Clinical Trial of the BioMed rTSST-1 Variant Vaccine in Healthy Adults

Toxic Shock Syndrome (TSS) is a severe condition with high morbidity and mortality from the hosts overwhelming inflammatory response and cytokine storm. Staphylococcal superantigen toxins are the main causative agents. Toxic shock syndrome toxin (TSST-1) being responsible for almost all of menstruation associated and more than 50% of all other cases. There is no specific therapy. The aim of this study is to extend the safety and tolerability of two doses of the BioMed recombinant toxic shock syndrome toxin (rTSST-1) Variant Vaccine after one to three vaccinations in healthy adults. The second aim of the study is to measure immunogenicity and persistence of antibodies which produced in response to treatment with the BioMed rTSST-1 Variant Vaccine over a period of 12 months. These antibodies are expected to be important in prevention and mitigation of the diseases. 140 healthy adults, male and female, age 18-64 years will be assigned to 7 groups comprising two doses of the vaccine or adjuvant at the Department of Clinical Pharmacology of the Medical University of Vienna. The patients will be monitored for vital signs, hematology, clinical chemistry, and antibodies against TSST-1. Immunization will be repeated 3 months after the first with the same dose and 6 months after the second immunization in the respective groups. Antibodies will be determined through monitoring TSST-1 binding antibodies as assessed through ELISA and neutralizing antibodies (exploratory endpoint) as assessed by inhibition of T cell activation (3H Thymidine incorporation; ≥ 50%).