A recent Journal article by Martinez and others, concerned the determination of the efficacy of pentavalent antimony, the primary agent for leishmaniasis, against Leishmania braziliensis and L. donovani amastigotes in a human macrophage cell line (U937). The dose of Pentostam (sodium stibogluconate) expected to 50% inhibit growth (ED50) of both species was “10 and 6 ng/ml, respectively.” Doses >100 ng/ml were not tested and there was no dose that inhibited >70% of parasite growth.
In the Discussion section of this article, the authors state that “the growth inhibition of L. b. braziliensis and L. donovani (Khartoum) by sodium stibogluconate is similar to that reported in other established systems.14” Reference 14 is work of our group. As the title indicates, it concerns the antileishmanial activities of experimental purine analogs, not of Pentostam. However, we have reported the activity of Pentostam against L. tropica (now called L. major) and L. donovani amastigotes in human monocyte-derived macrophages in other work.