The company making a Covid-19 vaccine with China’s state-owned manufacturer Sinopharm, said on Wednesday that its shot is 79.34 per cent effective and they are seeking to get approval to start distributing the first coronavirus drug in China.
The vaccine is already being used in several countries as global Phase 3 trials continue. As different trials progress, fragmentary efficiency data have been released, but this is the first indication from the company behind the drug.
The efficacy rate, based on an interim analysis of Phase 3 clinical trials, is lower than the 86 per cent rate for the same vaccine announced by the United Arab Emirates on December 9, based on preliminary data from trials there. The company did not elaborate on the divergence in results but said further data would be released in time.
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Turkish researchers said on Thursday that their interim results from a Covid-19 vaccine developed by China's Sinovac Biotech showed 91.25 per cent efficacy, only to see a confusing readout the same day from Brazil, which said the vaccine's efficacy was between 50 per cent and 90 per cent.
Health experts said that piecemeal data without sufficient detail could undermine confidence in vaccines.
While the efficacy of the China-developed inoculations trails the more than 90 per cent success rate of rival vaccines from Pfizer and its partner BioNTech, or Moderna, it points to progress China has made in the global race to develop successful Covid-19 vaccines.
China, whose President Xi Jinping pledged to make its vaccines a global public good, has won several large supply deals with countries including Indonesia and Brazil – the most populous countries in South-East Asia and Latin America respectively.
But detailed efficacy data is yet to be released by any of China’s drug makers.
"I think it's very positive news. The results for other Covid vaccines were also released initially in very short press releases, and within a few weeks more details were provided," said Benjamin Cowling, a public health professor at the University of Hong Kong.
Experts said that it is still early to conclude how successful the Sinopharm vaccine is.
"Data can only be interpreted when key details, such as the study design, number of participants, period of observation and number of cases, are described," said Ooi Eng Eong, an immunology professor at the National University of Singapore.
The Sinopharm vaccine is among the five most advanced candidates from China in terms of development and has been used in its emergency use programme that has vaccinated hundreds of thousands of people since July.
Its developer, Beijing Biological Products Institute, a unit of Sinopharm subsidiary China National Biotec Group, said that it had applied to the National Medical Products Administration for conditional approval of the vaccine.
CNBG has another vaccine in late-stage trials and both have been approved for emergency use in China despite studies not yet being complete.
The approval request in China came as Britain on Wednesday approved a second Covid-19 vaccine, a shot developed by the University of Oxford and AstraZeneca, as the country battles a major winter surge driven by a new variant of the virus.