It is excellent news that the Medicines and Healthcare products Regulatory Agency (MHRA) has today authorised the AstraZeneca (Oxford) vaccine for deployment across the UK.
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 Joint Committee on Vaccination and Immunisation (JCVI) has subsequently recommended that as many people on the JCVI priority list as possible should sequentially be offered a first vaccine dose as the initial priority. They have advised that the second dose of the Pfizer/BioNTech vaccine may be given between 3 to 12 weeks following the first dose, and that the second dose of the AstraZeneca (Oxford) vaccine may be given between 4 to 12 weeks following the first dose. The clinical risk priority order for deployment of the vaccines remains unchanged and applies to both vaccines. Both are very effective vaccines.
The 4 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. This will maximise the number of people getting vaccine and therefore receiving protection in the next 12 weeks.
Based on JCVI’s expert advice, it is our joint clinical advice that delivery plans should prioritise delivering first vaccine doses to as many people on the JCVI Phase 1 priority list in the shortest possible timeframe. This will allow the administration of second doses to be completed over the longer timeframes in line with conditions set out by the independent regulator, the MHRA and advice from the JCVI. This will maximise the impact of the vaccine programme in its primary aims of reducing mortality and hospitalisations and protecting the NHS and equivalent health services.
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 should be 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. The UK Chief Medical Officers agree with this advice.
