Switzerland has said trials of AstraZeneca’s coronavirus vaccine did not produce clear data, especially around its efficacy in older people, as it withheld approval of the jab.
Drugs regulator Swissmedic called for more efficacy and quality data before it green lights the shot, which is currently being used in the UK and won approval in the European Union last week.
Separately, the country separately announced it had ordered millions more Covid-19 vaccine doses from other manufacturers.
Switzerland, which has already ordered 5.3 million doses from AstraZeneca, said it was waiting on results from trials of the shot in North and South America involving tens of thousands of people.
"As soon as the results have been received, a temporary authorisation according to the rolling procedure could be issued at very short notice," Swissmedic said in a statement, adding it was necessary to get additional data about safety, efficacy and quality.
"The data currently available do not point to a positive decision regarding benefits and risks," it said.
AstraZeneca and its partner, Oxford University, have defended their vaccine, saying it had 76 per cent efficacy against symptomatic infection for three months after a single dose, which increased if the second shot is delayed.
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However, some European countries are restricting it to certain age groups, citing a lack of data in particular in older people.
The Swiss government said it had signed a deal with Germany's Curevac and the Swedish government for the delivery of 5 million vaccine doses, a preliminary pact with US vaccine maker Novavax for 6 million doses, and secured a further 6 million doses from Moderna.
These new orders bring total Swiss vaccine orders to more than 30 million doses, enough to vaccinate its 8.6 million population about twice over under a two-dose regimen.
Further talks with additional developers are under way for even more shots, the government said.
"The idea behind procuring vaccines from different manufacturers is to make sure that sufficient doses of an approved vaccine are available to the public even if there are delivery problems," the Federal Health Ministry said.
Additional reporting by Reuters
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