Innovative approaches for cocaine pharmacotheraphy: the case of rimonabant.

In today’s society, cocaine abuse and relapse remains a growing problem. Abstinent cocaine abusers have difficulties staying “clean”, and good treatment strategies for preventing relapse to cocaine abuse are lacking. Dopamine receptor availability in the striatum is linked closely to dependence and relapse disorders, and new imaging techniques allow us to investigate these effects.



Our goal is to build knowledge for an evidence-based strategy to reduce relapse in cocaine addicts. To accomplish this, we propose to:

a) investigate effects of prolonged treatment with rimonabant on the availability of DA D2 receptors in abstinent cocaine addicts using SPECT;

b) examine the acute and prolonged effects of Rimonabant on impulse control, motivational strength of drug cues, and brain activation patterns of cocaine-addicted patients compared to non-addicted controls (using fMRI and EEG); and,
c) examine the extent to which these processes predict relapse.

Rimonabant increases the availability of dopamine D2 receptors in the brain's striatal area. This subsequently reduces cocaine craving and decreases relapse in human detoxified cocaine users.

SPECT will be performed at baseline, and after 2 months of rimonabant/placebo intake.

fMRI will be performed at baseline, after the first intake of rimonabant/placebo and after 2 months of medication intake.
Neuropsychological assessments will be assessed at consequent timepoints throughout the trial.

Rimonabant or placebo will be administered for 2 months. [123I]IBZM SPECT will be performed at baseline and at the end of the experiment to assess the prolonged effects of rimonabant on DA D2 receptor availability in vivo. Additionally, fMRI and EEG will be performed at baseline, after the first tablet, and after two months, together with different neuropsychological assessments.