PMID-24239329 – Tesofensine Dopamine Transporter Occupancy PET

PMID-24239329 – Tesofensine Dopamine Transporter Occupancy PET

Appel L, Bergstrom M, Buus Lassen J, Langstrom B. Tesofensine, a novel triple monoamine re-uptake inhibitor with anti-obesity effects: dopamine transporter occupancy as measured by PET. Eur Neuropsychopharmacol. 2014;24(2):251-261.

Quick Reference

Property Value
PMID 24239329
DOI 10.1016/j.euroneuro.2013.10.007
Year 2014
Journal European Neuropsychopharmacology
Study Type Observational
Evidence Level III
Sample Healthy volunteers (PET imaging study)
Peptide(s) Studied Tesofensine

Key Findings

  • PET imaging confirmed tesofensine occupies dopamine transporters (DAT) in the human brain in vivo
  • DAT occupancy at therapeutic doses (0.5 mg) was approximately 30-40%
  • This occupancy level is below the threshold associated with abuse potential (~50-60% DAT occupancy)
  • Norepinephrine transporter (NET) and serotonin transporter (SERT) occupancy also confirmed
  • The triple reuptake inhibition profile was validated in vivo using [11C]PE2I as DAT ligand
  • Pharmacokinetic-pharmacodynamic modeling supported once-daily dosing

Study Design

PET neuroimaging study using [11C]PE2I as a DAT-selective radioligand. Subjects received tesofensine at clinical doses and underwent serial PET scans to quantify transporter occupancy over time.

Limitations

  • Small sample size typical of PET studies
  • Only measured DAT occupancy directly; NET and SERT occupancy inferred
  • Healthy volunteers may not reflect occupancy in obese populations

Clinical Relevance

Critical pharmacological study confirming the mechanism of action in humans. The relatively modest DAT occupancy (~30-40%) at therapeutic doses suggests lower abuse liability compared to stimulants like amphetamine (>50% DAT occupancy). This supports tesofensine's positioning as a weight loss agent with acceptable CNS safety profile, distinct from classical stimulants.

Related

#research #observational #tesofensine #evidence-level-III