The Role of Potassium Channels in Working Memory Impairments of Chronic Cocaine Users

NCT07532460 | Not Yet Recruiting

• 1 other identifier: 2025-01432
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Cognitive Impairments in Cocaine Use Disorder

Keywords

cognitive impairments; cocaine use disorder; potassium channels; working memory; 4-aminopyridine; fampridine

Outcome Measures

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).

  Baseline and during both experimental sessions

Secondary Outcomes (6)

• Neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP)

  Baseline and during both experimental sessions

• Subjective ratings of current mood and craving

  Baseline and during both experimental sessions

• Impulsivity

  Baseline

• Adverse effects

  During both experimental sessions

• Plasma concentration

  During both experimental sessions

Study Arms (2)

Sequence AB

EXPERIMENTAL

Participants receive fampridine (A) in one experimental session and placebo (B) in the other, in the order A then B.

Drug: 4-aminopyridine (4-AP); Drug: Placebo

Sequence BA

EXPERIMENTAL

Participants receive placebo (B) in one experimental session and fampridine (A) in the other, in the order B then A.

Drug: 4-aminopyridine (4-AP); Drug: Placebo

Interventions

4-aminopyridine (4-AP) DRUG

Two doses of fampridine administered during one of the two experimental test sessions.

Sequence AB; Sequence BA

Placebo DRUG

Matching placebo administered during one of the two experimental test sessions.

Sequence AB; Sequence BA

Eligibility Criteria

• Age: 20 Years - 50 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• 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
• Ability to read, understand and provide written informed consent
• To be sufficiently fluent in German
• Age between 20 and 50 years
• Body mass index (BMI) between 19 and 30 kg/m2
• If applicable: luteal phase of the menstrual cycle
• For individuals with childbearing potential: use of contraceptive measures

You may not qualify if:

• 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
• Lifetime diagnosis of a cardiovascular disease, specifically arrhythmia and long QT syndrome
• Clinically significant laboratory or ECG abnormality that could be a safety issue in the study
• Lifetime diagnosis of liver or kidney disease including moderate or severe renal impairment (creatinine clearance \< 50 ml/min)
• Known hypersensitivity or allergy to 4-aminopyridine
• Use of potassium channel blockers within the last 3 months
• Use of psychotropic medication within the last 7 days
• Use of inhibitors of the organic cation transporter 2 (OCT2), such as cimetidine
• Lifetime diagnosis of schizophrenia, bipolar disorder, obsessive-compulsive disorder, or autism spectrum disorder according to DSM-5
• Diagnosis of a current episode of depression
• Current diagnosis of a moderate or severe substance use disorder other than CoUD according than DSM-5
• Daily cannabis consumption in the past three months

Sponsors & Collaborators

• Boris Quednow: lead
• University of Zurich: collaborator

Study Sites (1)

University Hospital of Psychiatry Zurich

Zurich, Canton of Zurich, 8008, Switzerland

Location

MeSH Terms

Conditions

Cognitive Dysfunction

Interventions

4-Aminopyridine

Condition Hierarchy (Ancestors)

Cognition Disorders; Neurocognitive Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Aminopyridines; Amines; Organic Chemicals; Pyridines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Central Study Contacts

Prof. Dr. rer. nat. Boris B. Quednow, Dr. rer. nat.

CONTACT

+41 58 384 27 77; quednow@bli.uzh.ch

Laura V Schurek, M. Sc.

CONTACT

+41 58 384 26 16; studie-potchicud@bli.uzh.ch

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Full Professor for Experimental Pharmacopsychology and Psychological Addiction Research

Study Record Dates

• First Submitted: April 8, 2026
• First Posted: April 16, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): August 1, 2027
• Last Updated: April 16, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

CH (1)