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China’s Vaccine Push in Developing Countries Suffers Setback After Brazillian Tests Reveal Sinovac’s Shot Only 50% Effective

A package of the experimental vaccine test for the COVID-19 coronavirus is pictured at the Quality Control Laboratory at the Sinovac Biotech facilities in Beijing. NICOLAS ASFOURI / AFP

China’s ambitious global drive to provide developing countries with affordable COVID-19 vaccines suffered a major setback on Tuesday following new test results from Brazil that revealed Sinovac’s CoronaVac vaccine to be only 50% effective.

The findings from the Butantan Institute, a São Paulo-based public institute that is the first to complete late-stage trials of the CoronaVac vaccine, came as a big surprise because just last week the institute said Sinovac’s shot was 78% effective and offered total protection against severe cases of the disease.

The revised results raise new concerns about the quality and efficacy of Chinese-made vaccines, especially since Chinese pharmaceutical companies have been far less transparent in their test regimes than vaccine manufacturers in the U.S. and Europe.

“This will have profound implications domestically [in China] and internationally,” said Yanzhong Huang, a senior fellow for global health at the Council on Foreign Relations in New York. “From the very beginning, China has raised people’s expectations about the effectiveness of China-made vaccines.”

To be clear, these findings only apply to CoronaVac. Other Chinese vaccines have higher efficacy levels — at least as far as we know. Nonetheless, this is potentially very worrisome news for countries in Africa and other developing regions that have been pushed to the back of the line for access to C19 vaccines and are now counting on Chinese jabs to fill the void.

Also, it’s important to note that CoronaVac trials produced starkly different results in other countries: 91.25% in Turkey and 65% in Indonesia.

Sinovac has not commented on the Butantan Institute’s latest findings.

What Experts Are Saying About the Latest Sinovac Efficacy Results

  • LACK OF TRANSPARENCY: “It is confusing when the group [Sinovac] that has access to the data from Indonesia, Turkey, and Brazil makes no official comment as its trial data are presented piecemeal. Are these authorized or unauthorized? If they are authorized, why doesn’t the company comment? We don’t know how the analysis was done. We also don’t know if the analyses can be combined. Is this an official number that Sinovac will stand by?” — Jerome Kim, director-general of the International Vaccine Institute(SOUTH CHINA MORNING POST)
  • GOOD ENOUGH?:  “If the vaccine has an efficacy rate around 50%, it’s going to be hard to justify including it in the national vaccination program… But if we have a society that doesn’t have the means to acquire all of the vaccines it needs, you can see a scenario where authorities would say, ‘Fifty percent protection is still better than nothing’” — Iván Darío Vélez, an infectious disease expert at Colombia’s University of Antioquia (THE WALL STREET JOURNAL)

Chinese State’s Media “Yes… But…” Response to Sinovac’s Lower Efficacy Rate in Brazil

The initial reactions from Chinese state media to the revised findings that Sinovac’s CoronaVac COVID-19 vaccine is only 50% effective, based on clinical trials in Brazil, was surprisingly mild.

The normally bombastic Global Times tabloid calmly acknowledged that CoronaVac’s results were lowered but then added that the vague claim vaccine is “100% effective in preventing severe cases.” 

Global Times quoted certain unnamed “experts” saying that CoronaVac’s efficacy rate was “good enough.”

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