Authors: Martha Powell, Future Science Group
The first chlamydia vaccine to reach Phase I clinical trials has been observed to be safe and immunogenic. The novel vaccine candidate, termed CTH522, is based on the major outer membrane protein of the Chlamydia trachomatis bacterium.
The study, published recently in The Lancet Infectious Diseases, was a randomized controlled trial enrolling 35 healthy women to assess the chlamydia vaccine. Author, Peter Andersen, from Statens Serum Institut (Copenhagen, Denmark) commented on the need for a vaccine: “Given the impact of the chlamydia epidemic on women’s health, reproductive health, infant health through vertical transmission and increased susceptibility to other sexually transmitted diseases, a global unmet medical need exists for a vaccine against genital chlamydia.”
The researchers tested two formulations of the chlamydia vaccine, one with CAF01 liposome designed to aid cellular immunity, and one with aluminium hydroxide, known to aid antibody production. The participants were randomly assigned to three groups: one for each CTH522 formulation and one to a placebo vaccine, with the vaccine administered via three intramuscular injection on day zero, day 28 and day 112, and two intranasal boosters on day 126 and 140.