Vision Response to Dopamine Replacement
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.
|Study Design:||Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||Interventional Study of Levodopa Replacement on Retinal Function in Oculocutaneous Albinism|
- Visual Acuity Improvement [ Time Frame: 3 months ] [ Designated as safety issue: No ]Change in visual acuity as measured in logMAR by Snellen or Sweep visual evoked potential (SVEP)
- Retinal Function [ Time Frame: 3 months ] [ Designated as safety issue: No ]Electroretinography -- electro physiologic testing of retinal function
- Color and Contrast sensitivity [ Time Frame: 3 months ] [ Designated as safety issue: No ]Ancillary testing of visual/retinal function
|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)|
Treatment drug taken orally three times daily
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.
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.
|Contact: Michael C Struck, MDfirstname.lastname@example.org|
|Contact: Angie Wealti||608-265-7557||Angie Wealti <email@example.com>|
|United States, Wisconsin|
|University of Wisconsin||Recruiting|
|Madison, Wisconsin, United States, 53705|
|Contact: Angie Wealti 608-265-7557 Angie Wealti <firstname.lastname@example.org>|
|Principal Investigator: Michael C Struck, MD|
|Principal Investigator:||Michael C Struck, MD||University of Wisconsin, Madison|