Effects of 5HTP and LDOPA on CNS Excitability After SCI

Jessica M D'Amico

Status and phase: Suspended; Phase 3; Phase 2

Conditions: Spinal Cord Injuries

Treatments: Drug: Placebo oral tablet; Drug: Carbidopa; Drug: 5HTP; Drug: L-DOPA

Study type: Interventional

Funder types: Other

Identifiers

NCT04000919

18.1268

Details and patient eligibility

About

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.

Enrollment: 30 estimated patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

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

• 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

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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30 participants in 4 patient groups, including a placebo group

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

Sham Comparator group

Description:

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.

Treatment:

Drug: Carbidopa

Effects of single-dose placebo on CNS Excitability

Placebo Comparator group

Description:

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.

Treatment:

Drug: Placebo oral tablet

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

Active Comparator group

Description:

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.

Treatment:

Drug: 5HTP

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

Active Comparator group

Description:

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.

Treatment:

Drug: L-DOPA