Safety Study to Evaluate Bilateral CNTF Implants in Subjects With MacTel Type 2

Phase II, Multicenter, Open-label Safety Study of Bilateral NT-501 in Participants With Macular Telangiectasia Type 2

This is a multi-center, open-label, 6-month study to evaluate the safety of bilateral CNTF implants in participants with Macular Telangiectasia Type 2.

Study Overview

• Status: Completed
• Conditions: Macular Telangiectasia Type 2
• Intervention / Treatment: Combination product: NT-501 CNTF implant

Detailed Description

This was a multicenter, open-label study designed to evaluate the safety of bilateral NT-501 in subjects with MacTel. All subjects who received NT-501 in a single eye prior to or in the Phase 1/2 extension study (NTMT-01/02E) or in 1 of the 2 Phase 3 studies (NTMT-03-A or NTMT-03-B), and met all other eligibility criteria, qualified for participation in the current study; enrolled subjects underwent intraocular implantation of NT-501 in the fellow eye and were followed for 6 months. Note that, throughout this report, all references to "study eye" mean the eye that received NT-501 in the current study (ie, not the eye that was treated in the previous study).

• Study Type: Interventional
• Enrollment (Actual): 33
• Phase: Phase 2

Contacts and Locations

Study Locations

• Australia
  • New South Wales
    • Sydney, New South Wales, Australia
      • Save Sight Institute
  • Victoria
    • East Melbourne, Victoria, Australia, 3002
      • Centre for Eye Research Australia
  • Western Australia
    • Nedlands, Western Australia, Australia, 6009
      • Lions Eye Institute
• United States
  • California
    • Los Angeles, California, United States, 90095
      • Jules Stein Eye Institute
  • District of Columbia
    • Washington, District of Columbia, United States, 20892
      • National Eye Institute
  • Florida
    • Miami, Florida, United States, 33136
      • Bascom Palmer
  • Massachusetts
    • Boston, Massachusetts, United States, 02114
      • Massachusetts Eye and Ear Infirmary, Retina Service
  • Michigan
    • Ann Arbor, Michigan, United States, 48105
      • University of Michigan, Kellogg Eye Center
  • Ohio
    • Beachwood, Ohio, United States, 44122
      • Retina Associates of Cleveland, Inc.
  • Texas
    • Houston, Texas, United States, 77030
      • Retina Consultants of Texas

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

General Inclusion Criteria

1. Participants from the NTMT-03 study must have completed the Month-24 visit
2. Participant in the MacTel Phase 1/2 extension (NTMT-01/02E) study or the Phase 3 study must exit these studies prior to entering the Bilateral Implant safety study (NTMT-02B)
3. Participant must be willing and able to follow the study instructions and be willing and able to complete all required study procedures and visits
4. Participant must be willing and able to provide a signed Informed Consent, as well as written documentation in accordance with the relevant country and local privacy requirements, e.g., written data protection consent
5. Females of childbearing potential must consent to a pregnancy test before entering the study
6. A participant's refusal to allow the collection of blood samples for analysis of serum CNTF, serum Ab or Nab to CNTF, Ab to NTC-201.6A cells and Ab to DFHR levels in one eye will not exclude the participant from study participation

Ocular Inclusion Criteria

1. Participant must have a positive diagnosis of MacTel type 2 with evidence of fluorescein leakage typical of MacTel and at least one of the other features that include hyperpigmentation that is outside of a 500-micron radius from the center of the fovea, retinal opacification, crystalline deposits, right-angle vessels, or inner/outer lamellar cavities in the study eye
2. Participant must have steady fixation in the foveal or parafoveal area in the study eye and sufficiently clear media for good quality photographs

General Exclusion Criteria

1. Females of childbearing potential (those who are not surgically sterilized or post- menopausal, i.e., absence of menstruation for 12 months or longer) may not participate in the study if any of the following conditions exists:

   • Pregnant (positive pregnancy test at Visit 1 or intend to become pregnant during the study)
   • Nursing (lactating)
   • Do not agree to use adequate birth control methods for the duration of the study and until 90 days after the last administration of study drug (adequate birth control methods are: hormonal - oral, implantable, transdermal or injectable contraceptives; mechanical - spermicide in conjunction with a barrier such as condom or diaphragm, intrauterine device [IUD] or surgical sterilization of partner, or total sexual abstinence)
2. Participant is too ill to likely complete the entire study, based on the investigator's assessment
3. Participant, in the opinion of the investigator, is not suitable for study participation
4. Participant with any screening laboratory finding (serum chemistry, hematology, urinalysis) that in the opinion of the investigator is not suitable for study participation
5. Participant has a history or current evidence of severe hypersensitivity to the NT-501 implant
6. Participant has a history or current evidence of a medical condition (systemic or ophthalmic disease, metabolic dysfunction, physical examination finding or clinical laboratory finding) that may in the opinion of the investigator preclude the safe administration of the NT-501 implant or adherence to the scheduled study visits, safe participation in the study or affect the results of the study (e.g., unstable or progressive cardiovascular, cerebral vascular, pulmonary, Parkinson's, liver or renal disease; depression, cancer, or dementia

Ocular Exclusion Criteria

1. Participant has a history or evidence of the following surgeries/procedures in the study eye, as assessed at Visit 1, including:

   • Submacular surgery
   • Vitrectomy
   • Retinal detachment
   • Incisional glaucoma surgery
   • Trabeculectomy or trabeculoplasty
   • Cataract surgery or laser-assisted in situ keratomileusis (LASIK) performed in the previous 6 months
2. Participant has uncontrolled glaucoma; or ocular hypertension, i.e., IOP ≥ 25 mmHg in the study eye
3. Participant has evidence of intraretinal or subretinal neovascularization or central serous chorioretinopathy in the study eye
4. Participant has evidence of ocular disorder(s) in the study eye of a severity that could confound the interpretation of study results, compromise visual acuity or require medical or surgical intervention during the study period, including retinal vascular occlusion, severe nonproliferative or proliferative diabetic retinopathy, retinal detachment, macular hole, geographic atrophy, intraretinal or subretinal neovascularization, central serous chorio-retinopathy, pathological myopia
5. Participant has a vitreous hemorrhage in the study eye at Visit 1 (Screening)
6. Participant has a spherical equivalent of the refractive error in the study eye demonstrating more than 8 diopters of myopia
7. Participant has a history or evidence of penetrating ocular trauma in the study eye
8. Participant has an anticipated need for cataract extraction in the study eye within 6 months of Visit 1 (Screening) such as cortical opacity > standard 3, posterior subcapsular opacity > standard 2, or a nuclear opacity > standard 3 as measured on the Age-Related Eye Disease Study (AREDS) clinical lens grading system
9. Participant has uveitis, history of uveitis in either eye or history of ocular herpes virus in either eye
10. Participant has undergone major surgery within the last 6 months (systemic or ocular in either eye) or who are likely to require major surgery within 6 months of Visit 1 (Screening)
11. Participant has periocular or ocular/intraocular infection or inflammation in either eye (such as infectious conjunctivitis, keratitis, scleritis, endophthalmitis) within 3 months prior to Visit 1 (Screening)
12. Participant has ocular hypotension in either eye (<6 mmHg) that in the opinion of the Investigator would interfere with the NT-501 implant insertion
13. Participant has a history of scleritis, scleral thinning, periocular, ocular, or intraocular infection or inflammation, cicatrizing conjunctival diseases any other ocular conditions in the study eye that could interfere with or complicate the surgery associated with NT-501implant insertion

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: NT-501 in Fellow Eye; NT-501 was implanted on Day 0 in the fellow eye of subjects who received a single NT-501 in a previous study; subjects were followed for 6 months post-implantation of NT-501 in this study.	Combination product: NT-501 CNTF implant; Single implantation of CNTF-secreting NT-501 device into fellow (untreated) eye

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Frequency of Ocular and/or Non-ocular Treatment Emergent Adverse Events	Assess the incidence and severity of adverse events (AEs) following bilateral ocular implantation of NT-501	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Serum Levels of CNTF and Immunogenicity for NT-501	Incidence of positive serum levels of CNTF and immunogenicity for NT-501 with quantification of antibodies (Ab) to CNTF, neutralizing antibodies (NAb) to CNTF, Ab to NTC-201-6A cells, and Ab to mouse dihydrofolate reductase (mDHFR) at any time.	6 months

Collaborators and Investigators

• Sponsor: Neurotech Pharmaceuticals
• Collaborators: The Lowy Medical Research Institute Limited
• Investigators: Study Director: Thomas Aaberg, Jr, MD, Neurotech Pharmaceuticals, LLC

Publications and helpful links

General Publications

• Chew EY, Clemons TE, Jaffe GJ, Johnson CA, Farsiu S, Lad EM, Guymer R, Rosenfeld P, Hubschman JP, Constable I, Wiley H, Singerman LJ, Gillies M, Comer G, Blodi B, Eliott D, Yan J, Bird A, Friedlander M; Macular Telangiectasia Type 2-Phase 2 CNTF Research Group. Effect of Ciliary Neurotrophic Factor on Retinal Neurodegeneration in Patients with Macular Telangiectasia Type 2: A Randomized Clinical Trial. Ophthalmology. 2019 Apr;126(4):540-549. doi: 10.1016/j.ophtha.2018.09.041. Epub 2018 Oct 4.

Study record dates

Study Major Dates

• Study Start (Actual): July 21, 2021
• Primary Completion (Actual): December 8, 2022
• Study Completion (Actual): December 8, 2022

Study Registration Dates

• First Submitted: January 25, 2021
• First Submitted That Met QC Criteria: January 25, 2021
• First Posted (Actual): January 29, 2021

Study Record Updates

• Last Update Posted (Estimated): March 26, 2025
• Last Update Submitted That Met QC Criteria: March 7, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: CNTF; Macular Telangiectasia Type 2; Mactel
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Telangiectasis
• Other Study ID Numbers: NTMT-02B

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: Yes
• Studies a U.S. FDA-regulated device product: Yes