Dose-Dependent Infectivity of Aseptic, Purified, Cryopreserved Plasmodium falciparum 7G8 Sporozoites in Malaria-Naive Adults.
2019 11 06
Journal Article
Authors:
Laurens, M.B.;
Berry, A.A.;
Travassos, M.A.;
Strauss, K.;
Adams, M.;
Shrestha, B.;
Li, T.;
Eappen, A.;
Manoj, A.;
Abebe, Y.;
Murshedkar, T.;
Gunasekera, A.;
Richie, T.L.;
Lyke, K.E.;
Plowe, C.V.;
Kennedy, J.K.;
Potter, G.E.;
Deye, G.A.;
Sim, B.K.L.;
Hoffman, S.L.
Secondary:
J Infect Dis
Volume:
220
Pagination:
1962-1966
Issue:
12
PMID:
31419294
Keywords:
Administration, Intravenous; Adult; Dose-Response Relationship, Immunologic; Female; Humans; Malaria Vaccines; Malaria, Falciparum; Male; Plasmodium falciparum; Sporozoites; Vaccination
Abstract:
Direct venous inoculation of 3.2 × 103 aseptic, purified, cryopreserved, vialed Plasmodium falciparum (Pf) strain NF54 sporozoites, PfSPZ Challenge (NF54), has been used for controlled human malaria infection (CHMI) in the United States, 4 European countries, and 6 African countries. In nonimmune adults, this results in 100% infection rates. We conducted a double-blind, randomized, dose-escalation study to assess the infectivity of the 7G8 clone of Pf (PfSPZ Challenge [7G8]). Results showed dose-dependent infectivity from 43% for 8 × 102 PfSPZ to 100% for 4.8 × 103 PfSPZ. PfSPZ Challenge (7G8) will allow for more complete assessment by CHMI of antimalarial vaccines and drugs.
