Chinese vaccines can be upgraded for variants

China’s COVID-19 vaccines based on the inactivated virus can be upgraded to cope with new variants in about two months, the Global Times reported on Tuesday citing an expert with the Chinese Center for Disease Control and Prevention.

There are concerns that vaccines developed over the last year may be less effective against new variants of the virus discovered recently in Britain and South Africa. Moderna Inc said on Monday it would test a new booster shot aimed at the South African variant after concluding the antibody response could be diminished.

Vaccines from Sinovac Biotech and China National Pharmaceutical Group (Sinopharm), which are being used in China and overseas, contain the inactivated virus that cannot replicate in human cells. If necessary, an upgrade for China’s inactivated COVID-19 vaccine could be completed in about two months, Shao Yiming, a CDC scientist, said.

The neutralizing ability of antibodies induced by Chinese vaccines, which were developed in accordance with the variant spreading in Wuhan city in late 2019, appeared weaker against recently discovered variants in the UK and South Africa, Shao said, citing studies by Chinese vaccine companies and labs.

The redesign of inactivated COVID-19 vaccines could take longer than for vaccines based on messenger RNA (mRNA) technology, which does not require cultivating and inactivating the virus, according to Shao, who participates in technical reviews of China’s COVID-19 vaccines.

The mRNA technology is used in vaccines developed by Pfizer Inc and Moderna.