In the second of Andrew Polmear’s Covid reports, he looks at the Oxford AstraZeneca vaccine and the over 65s.
A friend has just emailed to say that she’s delighted that she’s had her first Covid vaccination – but disappointed that it was the Oxford/AstraZeneca version. She’s in her 70s and I guess she’s heard that a number of European countries will not be using the Oxford/AZ vaccine in people over 65. Indeed, President Macron of France has been the most outspoken, saying that “it’s quasi-ineffective in the over 65s” Yet our own Medicines and Healthcare Products Regulatory Agency, and the EU equivalent, have approved its use in all adults. So what’s going on?
The problem is that the Oxford study began with patients under 55 years old. They wanted to prove that it was safe in younger patients before giving it to the elderly. Once it was clear that it was safe they included adults of all ages. But when they reported their first results only 2 patients over 65 had the disease. Neither had been given the vaccine but the numbers were too small to say that that proved that the vaccine worked in the older patient. They could, however, say that President Macron was wrong to say it didn’t work. All that can be said is that they hadn’t proved it did work.
So why has the Oxford/AZ vaccine been approved for all ages? There are two reasons:
- The researchers measured the antibodies in the blood following administration of the vaccine. Subjects over 65 had a strong immune response, as measured in the lab. It was not quite as strong as in younger subjects but it was plenty strong enough.
- All other studies so far reported have shown that older people are protected by the other vaccines. Especially reassuring is the vaccine made by J&J which uses the same technology as the Oxford/AZ vaccine. It would be very odd if the Oxford/AZ vaccine didn’t behave in the same way.
My belief is that, like President Macron, politicians in those countries have confused ‘no evidence of benefit’ with ‘evidence of no benefit’. If the Oxford/AZ vaccine isn’t shown to be effective at all ages in the next few weeks, I’ll eat my hat.
This is an area of science where new information is coming out every day. By the time this article is published it may already be out of date. And please bear in mind that it is the opinion of one retired GP, not a leading scientist. Andrew regrets that he cannot enter into correspondence with individual readers.