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.
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.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
TRIPLE
Enrollment
300
Dose 1000 PFU per virus (1,2,3,4) Route:subcutaneous
Dose 1000 PFU per virus (1,2,3,4) Route: subcutaneous
Route:subcutaneous
Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da USP
São Paulo, Brazil
Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo
São Paulo, Brazil
Safety
Frequency of solicited and unsolicited local and systemic adverse reactions up to Day 21 after vaccination.
Time frame: Up to day 21 after vaccination
Immunogenicity
Seroconversion rate for each of the four vaccine viruses defined by PRNT50 ≥1:10 for each vaccine virus serotype on Days 28, 56 or 91.
Time frame: Up to day 91 after vaccination
Safety
1. Unsolicited adverse events after Day 21 and up to Day 182 after the first vaccination; 2. Viremia for each of the four vaccine virus on Days 3, 6, 9, 12, 15 and 21 after the first vaccination of all volunteers in Step A of study and 40 volunteers with previous exposure to Dengue of Step B. For other volunteers from Step B, viremia only is measured on Day 12. 3. Cases of suspected and confirmed dengue in five years after the first vaccination;
Time frame: up to Day 182 after the first vaccination
Immunogenicity
1. Response rates of monovalent, bivalent, trivalent or tetravalent, at Day 28, 56 and 91 and annually after vaccination, as measured by PRNT50 for each one of the four vaccine viruses; 2. The difference between the geometric means, pre and post vaccination, serum level of neutralizing antibodies measured by PRNT50 for each of the four vaccine viruses evaluated until five years after the first vaccination.
Time frame: Annualy up to five years
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