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Unlabelled: The ideal dengue vaccine will provide protection against all serotypes of dengue virus and will be economical and uncomplicated in its administration. To determine the ability of a single dose of the live attenuated tetravalent dengue vaccine TV003 to induce a suitable neutralizing antibody response, a placebo-controlled clinical trial was performed in 48 healthy adults who received 2 doses of vaccine or placebo administered 12 months apart. Evaluation of safety, vaccine viremia, and neutralizing antibody response after each dose indicated that the first dose of vaccine was capable of preventing infection with the second dose, thus indicating that multiple doses are unnecessary.Clinical Trials Registration: NCT01782300. [ABSTRACT FROM AUTHOR]

The article presents a study that determines the effectiveness of dengue vaccine TV003 in protecting humans against all for dengue virus (DENV) serotypes. It offers details of the method of the study that observes 21 recipients. It outlines the result which indicates that TV003 induced complete protection against challenge with rDEN2A30 after six months of vaccination, however, the treatment should be evaluated in dengue-endemic areas.

Background. The 4 serotypes of dengue virus, DENV-1-4, are the leading cause of arboviral disease globally. The ideal dengue vaccine would provide protection against all serotypes after a single dose. Methods. Two randomized, placebo-controlled trials were performed with 168 flavivirus-naive adults to demonstrate the safety and immunogenicity of a live attenuated tetravalent dengue vaccine (TV003), compared with those of a second tetravalent vaccine with an enhanced DENV-2 component (TV005), and to evaluate the benefit of a booster dose at 6 months. Safety data, viremia, and neutralizing antibody titers were evaluated. Results. A single dose of TV005 elicited a tetravalent response in 90% of vaccinees by 3 months after vaccination and a trivalent response in 98%. Compared with TV003, the higher-dose DENV-2 component increased the observed frequency of immunogenicity to DENV-2 in the TV005 trial. Both the first and second doses were well tolerated. Neither vaccine viremia, rash, nor a significant antibody boost were observed following a second dose. Conclusions. A single subcutaneous dose of TV005 dengue vaccine is safe and induces a tetravalent antibody response at an unprecedented frequency among vaccinees. A second dose has limited benefit and appears to be unnecessary. Studies to confirm these findings and assess vaccine efficacy will now move to populations in regions where DENV transmission is endemic. [ABSTRACT FROM AUTHOR]

T lymphocyte responses to human immunodeficiency virus (HIV) type 1 Gag were measured in 9 patients by interferon-γ enzyme-linked immunospot assay at 3 time points within 12 months of infection. Patients with early recognition of HIV-1 Gag had lower subsequent HIV-1 load set points, as measured during the first 2 years of infection, compared with those of patients with undetectable Gag-specific responses (median, 4.27 vs. 5.05 log[SUB10] HIV-1 RNA copies/mL, respectively; P = .028). An inverse correlation existed between the magnitude of the Gag-specific responses and the HIV-1 load set point (r = -0.733; P = .025). Early sustained T lymphocyte responses to HIV-1 Gag may be important for the establishment of virus load set point. [ABSTRACT FROM AUTHOR]

The table of contents for the March 15, 2013 issue of "The Journal ofInfectious Diseases" is presented.

Introduction Dengue viruses are estimated to cause 100-400 million symptomatic illnesses each year, with a significant and expanding burden of severe disease and mortality in both endemic populations and travelers [...], BACKGROUND. Disease due to dengue viruses is a growing global health threat, causing 100-400 million cases annually. An ideal dengue vaccine should demonstrate durable protection against all 4 serotypes in phase III efficacy trials, however the lack of circulating serotypes may lead to incomplete efficacy data. Controlled human infection models help downselect vaccine candidates and supply critical data to supplement efficacy trials. We evaluated the efficacy of a leading live-attenuated tetravalent dengue vaccine candidate, TV005, against infection with a newly established dengue serotype 3 or an established serotype 2 challenge virus. METHODS. Two randomized, controlled clinical trials were performed. In study 1, a total of 42 participants received TV005 or placebo (n = 21 each), and 6 months later, all were challenged with dengue 2 virus (rDEN2[DELTA]30) at a dose of 103 PFU. In study 2, a total of 23 participants received TV005 and 20 received placebo, and 6 months later, all were challenged with 104 PFU dengue 3 virus (rDEN3[DELTA]30). The study participants were closely monitored for safety, viremia, and immunologic responses. Infection, measured by post-challenge viremia, and the occurrence of rash and neutropenia were the primary endpoints. Secondary endpoints included safety, immunologic, and virologic profiles following vaccination with TV005 and subsequent challenge with the rDEN2[DELTA]30 or rDEN3[DELTA]30 strain. RESULTS. TV005 was well tolerated and protected all vaccinated volunteers from viremia with DENV2 or DENV3 (none infected in either group). Placebo recipients had post-challenge viremia (100% in study 1, 85% in study 2), and all experienced rash following challenge with either serotype. CONCLUSIONS. TV005 is a leading tetravalent dengue vaccine candidate that fully protected against infection with DENV2 and DENV3 in an established controlled human infection model. TRIAL REGISTRATION. ClinicalTrials.gov NCT02317900 and NCT02873260. FUNDING. Intramural Research Program, NIH (contract HHSN272200900010C).