China’s COVID-19 vaccine candidate BBIBP-CorV shows encouraging results

China’s COVID-19 vaccine candidate BBIBP-CorV  shows encouraging results

A COVID -19 vaccine candidate named BBIBP-CorV developed by the Chinese researchers has recently been reported safe and to elicit immune response when tested in a small early-phase human trial, according to study published in the journal The Lancet Infectious Diseases.

The trial included participants aged between 18 and 80 years and noted that antibody responses were induced in all the recipients. The researchers highlighted that participants aged 60 and over took 42 days before antibodies were detected when compared with 28 days for participants aged 18-59. Antibody levels were also lower in those aged 60-80 years compared with those aged 18-59, they said.

The phase 1 of the study had healthy volunteers divided into two groups. The first group had 96 participants aged between 18 and 59 years and a second group of 96 volunteers aged between 60 years and 80 years. Within each group, the vaccine was tested at three different dose levels, with two vaccinations administered on day 0 and 28. A fourth group within each age group were given two doses of a placebo vaccine.

In the second phase of the study, 448 participants aged between 18 and 59 years were randomly assigned to receive either one 8 microgram shot of vaccine or placebo or two shots of 4 microgramme vaccine or placebo.

The greatest antibody responses were elicited by two 4 microgram doses of the vaccine at either days 0 and 21 or 0 and 28, according to the researchers.

”Our findings indicate that a booster shot is necessary to achieve the greatest antibody responses against SARS-CoV-2 and could be important for protection,” said the researchers. However, the study had a limitation in that they did not include children and adolescents aged under 18 years.

The BBIBP-CorV vaccine is developed from an inactivated SARS-CoV-2 virus that was isolated from a patient in China and grown in the laboratory using cell lines. The virus is inactivated using a chemical called beta-proprionolactone for inclusion in the vaccine. BBIBP-CorV also includes an aluminium hydroxide adjuvant, which boosts immune responses.

The trial was not designed to assess vaccine efficacy, so it cannot reveal whether the antibody responses induced by BBIBP-CorV are sufficient to protect from SARS-CoV-2 infection, wrote the researchers.

“Protecting older people is a key aim of a successful COVID-19 vaccine as this age group is at greater risk of severe illness from the disease,” said Professor Xiaoming Yang, one of the authors of the study, from the Beijing Institute of Biological Products Company Limited, China.

“However, vaccines are sometimes less effective in this group because the immune system weakens with age. It is therefore encouraging to see that BBIBP-CorV induces antibody responses in people aged 60 and older, and we believe this justifies further investigation,” he added.

The vaccine named BBIBP-CorV is being developed by the Beijing Institute of Biological Products, a subsidiary of China National Biotec Group (CNBG). The BBIBP-CorV vaccine is one of the top 10 coronavirus vaccine projects in the world that have entered phase III clinical trials. Three of China’s vaccine candidates are in phase III trials, according to WHO.

Currently, 42 potential COVID-19 vaccines are undergoing clinical trials in China. These vary in type and include DNA plasmid vaccines, inactivated virus vaccines, adenovirus-vectored vaccines, RNA vaccines, protein subunit vaccines and virus-like particle vaccines, they said. Some of these have already been shown to be safe and to elicit immune responses in early phase clinical trials.