Omicron, said Professor Yuen.
Wantai BioPharm's announcement on the vaccine.
