In coronavirus vaccine race, Chinese and Oxford trials produce immune responses, offering hope in pandemic
- Phase-two trial by team of Chinese scientists ‘induces significant neutralising antibody responses’, paper in peer-reviewed The Lancet reports
- Study out of Britain’s Jenner Institute finds antibodies are still high up to two months after vaccine administered
The Chinese scientists have completed phase two of their trial, published in The Lancet medical journal on Monday, which found that one injection of either a low or medium dose of the vaccine “induced significant neutralising antibody responses to live Sars-CoV-2”, the name for the novel coronavirus. An earlier phase-one trial of the vaccine had produced immune responses, but the latest trial was widened to include individuals aged 55 or older, given their higher risk of death from the Covid-19 virus.
Scientists at Oxford University share promising news on coronavirus vaccine trials
“Single-dose immunisation with the vaccine induced rapid onset of immune responses within 14 days, and significant humoral and cellular immune responses within 28 days in the majority of the recipients,” the team of Chinese scientists, led by Zhu Fengcai from the Jiangsu Provincial Centre for Disease Control and Prevention (CDC) and Guan Xuhua from the Hubei Provincial CDC, wrote.
Their results showed the vaccine, developed by the Beijing Institute of Biotechnology and Chinese vaccine maker CanSino Biologics, had “a good safety profile”.
Most of the participants given the vaccine at a centre in central China’s Wuhan reported mild or moderate reactions, most commonly fatigue, fever and headache. Seventy-four per cent of the 129 individuals who received the lower dose and 72 per cent of those who received the medium dose reported at least one negative reaction but none had serious adverse reactions.
The most common side effects from the Oxford vaccine included fatigue, which was reported by 70 per cent of participants, and headache, reported by 68 per cent. Other reactions included muscle ache, malaise and feeling feverish but there were no serious adverse events.
While there were limitations to the Oxford study – including that participants were capped at age 55 and the short-term follow-up after vaccination – the scientists said the results supported the “large-scale evaluation of this candidate vaccine” for an ongoing phase-three programme.
“Phase-three trials are now under way in Brazil, South Africa, and the UK and will evaluate vaccine efficacy in diverse populations,” the Oxford study said.
The Chinese research team said their results supported moving to a phase-three effectiveness trial with the lower dose of their experimental vaccine, but also acknowledged study limitations, including that the entire participant population was from Wuhan.
They also noted that their participants were not exposed to the coronavirus after vaccination, so it was not known if they would be immune to infection.