A Study of Encapsulated Cell Technology (ECT) Implant for Participants With Early Stage Retinitis Pigmentosa

NCT ID: NCT00447980

Last Updated: 2025-05-01

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE2
• Total Enrollment: 73 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2007-01-22
• Study Completion Date: 2010-04-19

Brief Summary

The purpose of this study is to look at the safety and effectiveness of CNTF implants on vision in persons with retinitis pigmentosa, Usher type II & III, and Choroideremia. This research is being done because there are no effective therapies for people with these retinal degenerations. They are genetic disorders that affect one's ability to see at night, and later cause tunnel vision and loss of central vision. Retinal degenerations affect the retina, a light sensitive layer of cells in the back of the eye. Slowly over time, these cells die and cause permanent loss of vision.

The implant is a small capsule that contains human retinal pigment epithelium cells. These cells have been given the ability to make CNTF and release it through the capsule membrane into the surrounding fluid. In this study, two different CNTF dose levels will be used: a high dose and a low dose in one eye, as well as a sham (or placebo) surgery in the other eye.

Detailed Description

This study will involve about 18 visits over 2½ years for specific tests of the participant's vision and health. These visits may include visual exams, blood draw for laboratory testing, brief medical history and exam, and occasionally a questionnaire (survey), in addition to the visit for the surgical procedures. The primary effectiveness outcome for this study will be a visual field score one year after the implant surgery. There will be about 12 centers participating in this study, and up to 60 people enrolled, across the US. Each participant joining the study who has completed initial screening will then be scheduled to have a brief surgical procedure performed on each eye, one of which will include a very small cell-filled implant. Follow-up visits for repeat assessments will be required regularly to determine if the implant being tested is safe and effective for use to treat retinitis pigmentosa (RP).

Conditions

Retinitis Pigmentosa

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Low Dose

NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina

Sham Implant in Fellow Eye

Group Type: EXPERIMENTAL

NT-501

Intervention Type: DRUG

Low Dose

High Dose

NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina

Sham Implant in Fellow Eye

Group Type: EXPERIMENTAL

NT-501

Intervention Type: DRUG

High Dose

Interventions

NT-501

Low Dose

Intervention Type: DRUG

NT-501

High Dose

Intervention Type: DRUG

Other Intervention Names

CNTF implant; CNTF implant

Eligibility Criteria

Exclusion Criteria

Criteria for patients to qualify for the study include, but are not limited to:

• Over 18 years of age, and less than 65 years of age
• Diagnosis of retinitis pigmentosa, Usher Syndrome Type 2 or 3 or Choroideremia
• Visual acuity no worse than 20/63
• Experience with at least two full threshold Humphrey Visual Field 30-2 tests, one completed within the year prior to enrolling in this study

The following criteria will exclude patients from the study:

• Pregnant or lactating females, or females planning to become pregnant during the study or not using an acceptable method of contraception.
• Retinitis pigmentosa caused by a classic syndrome, including Usher Type I
• Other eye diseases including advanced cataract.
• Chronic systemic disease requiring continuous treatment with systemic steroids, immunosuppressive medications or insulin.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 64 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Neurotech Pharmaceuticals

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

David Birch, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Retina Foundation of the Southwest

Locations

Retina-Vitreous Associates Medical Group

Beverly Hills, California, United States

University of Califoria, Davis

Sacramento, California, United States

University of California, San Francisco

San Francisco, California, United States

Bascom Palmer Eye Insitute

Miami, Florida, United States

Kellogg Eye Center

Ann Arbor, Michigan, United States

University of Minnesota

Minneapolis, Minnesota, United States

NY University Medical Center

New York, New York, United States

Casey Eye Institue

Portland, Oregon, United States

The Hamilton Eye Institute

Memphis, Tennessee, United States

Retina Foundation of Southwest

Dallas, Texas, United States

University of Utah

Salt Lake City, Utah, United States

The University of Utah - John A. Moran Eye Center

Salt Lake City, Utah, United States

Countries

United States

References

Birch DG, Weleber RG, Duncan JL, Jaffe GJ, Tao W; Ciliary Neurotrophic Factor Retinitis Pigmentosa Study Groups. Randomized trial of ciliary neurotrophic factor delivered by encapsulated cell intraocular implants for retinitis pigmentosa. Am J Ophthalmol. 2013 Aug;156(2):283-292.e1. doi: 10.1016/j.ajo.2013.03.021. Epub 2013 May 10.

Reference Type: DERIVED

PMID: 23668681 (View on PubMed)

Kauper K, McGovern C, Sherman S, Heatherton P, Rapoza R, Stabila P, Dean B, Lee A, Borges S, Bouchard B, Tao W. Two-year intraocular delivery of ciliary neurotrophic factor by encapsulated cell technology implants in patients with chronic retinal degenerative diseases. Invest Ophthalmol Vis Sci. 2012 Nov 1;53(12):7484-91. doi: 10.1167/iovs.12-9970.

Reference Type: DERIVED

PMID: 23049090 (View on PubMed)

Talcott KE, Ratnam K, Sundquist SM, Lucero AS, Lujan BJ, Tao W, Porco TC, Roorda A, Duncan JL. Longitudinal study of cone photoreceptors during retinal degeneration and in response to ciliary neurotrophic factor treatment. Invest Ophthalmol Vis Sci. 2011 Apr 6;52(5):2219-26. doi: 10.1167/iovs.10-6479.

Reference Type: DERIVED

PMID: 21087953 (View on PubMed)

Other Identifiers

CNTF 4

Identifier Type: -

Identifier Source: org_study_id