This is a phase II step-wise, randomized, multicenter, double-blind and controlled clinical trial to evaluate the safety and immunogenicity of an attenuated tetravalent lyophilized dengue vaccine manufactured by Butantan Institute. A total of 300 volunteers will be recruited including men and no pregnant/breastfeeding women between 18 and 59 years of age complete, with and without previous exposure to dengue that will be randomized into Step A and Step B. Step A will include 50 volunteers with no previous exposure and they will be randomly assigned to receive one dose of either the lyophilized formulation (Butantan), or the liquid formulation (TetraVax-DV Vaccine - Admixture TV003 developed by NIH/NIAID and produced and formulated at Butantan according the NIH-Protocol), or the placebo. A second dose will be administered six months after the first vaccination as part of an exploratory assessment. Step B will include 250 participants(50 without previous exposure to dengue,and 200 with previous exposure to dengue) who will be randomly assigned to receive one dose of either the lyophilized formulation (Butantan),or the placebo. All participants included in both steps will be followed by a period of five years after their inclusion in the study. The vaccines will be administered at dose of 1000 PFU (for each of the vaccine viruses),and both vaccines and the placebo will be administered subcutaneously.
This is a phase II step-wise, randomized, multicenter, double-blind and controlled clinical trial to evaluate the safety and immunogenicity of a attenuated tetravalent lyophilized dengue vaccine manufactured by Butantan Institute. Three Clinical Sites at University of Sao Paulo - Brazil will participate in the study. A total of 300 volunteers will be recruited and divided into two steps: Step A (with no previous exposure to dengue) and Step B (with and without previous exposure to dengue). In step A the participants will be assigned to receive either the lyophilized vaccine, or the liquid vaccine(developed at NIH and produced and formulated at Butantan according to the NIH-Protocol), or the placebo. In Step B participants will be assigned to receive either the lyophilized vaccine, or the placebo. Both vaccine formulations (lyophilized and liquid) are composed of the same attenuated viruses: rDEN1∆30, rDEN2/4∆30(ME), rDEN3∆30/31, and rDEN4∆30. At the end of the study, 20 volunteers will have received the liquid formulation (NIH), 210 the lyophilized formulation (Butantan), and 70 will have received the placebo. All participants included in both steps will be followed by a period of five years after their inclusion in the study. The study hypothesis is that the investigational lyophilized dengue vaccine manufactured by Butantan Institute is safe and confers balanced immune response, after one dose of 1000PFU, to all for vaccine viruses.