Preliminary observations on the efficacy of a recombinant multistage Plasmodium falciparum vaccine in Aotus nancymai monkeys.
A vaccine trial was conducted to determine the efficacy of a multicomponent candidate vaccine, FALVAC-1, against Plasmodium falciparum in Aotus nancymai monkeys. After two immunizations, animals were challenged intravenously with parasites of the Vietnam Oak Knoll (FVO) strain of P. falciparum. The primary outcome was to determine the protective response of the monkeys to immunization with the FALVAC-1 antigen produced in baculovirus when combined with different adjuvants (alum, QS-21, ASO2a, CRL1005/oil, and CRL1005/saline) as compared with FALVAC-1 with FCA/FIA and antigen alone. When compared with the monkeys immunized with FALVAC-1 alone, FALVAC-1 with FCA/FIA reduced the mean parasite count (to Day 11), reduced the mean accumulated parasitemia (through Day 11), and extended the number of days to treatment. None of the other 5 antigen-adjuvant combinations were able to provide discernable levels of protection based on log(parasitemia) and log(cumulative parasitemia) to Day 11.
Collins
William E
WE
Division of Parasitic Diseases, Centers for Disease Control and Prevention, Public Health Service, U. S. Department of Health and Human Services, Atlanta, Georgia 30341, USA. wec1@cdc.gov
Galland
G Gale
GG
Barnwell
John W
JW
Udhayakumar
Venkatachalam
V
Sullivan
JoAnn S
JS
Nace
Douglas
D
Tongren
Jon Eric
JE
Williams
Tyrone
T
Roberts
Jacquelin
J
Shi
Ya Ping
YP
Lal
Altaf A
AA
D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000534:Alum Compounds / Q000008:administration & dosage; D000818:Animals; D016645:Aotidae; D004195:Disease Models, Animal; D004338:Drug Combinations; D005260:Female; D005620:Freund's Adjuvant / Q000008:administration & dosage / Q000276:immunology; D006400:Hematocrit; D007115:Immunization Schedule; D008050:Lipid A / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000276:immunology; D017780:Malaria Vaccines / Q000008:administration & dosage* / Q000009:adverse effects / Q000235:genetics / Q000276:immunology; D016778:Malaria, Falciparum / Q000517:prevention & control*; D008297:Male; D010963:Plasmodium falciparum / Q000276:immunology* / Q000472:pathogenicity; D011108:Polymers / Q000008:administration & dosage; D012503:Saponins / Q000008:administration & dosage / Q000276:immunology; D016896:Treatment Outcome; D014614:Vaccines, Synthetic / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology
C501939:ASO2A adjuvant; D000276:Adjuvants, Immunologic; D000534:Alum Compounds; C113154:CRL 1005; D004338:Drug Combinations; D008050:Lipid A; D017780:Malaria Vaccines; D011108:Polymers; D012503:Saponins; D014614:Vaccines, Synthetic; C041524:aluminum sulfate; C078785:saponin QA-21V1; D005620:Freund's Adjuvant