China to allow vaccine-mixing for Covid-19 booster shots

‘Optimal immunisation combination’ to come soon, says head of China’s Covid-19 vaccines task force
Faster vaccination of the elderly and booster doses in focus as country seeks way out of strict pandemic controls

Coronavirus pandemic

Zhuang Pinghuiin Beijing

Published: 7:00am, 17 Nov 2021

Why you can trust SCMP

China will allow the mixing of Covid-19 vaccines for its booster shots drive, with an “an optimal immunisation combination” to be introduced very soon, a senior health official said.

The new strategy will help to reduce severe illness and deaths from Covid-19 and win the country time to adjust its strict pandemic controls, National Health Commission official Zheng Zhongwei told state broadcaster CCTV on Monday.

China has thus far prohibited the mixing and matching of vaccines, or sequential immunisation, despite studies around the world on its effectiveness and some countries recommending such a regimen.

02:01

China considers mixing Covid-19 vaccine types to boost effectiveness

“Whether boosting with the same or a different technology, the levels of [neutralising] antibodies will grow significantly in both cases,” Zheng, head of the government task force on Covid-19 vaccine development, told CCTV.

“While sequential boosting increases levels of neutralising antibodies even more, [using] the same technology is relatively better tolerated.”

Neutralising antibodies are an indicator of immediate immunity protection against a virus.

“We have also done a series of follow-up studies on the … different technical routes and it seems that safety is still guaranteed,” Zheng added.

“We believe that we will achieve better results in the prevention of severe illness and death by boosting immunisation with the same or different technological platforms, regardless of [coronavirus] variants. So we will introduce an optimal combination of booster vaccines … and I think we should see the results soon.”

Zheng Zhongwei says China will introduce an optimal combination of booster vaccines. Photo: Reuters

China had administered 2.38 billion doses of Covid-19 vaccines as of Monday, and more than three-quarters of its population have been fully vaccinated.

Vaccine immunity wanes over time and a booster dose is needed for the elderly and immunocompromised, effectiveness studies have shown. Hence, China is seeking to boost its vaccination drive with the hopes of building herd immunity as part of conditions to relax its tough zero-Covid control measures.

06:05

As more countries ditch ‘zero-Covid’ policy, why is China opting to ‘wait and see’?

Nearly 38 million Chinese had received booster shots as of earlier this month. All received a dose of the same technology out of the four approved vaccines in China – two inactivated vaccines from Sinopharm and another from Sinovac, as well as a viral vector variety from Tianjin-based CanSino Biologics.

CanSino is likely to benefit from the possible strategy change on booster doses, as its single-dose shot is the only approved vaccine to use a different technology from the inactivated varieties.

In a statement last week, CanSino said trials had shown that its booster dose could induce higher levels of neutralising antibodies than inactivated vaccines.

Chinese study says mixed vaccine booster produced stronger response

Zheng’s remarks also offer hope for possible regulatory approval for an mRNA vaccine jointly developed by Germany’s BioNTech and China’s Fosun Pharma.

Shanghai-based Fosun has been licensed to distribute and locally produce the vaccine, which is being marketed globally by Pfizer. Requested trials and technical review in China were complete and an administrative review was pending, according to Fosun in July.

Some countries where inactivated vaccines were initially used – such the United Arab Emirates, Brazil and Indonesia – have offered mRNA or viral vector vaccines as boosters.

Residents queue for a booster shot in Beijing. Photo: AFP

Meanwhile, a domestically developed mRNA vaccine undergoing global late-stage trials has added another group of human trials in China to study its safety and effectiveness as a booster dose six months after a full course of inactivated vaccines. This vaccine is being co-developed by the Academy of Military Medical Sciences with Yunnan Walvax Biotechnology and Suzhou Abogen Biosciences.

Zheng said in the CCTV interview that, in spite of the high vaccination rate in China, the immunisation campaign was being held back by low uptake among the elderly, who are at much higher risk of serious illness and death from Covid-19.

“By accelerating vaccination rates among the elderly and providing booster doses … we can truly reduce the rate of severe illness and mortality associated with Covid-19,” he said.

“Only in this way will we be able to take the initiative and gain time to adjust our national strategy for the prevention and control of the pandemic.”