Dengue Vaccines
A boon for the menace in the tropics?
The Butantan Dengue vaccine is a live attenuated vaccine and the third in a series of vaccines which has shown some promise in successfully preventing symptomatic Dengue infection. Dengvaxia (Sanofi) which is a Yellow fever-derived chimeric vaccine and Qdenga (Takeda) which contains live attenuated DENV2 plus DENV2 chimeras of other serotypes are the predecessors. The antibody dependent enhancement and direct pathogenicity of the Non-structural protein (NS1) posed challenges to successful development of a Dengue vaccine ever since its inception about 50 years ago.
The non-neutralizing IgG-bound Dengue virus bind to Fc-gamma-receptors on effector cells, the outcome of which depends on the balance of activating to inhibitory Fc-gamma signaling.1 The three-dosed Dengvaxia led to severe Dengue in previously seronegative persons and hence its use was limited to areas with high seroprevalence or persons with documented seropositive status.2
Butantan Dengue vaccine demonstrated more than 79% efficacy through 2 years of follow-up with a single dose of the vaccine regardless of the serostatus at baseline. Read the full article by clicking the link.
Thulin NK, Brewer RC, Sherwood R, Bournazos S, Edwards KG, Ramadoss NS, Taubenberger JK, Memoli M, Gentles AJ, Jagannathan P, Zhang S, Libraty DH, Wang TT. Maternal Anti-Dengue IgG Fucosylation Predicts Susceptibility to Dengue Disease in Infants. Cell Rep. 2020 May 12;31(6):107642.
Sridhar S, Luedtke A, Langevin E, et al. Effect of dengue serostatus on dengue vaccine safety and efficacy. N Engl J Med 2018;379:327-340.