NCT00447980

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.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
73

participants targeted

Target at P50-P75 for phase_2

Timeline
Completed

Started Jan 2007

Typical duration for phase_2

Geographic Reach
1 country

12 active sites

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

January 22, 2007

Completed
2 months until next milestone

First Submitted

Initial submission to the registry

March 9, 2007

Completed
6 days until next milestone

First Posted

Study publicly available on registry

March 15, 2007

Completed
3.1 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 19, 2010

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

April 19, 2010

Completed
15 years until next milestone

Results Posted

Study results publicly available

May 1, 2025

Completed
Last Updated

May 1, 2025

Status Verified

April 1, 2025

Enrollment Period

3.2 years

First QC Date

March 9, 2007

Results QC Date

April 28, 2022

Last Update Submit

April 14, 2025

Conditions

Retinitis Pigmentosa

Keywords

Retinitis Pigmentosaeye diseaseretinal disorderCNTF

Outcome Measures

Primary Outcomes (1)

  • Change in Humphrey Visual Fields - Total Sensitivity

    The primary efficacy endpoint was the change in Humphrey VFS from baseline to month 12 (Visit 10) as determined by the HVF 30-2 test, comprised of 76 points. The measure was the sum of actual thresholds for all 76 locations.

    12 months

Secondary Outcomes (2)

  • Change in Mean Humphrey Visual Fields Sensitivity

    Baseline compared to 6, 12, 18, 24 and 30 months

  • Mean Humphrey Visual Fields Sensitivity

    Baseline compared to 6, 12, 18, 24 and 30 months

Study Arms (2)

Low Dose

EXPERIMENTAL

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

Drug: NT-501

High Dose

EXPERIMENTAL

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

Drug: NT-501

Interventions

NT-501DRUG

Low Dose

Also known as: CNTF implant
Low Dose

Eligibility Criteria

Age18 Years - 64 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may not qualify if:

  • 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.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (12)

Retina-Vitreous Associates Medical Group

Beverly Hills, California, 90211, United States

Location

University of Califoria, Davis

Sacramento, California, 95817, United States

Location

University of California, San Francisco

San Francisco, California, 94143-0730, United States

Location

Bascom Palmer Eye Insitute

Miami, Florida, 33101, United States

Location

Kellogg Eye Center

Ann Arbor, Michigan, 48105, United States

Location

University of Minnesota

Minneapolis, Minnesota, 55455-0501, United States

Location

NY University Medical Center

New York, New York, 10016, United States

Location

Casey Eye Institue

Portland, Oregon, 97239-4197, United States

Location

The Hamilton Eye Institute

Memphis, Tennessee, 38163, United States

Location

Retina Foundation of Southwest

Dallas, Texas, 75231, United States

Location

University of Utah

Salt Lake City, Utah, 84112, United States

Location

The University of Utah - John A. Moran Eye Center

Salt Lake City, Utah, 84132, United States

Location

Related Publications (3)

  • 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.

    PMID: 23668681DERIVED

  • 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.

    PMID: 23049090DERIVED

  • 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.

    PMID: 21087953DERIVED

MeSH Terms

Conditions

Retinitis PigmentosaEye DiseasesRetinal Diseases

Interventions

Ciliary Neurotrophic Factor

Condition Hierarchy (Ancestors)

Eye Diseases, HereditaryRetinal DystrophiesRetinal DegenerationGenetic Diseases, InbornCongenital, Hereditary, and Neonatal Diseases and Abnormalities

Intervention Hierarchy (Ancestors)

Nerve Growth FactorsIntercellular Signaling Peptides and ProteinsPeptidesAmino Acids, Peptides, and ProteinsProteinsNerve Tissue ProteinsBiological Factors

Results Point of Contact

Title
Patricia Davis, Sr. Director of Clinical Operations
Organization
Neurotech USA, Inc.
p.davis@neurotechusa.com
401.333.3880

Study Officials

  • David Birch, MD, PhD

    Retina Foundation of the Southwest

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
No
Restrictive Agreement
Yes

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

March 9, 2007

First Posted

March 15, 2007

Study Start

January 22, 2007

Primary Completion

April 19, 2010

Study Completion

April 19, 2010

Last Updated

May 1, 2025

Results First Posted

May 1, 2025

Record last verified: 2025-04

Data Sharing

IPD Sharing
Will not share

Locations

US(12)