The results of our therapeutic studies met key endpoint criteria at substantially lower particle concentrations (i.e., 2 μmol L−1) than previously utilized in our non-targeted theranostic work.[54,55] Using a “hit and run” delivery approach for the HER2-targeted drug-immune conjugate particle therapy, statistically significant (p < 0.05) improvements in tumor regression were observed over the non-targeted therapy with subsequent eradication, confirmed by histopathology. The gene discussed is ERBB2; the disease is neoplasm.