The Role of Potassium Channels in Working Memory Impairments of Chronic Cocaine Users
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age20-50
SponsorBoris Quednow
About this trial
The study aims to address the neurobiological basis of cognitive impairments in chronic cocaine users by investigating the potential impact of an acute potassium channel blockade on working memory performance and other cognitive functions.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Current diagnosis of mild, moderate, or severe CoUD according to DSM-5
Minimum cocaine use of 1g/month in the last three months
Cocaine as the primary drug of consumption
Willingness to abstain from cocaine use at least 72 hours before prior to each study visit
Disqualifiers
Presence or history of severe neurological disorders or head injuries
Current diagnosis of an acute or chronic infectious disease
If applicable: pregnancy and breastfeeding
Lifetime history of any epileptic seizures
Trial design
Design model
Crossover
Treatments tested in this trial
4-aminopyridine (4-AP)
DrugTwo doses of fampridine administered during one of the two experimental test sessions.
Placebo
DrugMatching placebo administered during one of the two experimental test sessions.
Treatment groups
40 Participants
are divided into 2 treatment groupsGroup A: Sequence ABExperimental treatment 2 interventions
Group B: Sequence BAExperimental treatment 2 interventions
Trial outcomes
Primary outcomes
1
Global Working Memory Performance
Working memory performance will be assessed using a cognitive test battery covering different domains of working memory, including visuo-spatial (Spatial Working Memory \[SWM\], total errors; Paired Associates Learning \[PAL\], first trial memory score) and verbal-numeric components (Letter Number Sequencing Task \[LNST\], total score; Letter N-Back Task, discrimination index d'). Individual test scores will be standardized (z-transformation) and combined into a global working memory score according to Vonmoos et al (2013).
Time frame
Baseline and during both experimental sessionsSecondary outcomes
1
Neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP)
Neurofilament light chain (NfL), a marker of axonal integrity, and glial fibrillary acidic protein (GFAP), a marker of microglia activation, levels will be analysed to assess potential drug challenge-related brain structural remodelling or to predict the effect of potassium challenge blockade.
Time frame
Baseline and during both experimental sessions2
Subjective ratings of current mood and craving
Subjective ratings of current mood (affective state, stress) and craving, pre- and post-cue exposure. Current affective state will be assessed using the Positive and Negative Affect Schedule (PANAS; positive affect range: 10-50, negative affect range: 10-50) and visual analog scales (VAS; range 0-100, with higher scores indicating greater levels) of affective state and stress burden. Current cocaine craving will be assessed using the Cocaine Craving Questionnaire-Brief (CCQ-Brief; total score range: 10-70, with higher scores representing worse outcomes) and visual analog scales (VAS; range 0-100, with higher scores indicating greater levels) of craving intensity, distinguishing between wanting, needing and having the urge for cocaine.
Time frame
Baseline and during both experimental sessions3
Adverse effects of the study drug
Potential adverse effects of the study drug will be assessed using the List of Complaints and visual analog scales (VAS; range 0-100, with higher scores indicating greater levels) of perceived effects of the substance, dizziness, drowsiness, nausea and impaired concentration.
Time frame
During both experimental sessions4
Plasma concentration
Plasma concentration of the study drug
Time frame
During both experimental sessionsSponsors and contacts
Click on the lead sponsor to view all of their trials.
Boris Quednow
Lead sponsor
Psychiatric University Hospital, Zurich
Sponsor institution
University of Zurich
Collaborator
Source ClinicalTrials.gov