FOI release

Lymphopenia following exposure to Comirnaty

Some or all of the information requested was not provided because we determined that the cost to do so would exceed the appropriate limit.

Case reference FOI2025/01325

Received 23 December 2025

Published 5 February 2026

Request

Dear Medicines and Healthcare Products Regulatory Agency, please provide me with reports of lymphopenia by duration after exposure to COVID-19 mRNA vaccine PrifzerBioNTech Comirnaty from licensing in 2021 to the end of 2024. We know you hold the data for a subset of 216 participants of registration trial BNT162b1 and the dataset includes lymphocyte count reported by dose, age (old or young), and assessment date. To facilitate your work the relevant clinical study report file is 125742 S1 M5 5351 Bnt162 01 Interim3 Lab Measurements (1) We would like to see your follow up of this important issue, augmented by the Yellow Card Reports show.

Response

See attached

Documents

• FOI2025_01325 (redacted).pdf (988.4 KB)

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