Fig. 3
From: Long-acting injectable atovaquone nanomedicines for malaria prophylaxis
Efficacy testing of ATQSDN7. a Experimental scheme. Mice dosed on day 0 with placebo, oral atovaquone or intramuscular nanoparticle atovaquone formulation were challenged once with intravenous P. berghei sporozoites at a given interval after dosing (28 days is depicted). For 42 days after challenge, blood samples were obtained and monitored for parasitemia (dots). b Prophylactic efficacy of intramuscular ATQSDN7. Cohorts of mice treated on day 0 with indicated doses of ATQSDN7 were challenged at a given interval after dosing (red arrows). Black lines, dose-to-challenge interval; grey lines, 42 days follow-up monitoring period. Prophylaxis was successful (circles) if, in two independent experiments (each with a cohort of 3–5 mice) all animals remained parasite-free for 42 days after challenge. Prophylaxis failed (x) if patent parasitemia was detected in any mouse in the cohort. For failed regimens the actual intervals between challenge and failure are not depicted. Not shown, all concurrent placebo recipients developed parasitemia, and all concurrent oral atovaquone controls failed challenge on or before 7 days after dosing. In all comparisons, successful prophylaxis with intramuscular ATQSDN7 was superior to no-drug control at p ≤ 0.003 (Fisher’s exact test)
