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Choroideremia Gene Therapy Clinical Trial

An Open Label Phase 2 Clinical Trial of Retinal Gene Therapy for Choroideremia Using an Adeno-associated Viral Vector (AAV2) Encoding Rab-escort Protein 1 (REP1)

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02553135
Enrollment
6
Registered
2015-09-17
Start date
2015-09-30
Completion date
2018-02-28
Last updated
2019-07-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Choroideremia

Keywords

choroideremia, gene therapy

Brief summary

Phase II gene therapy study, involving a total of 6 male patients with choroideremia. The study will be conducted at the Bascom Palmer Eye Institute, University of Miami. Patients will be required to attend a total of 11 study visits over a 24 month period with an additional 3 year follow-up.

Detailed description

This is a Phase II, open label study involving patients with a clinical phenotype of choroideremia and a confirmed CHM genotype. Following consent, patients will be required to attend an initial screening visit (Visit 1). Within 2 weeks of the screening visit patients will undergo a surgical procedure (Visit 2) under general anesthesia which will include a standard vitrectomy, retinal detachment and administration of a subretinal injection of AAV2-REP1 (1x1011 genome particles). Patients will be required to attend a further 9 study visits (Visits 3-11) over a 24 month period for functional, and anatomical assessments as well as monitoring of adverse events. The primary endpoint is the change from baseline in visual acuity in the study eye, compared to control eye. Secondary study endpoints are, change from baseline in autofluorescence evaluation, microperimetry readings and other anatomic and functional outcomes (all in the study eye compared to control eye). Secondary endpoints also include safety assessments to be conducted throughout the study. The fellow eyes of these patients will be utilized as controls in this study and will receive no study treatment.

Interventions

BIOLOGICALInjection of AAV2-REP1 (10e11 vg)

Single Group: single arm study

Sponsors

Byron Lam
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* 18 Years and older * Male * Able to give informed consent * Genetically confirmed diagnosis of choroideremia * Active disease visible clinically within the macula region * Best-corrected visual acuity equal to or worse than 20/32 but better than or equal to 20/200 in the study eye.

Exclusion criteria

* Female * Under the age of 18 * History of amblyopia in the study eye * Men unwilling to use barrier contraception methods * Relevant grossly asymmetrical disease or other ocular morbidity which might confound use of the fellow eye as a long-term control * Any other significant ocular and non-ocular disease/disorder or retinal surgery * Contraindication to use of medications or contrast agents * Participated in research study involving an investigational product in the past 12 weeks * Having had gene or cellular therapy at any time prior to this study.

Design outcomes

Primary

MeasureTime frameDescription
Change in Best Corrected Visual Acuity From BaselineBaseline, 24 MonthsPatients will have an assessment of visual acuity using the Early Treatment of Diabetic Retinopathy Study (ETDRS) vision charts in both eyes. Low Luminance BCVA was measured by placing a 2.0 log unit neutral density filter over the best correction for that eye and having the participant read the normally illuminated ETDRS chart and was reported as the number of letters read correctly (ranging from 0 to 100 letters) in the study eye. The lower the number of letters read correctly on the eye chart, the worse the vision (or visual acuity). The study eye was defined as the eye that met inclusion/exclusion criteria with the worst standard BCVA. If the BCVA in both eyes was similar the Patient determines the worse eye be selected as the study eye. A positive change from baseline indicates an improvement and a negative change from baseline indicates a worsening.

Secondary

MeasureTime frameDescription
Change in Retinal Macular Autofluorescence From Baseline12 and 24 monthsMeasured in mm\^2 by Fundus Autofluorescence and shows changes in the integrity and metabolism of retinal cells. A negative change from baseline indicates a decrease in size of the retained retina (worsening; disease progression).
Changes in Microperimetry From BaselineBaseline to 24 monthsMicroperimetry assessments. A negative change from baseline indicates disease worsening.
Number of Participants Who Experience an Adverse Event24 monthsAdverse events during treatment and follow-up period

Countries

United States

Participant flow

Participants by arm

ArmCount
Injection of AAV2-REP1
Injection of AAV-REP1, 1.00x10e11 vg, subretinal injection of total volume of 100 μL. Injection of AAV2-REP1 (10e11 vg): Single Group: single arm study
6
Total6

Baseline characteristics

CharacteristicInjection of AAV2-REP1
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
1 Participants
Age, Categorical
Between 18 and 65 years
5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
6 Participants
Sex: Female, Male
Female
0 Participants
Sex: Female, Male
Male
6 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 6
other
Total, other adverse events
6 / 6
serious
Total, serious adverse events
0 / 6

Outcome results

Primary

Change in Best Corrected Visual Acuity From Baseline

Patients will have an assessment of visual acuity using the Early Treatment of Diabetic Retinopathy Study (ETDRS) vision charts in both eyes. Low Luminance BCVA was measured by placing a 2.0 log unit neutral density filter over the best correction for that eye and having the participant read the normally illuminated ETDRS chart and was reported as the number of letters read correctly (ranging from 0 to 100 letters) in the study eye. The lower the number of letters read correctly on the eye chart, the worse the vision (or visual acuity). The study eye was defined as the eye that met inclusion/exclusion criteria with the worst standard BCVA. If the BCVA in both eyes was similar the Patient determines the worse eye be selected as the study eye. A positive change from baseline indicates an improvement and a negative change from baseline indicates a worsening.

Time frame: Baseline, 24 Months

ArmMeasureValue (MEAN)Dispersion
Injection of AAV2-REP1Change in Best Corrected Visual Acuity From Baseline3.0 LettersStandard Deviation 4
Secondary

Change in Retinal Macular Autofluorescence From Baseline

Measured in mm\^2 by Fundus Autofluorescence and shows changes in the integrity and metabolism of retinal cells. A negative change from baseline indicates a decrease in size of the retained retina (worsening; disease progression).

Time frame: 12 and 24 months

ArmMeasureGroupValue (MEAN)Dispersion
Injection of AAV2-REP1Change in Retinal Macular Autofluorescence From BaselineBaseline to 12 Months-3.4 mm^2Standard Deviation 3.6
Injection of AAV2-REP1Change in Retinal Macular Autofluorescence From BaselineBaseline to 24 Months2.8 mm^2Standard Deviation 2.9
Secondary

Changes in Microperimetry From Baseline

Microperimetry assessments. A negative change from baseline indicates disease worsening.

Time frame: Baseline to 24 months

ArmMeasureValue (MEAN)Dispersion
Injection of AAV2-REP1Changes in Microperimetry From Baseline0.823 Average Threshold dBStandard Deviation 1.789
Secondary

Number of Participants Who Experience an Adverse Event

Adverse events during treatment and follow-up period

Time frame: 24 months

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Injection of AAV2-REP1Number of Participants Who Experience an Adverse Event6 Participants

Source: ClinicalTrials.gov · Data processed: Feb 24, 2026