Sodium stibogluconate (Stibogluconate trisodium nonahydrate) is a potent inhibitor of protein tyrosine phosphatase. Sodium stibogluconate inhibits 99% of SHP-1, SHP-2 and PTP1B activity at 10, 100, 100 μg/mL, respectively. IC50 & Target: Phosphatase^[1] In Vitro: Sodium stibogluconate (Stibogluconate trisodium nonahydrate) inhibits 99% of SHP-1 activity at 10 μg/mL, a therapeutic concentration of the drug for leishmaniasis. Similar degrees of inhibition of SHP-2 and PTP1B required 100 μg/mL Sodium stibogluconate. The inhibition of cellular PTPases by the Sodium stibogluconate is suggested by its rapid induction of tyrosine phosphorylation of cellular proteins in Baf3 cells and its augmentation of IL-3-induced Janus family kinase 2/Stat5 tyrosine phosphorylation and proliferation of Baf3 cells. The augmentation of the opposite effects of GM-CSF and IFN-α on TF-1 cell growth by Sodium stibogluconate indicate its broad activities in the signaling of various cytokines^[1]. In Vivo: Sodium stibogluconate (Stibogluconate trisodium nonahydrate) induces 61% growth inhibition of Renca tumors in BALB/c mice coincident with an increase (2-fold) in tumor-infiltrating macrophages. A combination of Sodium stibogluconate and IL-2 is more effective in inhibiting tumor growth (91%) and inducing tumor-infiltrating (4-fold), whereas IL-2 alone has little effect^[2].