Study Reveals Some Omicron Subvariants Can Escape From COVID-19 Vaccine Antibodies

Illustration vaccine Sinopharm. (Wikimedia Commons/Peruvian Defense Ministry)

JAKARTA - A small Chinese study detailed in the journal 'The Lancet Infectious Diseases' showed that neutralizing antibodies against several Omicron subvariants were largely undetectable, after two doses of the Sinopharm COVID-19 vaccine, with booster injections only partially recovering.

The study comes as China, which only approves locally developed COVID-19 injections, including the Sinopharm vaccine, seeks to increase vaccination rates, maintaining a 'dynamic zero COVID' policy aimed at eradicating all outbreaks. Meanwhile, many countries have adopted a learning approach to living with the virus.

The vaccine, BBIBP-CorV, is one of two Sinopharm COVID-19 vaccines approved for use in China, and is also the main injection the state-owned company exports.

Among 25 people who received two doses of BBIBP-CorV vaccine, neutralizing activity against sub-variants such as BA.2.12.1 and BA.4/BA.5 "was not or only slightly detectable", the researchers said in correspondence published on Monday. , reported Reuters June 21.

Neutralizing activity against the sub-variant was observed in only 24-48 percent of subjects who received a booster injection of BBIBP-CorV after the two-dose product, the researchers said, citing results from the group of 25 participants.

The figure increased slightly, to 30-53 percent, for those who received the third injection made by the Chongqing Zhifei Biological Products unit, another vaccine approved for use in China, according to data from another group of 30 subjects.

The study did not address the efficacy of boosters, a level that reflects how well they can lower the risk of COVID illness or death, which is typically observed in large clinical trials.