This photo taken on May 29, 2021 shows vials of Sinopharm's COVID-19 vaccine at Dhaka Medical College Hospital in Dhaka, Bangladesh. (PHOTO / XINHUA)

BEIJING - A Wuhan-based affiliate of China National Pharmaceutical Group (Sinopharm) said the start of operations at a new factory will raise the annual production capacity of its COVID-19 vaccine to at least 1 billion doses.

The announcement marks a step toward state-backed Sinopharm's annual capacity target of 3 billion doses for its COVID-19 vaccines

The Wuhan Institute of Biological Products made the announcement in a statement released late on Monday through social media. It did not specify when it will operate the factory at full capacity.

Still, the announcement marks a step toward state-backed Sinopharm's annual capacity target of 3 billion doses for its COVID-19 vaccines.

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The Beijing Institute of Biological Products, another Sinopharm affiliate whose shot gained emergency-use approval from the World Health Organization, has a factory with annual capacity of 1 billion doses and is also building a new facility.

China has approved four COVID-19 vaccines from domestic makers Sinopharm, Sinovac Biotech Ltd and CanSino Biologics Inc  for general public use, and three other vaccines for emergency use.

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Sinovac, whose COVID-19 vaccine capacity is 2 billion doses per year, on Tuesday said it has supplied over 600 million doses at home and abroad as of the end of May.