A Phase 2 interventional study of Dextromethorphan in Central Neuropathic Pain, Allodynia and Spinal Cord Injury, sponsored by Brigham and Women's Hospital. Completed at 1 site in United States. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2025-12-08.
Sponsored by Brigham and Women's Hospital · Phase 2, Interventional, and Treatment
This randomized, placebo-controlled, double-blind 4x4 crossover clinical trial was part of a larger NIH-funded study to evaluate the analgesic efficacy of three doses of chronic oral (PO) dextromethorphan compared to placebo in central neuropathic pain following spinal cord injury. Subjects' maximally tolerated doses (MTD) were first determined to establish individual dose-analgesic response relationships in a run-in period; following a washout period, subjects were then randomized to receive an order of four doses of dextromethorphan (including placebo) in a 4x4 Latin square cross-over design.
166 studies on the registry are indexed under Hyperalgesia; 14 are open to participants now.
This study's enrollment of 26 is below the median of 50 across 142 interventional studies indexed under Hyperalgesia.
Browse Hyperalgesia studies →Brigham and Women's Hospital is the lead sponsor of 1,267 studies on the registry; 228 are open to participants now.
Of its 116 completed or terminated interventional studies of FDA-regulated products, 65 (56%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Serum laboratory examination obtained at study entry:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CYP3A (CYP3A4) inhibitors and inducers
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
0% MTD Dextromethorphan
Drug: Dextromethorphan
25% MTD Dextromethorphan
Drug: Dextromethorphan
50% MTD Dextromethorphan
Drug: Dextromethorphan
100% MTD Dextromethorphan
Drug: Dextromethorphan
0, 25, 50 and 100% of maximum tolerated dose, each administered over a 4 week period
Mean Pain Intensity (Percent Change From Baseline)
Primary outcome was percent change from baseline in mean pain intensity (transformed Gracely Scale; 0-35). Baseline was defined as the week prior to randomization. The greater the percent change, the bigger the reduction in pain intensity.
Time frame: 1st week of maintenance period (week prior to hospital admission for nested study; subjects traveled to Boston on days 6-7 of the maintenance period)
Satisfaction
Satisfaction with study treatment assessed over the 7 days prior to admission (5-point categorical scale)
Time frame: Last week prior to admission (end of 1-week maintenance period)
Subjects were recruited nationally from referring physicians, through advertisements, and through existing databases.
| Milestone | Dextromethorphan Dose Response (DDR) Clinical Trial |
|---|---|
| Started | 26 |
| 0% mtd | 25 |
| 25% mtd | 26 |
| 50% mtd | 25 |
| 100% mtd | 25 |
| Completed | 25 |
| Not completed | 1 |
| Withdrew: Withdrawal by subject | 1 |
Primary outcome was percent change from baseline in mean pain intensity (transformed Gracely Scale; 0-35). Baseline was defined as the week prior to randomization. The greater the percent change, the bigger the reduction in pain intensity.
| Percent change from baseline | 0% MTD Dex | 25% MTD Dex | 50% MTD Dex | 100% MTD Dex |
|---|---|---|---|---|
| Mean Pain Intensity (Percent Change From Baseline) | -0.006 ± 0.01 | -0.018 ± 0.005 | -0.073 ± 0.01 | -0.24 ± 0.01 |
Satisfaction with study treatment assessed over the 7 days prior to admission (5-point categorical scale)
| Participants | 0% MTD Dex | 25% MTD Dex | 50% MTD Dex | 100% MTD Dex |
|---|---|---|---|---|
| Not Satisfied | 20 | 18 | 16 | 9 |
| Fairly Satisfied | 2 | 5 | 7 | 8 |
| Satisfied | 3 | 2 | 0 | 5 |
| Very/Extremely Satisfied | 0 | 1 | 2 | 3 |
Collected over Adverse event data were collected post-dose through the end of treatment in each arm.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| 0% MTD Dex | — | 0/25 (0%) | 2/25 (8%) |
| 25% MTD Dex | — | 0/26 (0%) | 3/26 (11.5%) |
| 50% MTD Dex | — | 0/25 (0%) | 2/25 (8%) |
| 100% MTD Dex | — | 0/25 (0%) | 16/25 (64%) |
| Event | 0% MTD Dex | 25% MTD Dex | 50% MTD Dex | 100% MTD Dex |
|---|---|---|---|---|
| SedationNervous system disorders | 0/25 | 0/26 | 0/25 | 8/25 |
| Blurry VisionNervous system disorders | 0/25 | 0/26 | 0/25 | 3/25 |
| Interference with AlertnessNervous system disorders | 2/25 | 3/26 | 0/25 | 3/25 |
| TinnitisEar and labyrinth disorders | 0/25 | 0/26 | 2/25 | 0/25 |
| Interference with Ability to DriveNervous system disorders | 0/25 | 0/26 | 0/25 | 2/25 |
| Age, Categorical(Participants) | Dextromethorphan Dose Response Clinical Trial |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 25 |
| >=65 years | 1 |
| Age, Continuous(years) | Dextromethorphan Dose Response Clinical Trial |
|---|---|
| Mean | 46.84 ± 11.32 |
| Sex: Female, Male(Participants) | Dextromethorphan Dose Response Clinical Trial |
|---|---|
| Female | 14 |
| Male | 12 |
| Region of Enrollment(participants) | Dextromethorphan Dose Response Clinical Trial |
|---|---|
| North America | 26 |
This study is completed, as verified in Nov 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Dextromethorphan
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