Safety and immunogenicity of a tetravalent live-attenuated dengue vaccine in flavivirus naive children.
A live-attenuated tetravalent dengue virus (DENV) vaccine candidate has been well tolerated and immunogenic in healthy, US flavivirus naive adult volunteers. We conducted a pilot, safety, and immunogenicity trial of the vaccine candidate in healthy Thai children (6-7 years of age) to prepare for its eventual evaluation in Thai infants. In an uncontrolled, open clinical trial, the investigational vaccine was administered on study Days 0 and 180 to seven volunteers residing in Bangkok without neutralizing antibodies to DENV1-4 or to Japanese encephalitis virus (JEV). Clinical and laboratory safety assessments were completed during the 30 days after each vaccine dose, and immunogenicity was determined at Day 30. In this study, the vaccine was well tolerated with no serious adverse events or alert laboratory values. One volunteer experienced fever (38.2 degrees C, < 2 days) and associated DENV4 vaccine viremia 7 days after Dose 2. One month after Dose 2, six volunteers in the per-protocol analysis exhibited a tetravalent neutralizing antibody response with DENV1-4 geometric mean titers of 55, 475, 350, and 171, respectively. Ten weeks (~75 days) after Dose 2, five of the six volunteers continued to exhibit a tetravalent neutralizing antibody profile; one volunteer's DENV4 PRNT50 titer fell below the assay cut-off (29 --> < 10); (clinicaltrials.gov NCT00384670).
Simasathien
Sriluck
S
Department of Pediatrics, Phramongkutklao Hospital, Bangkok, Thailand. ssriluck@hotmail.com
Thomas
Stephen J
SJ
Watanaveeradej
Veerachai
V
Nisalak
Ananda
A
Barberousse
Célia
C
Innis
Bruce L
BL
Sun
Wellington
W
Putnak
J Robert
JR
Eckels
Kenneth H
KH
Hutagalung
Yanee
Y
Gibbons
Robert V
RV
Zhang
Chunlin
C
De La Barrera
Rafael
R
Jarman
Richard G
RG
Chawachalasai
Wipa
W
Mammen
Mammen P
MP
D002648:Child; D003715:Dengue / Q000276:immunology*; D053059:Dengue Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D003716:Dengue Virus / Q000145:classification / Q000302:isolation & purification; D004334:Drug Administration Schedule; D005260:Female; D005334:Fever; D006801:Humans; D008297:Male; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D014766:Viremia
D053059:Dengue Vaccines; D014613:Vaccines, Attenuated