Late Administration of Remdesivir, Guided by Antigen Test Results, in a Patient Experiencing Difficulty Weaning From the Ventilator Due to Severe COVID-19 Pneumonia

A 70-year-old woman with a history of malignant lymphoma (in remission) and systemic sclerosis required mechanical ventilation because of severe coronavirus disease 2019 pneumonia. Despite the administration of broad-spectrum antibiotics, antifungal agents, and corticosteroids, respiratory failure persisted, and a tracheostomy was performed on hospital day 17. Ventilator weaning remained difficult up to hospital day 30 and persistent detection of the severe acute respiratory syndrome coronavirus 2 antigen prompted initiation of remdesivir. Treatment was continued until the antigen became undetectable, after which successful ventilator weaning was achieved. This case suggests an association between prolonged antigen presence and sustained respiratory failure.