A pilot randomized study to assess immunogenicity, reactogenicity, safety and tolerability of two human papillomavirus vaccines administered intramuscularly and intradermally to females aged 18-26 years

Intradermal administration of human papillomavirus (HPV) vaccines could be dose-sparing and cost-saving. This pilot randomized study assessed Cervarix® and Gardasil® administered either intramuscularly or intradermally, in different doses (full-dose or reduced to 20%) by different methods (needle and syringe or PharmaJet needle-free jet injection device). Following an initial reactogenicity study of 10 male subjects, sexually naïve women aged 18-26 years were randomized to the eight study groups to receive vaccine at 0, 2 and 6 months. 42 female subjects were enrolled and complete data were available for 40 subjects. Intradermal administration of either vaccine raised no safety concerns but was more reactogenic than intramuscular administration, although still tolerable. All subjects demonstrated a seroconversion (titre ≥ 1:320) by Day 95. Further evaluation of intradermal HPV vaccination and its potential for cost reduction in resource poor settings is warranted.