Anti-Schistosomiasis Sm14-vaccine in Senegal

Previous clinical trials have already demonstrated the safety of the candidate vaccine in adults as well as in children, in good health or infected with schistosomiasis. Regarding the induced immune response, more than 80% of vaccinated subjects were seroconverted after three vaccine injections. The induced immune response was substantial but transient. In order to obtain a more lasting immune response, the investigator will experiment with a new vaccination schedule (2 injections 1-month interval and the 3rd injection 5 months after the first dose), versus the vaccine schedule initially used (3 injections at 1-month interval).This trial will be the last phase 2 before testing the efficacy of the rSm14 vaccine candidate.

Inclusion Criteria:Man living in villages in the Saint Louis region where schistosomiasis is endemic.Having an infectious history of schistosomiasis.Adult between 18 and 49 years old at the time of the first injection.Have received pre-treatment with PZQ four to eight weeks before inclusion.Consent signed by the volunteer after information.Satisfactory state of health, confirmed on clinical examination and following biological assessment (Vpi / W-1).Available for the duration of the trial.To be negative to the Covid-19 antigenic testExclusion Criteria (Non inclusion criteria) :Subject not meeting one of the inclusion criteria.Participation to a previous anti-schistosomiasis vaccine clinical trial.Participation in another ongoing clinical researchCurrent or previous chronic administration (defined as more than 14 days) of immunosuppressive drugs or other immune modulating drugs.Known hypersensitivity to any component present in the Sm14 vaccine, or to any given vaccine, and / or history of allergic disease.Acute illness at the time of inclusion.Other conditions which, according to the PI, can potentially represent a danger to the subject to be included.