68Ga-DOTA-LM3

68Ga-DOTA-LM3 is a radiopharmaceutical diagnostic agent designed for positron emission tomography (PET) imaging of neuroendocrine tumors (NETs). It is composed of the somatostatin receptor (SSTR) antagonist peptide LM3 (p-Cl-Phe-cyclo(D-Cys-Tyr-D-Trp-Lys-Thr-Cys)-D-Tyr-NH2), which is linked to the chelator DOTA and radiolabeled with the positron-emitting isotope Gallium-68. While traditional SSTR-targeting tracers like 68Ga-DOTATATE are agonists that internalize into the cell upon binding, 68Ga-DOTA-LM3 is an antagonist that binds to the receptor (primarily the SSTR2 subtype) without inducing internalization. Clinical studies have demonstrated that SSTR antagonists can provide superior tumor uptake and higher tumor-to-background ratios compared to agonists, likely due to their ability to bind to a broader range of receptor conformations and a higher number of binding sites. This agent is primarily utilized for the localization, staging, and treatment planning of patients with well-differentiated NETs, often serving as a companion diagnostic for the therapeutic counterpart 177Lu-DOTA-LM3.

Other names

[68Ga]Ga-DOTA-LM3Gallium-68 DOTA-LM3Gallium68 DOTA-LM3Gallium 68 DOTA-LM368Ga-labeled DOTA-LM3