Passive immunization with HGN194 against heterologous clade C SHIV challenge in infant rhesus macaques.
(A) Experimental design. Group 1A infant RM (n = 4) were infused twice with 50 mg/kg of HGN194 on days −1 and 7. Group 1B (n = 2) received twice 1 mg/kg of HGN194. Four RM served as untreated controls. On day 0, all 10 animals were challenged intrarectally with 18 AID50 of SHIV-1157ipEL-p. (B) Plasma viral RNA loads after high-dose rectal challenge with SHIV-1157ipEL-p using a quantitative RT assay (detection limit: 50 copies/ml). (C) Average plasma mAb concentrations during the course of the study for Group 1A. (D) Plasma HGN194 concentration for Group 1B. Arrows in C and D indicate mAb treatments. Experiments in C and D were repeated twice or trice.