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

A Phase II/III Study of Encapsulated Human NTC-201 Cell Implants Releasing Ciliary Neurotrophic Factor (CNTF) for Participants With Retinitis Pigmentosa Using Visual Field Sensitivity as the Primary Outcome


Lead Sponsor: Neurotech Pharmaceuticals

Source Neurotech Pharmaceuticals
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).

Overall Status Completed
Start Date January 2007
Completion Date July 2010
Primary Completion Date July 2010
Phase Phase 2
Study Type Interventional
Primary Outcome
Measure Time Frame
Change in Humphrey visual field sensitivity from baseline to month 12. 12 months
Secondary Outcome
Measure Time Frame
Change in visual field sensitivity 24 months
Mean, median and distribution of change in Best Corrected Visual Acuity 12 to 24 months
Change in ERG 12 to 24 months
Change in OCT 12 to 24 months
Change in inflammation 12 to 24 months
Change in vision-related quality of life 12 to 24 months
Enrollment 68

Intervention Type: Drug

Intervention Name: NT-501

Description: High Dose

Arm Group Label: 1 NT-501 implant

Other Name: CNTF implant

Intervention Type: Drug

Intervention Name: NT-501

Description: Low Dose

Arm Group Label: 2 NT-501 implant

Other Name: CNTF implant



Study inclusion / 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.

Gender: All

Minimum Age: 18 Years

Maximum Age: 64 Years

Healthy Volunteers: No

Overall Official
Last Name Role Affiliation
Weng Tao, MD, PhD Study Director Neurotech Pharmaceuticals
Retina-Vitreous Associates Medical Group | Beverly Hills, California, 90211, United States
University of Califoria, Davis | Sacramento, California, 95817, United States
University of California, San Francisco | San Francisco, California, 94143-0730, United States
Bascom Palmer Eye Insitute | Miami, Florida, 33101, United States
Ophthalmic Consultants of Boston | Boston, Massachusetts, 02114, United States
Kellogg Eye Center | Ann Arbor, Michigan, 48105, United States
University of Minnesota | Minneapolis, Minnesota, 55455-0501, United States
NY University Medical Center | New York, New York, 10016, United States
Casey Eye Institue | Portland, Oregon, 97239-4197, United States
The Hamilton Eye Institute | Memphis, Tennessee, 38163, United States
Retina Foundation of Southwest | Dallas, Texas, 75231, United States
University of Utah | Salt Lake City, Utah, 84112, United States
Location Countries

United States

Verification Date

November 2016

Responsible Party

Type: Sponsor

Has Expanded Access No
Condition Browse
Number Of Arms 2
Arm Group

Label: 1 NT-501 implant

Type: Experimental

Description: High Dose

Label: 2 NT-501 implant

Type: Experimental

Description: Low Dose

Study Design Info

Allocation: Randomized

Intervention Model: Parallel Assignment

Primary Purpose: Treatment

Masking: Double (Participant, Outcomes Assessor)

Source: ClinicalTrials.gov