Molecular Imaging and Biology

, Volume 15, Issue 4, pp 384–390 | Cite as

Whole-Body Biodistribution and Radiation Dosimetry of the Cannabinoid Type 2 Receptor Ligand [11C]-NE40 in Healthy Subjects

  • Rawaha Ahmad
  • Michel Koole
  • Nele Evens
  • Kim Serdons
  • Alfons Verbruggen
  • Guy Bormans
  • Koen Van Laere
Brief Article



The type 2 cannabinoid receptor (CB2R) is part of the human endocannabinoid system and is involved in central and peripheral inflammatory processes. In vivo imaging of the CB2R would allow study of several (neuro)inflammatory disorders. In this study we have investigated the safety and tolerability of [11C]-NE40, a CB2R positron emission tomography (PET) ligand, in healthy human male subjects and determined its biodistribution and radiation dosimetry.


Six healthy male subjects (age 20–65 years) underwent a dynamic series of nine whole-body PET/CT scans for up to 140 min, after injection of an average bolus of 286 MBq of [11C]-NE40. Organ absorbed and total effective doses were calculated through OLINDA.


[11C]-NE40 showed high initial uptake in the spleen and a predominant hepatobiliary excretion. In the brain, rapid uptake and swift washout were seen. Organ absorbed doses were largest for the small intestine and liver, with 15.6 and 11.5 μGy/MBq, respectively. The mean effective dose was 3.64 ± 0.81 μSv/MBq. There were no changes with aging observed. No adverse events were encountered.


This first-in-man study of [11C]-NE40 showed an expected biodistribution compatible with lymphoid tissue uptake and appropriate fast brain kinetics in the healthy human brain, underscoring the potential of this tracer for further application in central and peripheral inflammation imaging. The effective dose is within the typical expected range for 11C ligands.

Key words

Biodistribution Dosimetry Positron emission tomography [11C]-NE40 CB2R 



Financial support of the European Commission (FP7/2007-2013, INMiND, grant agreement no. 278850) is gratefully acknowledged. We also thank Kwinten Porters, Mieke Steukers, Tjibbe De Groot, Marva Bex, and Lena Sojka for their contribution.

Conflict of Interest

The authors have no conflicts of interest.


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Copyright information

© World Molecular Imaging Society 2013

Authors and Affiliations

  • Rawaha Ahmad
    • 1
  • Michel Koole
    • 1
  • Nele Evens
    • 2
  • Kim Serdons
    • 2
  • Alfons Verbruggen
    • 2
  • Guy Bormans
    • 2
  • Koen Van Laere
    • 1
  1. 1.Division of Nuclear MedicineUniversity Hospital LeuvenLeuvenBelgium
  2. 2.Laboratory for Radiopharmacy, University Hospital LeuvenKU LeuvenLeuvenBelgium

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