Phase II Randomized Trial Comparing Two Doses of High-Dose Versus Standard-Dose Influenza Vaccine in Lung Transplant Patients 1 to 35 Months Post-Transplant

What this Trial Is About

Lung transplant recipients face a higher risk of severe influenza disease and complications compared to healthy individuals. The early period after lung transplantation is critical because immunosuppression may reduce the effectiveness of the standard influenza vaccine, yet this is when protection is most needed. This research focuses on lung transplant recipients 1 to 35 months post-transplant to evaluate better vaccination strategies to reduce influenza risks in this vulnerable group. The trial compares two doses of a high-dose quadrivalent inactivated influenza vaccine HD-QIV to two doses of a standard-dose quadrivalent inactivated influenza vaccine SD-QIV, given 28 to 42 days apart. About 270 participants will be randomized to receive either vaccine type. The study actively monitors participants during influenza season, including weekly check-ins and nasal swabs to detect influenza or COVID-19-like symptoms, with additional nasal swabs collected if symptoms arise. Participants will be assessed for immune response by measuring antibody levels 56 days after vaccination and monitored for any local or systemic side effects within 7 days post-vaccination. The study also examines immune cell markers before vaccination to explore their relationship with vaccine response. The total study duration includes enrollment over three years, with continuous influenza surveillance and safety monitoring throughout the study period.

High vs. Standard Dose Influenza Vaccine in Lung Allograft Recipients