PURPOSE: We report the preclinical evaluation of potent long-acting [ METHODS: The pharmacokinetic, biodistribution, and safety studies were evaluated in healthy female and/or male BALB/c mice after intravenous injections of [ RESULTS: Pharmacokinetics confirmed a prolonged clearance half-life (40.27 ± 9.23 h) while biodistribution in healthy male and female BALB/c mice was similar, with prolonged blood circulation that peaked at 6 h. Biodistribution in subcutaneous xenograft models of NCI-H524 and NCI-H727 showed consistent tumor-uptake with SSTR2-overexpression while the projected human effective doses for males and females were 61.7 and 83.7 millisievert/megabecquerel, respectively. 2 × 34 kBq of [ CONCLUSIONS: [