ClinicalTrials.gg
CompletedNCT00447954Updated Mar 28, 2025Results posted

A Study of an Encapsulated Cell Technology (ECT) Implant for Patients With Atrophic Macular Degeneration

A Phase 2 interventional study of High Dose NT-501 implant and Low Dose NT-501 implant in Nonexudative Age-Related Macular Degeneration, Unspecified Eye, Intermediate Dry Stage, sponsored by Neurotech Pharmaceuticals. Completed at 8 sites in United States. Open to participants aged 50 Years and older. Per ClinicalTrials.gov, last updated 2025-03-28.

Sponsored by Neurotech Pharmaceuticals · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
53
Allocation
Randomized
Ages
50 Years and older
Sex
All
01

Study summary

The purpose of this study is to look at the safety and effectiveness of CNTF implants on vision in participants with atrophic macular degeneration. This research is being done because there are no effective therapies for people with atrophic macular degeneration. Age-related macular degeneration (AMD) is a condition that affects the macula, the central part of the retina that we use for seeing details. There are two types of AMD, one is the wet type in which new blood vessels grow, also known as choroidal neovascularization (CNV), but the other is the dry type in which the healthy cells die, and that is the target of this study. This is called atrophic macular degeneration. 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, as well as a sham surgery (or placebo) group.

Read the detailed description

Histopathologic studies of multiple forms of retinal neurodegenerative diseases have demonstrated the possibility of using the neurotrophic factor CNTF as an effective approach to reducing photoreceptor cell loss. Consequently, it had been hypothesized that the use of the implanted NT-501 capsule, which secretes CNTF into the vitreous, might be beneficial in people with atrophic macular degeneration. The purpose of this pilot study was to accumulate preliminary data on the effect of the intraocular NT-501 implant on visual acuity in patients with atrophic macular degeneration.

The study had a double-masked, multi-center, randomized, parallel group design. Eligible patients were randomized on a 2:1:1 basis to the higher CNTF output NTC-201-6A.02 implant, the lower CNTF output NTC-201-10.02 implant or to sham surgery, respectively.

The surgeon designated by the Principal Investigator (PI), the PI, vision examiners, reading center graders, and patients were all masked as to the dose of the implant. The patients and the vision examiners were masked as to which treatment was received.

Approximately 48 patients with geographic atrophy compatible with category 3 or 4 AMD were planned to be enrolled. All patients were to be followed clinically for 18 months. Patients randomized to the CNTF implants were implanted at baseline, had the option of being explanted at or after 12 months, and all were followed clinically for 18 months. Follow-up for safety occurred throughout the study period.

02

Conditions studied

  • Nonexudative Age-Related Macular Degeneration, Unspecified Eye, Intermediate Dry Stage

Keywords

  • eye disease
  • retinal disorder
  • CNTF
  • AMD
  • Atrophic AMD
03

In context

Eye Diseases

388 studies on the registry are indexed under Eye Diseases; 62 are open to participants now.

This study's enrollment of 53 is below the median of 62 across 269 interventional studies indexed under Eye Diseases.

Browse Eye Diseases studies →

Lead sponsor

Neurotech Pharmaceuticals is the lead sponsor of 13 studies on the registry; 2 are open to participants now.

Of its 8 completed or terminated interventional studies of FDA-regulated products, 7 (88%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
50 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Eligibility criteria

Study inclusion criteria:

  1. To participate in this study, the participant had to understand and sign the protocol's (if the participant's vision was impaired to the point where it was not possible to read the informed consent document, the informed consent document was read in its entirety to the participant).
  2. Women of (women with last menses \<1 year prior to screening) had to agree to use an effective form of from study onset until they completed the 18 month study visit.
  3. Participant had to be medically able to undergo ophthalmic surgery for NT-501 implant.
  4. Best-corrected visual acuity in the study eye between 20/50 and 20/200 (68-34 letter score) as measured using EVA.
  5. Presence in the study and/or fellow eye of geographic atrophy (GA) compatible with category 3 or 4 age-related macular degeneration (AMD) as defined by AREDS (AREDS, 2001). Also, the GA in the study eye had to be associated with vision loss as assessed by a vision test. GA was defined as one or more well-defined, usually more or less circular patches of partial or complete depigmentation of the RPE, typically with exposure of underlying choroidal blood vessels. Even if much of the RPE appeared to be preserved and large choroidal vessels were not visible, a roundish patch of RPE partial depigmentation might still be classified as early GA. A patch had to be at least 175 microns in area.
  6. Participants had steady fixation in the study eye in the foveal or parafoveal area with media clear enough for good quality photographs.

Study exclusion criteria:

  1. Participant less than 50 years of age (to minimize geographic atrophy from causes other than AMD).
  2. Participant medically unable to comply with study procedures or follow-up visits.
  3. Participant had evidence of ocular disease other than AMD that might confound the outcome of the study (e.g., diabetic retinopathy, uveitis, etc.).
  4. Participant had chronic requirement (e.g., > or = 4 weeks at a time) for ocular medications or had disease(s), that in the judgment of the examining physician, were vision threatening or might affect the primary outcome (artificial tears were permitted).
  5. Participant had evidence of classic or occult choroidal neovascularization in either eye, which might include serous RPE detachment, stippling on a fluorescein angiogram, macular edema, evidence of hemorrhage and lipid, and disciform scar.
  6. Participant had a requirement for acyclovir and/or related products during study duration. To be eligible for this study, the participant had to discontinue use of these products prior to enrollment and could not continue with the products until after they had completed the study.
  7. Participant had evidence of central serous chorio-retinopathy (CSR) in either eye.
  8. Participant had evidence of pathologic myopia in either eye.
  9. Participant had evidence of pseudovitelliform macular degeneration (a dominantly inherited disease characterized by a round or oval yellow subretinal macular deposit) in either eye.
  10. Participant was receiving systemic or other medications.
  11. Participant with evidence of vitreo-retinal traction maculopathy in either eye.
  12. Participant had a history of laser, photodynamic therapy (PDT), intravitreal injection of antivascular endothelial growth factor (VEGF) agent, or any previous treatment for AMD other than AREDS or equivalent supplement formulation.
  13. Prior history of vitrectomy, penetrating keratoplasty, trabeculectomy or trabeculoplasty.
  14. Participant had any of the following lens opacities: cortical opacity > standard 3, posterior subcapsular opacity > standard 3, or a nuclear opacity > standard 3 as measured on the AREDS clinical lens grading system.
  15. Participant had undergone lens removal in the last 3 months.
  16. Participant had participated in any other clinical trial of a drug or within the last 6 months.
  17. Participant was on chemotherapy.
  18. Participant was on ocular or systemic medications known to be toxic to the lens, retina, or optic nerve.
  19. Participant was pregnant or lactating.
  20. Participant had other retinal disease(s).
  21. Participant had a history of , except study participants with a history of successfully treated cancer (≥5 years prior to inclusion in the trial).
  22. Participant was considered immunodeficient or had a known history of .
  23. Participant with a history of ocular herpes zoster.
  24. Participant's fellow eye visual acuity worse than 20/400.
  25. Participant had undergone LASIK surgery or other refractive surgery for either eye in less than 6 months prior to screening.
  26. Participants with severe hearing disabilities in both ears.
  27. Participants with unmanaged diabetes, patients with CME, or retinopathy in either eye.
  28. Participant had a history of retinal detachment in either eye.
  29. Participant who had been diagnosed and treated for amblyopia as an infant.
  30. Participant with a history of Pars Plana Vitrectomy.
Terms in these criteria, in plain language(7)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Outcomes assessor)
Enrollment
53 participants (actual)

Study arms

  • Experimental
    1 - High Dose

    Participant had surgically implanted high dose (NT-501-6A.02) CNTF-secreting NT-501 device which produced \~20 ng/device/day.

    Combination Product: High Dose NT-501 implant

  • Experimental
    2 - Low Dose

    Participant had surgically implanted high dose (NT-501-6A.02) CNTF-secreting NT-501 device which produced \~5 ng/device/day.

    Combination Product: Low Dose NT-501 implant

  • Sham comparator
    3 - Sham

    Sham surgery procedure in which no device was implanted

    Other: Sham

Interventions

06

What researchers measure

Primary outcomes

  1. BCVA Response Defined as an Increased in 10 Letters at 1 Year Post-implant

    Response is defined as a improvement from baseline at Month 12 in monocular best visual acuity (BCVA) in the study eye of at least 10 letters as assessed by standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart.

    Time frame: 1 year post-implant

Secondary outcomes

  1. The Change in BCVA Over the 18-month Follow-up Period

    Change from baseline at post-baseline visits in monocular best visual acuity (BCVA) as assessed by standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart.

    Time frame: From initial implant 18 months post-implant

07

Results

Posted Mar 28, 2025

Participant flow

The study had a double-masked, multi-center, randomized, parallel group design. Patients were randomized on a 2:1:1 basis to the higher CNTF output NTC-201-6A.02 implant, the lower CNTF output NTC-201-10.02 implant or to sham surgery. A total of 53 patients were randomized to the treatment groups: 27 patients to the higher CNTF output NTC-201-6A.02 implant, 13 patients to the lower CNTF output NTC-201-10.02 implant and 13 patients to sham surgery.

Participant flow — Overall Study
MilestoneLow DoseHigh DoseSham
Started132713
Completed122312
Not completed141
Withdrew: Adverse event020
Withdrew: Withdrawal by subject011
Withdrew: Lost to follow-up010
Withdrew: Exclusionary event prior to implant procedure100

Outcome measures

PrimaryBCVA Response Defined as an Increased in 10 Letters at 1 Year Post-implant

Response is defined as a improvement from baseline at Month 12 in monocular best visual acuity (BCVA) in the study eye of at least 10 letters as assessed by standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart.

Time frame:
1 year post-implant
Reported as:
Number · eyes
BCVA Response Defined as an Increased in 10 Letters at 1 Year Post-implant
eyesLow DoseHigh DoseSham
Response331
No Response92411
SecondaryThe Change in BCVA Over the 18-month Follow-up Period

Change from baseline at post-baseline visits in monocular best visual acuity (BCVA) as assessed by standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart.

Time frame:
From initial implant 18 months post-implant
Reported as:
Mean · Letter score (number of letters)
The Change in BCVA Over the 18-month Follow-up Period
Letter score (number of letters)Low DoseHigh DoseSham
1 month post-implant - Treated-0.1 ± 6.61.5 ± 5.51.4 ± 6.2
1 month post-implant - Untreated1.0 ± 6.12.9 ± 6.50.5 ± 3.1
3 months post-implant - Treated-4.4 ± 7.93.0 ± 4.72.1 ± 8.8
3 months post-implant - Untreated-0.5 ± 4.42.3 ± 6.1-0.5 ± 6.7
4 months post-implant - Treated-0.8 ± 11.23.0 ± 5.92.9 ± 7.7
4 months post-implant - Untreated-1.0 ± 5.42.9 ± 7.20.3 ± 7.3
6 months post-implant - Treated-0.1 ± 11.82.7 ± 5.3-0.4 ± 7.7
6 months post-implant - Untreated-1.6 ± 9.31.5 ± 7.7-1.9 ± 6.1
12 months post-implant - Treated-0.3 ± 15.9-0.2 ± 8.4-1.3 ± 11.1
12 months post-implant - Untreated-4.6 ± 17.9-1.8 ± 14.4-6.0 ± 9.6
18 months post-implant - Treated-1.8 ± 18.4-5.3 ± 15.0-4.1 ± 13.7
18 months post-implant - Untreated-7.0 ± 14.6-3.7 ± 13.5-8.5 ± 11.1

Adverse events

Collected over All patients were to be followed clinically for 18 months. Patients could have the implant removed (explanted) from the eye after 12 months or earlier in case of adverse events (AEs) or at the patient's request. Patients were followed up to 18-months post implant.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Low Dose0/12 (0%)1/12 (8.3%)4/12 (33.3%)
High Dose1/27 (3.7%)10/27 (37%)8/27 (29.6%)
Sham0/12 (0%)1/12 (8.3%)2/12 (16.7%)
Most frequent serious events
Showing 10 of 25
Most frequent serious events
EventLow DoseHigh DoseSham
Atrial FibrillationCardiac disorders1/120/270/12
Choriodal NeovascularisationEye disorders0/120/271/12
Retinal HaemorrhageEye disorders0/120/271/12
FatigueGeneral disorders1/120/270/12
DyspnoeaRespiratory, thoracic and mediastinal disorders1/120/270/12
Acute Myocardial InfarctionCardiac disorders0/121/270/12
Cardiac ArrestCardiac disorders0/121/270/12
DiverticulumGastrointestinal disorders0/121/270/12
CellulitisInfections and infestations0/121/270/12
DiverticulitisInfections and infestations0/121/270/12
Most frequent other events
Showing 10 of 24
Most frequent other events
EventLow DoseHigh DoseSham
Suture Related ComplicationInjury, poisoning and procedural complications0/124/270/12
Conjuctival HaemorrhageEye disorders0/123/270/12
Anterior Chamber CellEye disorders1/122/270/12
Anterior Chamber FlareEye disorders1/120/270/12
Eye IrritationEye disorders0/122/271/12
Eye PainEye disorders1/122/271/12
Lacrimation IncreasedEye disorders1/121/270/12
MiosisEye disorders1/121/270/12
Ocular HyperaemiaEye disorders1/120/270/12
Visual DisturbanceEye disorders1/121/270/12

Baseline characteristics

Participants who were randomized to a study arm but prior to surgical procedure.

Age, Continuous
Age, Continuous(Years)Low DoseHigh DoseShamTotal
Mean78.3 ± 5.674.9 ± 7.574.5 ± 6.075.6 ± 6.8
Sex: Female, Male
Sex: Female, Male(Participants)Low DoseHigh DoseShamTotal
Female617528
Male710825
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)Low DoseHigh DoseShamTotal
Hispanic or Latino0000
Not Hispanic or Latino13271353
Unknown or Not Reported0000
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Low DoseHigh DoseShamTotal
American Indian or Alaska Native0000
Asian0000
Native Hawaiian or Other Pacific Islander0000
Black or African American0000
White13271353
More than one race0000
Unknown or Not Reported0000
Ocular History
Ocular History(Years)Low DoseHigh DoseShamTotal
Years since first diagnosed with AMD6.75 ± 6.818.39 ± 6.829.84 ± 9.068.34 ± 7.36
Years since ocular disease2.89 ± 3.543.44 ± 4.345.93 ± 9.633.92 ± 5.92
Years since ocular surgery5.99 ± 6.134.73 ± 4.312.49 ± 1.664.65 ± 4.64
Years since ocular treatment1.60 ± 0.05.18 ± 3.682.63 ± 0.03.65 ± 2.79
Type of Ocular History
Type of Ocular History(Participants)Low DoseHigh DoseShamTotal
Ocular Disease13271353
Ocular Surgery913628
Ocular Treatment1214
Baseline BCVA
Baseline BCVA(Letter score (# of letters read correct))Low DoseHigh DoseShamTotal
Treated Eye49.9 ± 10.253.5 ± 9.056.3 ± 6.653.2 ± 8.6
Untreated Eye55.7 ± 23.255.0 ± 21.668.1 ± 9.159.6 ± 18.0
08

Study locations

8 sites
  • Retina-Vitreous Associates Medical Group
    Beverly Hills, California 90211, United States
  • Retina Group of Florida
    Hollywood, Florida 33021-6746, United States
  • Bascom Palmer Eye Institute
    Miami, Florida 33101, United States
  • Ophthalmic Consultants of Boston
    Boston, Massachusetts 02114, United States
  • Beaumont Eye Institute
    Royal Oak, Michigan 48073-6710, United States
  • Retina Foundation of Southwest
    Dallas, Texas 75231, United States
  • Vitreoretinal Consultants
    Houston, Texas 77030, United States
  • University of Utah
    Salt Lake City, Utah 84132, United States
09

References and documents

Publications

  • 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. PubMed 23049090 ↗

Individual participant data

Plan to share: No

10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 28, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT00447954
Lead sponsor
Neurotech Pharmaceuticals
Responsible party
Sponsor
First posted
Mar 15, 2007
Start date
Jan 5, 2007
Primary completion
May 11, 2009
Completion
May 11, 2009
Results posted
Mar 28, 2025
Last update
Mar 28, 2025

Study contacts

Weng Tao, M.D., PhD
study director · Neurotech Pharmaceuticals

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Mar 2025. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Studies of the drug tested here: Ciliary Neurotrophic Factor

Start the discussion