Trial Review

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12619001464156
Ethics application status
Approved
Date submitted
18/09/2019
Date registered
22/10/2019
Date last updated
1/03/2023
Date data sharing statement initially provided
22/10/2019
Date results information initially provided
13/04/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
Do latanoprost eye drops alter optic nerve stress signals in eyes with optic disc drusen?
Scientific title
Latanoprost to alter optic nerve stress signals in eyes with optic disc drusen
Secondary ID [1] 299344 0
Nil known
Universal Trial Number (UTN)
U1111-1240-6078
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Optic disc drusen 314491 0
Condition category
Condition code
Eye 312835 312835 0 0
Diseases / disorders of the eye

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Latanoprost 0.005% eye drops to lower intraocular pressure. These are self administered by participants at home before bedtime once daily in both eyes for a total of one month until retesting (range 25-35 days). Bottles will be collected at completion, but the main test of compliance and efficacy will be a change in intraocular pressure.
Intervention code [1] 315613 0
Treatment: Drugs
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 321443 0
Photopic negative response (PhNR), which is an electroretinogram physiological signal, measured with a hair-thin flexible electrode from the ocular surface using the Diagnosys LLC Color Burst mini-Ganzfeld stimulator, at standardised stimuli, and calculated as the ratio of PhNR to b-wave amplitude, to control for signal strength.
Timepoint [1] 321443 0
Baseline and one month after treatment commencement (range 25-35 days)
Primary outcome [2] 321525 0
Pattern electroretinogram (PERG), which is an electroretinogram physiological signal, measured with a hair-thin flexible electrode from the ocular surface using the Diagnosys LLC Envoy mini-OLED screen stimulator, at standardised checkerboard stimuli, and calculated as the ratio of small checks to large checks to improve specificity of signal.
Timepoint [2] 321525 0
Baseline and one month after treatment commencement (range 25-35 days)
Secondary outcome [1] 375875 0
Intraocular pressure (Goldmann applanation tonometry)
Timepoint [1] 375875 0
Baseline and one month after treatment commencement (range 25-35 days)

Eligibility
Key inclusion criteria
Diagnosed and verifiable optic disc drusen
Willing and able to give consent (parental assent for those under 18)
Baseline intraocular pressure of 15 mmHg or higher in one eye
Minimum age
10 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Inability to attend testing schedule
Allergy to prostaglandin eye drops
Active eye disease requiring treatment, ocular surgery within 6 months
Pregnancy (or possible pregnancy during month of treatment)

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Interventional cohort design, all participants tested before and after treatment
Phase
Phase 4
Type of endpoint/s
Efficacy
Statistical methods / analysis
Power and sample size calculation was performed based on published variance and meaningful differences in the PhNR electrophysiology signal, based on a paired two-group two-tailed comparison. Paired measurements before and after treatment will be recorded from each participant, as well as covariates of visual function and optic nerve structure. The primary outcome can be tested by paired t-test (or non-parametric equivalent), and multivariate regression may be possible.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
4/11/2019
Actual
16/12/2019
Date of last participant enrolment
Anticipated
5/10/2020
Actual
17/07/2020
Date of last data collection
Anticipated
2/11/2020
Actual
14/08/2020
Sample size
Target
16
Accrual to date
Final
23
Recruitment outside Australia
Country [1] 21873 0
New Zealand
State/province [1] 21873 0

Funding & Sponsors
Funding source category [1] 303858 0
University
Name [1] 303858 0
University of Otago Wellington
Country [1] 303858 0
New Zealand
Primary sponsor type
Individual
Name
Jesse Gale
Address
Capital Eye Specialists
Level 2, 148 Cuba St
Wellington 6011
Country
New Zealand
Secondary sponsor category [1] 303996 0
None
Name [1] 303996 0
Address [1] 303996 0
Country [1] 303996 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 304370 0
Health and Disability Ethics Committee (NZ)
Ethics committee address [1] 304370 0
Ministry of Health
Health and Disability Ethics Committees
PO Box 5013
Wellington 6140
Ethics committee country [1] 304370 0
New Zealand
Date submitted for ethics approval [1] 304370 0
27/09/2019
Approval date [1] 304370 0
10/12/2019
Ethics approval number [1] 304370 0
HDEC Ethics ref: 19/CEN/177

Summary
Brief summary
Optic disc drusen (ODD) are common benign calcified deposits in the front of the optic nerve, and some doctors treat them as a type of glaucoma, by lowering the eye pressure, because the progressive visual field defects are similar. This treatment has never been tested because ODD are generally slow-changing. With new electrical recordings we seek to test whether the optic nerve cells are stressed in ODD and whether glaucoma treatment increases or decreases this stress signal.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 96718 0
Dr Jesse Gale
Address 96718 0
Capital Eye Specialists
Level 2, 148 Cuba St
Wellington 6011
Country 96718 0
New Zealand
Phone 96718 0
+64211272979
Fax 96718 0
+6443844937
Email 96718 0
[email protected]
Contact person for public queries
Name 96719 0
Dr Jesse Gale
Address 96719 0
Capital Eye Specialists
Level 2, 148 Cuba St
Wellington 6011
Country 96719 0
New Zealand
Phone 96719 0
+64211272979
Fax 96719 0
+6443844937
Email 96719 0
[email protected]
Contact person for scientific queries
Name 96720 0
Dr Jesse Gale
Address 96720 0
Capital Eye Specialists
Level 2, 148 Cuba St
Wellington 6011
Country 96720 0
New Zealand
Phone 96720 0
+64211272979
Fax 96720 0
+6443844937
Email 96720 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Our anonymised spreadsheet of participant data including extracted metrics from electrophysiology, visual fields, and optical coherence tomography, as well as intraocular pressure, visual acuity and colour vision scores.
When will data be available (start and end dates)?
The data will be available on request from 1 Jan 2021, after all data collection, analysis and writing is complete. Data availability end date to be determined.
Available to whom?
Colleagues and reviewers without conflicts of interest
Available for what types of analyses?
Verification of our findings, we expect that all meaningful analyses will be performed by our investigators, these data are for transparency
How or where can data be obtained?
By email request to the corresponding author, as with supporting documents, [email protected]


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
4939Study protocol  [email protected]
4940Informed consent form  [email protected]
4941Ethical approval  [email protected]



Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
Plain language summaryNo Twenty three people with optic disc drusen partici... [More Details]

Documents added automatically
No additional documents have been identified.