Three new Chinese vaccines as potential “boosters” against Omicron and Delta

Events in China over the next 6 weeks will include the Chinese New Year Spring Festival traditional mass travel (“Chunyun”) and the Winter Olympics, Feb. 4-20. COVID-19 outbreaks of Omicron and/or Delta variants are occurring in multiple cities in different provinces, e.g., Tianjin (near Beijing), Anyang, Xuchang, Yuzhou, Zhejiang, Xi’an and Hong Kong. China will likely start to give booster doses of COVID-19 vaccines that are of a different type (platform) than what most of the country’s population has already received, i.e., two doses of the inactivated whole virus Sinovac or Sinopharm vaccines.

The first new Chinese vaccine is the Sinopharm recombinant protein spike (S). It was studied in Abu Dhabi in the United Arab Emirates and has been approved in that country by their Ministry of Health as a booster after two doses of the traditional Chinese Sinopharm inactivated whole virus (2019) vaccine. This UAE approval was based on a study in Abu Dhabi that has not yet been peer-reviewed. This study reported that this new Chinese recombinant protein vaccine “booster dose” was safe and stimulated higher neutralizing antibody levels than did a third dose of the same Sinopharm inactivated whole virus against four variants: Omicron, Delta, Beta and Alpha.

The second new Chinese vaccine is a candidate mRNA vaccine being tested by two companies (Walvax Biotechnology and Abogen Biosciences) based in Suzhou, China. The mRNA vaccine study is a large Phase III study, but no results are available yet on ClinicalTrials.gov.

The third new Chinese vaccine is an inhaled version of an existing intramuscular vaccine. This is the CanSino Biologics inhaled adenovirus-vectored vaccine, as reported in the South China Morning Post on Jan. 12. A 13,000-person study of the inhaled CanSino Biologics adenovirus-5 vectored vaccine or placebo among volunteers who have received one intramuscular dose of this vaccine began in November 2021. It is scheduled to be completed in the spring of 2022 and is described at ClinicalTrials.gov.

Lastly, although not a new vaccine, the BioNTech mRNA vaccine is still awaiting approval for use in mainland China. In Hong Kong, however, it was reported in the South China Morning Post that this German-made vaccine would be available widely in January 2022.

I am not aware of any Omicron-specific vaccines being made by China. Meanwhile, Pfizer announced today (Jan. 12) that they would make 100 million doses of an Omicron-specific vaccine by this spring.