A field trial to assess a blood-stage malaria vaccine.
N Engl J Med
; 365(11): 1004-13, 2011 Sep 15.
Article
em En
| MEDLINE
| ID: mdl-21916638
ABSTRACT
BACKGROUND:
Blood-stage malaria vaccines are intended to prevent clinical disease. The malaria vaccine FMP2.1/AS02(A), a recombinant protein based on apical membrane antigen 1 (AMA1) from the 3D7 strain of Plasmodium falciparum, has previously been shown to have immunogenicity and acceptable safety in Malian adults and children.METHODS:
In a double-blind, randomized trial, we immunized 400 Malian children with either the malaria vaccine or a control (rabies) vaccine and followed them for 6 months. The primary end point was clinical malaria, defined as fever and at least 2500 parasites per cubic millimeter of blood. A secondary end point was clinical malaria caused by parasites with the AMA1 DNA sequence found in the vaccine strain.RESULTS:
The cumulative incidence of the primary end point was 48.4% in the malaria-vaccine group and 54.4% in the control group; efficacy against the primary end point was 17.4% (hazard ratio for the primary end point, 0.83; 95% confidence interval [CI], 0.63 to 1.09; P=0.18). Efficacy against the first and subsequent episodes of clinical malaria, as defined on the basis of various parasite-density thresholds, was approximately 20%. Efficacy against clinical malaria caused by parasites with AMA1 corresponding to that of the vaccine strain was 64.3% (hazard ratio, 0.36; 95% CI, 0.08 to 0.86; P=0.03). Local reactions and fever after vaccination were more frequent with the malaria vaccine.CONCLUSIONS:
On the basis of the primary end point, the malaria vaccine did not provide significant protection against clinical malaria, but on the basis of secondary results, it may have strain-specific efficacy. If this finding is confirmed, AMA1 might be useful in a multicomponent malaria vaccine. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT00460525.).
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Anticorpos Antiprotozoários
/
Malária Falciparum
/
Vacinas Antimaláricas
Tipo de estudo:
Clinical_trials
/
Prognostic_studies
Limite:
Child, preschool
/
Female
/
Humans
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Male
Idioma:
En
Revista:
N Engl J Med
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Mali