Immunogenicity and Protective Efficacy of Radiation-Attenuated and Chemo-Attenuated PfSPZ Vaccines in Equatoguinean Adults
| Autor: | Claudia Daubenberger, Dianna Hergott, Said Jongo, Thomas L. Richie, Peter F. Billingsley, Maximillian Mpina, Jose Raso Bijeri, Ally Olotu, Tooba Murshedkar, Elizabeth Saverino, Linda Gondwe, Salome Hosch, Marcel Tanner, Eric R. James, Ali Hamad, Elizabeth Nyakarungu, Carl Maas, Ali Mtoro, Julian Sax, J. Luis Segura, Stephen L. Hoffman, Beltrán Ekua Ntutumu Pasialo, Natasha Kc, Anneth-Mwasi Tumbo, Wonder P. Phiri, Stephen R. Manock, Christopher Schwabe, Martin Eka Ondo Mangue, Mitoha Ondo’o Ayekaba, Mwajuma Chemba, Anna Deal, Vicente Urbano, Kamaka R Kassim, Genaro Nsue Nguema, Salim Abdulla, Salomon Nguema Owono, Yonas Abebe, Thomas C. Stabler, Matilde Riloha Rivas, Carlos Cortes Falla, Guillermo A. García, B. Kim Lee Sim, L. W. Preston Church, Tobias Schindler |
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| Rok vydání: | 2021 |
| Předmět: |
Adult
Male Cellular immunity Adolescent Plasmodium falciparum 030231 tropical medicine Antibodies Protozoan Parasitemia Vaccines Attenuated Antimalarials Young Adult 03 medical and health sciences Immunogenicity Vaccine 0302 clinical medicine Double-Blind Method Chloroquine Virology Malaria Vaccines Animals Humans Medicine 030212 general & internal medicine Malaria Falciparum Child Aged biology business.industry Immunogenicity Infant Articles Middle Aged Vaccine efficacy medicine.disease biology.organism_classification PfSPZ vaccine Infectious Diseases Child Preschool Equatorial Guinea Immunology Chemoprophylaxis Female Immunization Parasitology business medicine.drug |
| Zdroj: | The American Journal of Tropical Medicine and Hygiene |
| ISSN: | 1476-1645 0002-9637 |
| Popis: | Plasmodium falciparum sporozoite (PfSPZ) Vaccine (radiation-attenuated, aseptic, purified, cryopreserved PfSPZ) and PfSPZ-CVac (infectious, aseptic, purified, cryopreserved PfSPZ administered to subjects taking weekly chloroquine chemoprophylaxis) have shown vaccine efficacies (VEs) of 100% against homologous controlled human malaria infection (CHMI) in nonimmune adults. Plasmodium falciparum sporozoite-CVac has never been assessed against CHMI in African vaccinees. We assessed the safety, immunogenicity, and VE against homologous CHMI of three doses of 2.7 × 106 PfSPZ of PfSPZ Vaccine at 8-week intervals and three doses of 1.0 × 105 PfSPZ of PfSPZ-CVac at 4-week intervals with each arm randomized, double-blind, placebo-controlled, and conducted in parallel. There were no differences in solicited adverse events between vaccinees and normal saline controls, or between PfSPZ Vaccine and PfSPZ-CVac recipients during the 6 days after administration of investigational product. However, from days 7–13, PfSPZ-CVac recipients had significantly more AEs, probably because of Pf parasitemia. Antibody responses were 2.9 times higher in PfSPZ Vaccine recipients than PfSPZ-CVac recipients at time of CHMI. Vaccine efficacy at a median of 14 weeks after last PfSPZ-CVac dose was 55% (8 of 13, P = 0.051) and at a median of 15 weeks after last PfSPZ Vaccine dose was 27% (5 of 15, P = 0.32). The higher VE in PfSPZ-CVac recipients of 55% with a 27-fold lower dose was likely a result of later stage parasite maturation in the liver, leading to induction of cellular immunity against a greater quantity and broader array of antigens. |
| Databáze: | OpenAIRE |
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