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Vision Response to Dopamine Replacement

This study is currently recruiting participants.
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Verified May 2017 by University of Wisconsin, Madison
Information provided by (Responsible Party):
University of Wisconsin, Madison Identifier:
First received: August 9, 2012
Last updated: May 3, 2017
Last verified: May 2017
The purpose of the study is to evaluate and document physiologic and functional changes in visual performance and retinal function of patients diagnosed with albinism (a dopamine deficiency state) following a trial of oral Levodopa/carbidopa treatment.

Condition Intervention Phase
Albinism Oculocutaneous Albinism Drug: Levodopa/carbidopa Phase 2

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Interventional Study of Levodopa Replacement on Retinal Function in Oculocutaneous Albinism

Resource links provided by NLM:

Further study details as provided by University of Wisconsin, Madison:

Primary Outcome Measures:
  • Visual Acuity Improvement [ Time Frame: 3 months ]
    Change in visual acuity as measured in logMAR by Snellen or Sweep visual evoked potential (SVEP)

Secondary Outcome Measures:
  • Retinal Function [ Time Frame: 3 months ]
    Electroretinography -- electro physiologic testing of retinal function

Other Outcome Measures:
  • Color and Contrast sensitivity [ Time Frame: 3 months ]
    Ancillary testing of visual/retinal function

Estimated Enrollment: 50
Study Start Date: August 2012
Estimated Study Completion Date: October 2017
Estimated Primary Completion Date: September 2017 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Levodopa/carbidopa 4mg/kg/day
Treatment drug taken orally three times daily
Drug: Levodopa/carbidopa
This study will have an intent to treat goal. Anyone that fits the inclusion criteria for the study will be entered and receive study drug.
Other Names:
  • Sinemet
  • Atamet
  • Parcopa

Detailed Description:
In this study the investigators propose that the retina itself in albinism is deficient in dopamine, and vision improvement will occur as a result of improved retinal function in response to the deficient neurotransmitter dopamine. This study has a pretest-posttest design in order to determine if improvement in vision is in response to replacement of deficiency (dopamine). The ERG testing and OCT will be critical determinants to confirm vision improvement as a result of improved retinal function, but are not primary outcome data. Main outcome measures will be collected at pre-treatment, 1 month, 3 months, and 4 months. Change in visual acuity as measured in logMAR by Snellen or SVEP after 3 months of treatment is the primary outcome. Patients include OCA1a patients, OCA1b, OCA2, and unclassified OCA. OCA1a patients clinically are known to have the worst vision, and physiologically have the lowest (or absent) levels of tyrosinase function (Dopamine Production). All patients will be treated with Levodopa/carbidopa 4mg/kg/day in three divided doses.

Ages Eligible for Study:   3 Years and older   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • clinical diagnosis of oculocutaneous albinism
  • age over 3 and weight over 25 lbs.

Exclusion Criteria:

  • ocular only albinism
  • ocular pathology other than albinism
  • neurologic disease, history of myocardial infarction, history of clinical depression, pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01663935

Contact: Michael C Struck, MD 608-263-9859
Contact: Angie Wealti 608-265-7557 Angie Wealti <>

United States, Wisconsin
University of Wisconsin Recruiting
Madison, Wisconsin, United States, 53705
Contact: Angie Wealti    608-265-7557    Angie Wealti <>   
Principal Investigator: Michael C Struck, MD         
Sponsors and Collaborators
University of Wisconsin, Madison
Principal Investigator: Michael C Struck, MD University of Wisconsin, Madison
  More Information

Responsible Party: University of Wisconsin, Madison Identifier: NCT01663935     History of Changes
Other Study ID Numbers: 2016-1576
2012-0023 ( Other Identifier: Study team )
Study First Received: August 9, 2012
Last Updated: May 3, 2017

Keywords provided by University of Wisconsin, Madison:
oculocutaneous albinism
retina function

Additional relevant MeSH terms:
Pigmentation Disorders
Albinism, Oculocutaneous
Eye Diseases, Hereditary
Eye Diseases
Genetic Diseases, Inborn
Amino Acid Metabolism, Inborn Errors
Metabolism, Inborn Errors
Skin Diseases, Genetic
Skin Diseases
Metabolic Diseases
Antiparkinson Agents
Anti-Dyskinesia Agents
Dopamine Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Cardiotonic Agents
Autonomic Agents
Peripheral Nervous System Agents
Protective Agents
Aromatic Amino Acid Decarboxylase Inhibitors
Enzyme Inhibitors processed this record on September 21, 2017