Extension, Carbidopa-levodopa in Neovascular Age-related Macular Degeneration (AMD)

Extension of Protocol 002, Carbidopa-levodopa in Neovascular Extension of Protocol 002, Carbidopa-levodopa in Neovascular AMD

This protocol is an extension of protocol 0002, Proof of Concept and Dose Ranging Study of carbidopa-levodopa in Neovascular AMD. that is a 3 month study of escalating doses of carbidopa-levodopa in neovascular AMD. This trial is a 9 month extension for patients who successfully complete protocol 0002 and wish to continue carbidopa-levodopa therapy. It will use the two higher dose regimens of protocol 0002. these will be assigned according to how well the higher dose was tolerated in protocol 0002.

Study Overview

• Status: Completed
• Conditions: Retina; Macula; Degeneration
• Intervention / Treatment: Drug: carbidopa-levodopa 25-100 mg

Detailed Description

This extension will employ the same medications, measurements, guidelines for anti-VEGF injections and safeguards as in protocol 0002. In combination with protocol 0002, it will provide a total of 12 months of therapy with carbidopa-levodopa.

• Study Type: Interventional
• Enrollment (Actual): 35
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Tucson, Arizona, United States, 85712
      • Robert W Snyder, MD, PhD, PC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Completion of Protocol 002.
2. A diagnosis of AMd with choroidal neovascularization (CNV) in 1 eye.
3. Normal or Dry AMD of any grade in the second eye.
4. Age 50-85 years.
5. Willingness to maintain AREDS vitamin Supplements throughout the study, or remain off of these supplements for the duration of the study, if not taking them prior to the study.
6. Informed consent at visit 1, which is also Visit 5 of study 002.

Exclusion criteria:

1. Any current use of L-DOPA containing medication or dopamine agonist medication, or any planned use of any of these agents, except for study medication, during the study;
2. Concurrent use of monoamine oxidase (MAO) inhibitors;
3. Any eye condition, disease, or history of trauma in either eye, which can impair vision, except cataract or cataract surgery;
4. BCVA worse than 20/60 in the better eye;
5. Wet AMD in the second eye;
6. Neurologic conditions which can impair vision;
7. Parkinson's Disease;
8. Significant orthostatic hypotension, defined as a drop in systolic blood pressure, immediately upon changing from the supine to standing position, of >19 mmHg, or a symptomatic drop in systolic blood pressure, immediately upon changing from the supine to standing position;
9. Significant ECG abnormalities, as judged by the Investigator;
10. Estimated glomerular filtration rate (eGFR) <20 ml/min;
11. Liver enzymes >3 X the upper limit of normal;
12. HbA1C >9.0;
13. Any other significant lab abnormalities, as judged by the Investigator.
14. Women of childbearing potential;
15. Known retinal hemorrhage;
16. Subjects who are not fluent in English.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Carbidopa/levodopa high dose; carbidopa-levodopa 25-100 mg 2 tablets TID	Drug: carbidopa-levodopa 25-100 mg; High Dose: daily oral administration 2 tablets TID Intermediate Dose: daily oral administration 1 tablet TID; Other Names: Sinemet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Best Corrected Visual Acuity by ETDRS Visual Scale Testing	This outcome is a measure of letters correctly identified using an Early Treatment Diabetic Retinopathy Study chart. The higher the number of letters identified, the better the participant's visual acuity.	From the start of the study (Visit 1) to the last completed visit, whether due to patient withdrawal, patient death or the completion of the last visit of the study (visit 12), a maximum of 9 months following a 3 month enrollment in NCT03023059.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Adverse Events Experienced	Adverse events elicited by nonspecific questioning	Monthly for 9 months
Change in Central Retinal (Macular) Thickness	Central retinal thickness (in microns) is measured by spectral domain-optical coherence tomography. An increase in retinal thickness is associated with disease progression. A negative value represents a decrease in retinal thickness and therefore a positive clinical outcome measure.	From the start of the study (Visit 1) to the last completed visit, whether due to patient withdrawal, patient death or the completion of the last visit of the study, a maximum of 9 months.
Percent Change in Retinal Fluid From Baseline	Retinal fluid changes on direct retinal examination on spectral domain - optical coherence tomography. Changes in retinal fluid were compared to baseline values. A negative percentage point represents a decrease in retinal fluid and therefore a positive clinical outcome.	From the start of the study (Visit 1) to the last completed visit, whether due to patient withdrawal, patient death or the completion of the last visit of the study, (visit 10), a maximum of 9 months.

Collaborators and Investigators

• Sponsor: Snyder, Robert W., M.D., Ph.D., P.C.
• Collaborators: Snyder Biomedical Corporation
• Investigators: Principal Investigator: Robert W Snyder, MD, PhD, Robert W Snyder

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2017
• Primary Completion (Actual): July 9, 2020
• Study Completion (Actual): July 9, 2020

Study Registration Dates

• First Submitted: June 19, 2017
• First Submitted That Met QC Criteria: June 21, 2017
• First Posted (Actual): June 23, 2017

Study Record Updates

• Last Update Posted (Estimated): September 12, 2025
• Last Update Submitted That Met QC Criteria: September 10, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Immunologic Factors; Dopamine Agonists; Dopamine Agents; Adjuvants, Immunologic; Antiparkinson Agents; Anti-Dyskinesia Agents; Aromatic Amino Acid Decarboxylase Inhibitors; carbidopa, levodopa drug combination
• Other Study ID Numbers: 0003

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No