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Trial registered on ANZCTR


Registration number
ACTRN12611000669998
Ethics application status
Approved
Date submitted
29/06/2011
Date registered
4/07/2011
Date last updated
23/11/2015
Type of registration
Prospectively registered

Titles & IDs
Public title
Combining selective serotonin reuptake inhibitors and patching to improve visual function in adult amblyopia (“Lazy Eye”)
Scientific title
In adult patients with amblyopia, is citalopram combined with part time monocular occlusion more effective than monocular occlusion alone in improving visual acuity in the amblyopic eye?
Secondary ID [1] 262531 0
Nil
Universal Trial Number (UTN)
U1111-1122-4973
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Amblyopia 268199 0
Condition category
Condition code
Eye 268327 268327 0 0
Diseases / disorders of the eye

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Citalopram, 20mg per day for 2 weeks combined with monocular occlusion of the amblyopic eye, 2 hours per day for 2 weeks. Monocular occlusion involves wearing an opaque eye patch over the non-amblyopic eye. Citalopram will be administered in oral tablet form. This study will adopt a cross-over design with placebo and drug arms separated by a 2-week washout period.
Intervention code [1] 266876 0
Treatment: Drugs
Comparator / control treatment
Placebo combined with monocular occlusion of the amblyopic eye, 2 hours per day for 2 weeks. This study will adopt a cross-over design with placebo and drug arms separated by a 2-week washout period. The placebo wil be made of methlycellulose in a gelatin capsule.
Control group
Placebo

Outcomes
Primary outcome [1] 269099 0
Visual acuity in the amblyopic eye measured using a LogMAR eye chart
Timepoint [1] 269099 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [1] 276924 0
Amplitude and/or latency of the amblyopic eye pattern reversal visual evoked potential
Timepoint [1] 276924 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [2] 276925 0
Amplitude and/or latency of the amblyopic eye multifocal electroretinogram
Timepoint [2] 276925 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [3] 276926 0
Stereoscopic depth perception measured using the Randot Test, the Frisby test and the TNO test (TNO is the official name of this test rather than an abbreviation).
Timepoint [3] 276926 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [4] 276927 0
Suppression measured using the Worth 4 Lights test and the Bagolini Striated Lenses test
Timepoint [4] 276927 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [5] 276928 0
Motor cortex excitability measured using transcranial magnetic stimulation and motor evoked potentials
Timepoint [5] 276928 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [6] 276929 0
Motor cortex plasticity measured using the paired associative stimulation technique that involves transcranial magnetic stimulation, electrical nerve stimulation and motor evoked potentials
Timepoint [6] 276929 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [7] 276930 0
Heart rate variability. Heart rate will be measured using a standard Polar chest strap and watch. This chest strap is a heart rate monitor that is fitted around the participant's chest, so that it is in contact with their skin. The watch is worn by the researcher and is connected with the polar chest strap, displaying the participant's heart rate and recording the hart rate data. The participant's heart rate data will be downloaded to a computer for subsequent calculation and analysis of heart rate variability (HRV). The analysis of HRV will utilise a method called frequency domain analysis, which is based on the theory that the parasympathetic and sympathetic systems of the autonomic nervious system modulate heart rate intervals at specific frequencies. Essentially, the parasympathetic activity is linked to a fast, high frequency range while sympathetic activity is associated with a low frequency range. HRV information can be gained by analysing the fluctuations in frequency.
Timepoint [7] 276930 0
Baseline measurements upon participant recruitment, directly before the first 2 weeks of occlusion, directly after the first 2weeks of occlusion, at the end of the 2 week washout period which is also directly before the second 2 weeks of occlusion, directly after the second 2 weeks of occlusion and 2 weeks after the second 2 weeks of occlusion (second washout period).
Secondary outcome [8] 276931 0
Blood tests for brain derived neurotrophic factor genotype and 5-HT transporter genotype as well as blood levels of citalopram
Timepoint [8] 276931 0
Directly after each 2 week session of monocular occlusion

Eligibility
Key inclusion criteria
Monocular amblyopia
No ocular pathology
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
A personal history, or family history, of mood disorder such as depression or bipolar disorder, diabetes, a history of drug, alcohol or nicotine addiction, taking medications or supplements known to alter moods such as St John’s Wort, taking medications which affect SSRIs, such as codeine (coughing, pain killer medication), being a postgraduate student supervised by one of the researchers involved in this study.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Potential participants will self-identify, by responding to advertisements, posters, flyers, newspaper advertisements and web-based recruitment (such as getparticipants.com). Participants may also be provided with a participant information sheet or given the contact details of the researchers by their optometrist. If screening indicates that the participant is eligible all researchers who have responsibility for data collection will be blinded to whether the participant receives placebo tablets in the first or second 2-week periods of monocular occlusion. The tablets are prepared and supplied in unmarked blister packs by a pharmacist involved in the study who has no contact with the participants. Allocation will be by concealment using central randomization by computer.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Custom computer software will be used to randomize participants into the drug first or drug second groups. This software takes into account the ages and genders of participants already allocated to each group before making an allocation.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/10/2011
Actual
16/09/2011
Date of last participant enrolment
Anticipated
Actual
2/12/2013
Date of last data collection
Anticipated
Actual
Sample size
Target
20
Accrual to date
Final
7
Recruitment outside Australia
Country [1] 3680 0
New Zealand
State/province [1] 3680 0
Auckland

Funding & Sponsors
Funding source category [1] 267348 0
Government body
Name [1] 267348 0
The Marsden Fund
Country [1] 267348 0
New Zealand
Primary sponsor type
University
Name
The University of Auckland
Address
The University of Auckland
Private Bag 90210
Auckland
Country
New Zealand
Secondary sponsor category [1] 266414 0
None
Name [1] 266414 0
Address [1] 266414 0
Country [1] 266414 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 269325 0
The Northern X Regional Ethics Commitee
Ethics committee address [1] 269325 0
3rd floor, Unisys building
650 Great South Rd
Penrose
Private Bag 92-522, Wellesley St
Auckland
Ethics committee country [1] 269325 0
New Zealand
Date submitted for ethics approval [1] 269325 0
Approval date [1] 269325 0
14/06/2011
Ethics approval number [1] 269325 0
NTX/11/06/044

Summary
Brief summary
Amblyopia, or ‘lazy eye’, is a developmental disorder of the visual cortex. An effective treatment for amblyopia in children is patching the healthy eye to encourage use of the amblyopic eye; however this treatment is not effective in adults because the adult brain does not have sufficient capacity for change, a property known as neural plasticity. Neural plasticity is the process by which connections between neurons in the brain are formed and strengthened by new experiences, and is an essential component of learning and memory. Recent studies have shown that anti-depressant drugs are capable of reinstating plasticity in the adult brain. This study will determine whether the anti-depressant drug Citalopram will restore sufficient plasticity within the adult brain to allow for short-term patching (2 hours per day for two weeks) to improve visual function in adults with amblyopia.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 32813 0
A/Prof Benjamin Thompson
Address 32813 0
Department of Optometry and Vision Science
University of Auckland
Auckland
New Zealand
1142
Country 32813 0
New Zealand
Phone 32813 0
+64 9 5236020
Fax 32813 0
Email 32813 0
b.thompson@auckland.ac.nz
Contact person for public queries
Name 16060 0
Benjamin Thompson
Address 16060 0
Department of Optometry and Vision Science
University of Auckland
Private Bag 92019
Auckland
1142
Country 16060 0
New Zealand
Phone 16060 0
+64 9 923 6020
Fax 16060 0
Email 16060 0
b.thompson@auckland.ac.nz
Contact person for scientific queries
Name 6988 0
Benjamin Thompson
Address 6988 0
Department of Optometry and Vision Science
University of Auckland
Private Bag 92019
Auckland
1142
Country 6988 0
New Zealand
Phone 6988 0
+64 9 923 6020
Fax 6988 0
Email 6988 0
b.thompson@auckland.ac.nz

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseAdvances in Amblyopia Treatment: Paradigm Shifts and Future Directions.2017https://dx.doi.org/10.1097/IIO.0000000000000184
EmbaseThe effect of combined patching and citalopram on visual acuity in adults with amblyopia: A randomized, crossover, placebo-controlled trial.2019https://dx.doi.org/10.1155/2019/5857243
N.B. These documents automatically identified may not have been verified by the study sponsor.