Subthreshold Nanosecond Laser for Non-resolving Central Serous Chorioretinopathy (NANO-C)

Subthreshold Nanosecond Laser for Non-resolving Central Serous Chorioretinopathy: A Double-masked Sham-controlled Randomised Trial

This is a prospective, multicentre, sham-controlled, participant- and assessor-masked superiority trial with two parallel treatment arms which aims to investigate the safety and efficacy of subthreshold nanosecond laser (SNL) in a series of adults with sub-retinal fluid secondary to non-resolving central serous chorioretinopathy (CSCR) by visual and anatomical outcomes.

The study population will be individuals with adults (aged 18-70 years inclusive) with non-resolving CSCR (defined as CSCR present for a duration of more than 3 months presenting with either focal or diffuse leakage) who meet all eligibility criteria.

60 subjects total will be enrolled into the study - 40 randomized to receive SNL treatment and 20 to receive sham treatment as per a 2:1 randomization schedule and stratified by type of CSCR (focal vs diffuse).

The study has a 24-week study period with five scheduled visits: screening, randomisation (first treatment), 6-week follow up (with second treatment where eligible), 12-week follow-up , 18-week follow-up, and 24-week follow-up.

The primary outcome is the proportion of laser-treated study eyes that show resolution of sub-retinal fluid (SRF) as observed on optical coherence tomography (OCT) compared to sham-treated study eyes at 24 weeks.

The safety endpoint will be proportion of laser-treated eyes that lose ≥10 letters of of vision (measured on a standard vision chart) compared to sham-treated study eyes and fellow eyes over 24 weeks.

Study Overview

• Status: Recruiting
• Conditions: Central Serous Chorioretinopathy
• Intervention / Treatment: Device: 2RT subthreshold nanosecond laser - active; Device: 2RT subthreshold nanosecond laser - sham

• Study Type: Interventional
• Enrollment (Anticipated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Tom Spurling; Phone Number: +61 8 8362 0193; Email: tspurling@nova-eye.com
• Study Contact Backup: Name: Chris Baker; Phone Number: +61 8 8362 0193; Email: cbaker@nova-eye.com

Study Locations

• Australia
  • Victoria
    • East Melbourne, Victoria, Australia, 3002
      • Recruiting
      • Centre for Eye Research Australia
      • Contact: Carly Parfett; Phone Number: +61 3 9929 8263; Email: cera-rgo@cera.org.au
      • Contact: Rebecca Singleton; Phone Number: +61399298369; Email: cera-rgo@cera.org.au
      • Principal Investigator: Mali Okada, MBBS FRANZCO
      • Sub-Investigator: Robyn H Guymer, MBBS FRANZCO
      • Sub-Investigator: Sanjeewa Wickremasinghe, MBBS FRANZCO
      • Sub-Investigator: Amy Cohn, MBBS FRANZCO
    • Glen Iris, Victoria, Australia, 3146
      • Recruiting
      • Retinology Institute
      • Contact: Wilson Heriot, MBBS FRANZCO; Phone Number: +61 3 8823 9000; Email: info@retinology.com.au

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Age 18-70 years
2. Both males and females
3. Individuals with non-resolving CSCR as defined by presence of any SRF on OCT for > 3 months from date of diagnosis to randomisation visit
4. BCVA of 35 to 80 letters (Snellen equivalent of 6/6 to 6/60) in the study eye
5. Ability, willingness and sufficient cognitive awareness to consent to the trial, received randomised SNL treatment or sham procedure, and complete all visits as per the study schedule

Exclusion Criteria:

1. A need for extraneous, continuous steroids to control any disease, including both systemic steroids (e.g., for systemic autoimmune conditions) and ocular steroids (e.g., for uveitis), or ongoing anabolic steroid use
2. Any systemic disease that leads to elevated endogenous steroid levels including raised 24h urinary cortisol level > 100 ug/24h consistent with Cushing's syndrome

3. Any ocular disease in the study eye, other than CSCR, which in the opinion of the investigator may significantly compromise assessment of the retina, or which would compromise the ability to assess any effect following SNL treatment including, but not limited to:

   • Age related macular degeneration
   • Any evidence of a neovascular membrane in the macular (either exudative or non-exudative)
   • Diabetic retinopathy (unless limited to fewer than 10 microaneurysms and/or small retinal haemorrhages, without retinal thickening on OCT)
   • Macular pathology or pigmentary abnormalities including but not limited to: pattern dystrophy, myopic maculopathy, angioid streaks, resumed ocular histoplasmosis syndrome, visually-significant epiretinal membranes, macular hole or pseudohole
   • Optic nerve pathology, including optic atrophy, history of optic neuropathy
   • Myopic crescent wider than 50% of the longest diameter of the optic disc, or closer than 1500 µm to the fovea
   • Retinal vascular diseases including branch or central vein or artery occlusion
   • Choroidal nevus within 2 DD of the fovea associated with depigmentation or overlying drusen, if these drusen are used to determine eligibility
   • Active uveitis or ocular inflammation
   • Corneal pathology precluding visualization of fundus or increasing the risk of using a contact lens, such as corneal dystrophy, recurrent corneal erosion syndrome or sensitivity to the application of a contact lens
4. History or presence of uncontrolled glaucoma or raised intraocular pressure which would preclude safe dilation of the pupil to allow adequate assessment and application of SNL treatment
5. History of prior laser surgery to the retina including subthreshold laser (focal retinopexy for a peripheral retinal tear performed more than 90 days prior to the entry into the study is permitted)
6. Significant cataract or other ocular media which, in the opinion of the investigator, significantly limits the visual acuity or view of the retina
7. Cataract surgery within three months preceding baseline, or a history of post-operative complications within the last 12 months preceding baseline in the study eye (uveitis, cyclitis, etc.)
8. Previous retinal or ocular surgery, the effects of which may now or in the future complicate assessment of CSCR (routine cataract surgery more than 3 months prior is permitted)
9. Known hypersensitivity to fluorescein
10. Use of any systemic or ocular medication known to be toxic to the retina, excluding tamoxifen unless there is evidence of toxicity
11. Pregnant or lactating women
12. Current participation in any other investigational ophthalmological clinical trial
13. Other health-related reasons which make an individual inappropriate for participation in this study based on the investigator's medical judgment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Active laser; Application of the active 2RT sub threshold laser	Device: 2RT subthreshold nanosecond laser - active; The 2RT™ Q-switched YAG laser (532nm) delivering 3 nanosecond pulses; 400 um spot size, is a pulsed subthreshold nanosecond (SNL) laser, which uses low energy levels to produce limited effects that selectively target melanosomes within the pigmented retinal pigment epithelial (RPE) cells.; Other Names: 2RT; SNL
Sham Comparator: Sham laser; Application of sham laser (i.e. flashing lights which replicate the look of active laser to the participant)	Device: 2RT subthreshold nanosecond laser - sham; Application of sham laser (i.e. flashing lights which replicate the look of active laser to the participant) from the 2RT subthreshold nanosecond laser device.; Other Names: Sham laser

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Resolution of sub-retinal fluid in study eyes	The change in amount of sub-retinal fluid (SRF) as observed on optical coherence tomography (OCT) imaging in the SNL-treated compared to sham-treated study eyes over 24 weeks.	24 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety Endpoint	The proportion of eyes that lose ≥10 letters of best corrected visual acuity (BCVA) in the SNL-treated compared to sham-treated study and fellow eyes over 24 weeks.	24 weeks

Collaborators and Investigators

• Sponsor: Nova Eye Medical Pty Ltd.
• Collaborators: Centre for Eye Research Australia
• Investigators: Principal Investigator: Mali Okada, MBBS FRANZCO, Centre for Eye Research Australia

Study record dates

Study Major Dates

• Study Start (Actual): October 18, 2022
• Primary Completion (Anticipated): December 31, 2023
• Study Completion (Anticipated): December 31, 2023

Study Registration Dates

• First Submitted: October 4, 2022
• First Submitted That Met QC Criteria: October 4, 2022
• First Posted (Actual): October 6, 2022

Study Record Updates

• Last Update Posted (Actual): March 29, 2023
• Last Update Submitted That Met QC Criteria: March 28, 2023
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Keywords: Laser; Subthreshold nanosecond laser; 2RT; CSR; Central Serous Chorioretinopathy; Chorioretinopathy
• Additional Relevant MeSH Terms: Eye Diseases; Retinal Diseases; Central Serous Chorioretinopathy
• Other Study ID Numbers: NANO-C

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No