A Phase 1 Study To Evaluate The Effect Of Dimebon On The Pharmacokinetics Of Dextromethorphan

A Phase 1, Randomized, Open-Label, Two-Way Crossover Study To Evaluate The Steady-State Effect Of Dimebon [PF-01913539] On The Single-Dose Pharmacokinetics Of The CYP2D6 Substrate Dextromethorphan In Healthy Subjects

Status

Completed

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00788047

Enrollment

Registered

2008-11-10

Start date

2008-11-30

Completion date

2009-01-31

Last updated

2009-03-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Alzheimer Disease, Huntington Disease

Brief summary

This drug-drug interaction study is being conducted to evaluate the potential effect of Dimebon on the pharmacokinetics on dextromethorphan, a probe substrate of the cytochrome P450 2D6 (CYP2D6) enzyme, after multiple dose administration to healthy adult subjects.

Interventions

DRUGDextromethorphan

Dextromethorphan HCl 30 syrup single dose

DRUGDimebon + Dextromethorphan

Dimebon 20 mg tablets given three times daily for 14 days plus Dextromethorphan HCl 30 syrup single dose administered on Day 12

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to 55 Years

Healthy volunteers

Yes

Inclusion criteria

* Healthy adult subjects. * Extensive or ultra-rapid metabolizers of CYP2D6 substrates, predicted by genotype.

Exclusion criteria

* Existence of significant medical conditions that would impact study results or pose unacceptable risks to study subjects. * Pregnant or nursing females or females of childbearing potential who are unwilling or unable to use an acceptable method of contraception. * Use of prescription or nonprescription drugs and dietary supplements within 7 days prior to the first dose of study medication.

Design outcomes

Primary

Measure	Time frame
Dextromethorphan exposure in combination with Dimebon 20 mg TID relative to Dextromethorphan exposure alone	Day 12

Secondary

Measure	Time frame
Safety and Tolerability (Adverse Events, Vital Signs, Clinical Labs, Electrocardiograms)	Day 15
Dextrorphan (the metabolite of dextromethorphan) exposure	Day 12

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026