Effects of Isotretinoin on CYP2D6 Activity

Phase 4

Completed

• Conditions: CYP2D6 Polymorphism
• Interventions: Drug: Isotretinoin; Drug: dextromethorphan

• Registration Number: NCT03076021
• Lead Sponsor: University of Washington

Brief Summary

Specific Aim: To investigate if isotretinoin (13-cis-retinoic acid) administration decreases CYP2D6 activity in adolescent patients.

Detailed Description

In this aim, we will conduct a drug-drug interaction study evaluating the effects of 13-cis-retinoic acid on non-induced CYP2D6 activity in adolescent patients. Secondary analysis will evaluate the relationship between retinoid concentrations and CYP2D6 activity in these special populations

Study Timeline

• Study Start: 2016-07-26
• Study First Submitted: 2017-03-06
• Study First Submitted QC: 2017-03-06
• Study First Posted: 2017-03-09
• Primary Completion: 2023-11-27
• Study Completion: 2023-11-27
• Results First Submitted: 2024-12-09
• Status Verified: 2025-01
• Results First Submitted QC: 2025-01-03
• Last Update Submitted: 2025-01-03
• Results First Posted: 2025-01-28
• Last Update Posted: 2025-01-28

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 33

Inclusion Criteria

• Non-pregnant
• ≥ 12 years
• Patients with severe acne that are expected to receive isotretinoin for therapeutic reasons

Exclusion Criteria

• Weight < 80 lbs
• Allergy or adverse reaction to dextromethorphan, vitamin A or isotretinoin
• Pregnant or planning to become pregnant
• Unable to follow isotretinoin risk evaluation and mitigation strategies (REMS) program (also known as iPLEDGE program)
• Chronic or persistent cough accompanying asthma, smoking or chronic obstructive pulmonary disease,
• Productive cough,
• Fever,
• Known kidney disease,
• Known liver disease,
• Diabetes
• Obesity, body mass index ≥ 30 kg/m2
• Bipolar disease,
• Attention deficit disorder,
• Social phobia,
• Concurrent or use within 14 days of drugs known to interact with dextromethorphan or cytochrome P450 2D6 (CYP2D6) or drugs known to increase the risk of adverse effects from dextromethorphan
• Concurrent use of any other product containing dextromethorphan
• Consuming foods, beverages or dietary supplements known to interact with dextromethorphan or CYP2D6
• Unable to give written informed consent/assent,
• Inability to fast for 4 hours prior to study.
• Wards of the State

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Adolescents	Isotretinoin	dextromethorphan pre- and post isotretinoin
Adolescents	dextromethorphan	dextromethorphan pre- and post isotretinoin

Primary Outcome Measures

Name	Time	Method
CYP2D6 Activity as Measured by the Molar Concentration Ratio of Dextromethorphan (DM)/Dextrophan (DX)	1 week to 6 months	dextromethorphan (DM)/dextrophan (DX) molar concentration Metabolic Ratio. The metabolic ratio is unit-less as the molar concentrations cancel out.

Trial Locations

Locations (1)

University of Washington; 🇺🇸 Seattle, Washington, United States