Evaluating Safety and Immune Response of COVID-19 Booster and Flu Vaccine Given Together or Separately in People with Weakened Immune Systems

What this Trial Is About

Researchers are evaluating ways to improve the immune response to COVID-19 booster and seasonal influenza vaccines in people living with immunocompromising conditions PLIC, such as solid organ transplant recipients, people living with HIV, inflammatory bowel disease, and systemic autoimmune rheumatic diseases. This phase II randomized controlled trial aims to determine if co-administering the influenza vaccine with the COVID-19 booster is as effective as giving them sequentially, and whether more frequent COVID-19 boosters at 3-month intervals provide better long-term immunity compared to 6-month intervals. Participants will be assigned to one of four groups receiving both COVID-19 booster and influenza vaccine on the same day with COVID-19 boosters every 3 months receiving the COVID-19 booster at baseline and influenza vaccine one month later with boosters every 3 months receiving both vaccines on the same day with boosters every 6 months or receiving the COVID-19 booster at baseline and influenza vaccine one month later with boosters every 6 months. Vaccines used follow the National Advisory Committee on Immunization recommendations for immunocompromised patients. During the study, blood samples will be collected at multiple time points up to 12 months to measure immune responses, including antibody levels and T-cell activity. Researchers will monitor clinical events, therapies, vaccine side effects, quality of life, and economic impact. The main outcome is the median neutralization capacity against SARS-CoV-2 variants at specified intervals after vaccination, helping to inform optimal vaccine scheduling for this vulnerable population.

COVID-19 Booster and IIV Schedule in Immunocompromised Hosts