Coronavirus in China: home-grown mRNA vaccine works better against all existing variants, mice study shows
- Study led by former top virologist reveals results of comparing mRNA-based hybrid vaccine with Omicron-specific shot in mice
- The team’s Delta-Omicron jab can produce broader neutralising antibodies against all variants, study indicates
The Gao-led research team earlier developed an mRNA-based hybrid vaccine seen to offer better protection against both the Delta and Omicron variants in mice.
Chinese mRNA booster fights Omicron 4 times better than Sinovac: study
Their Delta-Omicron vaccine produced broader neutralising antibodies against all types of variants, according to the study first published in peer-reviewed scientific journal Cell last month.
In a follow-up study published last Wednesday in Cell Research, another peer-reviewed journal, the team further examined the efficacy of the hybrid vaccine as a booster dose.
Vaccinated mice were boosted with either of the two shots. The hybrid booster was shown to induce a stronger immune response, including for the currently circulating Omicron subvariants BA.4 and BA.5.
“The variant-adapted multivalent mRNA vaccine strategy … could accelerate the development of vaccines that address circulating and emerging Sars-CoV-2 variants,” the researchers concluded.
A study in May found that the three-dose vaccine was nearly 76 per cent effective against symptomatic Covid-19 infections and about 88 per cent effective against severe-to-critical infections for six months following full vaccination.
That vaccine is effective against variants including Alpha, Delta and Kappa, according to the team, and has been approved for emergency use in China, Uzbekistan, Indonesia and Colombia.
ZF2001 is the only recombinant protein vaccine among the eight Chinese vaccines currently in use.
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Gao, the former head of the Chinese Centre for Disease Control and Prevention, is now with the Savaid Medical School, under the University of Chinese Academy of Sciences. He stepped down from his CDC position in July upon reaching the retirement age of 60.
He sparked controversy in April last year when he said China was considering mixing Covid-19 vaccines or adjusting the dosage “to solve the problem of low efficacy for its existing vaccines”, but later said his comments had been misunderstood.
He had been referring to international efforts at improving vaccine efficacy, Gao told nationalist tabloid Global Times.