Covid-19: Chinese vaccine 'successful in mid-stage trials'

A Covid-19 vaccine developed in China has shown success in mid-stage trials, researchers have said.

There are several vaccines being developed in China, some of which are already being administered.

According to the researchers, the Sinovac Biotech vaccine led to a quick immune response during trials with an estimated 700 people.

The announcement comes after European and US vaccines reported successful data from large late-stage trials.

Three vaccines, developed in the US, Germany and Russia, have all released data suggesting efficiency of more than 90 per cent, after trials with tens of thousands of people.

Like the rest of the world, China is racing to develop a Covid vaccine, and four have entered the third and final stage of clinical trials, including the one created by Sinovac Biotech.

However, the results published in the scientific journal, The Lancet, are only from the first and second trial phases of one of those four vaccines.

According to the report, Sinovac Biotech's CoronaVac triggered a quick immune response, although the study conducted in April and May did not give a percentage of the vaccine's success rate.

Zhu Fengcai, one of the paper's authors, said the results - which are based on 144 participants in the phase one trial and 600 in the phase two trial - meant the vaccine was "suitable for emergency use". No data from the ongoing large-scale phase three trials has been published yet.

With the pandemic reported to be almost entirely under control within China, late-stage trials of the four Chinese vaccines are being conducted in Pakistan, Saudi Arabia, Russia, Indonesia and Brazil.

According to officials, nearly 60,000 people had received a vaccine by early November. Trials of the Sinovac Biotech vaccine in Brazil were briefly halted last week but resumed after the reported death of a volunteer was found to have no links to the vaccine.

At least three of the vaccines are also already being offered to essential workers as part of an emergency programme, while one was approved for the Chinese military in June.

How does it compare with the other vaccines? Over the past few days, there has been a string of promising vaccine news from around the world.

First, a German-US vaccine by Pfizer and BioNtech was reported to be more than 90 per cent effective based on late-stage trials with more than 43,000 people

Preliminary results

Then, US company Moderna said its vaccine showed 94.5 per cent efficiency, also after large late-stage trials. In both cases the results are preliminary and both vaccines have not yet been approved.

And a Russian Covid vaccine was reported to be 92 per cent effective after trials with 16,000 volunteers. It was already granted approval for emergency use within Russia in August.

Researchers behind all three of those vaccines have released data from more advanced testing stages than the Chinese vaccine. But Sinovac Biotech is conducting these same late-stage trials as well, and the fact that there is no data released on those trials does not necessarily mean that the other researchers are ahead.

The use of the vaccine candidates for emergency cases in China - like medical frontline staff - suggests authorities have a certain level of trust in the jabs.

Which of those vaccines will be first rolled out on a large scale still remains to be seen. Approval and mass production would be the next hurdles and experts caution not to expect widespread vaccination programmes before next year.?

Final results from Pfizer Inc's Covid-19 vaccine trial showed its shot had a 95 per cent success rate and two months of safety data, paving the way for the drugmaker to apply for an emergency US authorisation within days, it said yesterday.

The vaccine's efficacy rate was welcomed by experts who had already said that interim results showing Pfizer's shot was over 90 per cent effective were very encouraging.

Pfizer said there were 170 cases of Covid-19 in its trial of more than 43,000 volunteers and only eight people with the disease had been given the shot rather than a placebo, meaning the vaccine had a 95 per cent efficacy rate. Of the 10 people who developed severe Covid-19, one had received the vaccine.

"The data is very strong," said Ian Jones, a professor of virology at the Britain's University of Reading. "It's looking like a real contender."

Pfizer said it expected the US Food and Drug Administration's vaccine advisory committee to review and discuss the data in a public meeting that will likely be held in December. "We continue to move at the speed of science, and we know that everyday matters in our path to authorisation," Pfizer Chief Executive Albert Bourla said.

The final analysis comes just a week after initial results from the trial showed the vaccine, developed with German partner BioNTech SE, was more than 90 per cent effective. Moderna Inc on Monday released preliminary data for its vaccine, showing 94.5 per cent effectiveness.

The better-than-expected results from Pfizer and Moderna have raised hopes for an end to a pandemic that has killed more than 1.3 million people and wreaked havoc upon economies and daily life.

However, while some groups such as healthcare workers will be prioritised in the US for vaccinations this year, it will be months before large-scale rollouts begin.