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SuspendedNCT04000919Updated Oct 17, 2022

Effects of 5HTP and LDOPA on CNS Excitability After SCI

A Phase 2/3 interventional study of 5HTP and L-DOPA in Spinal Cord Injuries, sponsored by Jessica M D'Amico. Suspended at 1 site in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2022-10-17.

Sponsored by Jessica M D'Amico · Phase 2/3, Interventional, and Basic science

Why this study was suspended
PI left UofL and intends to reopen study at University of Alberta
Phase
Phase 2/3
Study type
Interventional
Enrollment
30
Allocation
Randomized
Ages
18 Years to 65 Years
Sex
All
01

Study summary

This study will examine whether supplementation with the serotonin and dopamine precursors, 5HTP and L-DOPA can alter central nervous system excitability and improve motor function after incomplete and complete spinal cord injuries.

02

Conditions studied

  • Spinal Cord Injuries
03

In context

Spinal Cord Injuries

1,948 studies on the registry are indexed under Spinal Cord Injuries; 505 are open to participants now.

This study's planned enrollment of 30 is above the median of 24 across 1,566 interventional studies indexed under Spinal Cord Injuries.

Browse Spinal Cord Injuries studies →

Lead sponsor

This is the only study on the registry with Jessica M D'Amico as lead sponsor.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Individuals aged 18-65 years of age.
  • Patients must have suffered a trauma to the spinal cord at least 1 year ago or longer.
  • Patients must exhibit some degree of spasticity which can be self-reported (Penn spasm frequency) or if assessed by a physiotherapist, a modified Ashworth spasticity score greater than 1

Exclusion criteria

Exclusion Criteria:

  • Individuals with damage to the nervous system other than to the spinal cord
  • Pregnant or breastfeeding women
  • Alcoholic patients
  • Patients with a history of seizures or epilepsy
  • Patients with a history of suicidal thoughts or behaviors
  • Patients with active or inactive implants including cardiac pacemakers, implantable defibrillators, ocular implants, deep brain stimulators, vagus nerve stimulator, and implanted medication pumps
  • Patients with conductive, ferromagnetic or other magnetic-sensitive metals implanted in their head
  • Patients with:
  • Known or suspected allergy to the medication or the ingredients
  • Cardiovascular disease including history of heart attack or heart rhythm irregularities
  • Coronary artery disease
  • Comatose or depressed states due to CNS depressants
  • Endocrine dysfunction
  • Blood dyscrasias
  • Bone marrow depression
  • History of seizures
  • Hypocalcemia
  • History of stomach ulcers
  • Wide-angle glaucoma
  • Phenylketonuria

Patients taking:

  • Monoamine oxidase inhibitor therapy
  • Serotonergic antidepressants: selective serotonin and norepinephrine reuptake inhibitors
  • Tricyclic antidepressants
  • Any type of serotonergic agonist
  • Dopamine D2 receptor antagonists
  • Amphetamine
  • CNS depressants
  • Levodopa
  • Lithium
  • Anti-hypertensive drugs (Carbidopa and L-DOPA)
  • Iron salts
  • Metoclopramide
  • Phenothiazine medication
05

Study design

Phase
Phase 2 / Phase 3
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Double (Participant, Outcomes assessor)
Enrollment
30 participants (estimated)

Study arms

  • Sham comparator
    Effects of single-dose of carbidopa (50mg) on CNS excitability

    Participants will visit the lab and on one of four different occasions they will receive carbidopa only (50 mg). Neurophysiology outcome measures will be obtained at 30, 60, 90, 120 and 150 min post drug-intake.

    Drug: Carbidopa

  • Placebo comparator
    Effects of single-dose placebo on CNS Excitability

    Participants will visit the lab and on one of four different occasions and will receive a placebo. Neurophysiology outcome measures will be obtained at 30, 60, 90, 120 and 150 min post drug-intake.

    Drug: Placebo oral tablet

  • Active comparator
    Effects of single-dose 5HTP/carbidopa on CNS Excitability

    During one of the four occasions participants visit the lab they will receive 5HTP combined with carbidopa (50-200mg HTP/50mg carbidopa). Neurophysiology outcome measures will be obtained at 30, 60, 90, 120 and 150 min post drug-intake.

    Drug: 5HTP

  • Active comparator
    Effects of single-dose L-DOPA/carbidopa on CNS Excitability

    During one of the four occasions participants visit the lab they will receive L-DOPA combined with carbidopa (50-200mg L-DOPA/50mg carbidopa). Neurophysiology outcome measures will be obtained at 30, 60, 90, 120 and 150 min post drug-intake.

    Drug: L-DOPA

Interventions

  • Drug5HTP

    5HTP/carbidopa (50-200 mg 5-HTP/50 mg carbidopa)

    Also known as: carbidopa

  • DrugL-DOPA

    L-DOPA/carbidopa (50-200 mg L-DOPA/50 mg carbidopa)

    Also known as: Sinemet, Carbidopa

  • DrugPlacebo oral tablet

    Placebo

  • DrugCarbidopa

    Carbidopa (50mg)

06

What researchers measure

Primary outcomes

  1. Change in corticospinal excitability

    Transcranial magnetic stimulation motor-evoked potentials

    Time frame: Pre drug-intake, 30minutes, 60minutes, 90minutes, 120minutes post drug-intake

  2. Change in motoneuron excitability

    F waves

    Time frame: Pre drug-intake, 30minutes, 60minutes, 90minutes, 120minutes post drug-intake

  3. Change in spinal excitability

    H reflex

    Time frame: Pre drug-intake, 30minutes, 60minutes, 90minutes, 120minutes post drug-intake

  4. Change in spasticity

    Cutaneomuscular reflex

    Time frame: Pre drug-intake, 30minutes, 60minutes, 90minutes, 120minutes post drug-intake

  5. Change in movement performance

    Leg cycling

    Time frame: Pre drug-intake, 120-150minutes post drug-intake

Secondary outcomes

  1. Serum Analysis 5-HIAA

    5-HIAA (serum)

    Time frame: 90-120minutes post drug-intake

  2. Serum Analysis 5-HT

    5-HT (serum)

    Time frame: 90-120minutes post drug-intake

  3. Whole blood analysis 5-HT

    5-HT (whole blood)

    Time frame: 90-120minutes post drug-intake

  4. Serum analysis Cortisol

    Cortisol level

    Time frame: 90-120minutes post drug-intake

  5. Serum and Urine Analysis of dopamine

    catecholamines and homovanillic acid (urine)

    Time frame: 90-120min post drug-intake

  6. Serum Catechloamines

    catecholamines and homovanillic acid (urine)

    Time frame: 90-120minutes post drug-intake

  7. Urine Homovanillic acid

    homovanillic acid (urine)

    Time frame: 90-120minutes post drug-intake

07

Study locations

1 site
  • University of Louisville, Kentucky Spinal Cord Injury Research Centre
    Louisville, Kentucky 40202, United States
08

References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Oct 17, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04000919
Lead sponsor
Jessica M D'Amico
Responsible party
Jessica M D'Amico (Assistant Professor, University of Louisville) — Sponsor-investigator
First posted
Jun 27, 2019
Start date
Jun 19, 2019
Primary completion
Jun 30, 2023 (estimated)
Completion
Dec 30, 2023 (estimated)
Last update
Oct 17, 2022

Study contacts

Jessica D'Amico, PhD
principal investigator · University of Louisville

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is suspended, as verified in Oct 2022. You cannot join it, but the record below documents what was studied.

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