Safety and High Level Efficacy of the Combination Malaria Vaccine Regimen of RTS,S/AS01B With Chimpanzee Adenovirus 63 and Modified Vaccinia Ankara Vectored Vaccines Expressing ME-TRAP.
J Infect Dis
; 214(5): 772-81, 2016 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-27307573
ABSTRACT
BACKGROUND:
The need for a highly efficacious vaccine against Plasmodium falciparum remains pressing. In this controlled human malaria infection (CHMI) study, we assessed the safety, efficacy and immunogenicity of a schedule combining 2 distinct vaccine types in a staggered immunization regimen one inducing high-titer antibodies to circumsporozoite protein (RTS,S/AS01B) and the other inducing potent T-cell responses to thrombospondin-related adhesion protein (TRAP) by using a viral vector.METHOD:
Thirty-seven healthy malaria-naive adults were vaccinated with either a chimpanzee adenovirus 63 and modified vaccinia virus Ankara-vectored vaccine expressing a multiepitope string fused to TRAP and 3 doses of RTS,S/AS01B (group 1; n = 20) or 3 doses of RTS,S/AS01B alone (group 2; n = 17). CHMI was delivered by mosquito bites to 33 vaccinated subjects at week 12 after the first vaccination and to 6 unvaccinated controls.RESULTS:
No suspected unexpected serious adverse reactions or severe adverse events related to vaccination were reported. Protective vaccine efficacy was observed in 14 of 17 subjects (82.4%) in group 1 and 12 of 16 subjects (75%) in group 2. All control subjects received a diagnosis of blood-stage malaria parasite infection. Both vaccination regimens were immunogenic. Fourteen protected subjects underwent repeat CHMI 6 months after initial CHMI; 7 of 8 (87.5%) in group 1 and 5 of 6 (83.3%) in group 2 remained protected.CONCLUSIONS:
The high level of sterile efficacy observed in this trial is encouraging for further evaluation of combination approaches using these vaccine types. CLINICAL TRIALS REGISTRATION NCT01883609.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Portadores de Fármacos
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Proteínas de Protozoários
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Esquemas de Imunização
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Malária Falciparum
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Vacinas Antimaláricas
Tipo de estudo:
Clinical_trials
Limite:
Adolescent
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Adult
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Animals
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Infect Dis
Ano de publicação:
2016
Tipo de documento:
Article