AstraZeneca and British Prime Minister Boris Johnson on Thursday defended the effectiveness of the company's Covid-19 vaccine after regulators in Germany said it should not be given to over-65s.
A spokesperson for the UK-based company said the latest clinical trial data for its vaccine, developed with Oxford University, "support efficacy in the over 65 years age group".
The company is awaiting a decision from the EU's medicines regulator, the spokesperson added.
Johnson meanwhile told reporters that the UK's own regulator had established "that they think the Oxford/AstraZeneca vaccine is very good and efficacious, gives a high degree of protection".
A panel of scientific experts in Germany said the vaccine should only be used for "persons aged 18 to 65 years old based on available data", citing "insufficient data" to assess its efficacy for older people.
Britain has been using the Oxford/AstraZeneca jab along with another developed by Pfizer/BioNTech across all older age groups as it bids to immunise the most vulnerable 15 million people by mid-February.
Mary Ramsay, head of immunisations at the government agency Public Health England, also backed the AstraZeneca vaccine for older recipients.
"Both the AstraZeneca and Pfizer/BioNTech vaccines are safe and provide high levels of protection against Covid-19, particularly against severe disease," she said.
"There were too few cases in older people in the AstraZeneca trials to observe precise levels of protection in this group, but data on immune responses were very reassuring," Ramsay added.
"The risk of severe disease and death increase exponentially with age -- the priority is to vaccinate as many vulnerable people as possible with either vaccine, to protect more people and save more lives."