Trial Outcomes & Findings for Effects of Isotretinoin on CYP2D6 Activity (NCT NCT03076021)

NCT ID: NCT03076021

Last Updated: 2025-01-28

Results Overview

dextromethorphan (DM)/dextrophan (DX) molar concentration Metabolic Ratio. The metabolic ratio is unit-less as the molar concentrations cancel out.

• Recruitment status: COMPLETED
• Study phase: PHASE4
• Target enrollment: 33 participants
• Primary outcome timeframe: 1 week to 6 months
• Results posted on: 2025-01-28

Participant Flow

Participant milestones

Measure	Individuals Expected to Receive Isotretinoin for Therapeutic Reasons Each subject had 2 study days, one pre-isotretinoin treatment and one while receiving isotretinoin.
Pre-isotretinoin STARTED	33
Pre-isotretinoin COMPLETED	33
Pre-isotretinoin NOT COMPLETED	0
Isotretinoin STARTED	33
Isotretinoin COMPLETED	33
Isotretinoin NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Effects of Isotretinoin on CYP2D6 Activity

Baseline characteristics by cohort

Measure	Study Group n=33 Participants Individuals expected to receive isotretinoin for therapeutic reasons
Age, Continuous	23.5 years STANDARD_DEVIATION 6.0 • n=5 Participants
Sex: Female, Male Female	22 Participants n=5 Participants
Sex: Female, Male Male	11 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	7 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	1 Participants n=5 Participants
Race (NIH/OMB) White	25 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants
Region of Enrollment United States	33 participants n=5 Participants

PRIMARY outcome

Timeframe: 1 week to 6 months

Population: The number of subjects included in the analysis is less than the number that completed the study because only cytochrome P450 extensive metabolizers were included in the analysis. Each person served as their own control (pre-isotretinoin and with isotretinoin). Pre-isotretinoin study was completed prior to starting isotretinoin and then the same study was completed after the subject had been on isotretinoin for 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.

Outcome measures

Measure	Pre-isotretinoin n=24 Participants Individuals expected to receive isotretinoin for therapeutic reasons	With Isotretinoin n=24 Participants Individuals receiving isotretinoin for therapeutic reasons.
CYP2D6 Activity as Measured by the Molar Concentration Ratio of Dextromethorphan (DM)/Dextrophan (DX)	16.0 Ratio Interval 10.2 to 25.0	12.5 Ratio Interval 8.9 to 17.6

Adverse Events

Pre-isotretinoin

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

With Isotretinoin

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Mary Hebert

University of Washington

Phone: 206-616-5016

Email: mhebert@u.washington.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place