Clinical Trial: Vision Response to Dopamine Replacement

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional

Official Title: Interventional Study of Levodopa Replacement on Retinal Function in Oculocutaneous Albinism

Brief Summary: 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.

Detailed Summary: 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.
Sponsor: University of Wisconsin, Madison

Current Primary Outcome: Visual Acuity Improvement [ Time Frame: 3 months ]

Change in visual acuity as measured in logMAR by Snellen or Sweep visual evoked potential (SVEP)


Original Primary Outcome: Same as current

Current Secondary Outcome: Retinal Function [ Time Frame: 3 months ]

Electroretinography -- electro physiologic testing of retinal function


Original Secondary Outcome: Same as current

Information By: University of Wisconsin, Madison

Dates:
Date Received: August 9, 2012
Date Started: August 2012
Date Completion: October 2017
Last Updated: May 3, 2017
Last Verified: May 2017