Safety and immunogenicity of a recombinant nonglycosylated erythrocyte binding antigen 175 Region II malaria vaccine in healthy adults living in an area where malaria is not endemic.
Erythrocyte binding antigen region II (EBA-175) is a conserved antigen of Plasmodium falciparum that is involved in binding of the parasite to the host's erythrocytes. We evaluated the safety and immunogenicity of a recombinant EBA-175 vaccine with aluminum phosphate adjuvant in healthy young adults living in the United States. Eighteen subjects/group received ascending doses (5, 20, 80, or 160 μg) of the vaccine at 0, 1, and 6 months; 8 subjects received placebo. Most of the injection site and systemic reactions were mild to moderate in intensity. After 2 or 3 doses of the vaccine at any concentration, antibody levels measured by enzyme-linked immunosorbent assay were significantly higher than those for the placebo group. Sera from subjects who received 3 doses of the vaccine at any concentration inhibited the growth of erythrocyte-stage P. falciparum at low levels compared to sera from placebo recipients or preimmune sera. In conclusion, the EBA-175 vaccine with adjuvant was safe and immunogenic in malaria-naïve subjects.
El Sahly
H M
HM
Departments of Molecular Virology and Microbiology and Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA. hanae@bcm.edu
Patel
S M
SM
Atmar
R L
RL
Lanford
T A
TA
Dube
T
T
Thompson
D
D
Sim
B K L
BK
Long
C
C
Keitel
W A
WA
D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000293:Adolescent; D000328:Adult; D017607:Aluminum Compounds / Q000008:administration & dosage; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006805:Human Experimentation; D006801:Humans; D007117:Immunization, Secondary / Q000379:methods; D017780:Malaria Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D016778:Malaria, Falciparum / Q000517:prevention & control*; D008297:Male; D010710:Phosphates / Q000008:administration & dosage; D010919:Placebos / Q000008:administration & dosage; D010963:Plasmodium falciparum / Q000254:growth & development / Q000276:immunology; D015800:Protozoan Proteins / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D014481:United States; D014611:Vaccination / Q000379:methods; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D055815:Young Adult
D000276:Adjuvants, Immunologic; D017607:Aluminum Compounds; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D017780:Malaria Vaccines; D010710:Phosphates; D010919:Placebos; D015800:Protozoan Proteins; D014614:Vaccines, Synthetic; C065668:erythrocyte-binding antigen 175, Plasmodium; C012714:aluminum phosphate