Trial Outcomes & Findings for Dextromethorphan in Fibromyalgia (NCT NCT03538054)

Last Updated: 2022-08-26

Results Overview

Daily self-reported widespread pain severity, rated on a 0 - 100 scale (0 = no pain and 100 = worst pain possible). Participants' daily scores from the last 4 weeks of each condition (placebo and dextromethorphan) were summed and then averaged across the 4-week time period.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

27 participants

Primary outcome timeframe

Daily over 4 weeks

Results posted on

2022-08-26

Participant Flow

27 participants attended the in-person screening visit and were enrolled into the study. Of the 27 enrolled, 19 met inclusion criteria and began the study protocol.

Participant milestones

Participant milestones
Measure	Placebo First, Then Dextromethorphan All participants first completed a 2 week baseline where they did not receive any medication. They then completed a 5 week placebo condition where they took one inert capsule in the morning and one at night. Following the placebo phase, participants completed 10 weeks of the dextromethorphan condition where they took one 10mg dextromethorphan in the morning, one 10mg dextromethorphan capsule at night.
Baseline Phase (2 Weeks) STARTED	19
Baseline Phase (2 Weeks) COMPLETED	18
Baseline Phase (2 Weeks) NOT COMPLETED	1
Placebo Phase (5 Weeks) STARTED	18
Placebo Phase (5 Weeks) COMPLETED	16
Placebo Phase (5 Weeks) NOT COMPLETED	2
Dextromethorphan Phase (10 Weeks) STARTED	16
Dextromethorphan Phase (10 Weeks) COMPLETED	14
Dextromethorphan Phase (10 Weeks) NOT COMPLETED	2

Reasons for withdrawal

Reasons for withdrawal
Measure	Placebo First, Then Dextromethorphan All participants first completed a 2 week baseline where they did not receive any medication. They then completed a 5 week placebo condition where they took one inert capsule in the morning and one at night. Following the placebo phase, participants completed 10 weeks of the dextromethorphan condition where they took one 10mg dextromethorphan in the morning, one 10mg dextromethorphan capsule at night.
Baseline Phase (2 Weeks) Physician Decision	1
Placebo Phase (5 Weeks) Withdrawal by Subject	2
Dextromethorphan Phase (10 Weeks) Withdrawal by Subject	2

Baseline Characteristics

Dextromethorphan in Fibromyalgia

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	All Study Participants n=14 Participants Participants first completed a 5-week placebo condition where they took one inert capsule in the morning, and one at night. They then completed a 10-week dextromethorphan condition where they took one 10 mg dextromethorphan capsule in the morning, and one at night.
Age, Continuous	47.07 years STANDARD_DEVIATION 10.74 • n=5 Participants
Sex: Female, Male Female	14 Participants n=5 Participants
Sex: Female, Male Male	0 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 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	3 Participants n=5 Participants
Race (NIH/OMB) White	11 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
Duration of fibromyalgia illness	10.19 years STANDARD_DEVIATION 6.90 • n=5 Participants
Fibromyalgia severity	22.14 units on a scale STANDARD_DEVIATION 3.76 • n=5 Participants
Widespread Pain Index score	13.79 units on a scale STANDARD_DEVIATION 2.91 • n=5 Participants
Symptom Severity Scale score	8.36 units on a scale STANDARD_DEVIATION 2.10 • n=5 Participants

PRIMARY outcome

Timeframe: Daily over 4 weeks

Population: All 14 participants underwent both the Dextromethorphan and Placebo conditions (within-subjects comparisons).

Outcome measures

Outcome measures
Measure	Dextromethorphan n=14 Participants Participant will take one dextromethorphan 10mg capsule in the morning and at night. Dextromethorphan: (1)10 mg, by mouth, twice daily every 12 hours.	Placebo n=14 Participants Participants will take one placebo capsule in the morning and at night. Placebo: 1 capsule, by mouth, twice daily every 12 hours.
Daily Self-reported Pain Severity	41.09 score/day Standard Deviation 24.32	45.55 score/day Standard Deviation 24.69

SECONDARY outcome

Timeframe: Daily over 4 weeks

Population: All 14 participants underwent both the Dextromethorphan and Placebo conditions (within-subjects comparisons).

Self-reported daily activity, rated from 0 - 100 where 0 is less daily activity and 100 is the most amount of daily activity. Participants' daily scores from the last 4 weeks of each condition (placebo and dextromethorphan) were summed and then averaged across the 4-week time period.

Outcome measures

Outcome measures
Measure	Dextromethorphan n=14 Participants Participant will take one dextromethorphan 10mg capsule in the morning and at night. Dextromethorphan: (1)10 mg, by mouth, twice daily every 12 hours.	Placebo n=14 Participants Participants will take one placebo capsule in the morning and at night. Placebo: 1 capsule, by mouth, twice daily every 12 hours.
Daily Self-reported Physical Activity	46.92 score/day Standard Deviation 19.79	50.10 score/day Standard Deviation 19.70

SECONDARY outcome

Timeframe: 20 weeks

Population: Scores for the PGIC secondary outcome were not available for analyses due to administrator error. PGIC's were not administered to participants. The PGIC was inadvertently left out of the lab visit packet. Since the PGIC was not administered, data was not collected for both arms/groups.

Patient global impression of change (PGIC) measured on a seven point likert scale (1 = "no change" to 7 = "a great deal better"). PGIC's were not administered to participants. The PGIC was inadvertently left out of the lab visit packet. Since the PGIC was not administered, data was not collected for both arms/groups.

Outcome measures

Outcome data not reported

Adverse Events

Placebo

Serious events: 0 serious events

Other events: 7 other events

Deaths: 0 deaths

Dextromethorphan

Serious events: 0 serious events

Other events: 11 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Additional Information

Dr. Jarred Younger

The University of Alabama at Birmingham

Phone: 2059755821

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	Placebo n=14 participants at risk Participants took one placebo capsule in the morning and one at night for 5 weeks.	Dextromethorphan n=14 participants at risk Participant took one 10 mg dextromethorphan capsule in the morning and one at night for 10 weeks.
Nervous system disorders Anxiety	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.
Gastrointestinal disorders Bloating	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Respiratory, thoracic and mediastinal disorders Chest tightness	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Respiratory, thoracic and mediastinal disorders Cold/respiratory infection	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	0.00% 0/14 • Throughout participants' study completion, 19 weeks.
Gastrointestinal disorders Constipation	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.
Psychiatric disorders Depressed mood	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Gastrointestinal disorders Diarrhea	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.
Infections and infestations Ear infection	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	0.00% 0/14 • Throughout participants' study completion, 19 weeks.
Endocrine disorders Elevated alkaline phosphatase	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.
Endocrine disorders Elevated alanine aminotransferase	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	21.4% 3/14 • Number of events 3 • Throughout participants' study completion, 19 weeks.
Endocrine disorders Elevated chloride	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Eye disorders Eye redness	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Infections and infestations Fever	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	0.00% 0/14 • Throughout participants' study completion, 19 weeks.
Renal and urinary disorders Gallbladder dysfunction	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Gastrointestinal disorders Gastrointestinal upset	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.
Endocrine disorders Hot flashes	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.
Endocrine disorders Low alkaline phosphatase	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	0.00% 0/14 • Throughout participants' study completion, 19 weeks.
Endocrine disorders Low alanine aminotransferase	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Endocrine disorders Low aspartate aminotransferase	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Musculoskeletal and connective tissue disorders Muscle weakness	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	0.00% 0/14 • Throughout participants' study completion, 19 weeks.
Gastrointestinal disorders Nausea	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.
Skin and subcutaneous tissue disorders Rash	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.	0.00% 0/14 • Throughout participants' study completion, 19 weeks.
Infections and infestations Sore throat	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	7.1% 1/14 • Number of events 1 • Throughout participants' study completion, 19 weeks.
Gastrointestinal disorders Vomiting	0.00% 0/14 • Throughout participants' study completion, 19 weeks.	14.3% 2/14 • Number of events 2 • Throughout participants' study completion, 19 weeks.