Vascular thrombosis after single dose Ad26.COV2.S vaccine in healthcare workers in South Africa : open label, single arm, phase 3B study (Sisonke study)

© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ..

Objective: To assess the rates of vascular thrombotic adverse events in the first 35 days after one dose of the Ad26.COV2.S vaccine (Janssen/Johnson & Johnson) in healthcare workers in South Africa and to compare these rates with those observed in the general population.

Design: Open label, single arm, phase 3B study.

Setting: Sisonke study, South Africa, 17 February to 15 June 2021.

Participants: The Sisonke cohort of 477 234 healthcare workers, aged ≥18 years, who received one dose of the Ad26.COV2.S vaccine.

Main outcome measures: Observed rates of venous arterial thromboembolism and vaccine induced immune thrombocytopenia and thrombosis in individuals who were vaccinated, compared with expected rates, based on age and sex specific background rates from the Clinical Practice Research Datalink GOLD database (database of longitudinal routinely collected electronic health records from UK primary care practices using Vision general practice patient management software).

Results: Most of the study participants were women (74.9%) and median age was 42 years (interquartile range 33-51). Twenty nine (30.6 per 100 000 person years, 95% confidence interval 20.5 to 44.0) vascular thrombotic events occurred at a median of 14 days (7-29) after vaccination. Of these 29 participants, 93.1% were women, median age 46 (37-55) years, and 51.7% had comorbidities. The observed to expected ratios for cerebral venous sinus thrombosis with thrombocytopenia and pulmonary embolism with thrombocytopenia were 10.6 (95% confidence interval 0.3 to 58.8) and 1.2 (0.1 to 6.5), respectively. Because of the small number of adverse events and wide confidence intervals, no conclusions were drawn between these estimates and the expected incidence rates in the population.

Conclusions: Vaccine induced immune thrombocytopenia and thrombosis after one dose of the Ad26.COV2.S vaccine was found in only a few patients in this South African population of healthcare workers. These findings are reassuring if considered in terms of the beneficial effects of vaccination against covid-19 disease. These data support the continued use of this vaccine, but surveillance is recommended to identify other incidences of venous and arterial thromboembolism and to improve confidence in the data estimates.

Trial registration: ClinicalTrials.gov NCT04838795.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:2

Enthalten in:

BMJ medicine - 2(2023), 1 vom: 12., Seite e000302

Sprache:

Englisch

Beteiligte Personen:

Jacobson, Barry Frank [VerfasserIn]
Schapkaitz, Elise [VerfasserIn]
Takalani, Azwi [VerfasserIn]
Rowji, Pradeep Frank [VerfasserIn]
Louw, Vernon [VerfasserIn]
Opie, Jessica [VerfasserIn]
Bekker, Linda Gail [VerfasserIn]
Garrett, Nigel [VerfasserIn]
Goga, Ameena [VerfasserIn]
Reddy, Tarylee [VerfasserIn]
Zuma, Nonhlanhla Yende [VerfasserIn]
Sanne, Ian [VerfasserIn]
Seocharan, Ishen [VerfasserIn]
Peter, Jonny [VerfasserIn]
Robinson, Michelle [VerfasserIn]
Collie, Shirley [VerfasserIn]
Khan, Amber [VerfasserIn]
Takuva, Simbarashe [VerfasserIn]
Gray, Glenda [VerfasserIn]

Links:

Volltext

Themen:

COVID-19
Clinical trial
Hematologic diseases
Journal Article
Thromboembolism

Anmerkungen:

Date Revised 08.05.2023

published: Electronic-eCollection

ClinicalTrials.gov: NCT04838795

Citation Status PubMed-not-MEDLINE

doi:

10.1136/bmjmed-2022-000302

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM355672871