Uptake kinetics of the somatostatin receptor ligand [86Y]DOTA-DPhe1- Tyr3-octreotide ([86Y]SMT487) using positron emission tomography in non-human primates and calculation of radiation doses of the 90Y-labelled analogue

Eur J Nucl Med. 1999 Apr;26(4):358-66. doi: 10.1007/s002590050398.


[90Y]DOTA-DPhe1-Tyr3-octreotide ([90Y]-SMT487) has been suggested as a promising radiotherapeutic agent for somatostatin receptor-expressing tumours. In order to quantify the in vivo parameters of this compound and the radiation doses delivered to healthy organs, the analogue [86Y]DOTA-DPhe1-Tyr3-octreotide was synthesised and its uptake measured in baboons using positron emission tomography (PET). [86Y]DOTA-DPhe1-Tyr3-octreotide was administered at two different peptide concentrations, namely 2 and 100 microg peptide per m2 body surface. The latter concentration corresponded to a radiotherapeutic dose. In a third protocol [86Y]DOTA-DPhe1-Tyr3-octreotide was injected in conjunction with a simultaneous infusion of an amino acid solution that was high in l-lysine in order to lower the renal uptake of radioyttrium. Quantitative whole-body PET scans were recorded to measure the uptake kinetics for kidneys, liver, lung and bone. The individual absolute uptake kinetics were used to calculate the radiation doses for [90Y]DOTA-DPhe1-Tyr3-octreotide according to the MIRD recommendations extrapolated to a 70-kg human. The highest radiation dose was received by the kidneys, with 2.1-3.3 mGy per MBq [90Y]DOTA-DPhe1-Tyr3-octreotide injected. For the 100 microg/m2 SMT487 protocol with amino acid co-infusion this dose was about 20%-40% lower than for the other two treatment protocols. The liver and the red bone marrow received doses ranging from 0.32 to 0.53 mGy and 0.03 to 0.07 mGy per MBq [90Y]DOTA-DPhe1-Tyr3-octreotide, respectively. The average effective dose equivalent amounted to 0. 23-0.32 mSv/MBq. The comparatively low estimated radiation doses to normal organs support the initiation of clinical phase I trials with [90Y]DOTA-DPhe1-Tyr3-octreotide in patients with somatostatin receptor-expressing tumours.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anesthesia
  • Animals
  • Female
  • Image Processing, Computer-Assisted
  • Ligands
  • Male
  • Octreotide / analogs & derivatives*
  • Octreotide / blood
  • Octreotide / pharmacokinetics
  • Octreotide / urine
  • Papio
  • Quality Control
  • Radiometry / methods*
  • Radiopharmaceuticals / blood
  • Radiopharmaceuticals / pharmacokinetics*
  • Radiopharmaceuticals / urine
  • Receptors, Somatostatin / metabolism*
  • Tomography, Emission-Computed
  • Yttrium Radioisotopes / pharmacokinetics


  • Ligands
  • Radiopharmaceuticals
  • Receptors, Somatostatin
  • Yttrium Radioisotopes
  • Octreotide
  • Edotreotide