Oxford University/AstraZeneca vaccine authorised by MHRA

The JCVI has subsequently recommended that as many people on the priority list as possible should be offered a first vaccine dose as the initial priority (as opposed to prioritising completing the 2 dose courses) as it protects the most amount of people in the shortest time.

SPS commentary:

The MHRA authorisation includes conditions that the AstraZeneca (Oxford) vaccine should be administered in 2 doses, with the second dose given between 4 and 12 weeks after the first. The MHRA has also clarified that for the Pfizer/BioNTech vaccine, the interval between doses must be at least 3 weeks. For both vaccines, data provided to MHRA demonstrate that while efficacy is optimised when a second dose is administered, both offer considerable protection after a single dose, at least in the short term. For both vaccines the second dose completes the course and is likely to be important for longer term protection.

The UK Chief Medical Officers agree with the JCVI that at this stage of the pandemic, prioritising the first doses of vaccine for as many people as possible on the priority list will protect the greatest number of at-risk people overall in the shortest possible time and will have the greatest impact on reducing mortality, severe disease and hospitalisations and in protecting the NHS and equivalent health services. Operationally this will mean that second doses of both vaccines will be administered towards the end of the recommended vaccine dosing schedule of 12 weeks.

The JCVI, has also amended its previous highly precautionary advice on COVID-19 vaccines and pregnancy or breastfeeding. Vaccination with either vaccine in pregnancy should be considered where the risk of exposure SARS-CoV2 infection is high and cannot be avoided, or where the woman has underlying conditions that place her at very high risk of serious complications of COVID-19, and the risks and benefits of vaccination discussed. Those who are trying to become pregnant do not need to avoid pregnancy after vaccination, and breastfeeding women may be offered vaccination with either vaccine following consideration of the woman’s clinical need for immunisation against COVID-19.

JCVI advises that the second vaccine dose should be with the same vaccine as for the first dose. Switching between vaccines or missing the second dose is not advised as this may affect the duration of protection.

The Green Book has also been updated.


Medicines and Healthcare products Regulatory Agency

Resource links:

Statement from the UK Chief Medical Officers on the prioritisation of first doses of COVID-19 vaccines

Priority groups for coronavirus (COVID-19) vaccination: advice from the JCVI, 30 December 2020

MHRA approval page

Information for Healthcare Professionals on the Astra Zeneca COVID-19 vaccine

Green book chapter 14a (updated to include details on the Astra Zeneca Vaccine)

COVID-19 vaccination – for immediate action (for NHS Trusts)