Antimony-based drugs have remained the major therapeutic treatment in the clinic for decades. The use of antimony chemotherapy increases the survival rate of those patients with Leishmania infection to over 90%. Although its main action is concentrated only on the visceral leishmaniasis, other forms of the disease are also. Several other antimony compounds including antimony bis(4,5-dihydroxybenzene-3,5-disulphonate) tibophen), meglumine antimonate (Glucantime), sodium antimony(III) gluconate (Triostam) and sodium stibogluconate (Pentosam), have also been used clinically for the treatment of different forms of leishmaniasis. Since pentavalent  antimonials have a more efficient therapeutic index and are 10 times less toxic to humans than their trivalent analogues, they have become the first choices of chemotherapy. 

The carbohydrates in the drugs increase the solubility of antimony and are responsible for the delivery of the antimony to the macrophages, where the protozoa that cause leishmaniasis undergo division. Sodium stibogluconate is an SbV complex of a carbohydrate (gluconic acid) and was first used for the treatment of Leishmania during the mid-1930s and is still predominantly used in English-speaking countries.  

The structure of the complex remains unknown. It is commonly believed that the agent contains only one 746Da species, probably a dimer. However, polymeric species with molecular weight up to 4 kDa may also be present in solution. Meglunmine antimonate has also been used as the first-choice drug predominantly in French- and Spanish-speaking countries. A series of oligomers of antimony and N-methyl-D-glucamine (NMG) has been observed with the general formula of Sbn(NMG)nþ1 or Sbn(NMG)n.  The major component of meglunmine antimonate is Sb(NMG)2, with a formula mass of 507 Da.  Anti-cancer activities of antimony agents have also been reported. Antimony tartrate has been found to be cytotoxic in vitro to various lung cancer cell lines Proposed structures of clinically used SbV drugs: (a) Pentosam and (b) Glucantime with IC50 ranging from 4.2 to 322 mg/ml. The complex was found to be as effective as those clinically used anti-cancer drugs such as cisplatin and doxorubicin. The anti-cancer activity of sodium stibogluconate that synergizes with interferon (IFN) to eradicate IFN resistant human cancer cells both in vitro and in mouse models has been reported.  It was shown that the complex functions as a protein tyrosine phosphatase (PTPase) inhibitor in cancer cells and augments IFN signaling.

The activity of Src homology PTPase1 (SPH-1) was almost completely inhibited by sodium stibogluconate at 10 mg/ml. The inhibition is likely to target the catalytic domain of PTPase.Interference with the intracellular tyrosine phosphorylation resulted in the disruption of the cell proliferation, differentiation and signaling activities, with consequent anti-tumor activity.Since sodium stibogluconate is a polymeric complex, the inhibitory activities of different fractions from HPLC toward PTPase have been determined. It has become evident that a small portion of the fractions in sodium stibogluconate is mainly responsible for the PTPase inhibitory activity and that interestingly it is not solely defined by antimony contents. It might be feasible to develop more specific and effective inhibitors for phosphatase-targeted anti-cancer therapeutics through the screening of sodium stibogluconate-related compounds, comprised of antimony conjugated to different organic moieties.

Sodium stibogluconate appears to be a better inhibitor than suramin, a compound known for its anti-neoplastic activity against several types of cancers and new therapeutic applications of sodium stibogluconate targeting the phosphatases have then been explored.