Two Chinese Vaccines Less Effective Against South African COVID-19 Variant, Study Finds

Chinese researchers have reported that two vaccines developed in China can elicit an immune response against the COVID-19 variant first identified in South Africa but at reduced levels.

Sera from 12 trial participants inoculated with vaccines developed by China National Pharmaceutical Group (Sinopharm) or Chongqing Zhifei Biological Products were tested against the coronavirus variant first identified in South Africa.

Both vaccines generated neutralizing titers, but with a “slight reduction” against the South Africa variant compared with the original SARS-CoV-2 virus and the D614G mutated strain, which is the current dominant form of the coronavirus worldwide, according to nonpeer-reviewed results from the study posted on the preprint server BioRxiv.

Sinopharm’s inactivated vaccine was cleared in China through a conditional authorization in early January (DID, Jan. 4) and it has also been approved for emergency use in the United Arab Emirates, Bahrain and elsewhere. But the company has yet to release full data from its phase 3 interim analysis, such as the number of participants enrolled in the study or the number of adverse events, causing speculation about whether its reported 79.3 percent vaccine efficacy can be trusted.

Even less is known about the Chongqing Zhifei vaccine, which is currently being evaluated in a phase 3 trial in China and other Asian countries.

Click to read the study: bit.ly/39OAdGp. ― Jason Scott