Evaluation of 5.1-[NANP]19, a recombinant Plasmodium falciparum vaccine candidate, in adults.
In a randomized single-blind study, 13 healthy adult volunteers were subcutaneously immunized with 2 or 3 single 50 or 400 micrograms doses of a Plasmodium falciparum recombinant vaccine candidate designated 5.1-[NANP]19. The vaccine caused transitory reactions at the injection site. Eight (62%) volunteers had a greater than or equal to 4-fold increase of antibody titer against sporozoites in immunofluorescence assay, all 13 seroconverted in IgG enzyme-linked immunosorbent assay against [NANP]50 antigen, and in 6 (46%) a lymphocyte proliferation index greater than or equal to 3 against 5.1 antigen was observed. Seven volunteers were challenged with mosquitoes infected with P. falciparum. All developed detectable parasitemia after 7 to 12 days and all received drug therapy within 24 hours. One volunteer with a cellular response to 5.1 had two negative in vitro parasite cultures before treatment, despite overt parasitemia. He was the only challenged volunteer who remained free of malaria symptoms.
Stürchler
D
D
F Hoffmann-La Roche Ltd, Basel, Switzerland.
Just
M
M
Berger
R
R
Reber-Liske
R
R
Matile
H
H
Etlinger
H
H
Takacs
B
B
Rudin
C
C
Fernex
M
M
D000328:Adult; D000818:Animals; D000917:Antibody Formation; D000953:Antigens, Protozoan / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007279:Injections, Subcutaneous; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D010963:Plasmodium falciparum / Q000276:immunology*; D015800:Protozoan Proteins; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
D000953:Antigens, Protozoan; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; C063362:QF116 antigen, Plasmodium falciparum; D014614:Vaccines, Synthetic; C041595:circumsporozoite protein, Protozoan