Abstract

TETRAVALENT DENGUE VACCINE FOR THE PREVENTION OF DENGUE FEVER

Navya Mariam Koshy*, Reza Rajesh, Sharon Liza Koshy, Renuka R., Elessy Abraham

ABSTRACT

Dengue is a mosquito-borne flavivirus disease that has spread to most tropical and many subtropical areas. There is no specific therapeutics strategy for dengue fever. Prevention is currently limited to vector control measures. A dengue vaccine would therefore represent a major advance in the control of the disease. The development of vaccine for dengue fever began as early as 1929, but has been hindered first by incomplete knowledge of the disease pathogenesis, and later by the need to simultaneously create a stable immunity against all four dengue serotypes. Several vaccine candidates are in development including live attenuated, inactivated, DNA and subunit vaccines. Live attenuated vaccine candidates are the furthest along in development. Dengue vaccine development has reached a major milestone with the initiation, in 2010, of the first phase III clinical trial to investigate the Sanofi Pasteur CYD tetravalent dengue vaccine (TDV). The CYD TDV candidate is composed of four recombinant, live, attenuated vaccines (CYD-1–4) based on a yellow fever vaccine 17D (YFV 17D) backbone, each expressing the pre-membrane and envelope genes of one of the four dengue virus serotypes. The vaccine is genetically and phenotypically stable, non-hepatotropic, less neurovirulent than YFV 17D. It was seen that a three-dose vaccination regimen induces an immune response against all four serotypes in the large majority of vaccinees. Preexisting flavivirus immunity favours quicker and higher immune responses to CYD TDV, without adversely effecting clinical safety or increasing vaccine viremia.

Keywords: Dengue fever, TDV Vaccine, Flavivirus.