The purpose of this study is to assess the safety and tolerability of subretinal delivery of Adeno-associated Virus Vector (AAV5 hRKp.RPGR) gene therapy in adults and children with X-linked retinitis pigmentosa.

A Follow-on Study for Second-Eye Treatment for Participants Previously Treated With Gene Therapy for X-Linked Retinitis Pigmentosa (XLRP)

X-Linked Retinitis Pigmentosa

Retinal diseases

Eye Conditions

AAV5-hRKp.RPGR

No intervention (Follow-Up assessment)

An Open-label, Multicenter, Phase 2 Follow-on Study for Second Eye Treatment of Patients Previously Treated With a Recombinant Adeno-associated Virus Vector (AAV5 hRKp.RPGR) for Gene Therapy of Adults and Children With X-linked Retinitis Pigmentosa Owing to Defects in Retinitis Pigmentosa GTPase Regulator (RPGR)

An AE is any untoward medical occurrence in a clinical study participant administered a pharmaceutical (investigational or non investigational) product. An AE does not necessarily have a causal relationship with the intervention. An AE can be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non investigational) product, whether or not related to that medicinal (investigational or non investigational) product.

Change from baseline in BCVA by ETDRS chart letter scores in monocular assessment of the second treated eye will be assessed. BCVA was measured using the ETDRS Scale (ranging from 0 to 100 letters) in the study eye. An increase in the number of letters read correctly means that vision has improved and vice-versa.

Change in LLVA by ETDRS chart letter scores from baseline in monocular assessment of second treated eye will be assessed. Visual function assessments included LLVA assessment in each eye by ETDRS letters. The letter score ranges from 0 (worse score) to 100 (best score), and a gain in LLVA from baseline indicates an improvement in visual acuity.

Participants will receive a dose of AAV5 hRKp.RPGR under the retina (low-dose or intermediate-dose) on Day 1 depending on the dosage administered in study MGT009 (NCT03252847) in the past. After receiving the treatment, participants will be assessed for safety.

Participants will receive the treatment dose of AAV5 hRKp.RPGR under the retina (low-dose or intermediate-dose) on Day 1 in the second eye once the safety will be determined in Cohort 1.

The participants who are not willing to undergo surgery or are not eligible for surgery will be assessed in this cohort. They will be assessed yearly until 5 years after their initial eye surgery in previous study MGT009.

The purpose of this study is to assess the safety and tolerability of subretinal delivery
of Adeno-associated Virus Vector (AAV5 hRKp.RPGR) gene therapy in adults and children
with X-linked retinitis pigmentosa.

Massachusetts Eye and Ear Infirmary

University of Michigan Kellogg Eye Center

Moorfields Eye Hospital

An AE is any untoward medical occurrence in a clinical study participant administered a
pharmaceutical (investigational or non investigational) product. An AE does not
necessarily have a causal relationship with the intervention. An AE can be any
unfavorable and unintended sign (including an abnormal finding), symptom, or disease
temporally associated with the use of a medicinal (investigational or non
investigational) product, whether or not related to that medicinal (investigational or
non investigational) product.

Change from baseline in MRS10 in static perimetry of the second treated eye will be
measured.

Pointwise response in static perimetry within the full visual field in the second treated
eye will be assessed.

Pointwise response in static perimetry within the central 30 degrees visual field in the
second treated eye will be assessed.

Change from baseline in MRS90 in static perimetry of the second treated eye will be
assessed.

LLQ is a 32-item disease-specific questionnaire to assess self reported visual problems
under low luminance and at night. The range of responses is different for different
questions, with the overall pattern being that "1" means "No difficulty at all" and that
increasingly higher numbers mean increasingly more difficult.

Change in LLVA by ETDRS chart letter scores from baseline in monocular assessment of
second treated eye will be assessed. Visual function assessments included LLVA assessment
in each eye by ETDRS letters. The letter score ranges from 0 (worse score) to 100 (best
score), and a gain in LLVA from baseline indicates an improvement in visual acuity.

Change from baseline in BCVA by ETDRS chart letter scores in monocular assessment of the
second treated eye will be assessed. BCVA was measured using the ETDRS Scale (ranging
from 0 to 100 letters) in the study eye. An increase in the number of letters read
correctly means that vision has improved and vice-versa.

Participants will receive a dose of AAV5 hRKp.RPGR under the retina (low-dose or
intermediate-dose) on Day 1 depending on the dosage administered in study MGT009
(NCT03252847) in the past. After receiving the treatment, participants will be assessed
for safety.

Participants will receive the treatment dose of AAV5 hRKp.RPGR under the retina (low-dose
or intermediate-dose) on Day 1 in the second eye once the safety will be determined in
Cohort 1.

The participants who are not willing to undergo surgery or are not eligible for surgery
will be assessed in this cohort. They will be assessed yearly until 5 years after their
initial eye surgery in previous study MGT009.

A Follow-on Study for Second-Eye Treatment for Participants Previously Treated With Gene Therapy for X-Linked Retinitis Pigmentosa (XLRP)

Trials at a glance

Trials at a glance

A Follow-on Study for Second-Eye Treatment for Participants Previously Treated With Gene Therapy for X-Linked Retinitis Pigmentosa (XLRP)

Outcome measures

Primary outcome measures