Trial Outcomes & Findings for A Study of Encapsulated Cell Technology (ECT) Implant for Patients With Late Stage Retinitis Pigmentosa (NCT NCT00447993)

Last Updated: 2024-08-13

Results Overview

The primary efficacy endpoint was the proportion of patients demonstrating an improvement in best-corrected visual acuity (BCVA), defined as an increase of 10 letters or more at the 1-Year post-implant visit (pre-explant, if explant is completed). No response is defined as an improvement of \<10 letters.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

67 participants

Primary outcome timeframe

12 months post-implant

Results posted on

2024-08-13

Participant Flow

The total number of participant in the low dose group was 22 and the high dose group was 45 since each patient consented to treatment in one eye and sham treatment in the other eye.

Unit of analysis: Eyes

Participant milestones

Participant milestones
Measure	Low Dose Arm - Implant NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	Low Dose Arm - Sham Sham Implant in Fellow Eye (Low Dose Arm)	High Dose Arm - Implant NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	High Dose Arm - Sham Sham Implant in Fellow Eye (High Dose Arm)
Overall Study STARTED	22 22	22 22	45 45	45 45
Overall Study COMPLETED	22 22	22 22	41 41	41 41
Overall Study NOT COMPLETED	0 0	0 0	4 4	4 4

Reasons for withdrawal

Reasons for withdrawal
Measure	Low Dose Arm - Implant NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	Low Dose Arm - Sham Sham Implant in Fellow Eye (Low Dose Arm)	High Dose Arm - Implant NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	High Dose Arm - Sham Sham Implant in Fellow Eye (High Dose Arm)
Overall Study Lost to Follow-up	0	0	2	2
Overall Study Withdrawal by Subject	0	0	2	2

Baseline Characteristics

Two patients, both in the high dose were randomized but did not receive the implant and did not take part in the study. One of these participants ended study participation prior to completion of Visit 3 baseline visit. The other patient is included in the BCVA baseline data set; however, did not proceed with surgery.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Low Dose Arm - Implant n=22 Eyes NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	Low Dose Arm - Sham n=22 Eyes Sham Implant in Fellow Eye (Low Dose Arm)	High Dose n=45 Eyes NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	High Dose Arm - Sham n=45 Eyes Sham Implant in Fellow Eye (High Dose Arm)	Total n=134 Eyes Total of all reporting groups
Age, Continuous	41.1 Years STANDARD_DEVIATION 10.5 • n=22 Participants	41.1 Years STANDARD_DEVIATION 10.5 • n=22 Participants	42.0 Years STANDARD_DEVIATION 11.0 • n=45 Participants	42.0 Years STANDARD_DEVIATION 11.0 • n=45 Participants	41.7 Years STANDARD_DEVIATION 10.8 • n=67 Participants
Sex: Female, Male Female	8 Participants n=22 Participants	8 Participants n=22 Participants	25 Participants n=45 Participants	25 Participants n=45 Participants	66 Participants n=67 Participants
Sex: Female, Male Male	14 Participants n=22 Participants	14 Participants n=22 Participants	20 Participants n=45 Participants	20 Participants n=45 Participants	68 Participants n=67 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	3 Participants n=22 Participants	3 Participants n=22 Participants	2 Participants n=45 Participants	2 Participants n=45 Participants	10 Participants n=67 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	19 Participants n=22 Participants	19 Participants n=22 Participants	43 Participants n=45 Participants	43 Participants n=45 Participants	124 Participants n=67 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=22 Participants	0 Participants n=22 Participants	0 Participants n=45 Participants	0 Participants n=45 Participants	0 Participants n=67 Participants
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=22 Participants	1 Participants n=22 Participants	0 Participants n=45 Participants	0 Participants n=45 Participants	2 Participants n=67 Participants
Race (NIH/OMB) Asian	2 Participants n=22 Participants	2 Participants n=22 Participants	2 Participants n=45 Participants	2 Participants n=45 Participants	8 Participants n=67 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=22 Participants	0 Participants n=22 Participants	0 Participants n=45 Participants	0 Participants n=45 Participants	0 Participants n=67 Participants
Race (NIH/OMB) Black or African American	1 Participants n=22 Participants	1 Participants n=22 Participants	4 Participants n=45 Participants	4 Participants n=45 Participants	10 Participants n=67 Participants
Race (NIH/OMB) White	18 Participants n=22 Participants	18 Participants n=22 Participants	39 Participants n=45 Participants	39 Participants n=45 Participants	114 Participants n=67 Participants
Race (NIH/OMB) More than one race	0 Participants n=22 Participants	0 Participants n=22 Participants	0 Participants n=45 Participants	0 Participants n=45 Participants	0 Participants n=67 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=22 Participants	0 Participants n=22 Participants	0 Participants n=45 Participants	0 Participants n=45 Participants	0 Participants n=67 Participants
Ocular History - Years Since RP Diagnosis	24.66 Years STANDARD_DEVIATION 9.55 • n=22 Participants	24.66 Years STANDARD_DEVIATION 9.55 • n=22 Participants	21.50 Years STANDARD_DEVIATION 13.21 • n=45 Participants	21.50 Years STANDARD_DEVIATION 13.21 • n=45 Participants	22.52 Years STANDARD_DEVIATION 12.17 • n=67 Participants
Type of Ocular History Ocular Disease	22 Eyes n=22 Eyes	22 Eyes n=22 Eyes	45 Eyes n=45 Eyes	45 Eyes n=45 Eyes	134 Eyes n=134 Eyes
Type of Ocular History Ocular Surgery	11 Eyes n=22 Eyes	9 Eyes n=22 Eyes	21 Eyes n=45 Eyes	21 Eyes n=45 Eyes	62 Eyes n=134 Eyes
Type of Ocular History Ocular Treatment	2 Eyes n=22 Eyes	2 Eyes n=22 Eyes	2 Eyes n=45 Eyes	2 Eyes n=45 Eyes	8 Eyes n=134 Eyes
BCVA Letter Score	45.5 Letters STANDARD_DEVIATION 11.2 • n=22 Eyes • Two patients, both in the high dose were randomized but did not receive the implant and did not take part in the study. One of these participants ended study participation prior to completion of Visit 3 baseline visit. The other patient is included in the BCVA baseline data set; however, did not proceed with surgery.	44.8 Letters STANDARD_DEVIATION 10.4 • n=22 Eyes • Two patients, both in the high dose were randomized but did not receive the implant and did not take part in the study. One of these participants ended study participation prior to completion of Visit 3 baseline visit. The other patient is included in the BCVA baseline data set; however, did not proceed with surgery.	45.0 Letters STANDARD_DEVIATION 10.4 • n=44 Eyes • Two patients, both in the high dose were randomized but did not receive the implant and did not take part in the study. One of these participants ended study participation prior to completion of Visit 3 baseline visit. The other patient is included in the BCVA baseline data set; however, did not proceed with surgery.	46.7 Letters STANDARD_DEVIATION 9.1 • n=44 Eyes • Two patients, both in the high dose were randomized but did not receive the implant and did not take part in the study. One of these participants ended study participation prior to completion of Visit 3 baseline visit. The other patient is included in the BCVA baseline data set; however, did not proceed with surgery.	45.5 Letters STANDARD_DEVIATION 10.3 • n=132 Eyes • Two patients, both in the high dose were randomized but did not receive the implant and did not take part in the study. One of these participants ended study participation prior to completion of Visit 3 baseline visit. The other patient is included in the BCVA baseline data set; however, did not proceed with surgery.

PRIMARY outcome

Timeframe: 12 months post-implant

Population: Results are based on participants who completed the 1-yr post implant visit/assessment.

Outcome measures

Outcome measures
Measure	Low Dose Arm - Implant n=21 Eyes NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	Low Dose Arm - Sham n=21 Eyes Sham Implant in Fellow Eye (Low Dose Arm)	High Dose n=42 Eyes NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	High Dose Arm - Sham n=42 Eyes Sham Implant in Fellow Eye (High Dose Arm)
The Primary Outcome is the Change in Best-corrected Visual Acuity (BCVA) Using the Electronic Visual Acuity (EVA) Technology at Month 12. Response (Greater than or equal to 10 letter improvement)	1 participants	1 participants	3 participants	1 participants
The Primary Outcome is the Change in Best-corrected Visual Acuity (BCVA) Using the Electronic Visual Acuity (EVA) Technology at Month 12. No Response	20 participants	20 participants	39 participants	41 participants

SECONDARY outcome

Timeframe: From initial implant to 18 months post-implant

Population: Data set provides details for each timepoint based on number of patients who completed BCVA procedure at the each applicable visit.

The key visits for efficacy assessments were Months 1, 3, 6, 12 and 18. At these time points, BCVA was measured 3 times and the mean outcome reported. The assessments were conducted by masked technicians. The change from baseline for BCVA was summarized by time. Response is defined as an improvement in visual acuity by an increase of 10 letters or more whereas no response is \<10 letters.

Outcome measures

Outcome measures
Measure	Low Dose Arm - Implant n=22 Participants NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	Low Dose Arm - Sham n=22 Participants Sham Implant in Fellow Eye (Low Dose Arm)	High Dose n=43 Participants NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina	High Dose Arm - Sham n=43 Participants Sham Implant in Fellow Eye (High Dose Arm)
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 1 month post-implant: Response	1 Participants	1 Participants	3 Participants	1 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 1 month post-implant: No Response	21 Participants	21 Participants	40 Participants	42 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 3 months post-implant: Response	2 Participants	1 Participants	2 Participants	0 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 3 months post-implant: No Response	20 Participants	21 Participants	40 Participants	42 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 6 months post-implant: Response	1 Participants	0 Participants	4 Participants	2 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 6 months post-implant: No Response	20 Participants	21 Participants	38 Participants	40 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 12 months post-implant: Response	1 Participants	1 Participants	3 Participants	1 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 12 months post-implant: No Response	20 Participants	20 Participants	39 Participants	41 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 18 months post-implant: Response	0 Participants	2 Participants	2 Participants	0 Participants
Number of Participants With and Without Best Corrected Visual Acuity Response Over the 18-month Follow-up Period (Months 1, 3, 6, 12 and 18) 18 months post-implant: No Response	19 Participants	17 Participants	30 Participants	32 Participants

Adverse Events

Low Dose

Serious events: 1 serious events

Other events: 22 other events

Deaths: 0 deaths

High Dose

Serious events: 0 serious events

Other events: 42 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Low Dose n=22 participants at risk NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina Sham Implant in Fellow Eye	High Dose n=43 participants at risk；n=22 participants at risk NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina Sham Implant in Fellow Eye
Injury, poisoning and procedural complications Pelvic Fracture	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	0.00% 0/22 • Adverse Events were collected from time of the consent through 18 months post-implant.
Injury, poisoning and procedural complications Upper limb fracture	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	0.00% 0/22 • Adverse Events were collected from time of the consent through 18 months post-implant.

Other adverse events

Additional Information

CMO

Neurotech Pharmaceuticals, LLC

Phone: 401-333-3880

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	Low Dose n=22 participants at risk NT-501 Low Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina Sham Implant in Fellow Eye	High Dose n=43 participants at risk；n=22 participants at risk NT-501 High Dose Implant: encapsulated cell therapy that delivers ciliary neurotrophic factor to the retina Sham Implant in Fellow Eye
Eye disorders Abnormal sensation in eye	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	4.7% 2/43 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Anterior chamber cell	31.8% 7/22 • Number of events 7 • Adverse Events were collected from time of the consent through 18 months post-implant.	27.9% 12/43 • Number of events 12 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Anterior chamber flare	22.7% 5/22 • Number of events 5 • Adverse Events were collected from time of the consent through 18 months post-implant.	23.3% 10/43 • Number of events 10 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Cataract	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	4.7% 2/43 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Conjunctival cyst	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	2.3% 1/43 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Conjunctival Haemorrhage	72.7% 16/22 • Number of events 16 • Adverse Events were collected from time of the consent through 18 months post-implant.	74.4% 32/43 • Number of events 32 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Conjunctival Hyperaemia	50.0% 11/22 • Number of events 11 • Adverse Events were collected from time of the consent through 18 months post-implant.	34.9% 15/43 • Number of events 15 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Conjunctival Oedema	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	14.0% 6/43 • Number of events 6 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Eye inflammation	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	9.3% 4/43 • Number of events 4 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Eye irritation	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	7.0% 3/43 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Eye pain	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	16.3% 7/43 • Number of events 7 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Eye pruritis	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	9.3% 4/43 • Number of events 4 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Foreign body sensation in eyes	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	23.3% 10/43 • Number of events 10 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Macular Oedema	0.00% 0/22 • Adverse Events were collected from time of the consent through 18 months post-implant.	7.0% 3/43 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Maculopathy	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	2.3% 1/43 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Miosis	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	25.6% 11/43 • Number of events 11 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Pupils unequal	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	11.6% 5/43 • Number of events 5 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Vision blurred	13.6% 3/22 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.	7.0% 3/43 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Visual acuity reduced	0.00% 0/22 • Adverse Events were collected from time of the consent through 18 months post-implant.	7.0% 3/43 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Vitreous detachment	0.00% 0/22 • Adverse Events were collected from time of the consent through 18 months post-implant.	7.0% 3/43 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Vitreous disorder	13.6% 3/22 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.	16.3% 7/43 • Number of events 7 • Adverse Events were collected from time of the consent through 18 months post-implant.
Eye disorders Vitreous opacities	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	9.3% 4/43 • Number of events 4 • Adverse Events were collected from time of the consent through 18 months post-implant.
Gastrointestinal disorders Dyspepsia	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	2.3% 1/43 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.
Infections and infestations Bronchitis	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	4.7% 2/43 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.
Infections and infestations Nasopharyngitis	27.3% 6/22 • Number of events 6 • Adverse Events were collected from time of the consent through 18 months post-implant.	4.7% 2/43 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.
Infections and infestations Pneumonia	0.00% 0/22 • Adverse Events were collected from time of the consent through 18 months post-implant.	7.0% 3/43 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.
Infections and infestations Sinusitis	0.00% 0/22 • Adverse Events were collected from time of the consent through 18 months post-implant.	7.0% 3/43 • Number of events 3 • Adverse Events were collected from time of the consent through 18 months post-implant.
Injury, poisoning and procedural complications Post procedural complication	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	4.7% 2/43 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.
Injury, poisoning and procedural complications Post procedural haemorrhage	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	4.7% 2/43 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.
Injury, poisoning and procedural complications Procedural pain	31.8% 7/22 • Number of events 7 • Adverse Events were collected from time of the consent through 18 months post-implant.	11.6% 5/43 • Number of events 5 • Adverse Events were collected from time of the consent through 18 months post-implant.
Injury, poisoning and procedural complications Suture related complication	45.5% 10/22 • Number of events 10 • Adverse Events were collected from time of the consent through 18 months post-implant.	25.6% 11/43 • Number of events 11 • Adverse Events were collected from time of the consent through 18 months post-implant.
Nervous system disorders Headache	4.5% 1/22 • Number of events 1 • Adverse Events were collected from time of the consent through 18 months post-implant.	11.6% 5/43 • Number of events 5 • Adverse Events were collected from time of the consent through 18 months post-implant.
Respiratory, thoracic and mediastinal disorders Pharyngolaryngeal Pain	9.1% 2/22 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.	4.7% 2/43 • Number of events 2 • Adverse Events were collected from time of the consent through 18 months post-implant.