A novel self-nanoemulsifying formulation for sunitinib: Evaluation of anticancer efficacy

Breast cancer is the top cancer and a main cause of death among women. The incidence of this cancer is increasing in the world. Sunitinib maleate is an oral, small-molecule, multi-targeted receptor tyrosine kinase inhibitor that inhibits tumor cell proliferation and angiogenesis, and has been administrated as an anticancer drug. Self-nanoemulsifying drug delivery system (SNEDDS) is an isotopic mixture of an oil, a surfactant and usually a co-surfactant, which can spontaneously form fine oil-in-water nanoemulsion in aqueous media. Here, a SNEDDS composed of 15% ethyl oleate (as an oil phase), 30% tween 80 (as a surfactant), and 55% PEG 600 (as a co-surfactant) was prepared and developed as a carrier for sunitinib. The average droplet size of sunitinib-loaded SNEDDS was 29.5±6.3nm with a stability of more than one month. Sunitinib release from SNEDDS was enhanced accompanied by a controlled dissolution of the drug. Cytotoxicity studies on 4T1 and MCF-7 cell lines indicated a toxicity enhancement in sunitinib by SNEDDS. To inspect the bioavailability of the drug-loaded SNEDDS after oral administration with a dose of 50mgkg^-1, the maximum plasma concentration and the mean area under the plasma concentration-time curve were measured. It was found that these parameters were increased 1.45- and 1.24-times respectively, compared to a drug suspension.