BALB/cAnNCrl mice were quarantined, shaved, and induced with CT26 tumors. Tumors were monitored until 60-70 mm³, then mice randomized into groups: naïve, CTRL, and pmIL12 GET at 0.5, 1, and 2 mg/ml. Pharmacodynamics, pharmacokinetics, and systemic toxicology were assessed, including tumor growth, transgene expression, plasmid DNA copies, and organ pathology. Statistical analysis used GraphPad Prism 9.