Effects of Isotretinoin on CYP2D6 Activity

University of Washington

Status and phase: Completed; Phase 4

Conditions: CYP2D6 Polymorphism

Treatments: Drug: Isotretinoin; Drug: dextromethorphan

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT03076021

R01GM124264 (U.S. NIH Grant/Contract)

STUDY00002324

Details and patient eligibility

About

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

Full 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

Enrollment: 33 patients

Sex: All

Ages: 12+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Other

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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33 participants in 1 patient group

Adolescents

Other group

Description:

dextromethorphan pre- and post isotretinoin

Treatment:

Drug: dextromethorphan

Drug: Isotretinoin