To determine potential differences between the potencies and efficacies of Chol-siRNA polyplexes and Chol-DsiRNA polyplexes against STAT3 mRNA in primary murine syngeneic breast tumors after IV administration, we intravenously administered increasing equimolar doses of Chol-siSTAT3 or Chol-DsiSTAT3 or a single maximum equimolar dose of inactive Chol-siCTRL or inactive Chol-DsiCTRL complexed with PLL[30]-PEG[5K] at the indicated N/P ratio and compared normalized murine STAT3 mRNA copy numbers in early-stage primary 4T1 breast tumors to vehicle alone by RT-ddPCR (Figure 3A). The gene discussed is STAT3; the disease is breast neoplasm.