CanSino Biologics Inc. (“CanSinoBIO”) announced that its Recombinant Novel Coronavirus Vaccine Adenovirus Type 5 Vector (“Ad5-nCoV”, trade name: Convidecia™) has been approved by the Joint Prevention and Control Mechanism of the State Council of China (“State Council”) as a heterologous booster, making it the first adenovirus-vectored vaccine to be included in the heterologous vaccination program in China.
According to the State Council, for those aged 18 and above who have completed a 6-month vaccination schedule using inactivated COVID-19 vaccines, and those who have not been administered a homologous booster, being administered CanSinoBIO’s Convidecia™ as a heterologous booster can significantly increase the neutralizing antibody levels with proven safety.
Heterologous booster vaccination refers to the use of vaccine boosters from different technology platforms from the prime vaccines, which could improve the overall immune response and enhance protection against other variants.
Recent clinical trial results from a study on heterologous vaccination conducted by the Jiangsu Provincial Center for Disease Control and Prevention showed that after two-dose priming with an inactivated COVID-19 vaccine, a single dose of Convidecia™ as a heterologous booster could induce neutralizing antibody levels at 197.4 (95% CI 167.7, 232.4) 14 days post vaccination, five times higher than a homologous booster of inactivated vaccine, with neutralizing antibody levels at 33.6 (95% CI 28.3, 39.8).
According to a recent study jointly published by China’s CAS Key Laboratory of Pathogenic Microbiology and Immunology, the Institute of Microbiology of the Chinese Academy of Sciences and others, those who had two doses of inactivated vaccine and then received Convidecia™ as a heterologous booster 4 – 8 months later were found to have neutralizing antibody levels against the prototype strain that were 7 times higher than those boosted with recombinant protein vaccines. The study found that for the Omicron variant, Convidecia™ generates neutralizing antibody levels 6 times and 3 times higher than the groups given inactivated vaccines and recombinant protein vaccines, respectively.
In addition, administering Convidecia™ as a booster can also induce a significant CD8+T cellular immune response, which could rapidly kill virus-infected cells and reduce the chance of severe illness and death, providing both humoral and cellular immunity.
A recent interim guidance for heterologous COVID-19 vaccination from the World Health Organization recommended that for people who have initial administration with inactivated COVID-19 vaccines, they may choose either adenovirus-vectored or mRNA vaccines as the subsequent booster doses. In November 2021, the Ministry of Health of Argentina recommended CanSinoBIO’s Convidecia™ as a booster for people who have received inactivated vaccine for at least one month, including those aged 50 years old and above.
CanSinoBIO is committed to providing timely and broad immune protection, making its vaccines more accessible to regions with insufficient storage facilities and medical resources, and reducing the burden placed on healthcare systems and medical workers. Currently, Convidecia™ is approved in more than ten countries, including China, Pakistan, Mexico, Ecuador, Chile, Argentina, Hungary, Kyrgyzstan, Indonesia and Malaysia, etc.
