Will women ever be able to get vaccinated against chlamydia, the common sexually transmitted disease? Preliminary work on a vaccine has yielded encouraging results, although the road is still long, according to a study released Tuesday.
A vaccine "capable of provoking an immune response"
Published in The Lancet Infectious Diseases , this work shows that a vaccine being developed is "safe and capable of eliciting an immune response." But even if these elements are "encouraging", they are still at a very preliminary stage: further research will indeed be needed "to determine whether the immune response provoked effectively protects against chlamydia infection", according to the study.
This is the first vaccine against this bacterial infection to be tested in a clinical trial. He is in Phase 1, the most preliminary stage.
131 million people affected
Every year, 131 million people worldwide become infected with chlamydia, according to estimates by the World Health Organization (WHO). These estimates may be underestimated because some 70% of infected women have no symptoms and are unaware that they have contracted this sexually transmitted infection (STI).
It is more common among women aged 18 to 25 than men of the same age. In women, it can lead to serious complications, including pelvic inflammatory diseases, ectopic pregnancies and even infertility. In addition, it increases the risk of contracting other STIs, such as gonorrhea or HIV infection, the AIDS virus.
"The need for a vaccine is real"
Infection with chlamydia bacteria can be cured with antibiotic therapy. But "given the impact of this epidemic on women's health, on reproductive health, on the health of children in case of transmission (...), the need for a vaccine is real," said one of the authors of the study, Professor Peter Andersen, of the Danish research institute Statens Serum Institute.
The researchers conducted the study on 35 women who had not been infected with chlamydia, using two different formulations of the vaccine. Fifteen women received one of these formulations, administered five times, by bites in the arm and sprays in the nose, fifteen others received the second also in five times, and the last five received a placebo. Both formulations of the vaccine elicited an immune response, i.e. antibody production, in all the women tested.
However, the performance of the first formulation was better because it allowed to produce more antibodies. It was therefore she who was chosen for further research. "Although many more years of research are needed, we plan to move to the next phase, the Phase 2 clinical study," said one of the scientists, Helene B. Juel.