FOI release

Freedom of Information request on Scrutiny of Vaccine Data (FOI 21-034)

Published 24 March 2021

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The authorisation of the Pfizer/BioNTech and the Oxford/AstraZeneca vaccines was done through an expedited rolling review. A ‘rolling review’ can be used to complete the assessment of a promising medicine or vaccine during a public health emergency in the shortest time possible. This is done as the packages of data become available from ongoing studies on a staggered basis. The temporary authorisation under Regulation 174 permits the supply of identified vaccine batches, based on the safety, quality and efficacy data submitted to MHRA. These authorisations do not constitute a marketing authorisation.

All vaccines are tested through three phases of clinical trials to ensure they meet the gold standard. Phase 1 trials are with a small group of people to make sure there are no safety concerns and determines the appropriate dosage for the best immune response. Phase 2 trials are conducted on a larger group of people to check the vaccine works consistently and that the immune response is sufficient. Phase 3 trials test the vaccines on thousands of people for scientists to assess if the vaccine is producing immunity that will prevent disease. Usually, these phases are run in sequence, but in an effort to find a safe and effective Covid-19 vaccine as quickly as possible, once safety has been ascertained through Phase 1, Phases 2 and 3 are being run in parallel. Extensive checks and balances are required at every stage of the development of a vaccine, and this is no different for a Covid-19 vaccine. No stages in the vaccine development processes were bypassed.

Information on the study conducted using the Pfizer/BioNTech vaccine and its results are available in a peer-reviewed journal, the New England Journal of Medicine. A link to this is provided below: https://www.nejm.org/doi/full/10.1056/NEJMoa2034577?query=featured_home

The approval for use of the Pfizer/BioNTech and Oxford/AstraZeneca COVID-19 vaccines in the UK followed a rigorous scientific assessment of all the available evidence of quality, safety and effectiveness by the UK regulator, the Medicines and Healthcare products Regulatory Agency (MHRA). The MHRA expert scientists and clinicians reviewed data from the laboratory pre-clinical studies, clinical trials, manufacturing and quality controls, product sampling and testing of the final vaccine, and also considered the conditions for its safe supply and distribution. The decision was made with advice from the Commission on Human Medicines (CHM), the government’s independent expert scientific advisory body. Regarding the MHRA approval of the Pfizer/BioNTech and the Oxford/AstraZeneca COVID-19 vaccines, further information (including information for physicians and recipients of the vaccine, and Public Assessment Reports [PARs] for each vaccine) are available on the MHRA website. The PARs contain useful information on the mechanism of action of the Pfizer/BioNTech and Oxford/AstraZeneca vaccines. Links to these are provided below: https://www.gov.uk/government/publications/regulatory-approval-of-pfizer-biontech-vaccine-for-covid-19
https://www.gov.uk/government/publications/regulatory-approval-of-covid-19-vaccine-astrazeneca

Further to the above, the Moderna vaccine has also recently been authorised for use. Further information on this is provided below: https://www.gov.uk/government/publications/regulatory-approval-of-covid-19-vaccine-moderna

The following Department of Health and Social Care (DHSC) webpage for the independent report ‘Optimising the COVID-19 vaccination programme for maximum short-term impact’ from the Joint Committee on Vaccination and Immunisation (JCVI) provides the rationale for the government’s implemented dosing strategy:
https://www.gov.uk/government/publications/prioritising-the-first-covid-19-vaccine-dose-jcvi-statement/optimising-the-covid-19-vaccination-programme-for-maximum-short-term-impact

Further, the scientific basis from the JCVI concerning the current evidence on efficacy after single doses of the Pfizer/BioNTech, Oxford/AstraZeneca and Moderna vaccines is provided below: https://www.cas.mhra.gov.uk/ViewandAcknowledgment/ViewAttachment.aspx?Attachment_id=103741

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