China’s CanSino Biologics on Wednesday sought to distance its Covid-19 vaccine from concerns that products made using a similar technology could be linked to rare events of serious blood clotting.
The company said no serious adverse events related to blood clots had been reported among the almost 1 million doses of its Covid-19 vaccine that had been administered to date. The product is licensed in China, Pakistan, Mexico and Hungary.
The statement came after the US Food and Drug Administration on Tuesday called for a pause in the roll-out of a vaccine made by American firm Johnson and Johnson, pending its review of six cases of severe blood clots among the 6.8 million people injected with it.
The US recommendation came on the heels of a finding last week from the EU’s European Medicines Agency (EMA) of a possible link between a vaccine made by British-Swedish firm AstraZeneca – of which more than 30 million doses have been administered in Europe – and rare cases of blood clots.
While the technology is the same for all four products, their developers used different formulations of adenoviruses to construct their vaccines.
CanSino’s product is based on a common cold virus known as Ad5, while Johnson and Johnson used a rarer human adenovirus. The Gamaleya Institute used a combination of the two for its Sputnik V vaccine, and AstraZeneca relied on a virus found in chimpanzees.
