PB0596 - Anti-SARS-CoV-2 vaccines do not induce a hypercoagulable state in healthy individuals

Monday, July 11, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

Lamya Garabet, MD, PhDC

Consultant
Østfold Hospital
Grrålum, Ostfold, Norway

Co-Author(s)

AE

Anna Eriksson

Researcher
Østfold Hospital
Grålum, Ostfold, Norway
ET

Eirik Tjønnfjord

MD
Østfold Hospital
Sarpsborg, Ostfold, Norway
MO

Magnus Kringstad Olsen

Researcher
Østfold Hospital
Sarpsborg, Ostfold, Norway
HJ

Hege Karine Jacobsen

Researcher
Østfold Hospital
Grålum, Ostfold, Norway
CT

Camilla Tøvik Jørgensen

PhD fellow
Østfold Hospital
Grålum, Ostfold, Norway
�M

Åse-Berit Mathisen

Laboratory tecknition
Østfold Hospital
Grålum, Ostfold, Norway
MM

Marie-Christine Mowinckel

Senior laboratory technician
Oslo University Hospital
Oslo, Oslo, Norway
Maria Therese Ahlen, PhD

Researcher
University Hospital of North Norway
Tromsø, Troms, Norway
IS

Ingvild Hausberg Sørvoll

Consultant
University Hospital of North Norway
Tromsø, Troms, Norway
PS

Per Morten Sandset

Professor
University of Oslo
Oslo, Oslo, Norway
Waleed Ghanima, MD

Professor
Østfold Hospital Foundation
Gralum, Ostfold, Norway

Background: Anti-SARS-CoV-2 adenoviral-vectored-DNA vaccines have been linked to a rare but serious thrombotic post-vaccine complication called the vaccine-induced immune thrombotic thrombocytopenia (VITT). VITT has raised concerns regarding the possibilities of increased thrombotic risk and/thrombocytopenia after anti-COVID-19 vaccines.

Aims: To investigate whether anti-SARS-CoV-2 vaccines can cause subclinical coagulation activation and increased thrombin generation leading to a hypercoagulable state.

Methods: The study included 567 healthcare personnel from two hospitals in Norway. Of these, 521 were recruited 11-57 days post-vaccination with the first dose of ChAdOx1-S (Vaxzevria®, AstraZeneca, UK) vaccine, and 46 were recruited prospectively prior vaccination with an mRNA vaccine, either elasomeran (Spikevax, Moderna, n=38) or tozinameran (Comirnaty, Pfize-BioNTech, n=8). In the latter group, samples were acquired before and 1-2 weeks after vaccination. In addition to pre-vaccination samples, 56 unvaccinated blood donors were recruited as controls (total n=102). Thrombin generation, D-dimer and free tissue factor pathway inhibitor antigen (free TFPI) were analyzed.

Results: None of the participants developed thrombosis/VITT or thrombocytopenia (platelet count < 100·109/L) after vaccination. There were no significant differences in D-dimer, free TFPI or the parameters of thrombin generation between the two vaccine groups and the controls (Table 1). No differences in thrombin generation or free TFPI between the ChAdOx1-S group and the mRNA group, the median D-dimer level was slightly higher in the ChAdOx1-S group, but both were within the normal range (Table 2). Thrombin generation, D-dimer and free TFPI showed no changes after mRNA vaccination compared with baseline.

Conclusion(s): Anti-COVID-19 vaccines, both ChAdOx1-S and mRNA, were not associated with significant increase in thrombin generation, D-dimer or free TFPI compared with controls. Neither significant differences were observed between ChAdOx1-S and mRNA vaccines nor changes after mRNA vaccines compared with baseline levels. Our results are reassuring in the sense that no subclinical activation in the coagulation system was observed with these vaccines.