Researchers identify mutated gene linked to rare blood clots after adenovirus COVID vaccines

A New England Journal of Medicine study reports a mutated autoantibody gene as the mechanism behind vaccine-induced immune thrombocytopenia and thrombosis (VITT) after adenovirus-based COVID-19 vaccination, and researchers say changing the adenovirus protein in vaccines could prevent the disorder while preserving efficacy.

Scientists report a study published in the New England Journal of Medicine identifying a mutated autoantibody gene as the mechanism behind rare cases of vaccine-induced immune thrombocytopenia and thrombosis (VITT) after adenovirus-based COVID-19 vaccination. Researchers from Australia, Canada and Europe used mass spectroscopy and molecular analysis to investigate cases that appeared during the pandemic peak in 2021. The work seeks to explain why a small number of people developed VITT after receiving adenovirus vector vaccines or after adenovirus infection. The study also notes implications for vaccine design and safety. Key findings: - The study identified a mutated autoantibody gene reported as the mechanism driving VITT in the examined cases. - Researchers reported that altering the adenovirus protein used in vaccines could avert the disorder while preserving vaccine efficacy. - VITT occurred at an approximate rate of one in 200,000 after receipt of the Oxford-AstraZeneca vaccine in Europe and Australia or the Johnson & Johnson vaccine in the United States, and is characterized by simultaneous clotting and low platelet counts. Summary: Researchers said the discovery explains a likely biological mechanism for the rare VITT cases linked to adenovirus-based COVID-19 vaccines and could inform changes in vaccine design. Further research and any specific vaccine design actions were not detailed and are undetermined at this time.