This is a Phase 1 open-label study of SN2310 Injectable Emulsion in patients with advanced solid malignancies who have failed conventional therapy. SN2310 Injectable Emulsion will be administered intravenously every 21 days. The study is designed to determine the maximum tolerated dose and dose-limiting toxicity of SN2310 Injectable Emulsion; to characterize the pharmacokinetics of SN2310 and SN-38 following intravenous administration of SN2310 Injectable Emulsion; to evaluate side effects as a function of dose level; and, to observe any anti-tumor effects of SN2310 Injectable Emulsion.