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

September 10, 2025 updated by: Snyder, Robert W., M.D., Ph.D., P.C.

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

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

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

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
35

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

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

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

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

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
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

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Change in Best Corrected Visual Acuity by ETDRS Visual Scale Testing
Time Frame: 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.
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

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Number of Adverse Events Experienced
Time Frame: Monthly for 9 months
Adverse events elicited by nonspecific questioning
Monthly for 9 months
Change in Central Retinal (Macular) Thickness
Time Frame: 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.
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
Time Frame: 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.
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

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Snyder, Robert W., M.D., Ph.D., P.C.

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Snyder Biomedical Corporation

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Robert W Snyder, MD, PhD, Robert W Snyder

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
August 1, 2017

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
July 9, 2020

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
July 9, 2020

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
June 19, 2017

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 21, 2017

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
June 23, 2017

Study Record Updates

Last Update Posted (Estimated)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 12, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 10, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant 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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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