Regulators gave conditional approval for Sinovac Biotech Ltd’s shot, CoronaVac, on Friday, clearing the way for general use, The National Medical Products Administration announced in a statement Saturday

The Sinovac vaccine has already been sold to at least 10 other countries and is being administered to people in at least five other countries. In China, the shot was given emergency approval last July, allowing people such as medical workers and employees of state-owned firms to receive it.

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The conditional approval means the vaccine can now be given to the general public, though research is still ongoing. The company will be required to submit follow-up data as well as reports of any adverse effects after the vaccine is sold on the market.

It is the second locally made vaccine to be given conditional approval. Beijing authorized the state-owned Sinopharm's vaccine in December.

China has previously said any COVID-19 vaccine will be free for its public, with the government footing the bill. Sinovac declined to give a figure for the price of each dose.

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Both Sinovac’s shot and Sinopharm’s shot are two-dose inactivated vaccines, relying on traditional technology that makes it easier to transport and store than Pfizer's vaccines, which requires ultracold storage. That could make a difference for developing countries that have fewer resources.

Sinovac's vaccine however, has also been subject to intense scrutiny and criticism for lack of transparency, largely in part owing to the different efficacy data in different countries across the world. Officials in Turkey, where part of the stage 3 clinical trials were staged, have said the efficacy rate was 91.25%.

But in a much bigger trial in Brazil, officials there initially announced an efficacy rate of 78%, but revised that down to just over 50% after including mild infections. The Brazil segment of the trial enrolled 12,396 volunteers, and recorded 253 infections, the company said in a statement Friday.

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So far the company has only released stage 1 and stage 2 data for its vaccine.

Full clinical trial data for the stage 3 trials will be released later in a peer-reviewed journal, said Pearson Liu, a spokesperson for the company.

Global health authorities have said any vaccine that is at least 50% effective would be useful. The flu vaccine is generally around 50% effective. Experts have also said that it is meaningful that those who fall ill despite taking the vaccine should still be less likely to suffer serious symptoms.

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Its stage 3 clinical trials were held in Brazil, Chile, Indonesia and Turkey, with a total of 25,000 volunteers.