PB0086 Prospective Assessment of Thrombomodulin Resistance in Oncological Patients and Healthy Subjects Following Vaccination Against Sars-Cov-2 with the mRNAVaccine. The Roadmap-COVID-19-Vaccin Study

Background: Traditionally, the administration of intramuscular vaccination has been avoided in patients with congenital coagulopathies due to its possible deleterious effects, including large hematomas, contractures or fibrosis.However, vaccination against SARS-CoV-2 received approval from regulatory agencies only for intramuscular administration, since its efficacy by other routes has not been studied, so its administration was generalized by this route in this group of patients.Aims: The objective is to evaluate the possible adverse effects secondary to vaccination against COVID-19 in patients diagnosed with congenital coagulopathies in a single center.Methods: Retrospective, analytical and single-center study documenting the adverse effects of vaccination against COVID-19 in a population diagnosed with congenital coagulopathies in a rural center in Spain.Clinical and epidemiological results were collected.Results: Twenty-six patients (61.5% male population) with a median age of 24 years (range 3-79 years) were evaluated.The most frequent congenital coagulopathies were deficiency of factor VII (34.6%),VIII (19.2%) and XI (19.2%).11.5% received prophylaxis.20% of the sample was infected during the first wave of the pandemic ( pre-vaccination) without the need for hospital admission.The entire sample received vaccination in the complete scheme (3 doses, 57.7% were administered from the Pfizer-Bi brand, the difference from the Moderna-Rec brand) without evidence of significant hemorrhagic or thrombotic complications, presenting the entire sample of humoral immune response.No patient in the sample has required hospital admission secondary to severe COVID-19.Conclusion(s): After completing the vaccination schedule against SARS-CoV-2, it can be inferred that the intramuscular administration of this vaccine does not produce significant hemorrhagic adverse events, being the route of preference at present.