GPonline reported earlier this month that the European Medicines Agency had approved the longer storage period for EU countries - and the MHRA said earlier this week it was considering a similar update to UK advice.
The regulator has now confirmed that the Pfizer COVID-19 vaccine - which along with the Moderna vaccine is one of two products recommended as first-choice options for patients aged under 40 in the UK - can be kept for a full month at normal fridge temperatures.
The updated advice could prove a major boost for vaccination sites currently working through patients in their 30s, offering greater flexibility around storage of supplies of vaccine.
Vials of the Pfizer/BioNTech vaccine are stored at ultra-low temperatures until use - but the changes announced by the MHRA extend the time for which it can be kept once thawed. The regulator said the updated advice was 'expected to make storage easier and possible for a wider range of health facilities'.
MHRA chief executive Dr June Raine said: 'We are pleased to confirm that, having rigorously assessed the additional data submitted to us by the company, we have now approved more flexible storage conditions for the Pfizer/BioNTech vaccine.
'Up until now, the Pfizer vaccine had to be administered within five days of being removed from ultra-low temperature freezers.
'Now that the jab can be stored at normal fridge temperatures for up to 31 days, it can be used in a wider range of healthcare settings, giving patients greater access to the Pfizer vaccine.'