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Non-small cell lung carcinoma (NSCLC) is among the most lethal lung cancers responsible for 80-85% of death. α v β 3 integrin receptor subtype has been identified as a lung cancer biomarker since its expression correlates with tumor progression and metastasis. The extracellular domain of the receptor forms a binding site for RGD-based sequences. Therefore, specific targeting of α v β 3 integrin receptors by these short peptides can be an excellent candidate for cancer imaging and therapy. In this research, the radiolabeling of DOTA-E(cRGDfK) 2 with 177 Lu was efficiently implemented. The Log P value, in vivo, in vitro, metabolic stability, cellular uptake and specific binding of the radiopeptide was determined. The tumor targeting capacity and the therapeutic potential of the radiotracer was studied in A549 tumor-bearing mice. Imaging studies at different time intervals were performed by SPECT/CT. Radiochemical purity of more than 99% and Log P of -3.878 was obtained for 177 Lu-labelled peptide. Radiotracer showed favorable in vivo, in vitro and metabolic stability. The radiopeptide dissociation constant (K d ) was 15.07 nM. Radiopeptide specific binding was more than 95%. Biodistribution studies showed high accumulation of the radiopeptide in tumor and rapid excretion by urinary route. Maximum tumor uptake was at 4 h post-injection. Following administration of this radiopeptide to mice, not only tumor growth was suppressed, but significant tumor shrinkage was also observed. In conclusion, this radiopeptide can be employed for staging, follow-up imaging and as peptide receptor radionuclide therapeutic agent allowing efficient therapy for NSCLC and other cancers overexpressing α v β 3 integrin receptors., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)