MacTel Laser Study

Controlled Pilot Study for Safety and Efficacy of Subthreshold Photothermal Therapy for Patients With Macular Telangiectasia (MacTel) Type 2

This is a two armed Single Masked Pilot Study enrolling participants with Macular Telangiectasia Type 2 who will be randomized to undergo either a subthreshold photothermal treatment or a sham procedure to one eye. The participants will be followed for one year with visits at 1 month, 3 months, 6 months and 12 months post-treatment (laser or sham). Due to the small number of participants enrolled in this study the data will be analyzed by descriptive statistics and exploratory figures. Summary statistics will be produced for study and fellow eyes.

Study Overview

• Status: Active, not recruiting
• Conditions: Macular Telangiectasia
• Intervention / Treatment: Device: 577-nm PASCAL laser

• Study Type: Interventional
• Enrollment (Actual): 9
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Wisconsin
    • Milwaukee, Wisconsin, United States, 53226
      • Medical College of Wisconsin & Froedtert Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 79 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Signed and dated written informed consent obtained from the participant in accordance with the local regulations;
2. Males/females 21 years of age and older but less than 80 years of age;
3. Participant must have a positive diagnosis of MacTel Type 2 in at least one eye with evidence of fluorescein leakage typical of MacTel or at least one of the other features including loss of retinal transparency/hyper-reflectivity to blue light, crystalline deposits, right angle vessels, inner/outer retinal low-reflective spaces, or hyperpigmentation not involving the center of the fovea, but no evidence of intraretinal/subretinal vascular proliferation;
4. Participant must have an Ellipsoid Zone (EZ, aka IS/OS) break in the study eye between 0.16 - 4.0 mm2 as measured on SD-OCT;
5. Participant's best-corrected visual acuity at least 55 letters (20/80) in the study eye;
6. Participant must have steady fixation in the foveal or parafoveal area of each eye, adequate pupil dilation and sufficiently clear media to perform multi-modal retinal imaging and treatment;

7. Participant must be able and willing to attend all scheduled visits.

   For Participants undergoing optional AOSLO imaging:

8. Participant should have reproducible baseline AOSLO image montages at 2 baseline imaging sessions with quality suitable to identify a minimum of 7 regions of interest (ROIs) at which reliable cone spacing measures can be made in each eye.

Exclusion Criteria:

1. Participant is unable to provide informed consent;
2. Participant is less than 21 years of age or greater than 80 years of age; (but less than 80);
3. Participant is medically unable to comply with study procedures or follow-up visits;
4. Participant received intravitreal therapy for non-neovascular MacTel in the study eye and in the fellow eye, injections no sooner than 3 months prior to study treatment;
5. Participant has nystagmus in either eye;
6. Participant has greater than 7 diopters myopia in either eye;
7. Participant has been diagnosed and treated for amblyopia in the study eye;
8. Participant has significant ocular abnormalities in either eye that prevent retinal assessment, including media opacities or cataract (up to Nuclear Sclerosis +1 is allowable);
9. Participant was a study participant in any other clinical trial of an intervention (drug or device) within the last 6 months;
10. Participant has a history of malignancy that would compromise the 12 month study survival; or
11. Participant has, in the opinion of the Investigator, any physical or mental condition that would increase the patient's risk of participation in the study or may interfere with the study procedures, evaluations and outcome assessments;
12. Presence of signs of advanced retinal/vascular disease in the study eye, such as CNV, haemorrhages or macular atrophy based on OCT or FAF;
13. Previous macular laser treatment in either eye;
14. Any previous ocular condition that may be associated with a risk of developing macular oedema;
15. Vitreomacular traction determined clinically and/or by OCT, which in the opinion of the investigator contributes to the macular oedema (associated or causing a detachment of the fovea) in the study eye;
16. Presence of other macular disease such as epiretinal membrane in the study eye;
17. Ocular or periocular infections;
18. Planned intra-ocular surgery in the study eye within one year; and
19. Patient is unavailable for follow-up visits.

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
Sham Comparator: Sham	Device: 577-nm PASCAL laser; The Topcon/Endpoint Management System™ is a cleared medical device commonly used in the treatment of ocular disorders.
Experimental: Subthreshold Photothermal Therapy	Device: 577-nm PASCAL laser; The Topcon/Endpoint Management System™ is a cleared medical device commonly used in the treatment of ocular disorders.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with treatment-related adverse events as assessed by CTCAE v4.0	To evaluate the safety and tolerability of subthreshold photothermal therapy in patients with MacTel Type 2 as assessed by CTCAE v4.0	3 months post treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline cone density as measured by confocal adaptive optics (AOSLO)	To evaluate the biological activity of subthreshold photothermal therapy in patients with MacTel Type 2.	1 year
Change in size of ellipsoid zone break area as measured by spectral domain optical coherence tomography (SD-OCT)	To evaluate the biological activity of subthreshold photothermal therapy in patients with MacTel Type 2.	1 year
Development or extension post therapy of areas of deficiency in cones as measured by AOSLO	To evaluate the biological activity of subthreshold photothermal therapy in patients with MacTel Type 2.	1 year

Collaborators and Investigators

• Sponsor: The Lowy Medical Research Institute Limited

Study record dates

Study Major Dates

• Study Start (Actual): February 8, 2018
• Primary Completion (Anticipated): December 31, 2022
• Study Completion (Anticipated): December 31, 2022

Study Registration Dates

• First Submitted: October 18, 2017
• First Submitted That Met QC Criteria: October 23, 2017
• First Posted (Actual): October 26, 2017

Study Record Updates

• Last Update Posted (Estimate): December 28, 2022
• Last Update Submitted That Met QC Criteria: December 27, 2022
• Last Verified: November 1, 2022

More Information

Terms related to this study

• Keywords: MacTel
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Telangiectasis
• Other Study ID Numbers: MacTelLaser1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes

Drug and device information, study documents

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