Today's lunchtime news on BBC radio 4 reported that the BMA, which represents the majority of the country's GPs, has criticised the decision to extend the time between first and second Covid vaccinations to 12 weeks, so that more people can get some protection earlier. Apart from inconvenience to practices and patients, stretching the vaccination interval to this extent breaches the dosing regime approved by the UK drug regulator MHRA. winsfordguardian.co.uk/news...
In the case of the Oxford-Astrazeneca vaccine though, a 12 week gap may - fortuitously - make the vaccine more effective. The approved dosing regime is two full doses of vaccine 3 weeks apart, which corresponds with the 62 percent efficacy measured in the main patient cohort of the phase 3 clinical trial. The newly proposed regime, two full doses of vaccine 12 weeks apart, is more like that given (inadvertently) to the smaller patient cohort, which indicated 90 percent efficacy.
Despite its objections, though, the BMA has stressed the urgent need to ramp up the vaccination programme bma.org.uk/bma-media-centre...
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..however, after a second dose there is only a small and non-significant reduction in vaccine effectiveness
