CLINICAL TRIALS PROFILE FOR LODOSYN

All Clinical Trials for Lodosyn

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00223717 ↗	Treatment of Supine Hypertension in Autonomic Failure	Completed	Vanderbilt University	Phase 1	2001-01-01	Supine hypertension is a common problem that affects at least 50% of patients with primary autonomic failure. Supine hypertension can be severe, and complicates the treatment of orthostatic hypotension. Drugs used for the treatment of orthostatic hypotension (eg, fludrocortisone and pressor agents), worsen supine hypertension. High blood pressure may also cause target organ damage in this group of patients. The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure have not been defined. In a study, we, the investigators at Vanderbilt University, examined 64 patients with AF, 29 with pure autonomic failure (PAF) and 35 with multiple system atrophy (MSA). 66% of patients had supine systolic (systolic blood pressure [SBP] > 150 mmHg) or diastolic (diastolic blood pressure [DBP] > 90 mmHg) hypertension (average blood pressure [BP]: 179 ± 5/89 ± 3 mmHg in 21 PAF and 175 ± 5/92 ± 3 mmHg in 21 MSA patients). Plasma norepinephrine (92 ± 15 pg/mL) and plasma renin activity (0.3 ± 0.05 ng/mL per hour) were very low in a subset of patients with AF and supine hypertension. (Shannon et al., 1997). Our group has showed that a residual sympathetic function contributes to supine hypertension in patients with severe autonomic failure and that this effect is more prominent in patients with MSA than in those with PAF (Shannon et al., 2000). MSA patients had a marked depressor response to low infusion rates of trimethaphan, a ganglionic blocker; the response in PAF patients was more variable. At 1 mg/min, trimethaphan decreased supine SBP by 67 +/- 8 and 12 +/- 6 mmHg in MSA and PAF patients, respectively (P < 0.0001). MSA patients with supine hypertension also had greater SBP response to oral yohimbine, a central alpha2 receptor blocker, than PAF patients. Plasma norepinephrine decreased in both groups, but heart rate did not change in either group. This result suggests that residual sympathetic activity drives supine hypertension in MSA; in contrast, supine hypertension in PAF. It is hoped that from this study will emerge a complete picture of the supine hypertension of autonomic failure. Understanding the mechanism of this paradoxical hypertension in the setting of profound loss of sympathetic function will improve our approach to the treatment of hypertension in autonomic failure, and it could also contribute to our understanding of hypertension in general.
NCT00223717 ↗	Treatment of Supine Hypertension in Autonomic Failure	Completed	Vanderbilt University Medical Center	Phase 1	2001-01-01	Supine hypertension is a common problem that affects at least 50% of patients with primary autonomic failure. Supine hypertension can be severe, and complicates the treatment of orthostatic hypotension. Drugs used for the treatment of orthostatic hypotension (eg, fludrocortisone and pressor agents), worsen supine hypertension. High blood pressure may also cause target organ damage in this group of patients. The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure have not been defined. In a study, we, the investigators at Vanderbilt University, examined 64 patients with AF, 29 with pure autonomic failure (PAF) and 35 with multiple system atrophy (MSA). 66% of patients had supine systolic (systolic blood pressure [SBP] > 150 mmHg) or diastolic (diastolic blood pressure [DBP] > 90 mmHg) hypertension (average blood pressure [BP]: 179 ± 5/89 ± 3 mmHg in 21 PAF and 175 ± 5/92 ± 3 mmHg in 21 MSA patients). Plasma norepinephrine (92 ± 15 pg/mL) and plasma renin activity (0.3 ± 0.05 ng/mL per hour) were very low in a subset of patients with AF and supine hypertension. (Shannon et al., 1997). Our group has showed that a residual sympathetic function contributes to supine hypertension in patients with severe autonomic failure and that this effect is more prominent in patients with MSA than in those with PAF (Shannon et al., 2000). MSA patients had a marked depressor response to low infusion rates of trimethaphan, a ganglionic blocker; the response in PAF patients was more variable. At 1 mg/min, trimethaphan decreased supine SBP by 67 +/- 8 and 12 +/- 6 mmHg in MSA and PAF patients, respectively (P < 0.0001). MSA patients with supine hypertension also had greater SBP response to oral yohimbine, a central alpha2 receptor blocker, than PAF patients. Plasma norepinephrine decreased in both groups, but heart rate did not change in either group. This result suggests that residual sympathetic activity drives supine hypertension in MSA; in contrast, supine hypertension in PAF. It is hoped that from this study will emerge a complete picture of the supine hypertension of autonomic failure. Understanding the mechanism of this paradoxical hypertension in the setting of profound loss of sympathetic function will improve our approach to the treatment of hypertension in autonomic failure, and it could also contribute to our understanding of hypertension in general.
NCT00547911 ↗	Augmenting Effects of L-DOPS With Carbidopa and Entacapone	Terminated	National Institute of Neurological Disorders and Stroke (NINDS)	Phase 1/Phase 2	2007-10-01	An experimental drug called L-DOPS increases production in the body of a messenger chemical called norepinephrine. Cells in the brain that make norepinephrine are often gone in Parkinson disease. The exact consequences of this loss are unknown, but they may be related to symptoms such as fatigue, depression, or decreased attention that occur commonly in Parkinson disease. This study will explore effects of L-DOPS in conjunction with carbidopa and entacapone, which are drugs used to treat Parkinson disease. We wish to find out what the effects are of increasing norepinephrine production in the brain and whether carbidopa and entacapone augment those effects. Volunteers for this study must be at least 18 years of age and able to give consent to participate in the study. To participate in the study, volunteers must discontinue use of alcohol, tobacco, and certain herbal medicines or dietary supplements, and must also taper or discontinue certain kinds of medications that might interfere with the results of the study. Candidates will be screened with a medical history and physical exam. Participants will be admitted to the National Institutes of Health Clinical Center for two weeks of testing. The study will have three testing phases in a randomly chosen order for each participant: - Single dose of L-DOPS - Single dose of L-DOPS in conjunction with carbidopa - Single dose of L-DOPS in conjunction with entacapone Each phase will last two days, with a washout day between each phase in which no drugs will be given and no testing will be performed. In each phase, participants will undergo a series of tests and measurements, including blood pressure and electrocardiogram tests. Participants who are healthy volunteers will also have blood drawn and will undergo a lumbar puncture (also known as a spinal tap) to obtain spinal fluid for chemical tests.
NCT00581477 ↗	Treatment of Orthostatic Hypotension	Completed	Vanderbilt University	Phase 3	2004-01-01	The purpose of this study is to try different medications in patients with low blood pressure and other problems with their involuntary (autonomic) nervous system. The pharmacological trials in this study will perhaps lead to more effective treatment. This study consists of single dose trials, dose selection trials, 5-day trials and chronic (approximately 2 months) trials.
NCT00581477 ↗	Treatment of Orthostatic Hypotension	Completed	Vanderbilt University Medical Center	Phase 3	2004-01-01	The purpose of this study is to try different medications in patients with low blood pressure and other problems with their involuntary (autonomic) nervous system. The pharmacological trials in this study will perhaps lead to more effective treatment. This study consists of single dose trials, dose selection trials, 5-day trials and chronic (approximately 2 months) trials.

Clinical Trial Conditions for Lodosyn

Condition Name

Condition Name for Lodosyn
Intervention	Trials
Multiple Sclerosis	2
Multiple System Atrophy	2
Autonomic Nervous System Diseases	2
Parkinson Disease	2

Condition MeSH

Condition MeSH for Lodosyn
Intervention	Trials
Primary Dysautonomias	4
Autonomic Nervous System Diseases	4
Parkinson Disease	3
Atrophy	2

Clinical Trial Locations for Lodosyn

Trials by Country

Trials by Country for Lodosyn
Location	Trials
United States	9
United Kingdom	1

Trials by US State

Trials by US State for Lodosyn
Location	Trials
Tennessee	3
Florida	2
New York	1
Michigan	1
Arizona	1

Clinical Trial Progress for Lodosyn

Clinical Trial Phase

Clinical Trial Phase for Lodosyn
Clinical Trial Phase	Trials
Phase 3	2
Phase 2	3
Phase 1/Phase 2	2

Clinical Trial Status

Clinical Trial Status for Lodosyn
Clinical Trial Phase	Trials
Completed	7
Withdrawn	1
Recruiting	1

Clinical Trial Sponsors for Lodosyn

Sponsor Name

Sponsor Name for Lodosyn
Sponsor	Trials
University of Miami	2
Vanderbilt University	2
Vanderbilt University Medical Center	2

Sponsor Type

Sponsor Type for Lodosyn
Sponsor	Trials
Other	11
Industry	2
U.S. Fed	1

Lodosyn Market Analysis and Financial Projection

Last updated: May 1, 2026

Lodosyn (levodopa/benserazide?) Clinical Trial Update and Market Projection

What is Lodosyn and how is it positioned commercially?

Lodosyn is the brand name for carbidopa (marketed in the US as carbidopa tablets), used in combination with levodopa for Parkinson’s disease. In practice, Lodosyn is used to reduce peripheral dopamine-related side effects of levodopa and improve tolerability, while enabling higher effective levodopa dosing in the central nervous system.

Commercial positioning (high level):

• Drug class: Dopamine decarboxylase inhibitor used with levodopa.
• Use case: Parkinson’s disease (as an add-on component to levodopa regimens).
• Competitive set: Generic carbidopa products and fixed-dose combinations containing carbidopa with levodopa (where applicable by formulation and dosing).

Market implications:

• A standalone branded product in a largely mature, genericized class typically faces pricing pressure, low incremental clinical differentiation, and limited late-stage trial activity unless new indications or novel formulations emerge.
• Any market growth trend usually comes from volume stability, mix shifts (dose form and adherence), and regional competitive dynamics, not from new efficacy breakthroughs.

What does the clinical pipeline look like for Lodosyn now?

Lodosyn (carbidopa) has a mature clinical profile. Carbidopa is an established therapy with decades of clinical use, which typically results in:

• Minimal phase 3 or registrational “new drug” activity for the molecule itself.
• More common activity in the category is bioequivalence, formulation changes, label maintenance, and post-approval safety/real-world evidence rather than new efficacy pathways.

Clinical trial update (practical market signal):

• For a mature active pharmaceutical ingredient like carbidopa, the most relevant “trial activity” for business and investment purposes is usually regulatory submissions and bioequivalence studies for generics rather than new mechanistic development for Lodosyn itself.
• Without evidence of a current phase 3 or phase 2 efficacy program tied to Lodosyn (carbidopa) as a differentiated product, the pipeline signal for market expansion is generally weak.

What is the current market structure for carbidopa-containing Parkinson regimens?

Competitive drivers

For Lodosyn-like products (carbidopa):

• Generic penetration compresses branded pricing.
• Formulation and dosing flexibility matters because neurologists titrate levodopa/carbidopa regimens across patient subgroups.
• Fixed-dose combination products can reduce demand for separate carbidopa add-on tablets depending on local prescribing norms and payer formularies.

Key demand constraints

• Parkinson’s disease prevalence grows over time, but carbidopa’s market growth is typically slower than prevalence growth because it is often substituted within class (generic interchange) and because many patients are maintained on established levodopa/carbidopa titration regimens.

How should businesses project the Lodosyn/carbidopa market going forward?

Projection framework

Because carbidopa is mature and generally genericized, a credible forward model uses three levers:

1. Total treated Parkinson volume (trend anchored to prevalence and treatment rates).
2. Share of regimen type that uses standalone carbidopa versus fixed-dose combinations.
3. Pricing and reimbursement (brand share erosion, generic price levels, tender effects).

Projection direction (directional, not speculative)

• Base case: modest growth in units aligned to Parkinson treatment volumes, offset by ongoing brand share erosion and pricing pressure.
• Downside: continued generic substitution and payer formulary tightening reduce net revenue per tablet.
• Upside: if there is evidence of branded retention via specialty channel contracts or if formulations improve adherence, but such upside typically requires demonstrated differentiation.

Investment-grade conclusion

Absent evidence of a fresh registrational clinical program or a differentiated formulation with meaningful clinical advantages, the market is best treated as a mature, volume-driven segment with low pricing elasticity and high generic substitution risk.

What filings and regulatory activity typically matter for Lodosyn?

For mature products like carbidopa brands, the business-critical “activity” usually appears as:

• ANDAs and bioequivalence for generic carbidopa.
• Label updates (safety communications, updated wording).
• Formulation changes (release profile, tablet strength adjustments).

For market sizing and forecast accuracy, those activities affect:

• Competitor count
• Formulary access
• Net price realization by channel

So what is the actionable takeaway for R&D and investment?

Decision-grade assessment

• R&D posture: A molecule-level “new trial” strategy for carbidopa is unlikely to generate late-stage value unless paired with a genuinely differentiated mechanism, formulation breakthrough, or new indication with a clear clinical endpoint package.
• Commercial posture: Expect continued branding pressure. Execution priority typically shifts to channel management, contracting, and defensive lifecycle management (product supply reliability and dosing coverage).
• Market view: Treat Lodosyn as a mature Parkinson support therapy where growth depends on Parkinson patient volume and regimen mix, not on late-stage innovation.

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Key Takeaways

• Lodosyn is carbidopa, used with levodopa in Parkinson’s disease to improve tolerability and enable dosing.
• Clinical development is typically mature for carbidopa, with most activity in bioequivalence/formulation and regulatory maintenance rather than new efficacy trials.
• Market growth is volume- and mix-driven and faces persistent generic substitution and pricing pressure.
• For investment and R&D, pipeline-based upside is limited unless a differentiated product concept or new clinical indication is established.

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FAQs

1) Is Lodosyn considered a new molecular entity with an active phase 3 program?

No. Lodosyn (carbidopa) is established, and clinical activity for this class is typically non-registrational (bioequivalence, formulation, label maintenance) rather than phase 3 efficacy development.

2) What is the main driver of Lodosyn demand?

The number of Parkinson’s patients treated with levodopa/carbidopa regimens and dosing titration practices that use standalone carbidopa versus fixed-dose combinations.

3) What market risk most affects Lodosyn revenue?

Generic substitution and pricing compression as payer formularies and competitive tendering favor lower-cost equivalents.

4) Does Lodosyn have differentiation beyond tolerability and regimen optimization?

The clinical value is largely tied to its role in levodopa therapy tolerability and regimen flexibility, with differentiation difficult in a mature molecule without a novel formulation or new indication.

5) How should projections be modeled for a mature carbidopa brand?

Use prevalence and treated population trends, estimate regimen mix (standalone versus fixed-dose), then apply net price assumptions that reflect generic penetration and channel contracting.

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References

[1] FDA. Drug Approval Reports for carbidopa/levodopa products and labeling databases (accessed via FDA drug labels and approval histories).
[2] ClinicalTrials.gov. Studies for carbidopa and related Parkinson’s regimen components (accessed via database query for carbidopa).
[3] EMA. Public assessment reports and product information for carbidopa-containing therapies (accessed via EMA product and EPAR resources).