4.5 Article

Thrombocytopenia after Ad.26.COV2.S COVID-19 vaccine: Reports to the vaccine adverse event reporting system

Journal

VACCINE
Volume 40, Issue 31, Pages 4116-4120

Publisher

ELSEVIER SCI LTD
DOI: 10.1016/j.vaccine.2022.05.078

Keywords

Thrombocytopenia; VAERS; Ad.26.COV2.S COVID-19 vaccine; Coronavirus; SARS-CoV2

Ask authors/readers for more resources

The FDA has identified an increased risk of thrombocytopenia following receipt of the Ad.26.COV2.S COVID-19 vaccine, with serious cases and deaths reported.
Background: On February 27, 2021, the Food and Drug Administration (FDA) issued an Emergency Use Authorization for Ad.26.COV2.S COVID-19 vaccine. As part of post-authorization safety surveillance, the FDA has identified a potential safety concern for thrombocytopenia following receipt of Ad.26. COV2.S COVID-19 vaccine. Methods: Reports of thrombocytopenia were identified in a passive reporting system (Vaccine Adverse Event Reporting System; VAERS) February-December 2021. Demographics, clinical characteristics, laboratory values, and relevant medical history were reviewed. The reporting rate was analyzed, including calculation of the observed-to-expected ratio based on vaccine administration data and the background rate of thrombocytopenia in the general (unvaccinated) population. Results: As of December 31, 2021, 100 reports of thrombocytopenia were identified in VAERS following vaccination with Ad.26.COV2.S. The median platelet count was 33,000 per mu L (interquartile range 8,000-86,000). Fifteen reports (15%) documented a platelet count of 5,000 per mu L or lower. The median time to onset of thrombocytopenia was 9 days (interquartile range 3-18.5), with most cases (69; 69%) beginning within 14 days after vaccination. A large majority of cases (84; 84%) were serious, including six deaths. With approximately 16,292,911 doses of Ad.26.COV2.S administered to adults in the US, the crude reporting rate was 0.61 cases of thrombocytopenia per 100,000 doses administered. The overall estimated observed-to-expected rate ratio was 2.43 (95% CI 1.97, 2.95). Conclusions: These findings suggest an increased risk of thrombocytopenia following receipt of Ad.26. COV2.S. Published by Elsevier Ltd.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.5
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available