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placebo/L-dopa
placebo/L-dopa is a Dopamine precursor / Antiparkinson agent Small molecule drug developed by GlaxoSmithKline. It is currently FDA-approved for Parkinson's disease motor symptoms, Restless legs syndrome (off-label).
L-dopa is a precursor to dopamine that crosses the blood-brain barrier and is converted to dopamine to replenish depleted dopamine levels in Parkinson's disease.
L-dopa is used to treat conditions such as Parkinson Disease, Movement Disorders, and Neurodegenerative Diseases, as indicated by ClinicalTrials.gov. Placebo is used as a control in studies comparing its effects to those of L-dopa, such as in the study "Dyskinesia in Parkinson's Disease (Study P04501)" on ClinicalTrials.gov.
At a glance
| Generic name | placebo/L-dopa |
|---|---|
| Sponsor | GlaxoSmithKline |
| Drug class | Dopamine precursor / Antiparkinson agent |
| Target | Dopamine (via conversion by aromatic amino acid decarboxylase) |
| Modality | Small molecule |
| Therapeutic area | Neurology |
| Phase | FDA-approved |
Mechanism of action
L-dopa (levodopa) is an amino acid that penetrates the blood-brain barrier more effectively than dopamine itself. Once in the brain, the enzyme aromatic amino acid decarboxylase converts L-dopa to dopamine, restoring neurotransmitter levels in patients with Parkinson's disease where dopamine-producing neurons have degenerated. It is typically co-administered with carbidopa or benserazide (decarboxylase inhibitors) to prevent peripheral conversion and improve central nervous system delivery.
Approved indications
- Parkinson's disease motor symptoms
- Restless legs syndrome (off-label)
Common side effects
- Nausea
- Dyskinesia
- Orthostatic hypotension
- Dizziness
- Hallucinations
- Confusion
- On-off fluctuations
Key clinical trials
- Dopamine Modulation of Motivation and Motor Function in Major Depression & Inflammation (NA)
- Dopaminergic Dysfunction in Late-Life Depression (PHASE2)
- Dopaminergic Therapy for Anhedonia - 2 (PHASE4)
- A Targeted Amino Acid Supplement for People With Parkinson's Disease (EARLY_PHASE1)
- Droxidopa to Increase Mean Arterial Pressure in Decompensated Cirrhosis Patients With Acute Kidney Injury (PHASE2)
- OpiCapone Effect on Motor Fluctuations and pAiN (PHASE4)
- Early ParkinSon wIth L-DOPA/DDCI and OpicapoNe (EPSILON Study) (PHASE3)
- REALITY MONITORING (NA)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- placebo/L-dopa CI brief — competitive landscape report
- placebo/L-dopa updates RSS · CI watch RSS
- GlaxoSmithKline portfolio CI
Frequently asked questions about placebo/L-dopa
What is placebo/L-dopa?
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Related
- Drug class: All Dopamine precursor / Antiparkinson agent drugs
- Target: All drugs targeting Dopamine (via conversion by aromatic amino acid decarboxylase)
- Manufacturer: GlaxoSmithKline — full pipeline
- Therapeutic area: All drugs in Neurology
- Indication: Drugs for Parkinson's disease motor symptoms
- Indication: Drugs for Restless legs syndrome (off-label)
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing