The Pfizer/BioNTech Covid-19 vaccine can remain stable at temperatures found in refrigerators for up to one month, the medicines watchdog has announced.

Yesterday (20 May), the Medicines and Healthcare products Regulatory Agency (MHRA) revised the conditions of authorisation for the mRNA vaccine, after a recent assessment of additional data showed that the vaccine can be stored in conditions of 2-8°C from five days to one month if unopened.

Previously, unopened thawed vials of the Pfizer vaccine could only be kept at 2-8C in the fridge for five days.

In a letter sent to vaccine sites (20 May) NHS England said that the new, more flexible storage time will minimise vaccine wastage and will make it easier to align clinics with availability and delivery of the vaccine.

According to a new temporary standard operating procedure (SOP) from the NHS Specialist Pharmacy Service, vaccine sites will receive new thaw labels for vaccine vials next week, which reflect the extended shelf-life.

It said that current vaccine stock should only be relabeled if it is ‘operationally necessary’ – i.e. if it will not be used within the next 120 hours.

The NHS England letter added that the superintendent or responsible pharmacist should ensure that healthcare professionals operating alongside them on site are ‘aware of this development’ and that ‘the implications for vaccine supplies already in their possession are carefully understood’.

The Pharmacist understands that some pharmacy sites have been commissioned to deliver the Pfizer vaccine as well as the Oxford/AstraZeneca vaccine, with some expected to begin vaccinating the public with Pfizer vaccine this week.

Dr June Raine, MHRA chief executive, 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.’

Similarly, Emily Lawson, England Vaccine deployment lead and Dr Keith Ridge, the chief pharmaceutical officer at NHS England — who signed the letter sent to vaccine sites — said they welcomed the move which ‘brings additional flexibility to our vaccination programme.’

Last month, pharmacies were advised to cancel any AstraZeneca jab appointments for people aged under 30, following updated guidance from the Joint Committee on Vaccination and Immunisation (JCVI) that said this age group should be offered an alternative.

The JCVI guidance – which has also now been extended to those aged 30-39 – came after an MHRA review into reports of rare blood clots following the first vaccine does of the AZ vaccine, which looked at 79 cases of thrombosis, 19 of whom had died.