DOTA-LM3 TFA is a somatostatin receptor (SSTR) antagonist. LM3 refers to p-Cl-Phe- cyclo(D-Cys-Tyr-D-4-amino-Phe(carbamoyl)-Lys-Thr-Cys)D-Tyr- NH2, as well as a somatostatin antagonist. DOTA-LM3 TFA is often isotopically labeled for tracing tumors in vivo, such as 177Lu-DOTA-LM3 TFA and 68 Ga-DOTA-LM3 TFA. 68 Ga-DOTA-LM3 TFA shows favorable biodistribution, high tumor uptake, good tumor retention, and few safety concerns. 177Lu-DOTA-LM3 TFA can be used for research in DOTATOC-negative liver metastases, such as pancreatic NET and extensive tumor thrombosis[1][2]. DOTA-LM3 (TFA) can be used for the synthesis/research of Radionuclide-Drug Conjugates (RDCs).