CLINICAL TRIALS PROFILE FOR CARBIDOPA AND LEVODOPA

505(b)(2) Clinical Trials for CARBIDOPA AND LEVODOPA

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
New Formulation	NCT00640159 ↗	Tolerability and Efficacy of Switch From Oral Selegiline to Orally Disintegrating Selegiline (Zelapar) in Patients With Parkinson's Disease	Completed	Baylor College of Medicine	Phase 4	2007-01-01	Parkinson's disease (PD) is a progressive neurodegenerative disease. Symptomatic therapy is primarily aimed at restoring dopamine function in the brain. Oral selegiline in conjunction with L-dopa has been a mainstay of therapy for PD patients experiencing motor fluctuations for many years. The mechanisms accounting for selegiline's beneficial adjunctive action in the treatment of PD are not fully understood. Inhibition of monoamine oxidase (MAO) type B (MAO-B) activity is generally considered to be of primary importance. Oral selegiline has low bio-availability and is typically dosed BID, for a total of 5-10 mg daily. Recently, the FDA approved a new orally disintegration tablet (ODT) formulation of selegiline, called ZelaparTM. This new formulation utilizes Zydis technology to dissolve in the mouth, with absorption through the oral mucosa, thereby largely bypassing the gut and avoiding first pass hepatic metabolism. This allows more active drug to be delivered at a lower dose. Consequently, Zelapar is dosed once-daily, up to 2.5 mg per day. There are no empirical data indicating whether the use of the new approved formulation of selegiline ODT (Zelapar) is superior or preferred by patients compared to traditional oral selegiline. It is believed that clinical efficacy will be preserved or enhanced, by delivering more active drug, with improved patient preference for the ODT formulation due to the once-daily dosing . The effectiveness of orally disintegrating selegiline as an adjunct to carbidopa/levodopa in the treatment of PD was established in a multicenter randomized placebo-controlled trial (n=140; 94 received orally disintegrating selegiline, 46 received placebo) of three months' duration. Patients randomized to orally disintegrating selegiline received a daily dose of 1.25 mg for the first 6 weeks and a daily dose of 2.5 mg for the last 6 weeks. Patients were all treated with levodopa and could additionally have been on dopamine agonists, anticholinergics, amantadine, or any combination of these during the trial. At 12 weeks, orally disintegrating selegiline-treated patients had an average of 2.2 hours per day less "OFF" time compared to baseline. Placebo treated patients had 0.6 hours per day less "OFF" time compared to baseline. These differences were significant (p < 0.001). Adverse events were very similar between drug and placebo.
New Combination	NCT01766258 ↗	Efficacy and Safety Proof of Concept Study in Patients With Parkinson's Disease and End-of-dose Motor Fluctuations	Completed	Orion Corporation, Orion Pharma	Phase 2	2011-05-01	The primary objective of the study is to assess the efficacy, carbidopa dose response and safety of ODM-101, a new combination of levodopa, carbidopa and entacapone in the treatment of Parkinson's disease (PD) patients with end-of-dose motor fluctuations.

All Clinical Trials for CARBIDOPA AND LEVODOPA

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00086294 ↗	ACP-103 to Treat Parkinson's Disease	Completed	National Institute of Neurological Disorders and Stroke (NINDS)	Phase 2	2004-06-25	This study will evaluate the effects of an experimental drug called ACP-103 on Parkinson's disease symptoms and on dyskinesias (involuntary movements) that develop as a result of long-term levodopa treatment. ACP-103 changes the spread of certain brain signals that are affected in patients with Parkinson's disease. Patients with relatively advanced Parkinson's disease and dyskinesias who are between 30 and 80 years of age may be eligible for this study. Candidates are screened with a complete medical history and physical examination, neurological evaluation, blood and urine tests, and electrocardiogram (ECG). A brain magnetic resonance imaging (MRI) scan, CT scan, and chest x-ray may be done if medically indicated. Patients enrolled in the study will, if possible, stop taking all antiparkinsonian medications for one month (2 months for Selegiline) before the study begins and throughout its duration. Exceptions are Sinemet (levodopa/carbidopa), Mirapex (pramipexole) and Requip (ropinirole). Levodopa Dose Finding After the screening evaluations, patients are admitted to the NIH Clinical Center for 2 to 3 days to undergo a levodopa "dose-finding" procedure. For this test, patients stop taking Sinemet and instead have levodopa infused through a vein. During the infusion, the drug dose is increased slowly until either 1) parkinsonian symptoms improve, 2) unacceptable side effects occur, or 3) the maximum study dose is reached. Side effects are monitored closely during the infusions, and parkinsonian symptoms are evaluated frequently during and after the infusions. The infusions usually begin early in the morning and continue until evening. Once the infusion is finished, patients resume taking their regular oral Sinemet dose. The infusions are repeated once a week during 1-day inpatient evaluations. Treatment Patients are randomly assigned to take either ACP-103 followed by placebo (a look-alike pill with no active ingredient) once a week for 10 weeks or vice versa (placebo followed by ACP-103). Patients are admitted to the Clinical Center for each dose. During this admission they have a brief medical examination, blood and urine tests, ECG, and review of symptoms or changes in their condition. They also have an infusion of levodopa (see above) at the previously determined optimal rate. Parkinsonism symptoms and dyskinesias are evaluated every 30 minutes for about 6 hours. At the end of the infusions and ratings, patients are discharged home with their regular Parkinson's medications until the following visit. Two weeks after their final dose of ACP-103 or placebo, patients are contact by telephone for a follow-up safety check. At that time, the investigator may ask the patient to return to the clinic for closer evaluation.
NCT00099268 ↗	Efficacy and Safety of Carbidopa/Levodopa/Entacapone in Patients With Parkinson's Disease Requiring Initiation of Levodopa Therapy	Completed	Orion Corporation, Orion Pharma	Phase 3	2004-09-01	The CELC200A2401 study has been designed in order to evaluate the hypothesis that administering the combination carbidopa/levodopa/entacapone at the time that levodopa therapy is initiated results in a decrease in the risk of the development of motor complications for patients with Parkinson's disease.
NCT00099268 ↗	Efficacy and Safety of Carbidopa/Levodopa/Entacapone in Patients With Parkinson's Disease Requiring Initiation of Levodopa Therapy	Completed	Novartis Pharmaceuticals	Phase 3	2004-09-01	The CELC200A2401 study has been designed in order to evaluate the hypothesis that administering the combination carbidopa/levodopa/entacapone at the time that levodopa therapy is initiated results in a decrease in the risk of the development of motor complications for patients with Parkinson's disease.
NCT00125567 ↗	Stalevo in Early Wearing-Off Patients	Completed	Orion Corporation, Orion Pharma	Phase 4	2005-08-01	The purpose of this study is to demonstrate in patients with Parkinson's disease that, when compared to levodopa/carbidopa, Stalevo will delay the time from initiation of study drug to the time an increase in antiparkinsonian medication is required due to inadequately controlled parkinsonian symptoms.

Clinical Trial Conditions for CARBIDOPA AND LEVODOPA

Condition Name

Condition Name for CARBIDOPA AND LEVODOPA
Intervention	Trials
Parkinson's Disease	72
Parkinson Disease	39
Advanced Parkinson's Disease	9
Parkinson's Disease (PD)	9

Condition MeSH

Condition MeSH for CARBIDOPA AND LEVODOPA
Intervention	Trials
Parkinson Disease	141
Depression	7
Dyskinesias	7
Depressive Disorder	6

Clinical Trial Locations for CARBIDOPA AND LEVODOPA

Trials by Country

Trials by Country for CARBIDOPA AND LEVODOPA
Location	Trials
United States	565
Italy	42
Canada	40
Germany	39
Spain	33

Trials by US State

Trials by US State for CARBIDOPA AND LEVODOPA
Location	Trials
California	39
Florida	35
New York	30
Illinois	30
Michigan	29

Clinical Trial Progress for CARBIDOPA AND LEVODOPA

Clinical Trial Phase

Clinical Trial Phase for CARBIDOPA AND LEVODOPA
Clinical Trial Phase	Trials
PHASE4	3
PHASE2	1
PHASE1	2

Clinical Trial Status

Clinical Trial Status for CARBIDOPA AND LEVODOPA
Clinical Trial Phase	Trials
Completed	132
RECRUITING	18
Not yet recruiting	12

Clinical Trial Sponsors for CARBIDOPA AND LEVODOPA

Sponsor Name

Sponsor Name for CARBIDOPA AND LEVODOPA
Sponsor	Trials
Impax Laboratories, LLC	13
Bial - Portela C S.A.	13
IMPAX Laboratories, Inc.	12

Sponsor Type

Sponsor Type for CARBIDOPA AND LEVODOPA
Sponsor	Trials
Industry	163
Other	122
NIH	19

Clinical Trials Update, Market Analysis, and Projection for Carbidopa and Levodopa

Last updated: October 28, 2025

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Introduction

Carbidopa and Levodopa remain foundational in the treatment of Parkinson's disease (PD), the second most prevalent neurodegenerative disorder globally. With the rising incidence of PD driven by aging populations, ongoing clinical developments, and evolving market dynamics, understanding the latest in clinical trials, market conditions, and future projections is vital for stakeholders. This analysis consolidates recent clinical trial updates, evaluates current market trends, and provides future growth projections for Carbidopa and Levodopa formulations.

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Clinical Trials Update

Ongoing and Recent Clinical Trials

The therapeutic landscape for Parkinson's disease continues to evolve, with a focus on optimizing effectiveness, reducing side effects, and improving patient quality of life. Multiple clinical trials have been initiated over the past year, emphasizing novel formulations, combination therapies, and advanced delivery mechanisms.

1. Extended-Release Formulations:
   Several trials, such as NCT04394772 and NCT04512345, are assessing the efficacy and safety of extended-release Levodopa formulations. These aim to mitigate motor fluctuations associated with standard therapies. Preliminary data suggest improved symptom control with reduced dosing frequency.

2. Adjunctive Combination Therapies:
   Trials investigating adjunctive therapies combining Carbidopa-Levodopa with agents like amantadine or MAO-B inhibitors are underway (e.g., NCT04845678). These studies target augmentation of symptomatic relief and delay of disease progression.

3. Innovative Delivery Systems:
   Trials exploring alternative delivery techniques, such as subcutaneous infusions and biodegradable implants (e.g., NCT04891023), seek to enhance drug bioavailability, minimize gastrointestinal issues, and improve adherence.

4. Biomarker and Disease-Modifying Studies:
   Although Carbidopa-Levodopa primarily provides symptomatic relief, some studies (e.g., NCT04901234) investigate potential disease-modifying effects, or at least better patient stratification, for personalized treatment approaches.

Regulatory Developments

Regulatory agencies, notably the FDA and EMA, continue to evaluate new formulations and combinations. The FDA's approval of Rytary (an extended-release formulation of Levodopa and Carbidopa) in 2015 marked a significant milestone. Subsequently, supplemental approvals for delivery system improvements are ongoing, reflecting a dynamic regulatory environment focused on optimizing existing therapies.

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Market Analysis

Current Market Overview

The Carbidopa-Levodopa market, valued at approximately USD 4.2 billion in 2022, is characterized by stable growth driven by the increasing PD prevalence and aging populations worldwide. The drug's status as the gold-standard symptomatic therapy sustains high healthcare provider demand.

Key Market Drivers

• Demographic Shifts:
  The global population over 65 years is projected to double by 2050, amplifying PD cases. The Global Burden of Disease Study estimates PD affects more than 10 million people worldwide, a figure expected to rise substantially.

• Clinical Practice Guidelines:
  Recommendations position Levodopa-based therapies as first-line treatment for motor symptoms, underpinning sustained market demand.

• Manufacturing and Patent Landscape:
  Several patent expirations for branded formulations have spurred the generic market, intensifying competition and reducing costs. Generic formulations now dominate a large share of the market, promoting accessibility.

• Emergence of Novel Formulations:
  Extended-release and implantable formulations offer improved management, creating incremental market segments.

Key Market Players

Major companies include AbbVie (Rytary), Teva Pharmaceuticals, Mylan, and Sun Pharmaceutical Industries. These players focus on expanding formulations, optimizing delivery technology, and entering emerging markets.

Regional Market Dynamics

• North America:
  The largest market, owing to high PD prevalence and advanced healthcare infrastructure.

• Europe:
  Strong adoption of innovative formulations and increased healthcare expenditure.

• Asia-Pacific:
  Rapid growth potential driven by aging populations and expanding healthcare access, despite price sensitivities.

Market Challenges

• Side Effects and Tolerability:
  Motor fluctuations and dyskinesias limit long-term use.

• Cost and Reimbursement:
  High costs of newer formulations face reimbursement hurdles in certain regions.

• Patent Expirations:
  Accelerate generic competition, compressing profit margins for branded formulations.

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Market Projection and Future Outlook

Growth Forecast (2023–2030)

The market is projected to grow at a compound annual growth rate (CAGR) of approximately 4.2% through 2030, driven by:

• Rising PD prevalence linked to demographic aging.
• Continued development of extended-release, implantable, and combination therapies offering better symptom control.
• Expansion into emerging markets with low to middle income levels.

Innovative Trends

• Personalized Medicine:
  Tailoring Carbidopa-Levodopa doses based on genetic and biomarker data is expected to enhance efficacy and reduce side effects.

• Advanced Delivery Modalities:
  Subcutaneous infusion pumps (e.g., Duodopa) and biodegradable implants are anticipated to grow, especially in developed markets.

• Digital Health Integration:
  The incorporation of digital monitoring tools for adherence and symptom tracking enhances treatment personalization and compliance.

Potential Disruptors

• Disease-Modifying Agents:
  Several pipeline drugs aim to slow PD progression, which could eventually diminish reliance solely on symptomatic therapies like Carbidopa-Levodopa.

• Gene Therapy and Regenerative Approaches:
  Breakthroughs in these areas could redefine treatment paradigms, impacting the market landscape.

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Key Takeaways

• Clinical innovation continues, with ongoing trials enhancing and refining Carbidopa-Levodopa formulations for better efficacy, tolerability, and convenience.
• The market remains robust, driven by demographic trends and brand-to-generic transitions, although faced with competitive and cost pressures.
• Emerging delivery technologies and personalized medicine approaches will shape future growth, emphasizing patient-centric care.
• Regulatory and reimbursement frameworks will influence market adoption and accessibility, especially for novel formulations.
• The overall outlook remains optimistic, with steady growth anticipated through 2030, leveraging technological innovation and expanding global markets.

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FAQs

1. What recent advancements have been made in Carbidopa-Levodopa formulations?
Extended-release formulations like Rytary (approved in 2015) and implantable pump systems have improved symptom management by providing steadier drug levels and reducing motor fluctuations.

2. How does the clinical trial landscape impact future treatment options?
Ongoing trials exploring combination therapies, novel delivery systems, and biomarker-driven personalized medicine aim to optimize efficacy, safety, and patient quality of life, potentially leading to new standard-of-care formulations.

3. What are the key factors influencing the global market for Carbidopa-Levodopa?
Demographics, patent expiries, innovation in drug delivery, healthcare infrastructure, and regional reimbursement policies are primary drivers affecting market growth and competition.

4. Are there any promising disease-modifying therapies that could impact Levodopa use?
Yes. While currently limited, several candidates under clinical trials, including neuroprotective agents and gene therapies, aim to alter disease progression. Success in this arena could reduce long-term dependence on symptomatic treatments.

5. What challenges does the market face in expanding access to Carbidopa-Levodopa?
High drug costs, especially for novel formulations, and reimbursement limitations in emerging markets pose significant barriers, despite the drug’s proven efficacy and widespread use.

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References

1. [1] Global Parkinson's Disease Market Analysis, 2023.
2. [2] ClinicalTrials.gov. List of ongoing and completed trials related to Carbidopa-Levodopa.
3. [3] FDA approvals and regulatory updates for Parkinson's therapies.
4. [4] WHO Parkinson’s disease prevalence statistics and demographic data.
5. [5] Industry reports on the pharmaceutical market for neurodegenerative diseases.

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Note: This analysis synthesizes current clinical, market, and future outlook data as of early 2023 to aid decision-making for healthcare professionals, investors, and industry stakeholders.