Question to the Department of Health and Social Care:

To ask the Secretary of State for Health and Social Care, when the Medicines and Healthcare products Regulatory Agency first received clinical evidence on immune thrombocytopenia as a possible adverse effect of a covid-19 vaccination.

Immune thrombocytopenia (ITP) is an adverse event of special interest for COVID-19 vaccines and was under enhanced monitoring from the start of the United Kingdom immunisation programme. The Medicines and Healthcare products Regulatory Agency (MHRA) first received a report of suspected immune thrombocytopenia following COVID-19 vaccination in late December 2020. No cases of ITP where reported from the clinical trials for the COVID-19 vaccines used in the UK immunisation programme from December 2020.

A series of MHRA reviews of ITP and thrombocytopenia were presented to the Commission on Human Medicine (CHM)’s Expert Working Group on COVID-19 vaccine Benefit Risk from February 2021 onwards. Warnings about a very rare risk of thrombosis and thrombocytopenia were added to the product information for the AstraZeneca vaccine in early April 2021. A warning about a very rare risk of thrombocytopenia without thrombosis, including ITP, has also since been added to the AstraZeneca vaccine product information. The CHM advised that the benefits of the vaccine continue to outweigh any known risks.