The standard intramuscular tozinameran is widely used as a COVID-19 vaccine booster dose, although the fractionated-dose intradermal route of the vaccine has emerged as a dose-sparing and cost-effective alternative. However, before implementing the intradermal vaccine in patients with immune-mediated dermatologic diseases, its immunogenicity should be confirmed, as many of them use long-term immunosuppressive medications, which may alter their immune responses to the vaccine. This prospective open-labelled single-blinded randomised-controlled parallel-grouped non-inferiority trial aims to determine non-inferiority in the immunogenicity of fractionated-dose intradermal tozinameran in comparison with the standard intramuscular tozinameran as the fourth COVID-19 vaccine dose in patients with immune-mediated dermatologic diseases and compare vaccine-related adverse effects between the two.
This is a randomised controlled trial conducted to prove that the immunological performance of intradermal tozinameran (i.e., Pfizer-BioNTech COVID-19 vaccine) is no worse than the standard intramuscular route in patients with immune-mediated dermatologic diseases. The side effects profile and disease activity post-vaccination will also be assessed.