A Clinical Trial Evaluating the Safety and Efficacy of a Single Subretinal Injection of AGTC-501 in Participants With X-linked Retinitis Pigmentosa Caused by RPGR Mutations

Overview

About this study

The purpose of this study is to evaluate and compare 2 doses of AGTC-501 to an untreated control group. A single subretinal injection of AGTC-501 (300 μL containing either 2.6 × 1011 vg/mL [low dose] or 2.4 × 1012 vg/mL [high dose]) will be administered in subjects in 2 treatment groups (N=~42), while subjects in the untreated control group (N=~21) will be followed and evaluated up to Month 12, after which they will be eligible to receive treatment with the high dose of AGTC-501.
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Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

General Inclusion Criteria:

1. Provide written informed consent or assent (per local regulation), prior to the conduct of any study-related procedure. Participants who provide assent must have a parent, guardian, or legal representative provide written informed consent.
2. Be between 12 and 50 years of age (inclusive) at the time of informed consent and assent (as applicable).
3. Be male (XY chromosome) and have at least one documented pathogenic or likely pathogenic variant in the RPGR gene.
4. Have a clinical diagnosis of XLRP.
5. Be able and willing, as assessed by the Investigator, to follow study instructions, complete study assessments, comply with the protocol, and attend study visits for the duration of the study.

Ocular Inclusion Criteria (Study Eye):
6. Have a BCVA ≤ 78 letters (approximately Snellen, 20/32) and ≥ 34 letters (approximately Snellen, 20/200)
7. Have a LLVA ≤64 letters (approximately Snellen 20/50) in the study eye
8. Be able to perform all tests of visual and retinal function and structure in both eyes based on the participant's reliability, and fixation, in the study eye per the Investigator's discretion.
9. Have detectable baseline mean macular sensitivity .
10. Have a detectable sub-foveal ellipsoid zone (EZ) line as assessed by SD-OCT in the study eye and confirmed by the CRC.
11. If study eye will be at the discretion of the Investigator and/or Surgeon.

General Exclusion Criteria:

1. Have other known disease-causing mutations documented in the participant's medical history or identified through a retinal dystrophy gene panel, that in the opinion of the Investigator would interfere with the potential therapeutic effect of the study agent or the quality of the assessments.
2. For participants with herpes simplex virus (HSV):

1. Have history of oral or genital herpes and unable and/or unwilling to utilize prophylactic antiviral medication.
2. Have a history of ocular herpes.
3. Have active oral or genital herpes or are currently receiving treatment for HSV infection.
3. Have known sensitivity or allergy to systemic corticosteroids or other immunosuppressive medications.
4. Have used anti-coagulant agents that may alter coagulation (e.g., warfarin, heparin, apixaban, or high dose docosahexaenoic acid \[DHA; fish oil\]) within 7 days prior to study treatment administration (ibuprofen, aspirin, or similar are acceptable).
5. Have used systemic corticosteroids or other immunosuppressive medications within 3 months prior to screening and/or intend to use during screening. Corticosteroids used on an as-needed basis administered by insufflation, inhalation or local administration to the skin and mucosa such as Symbicort (budesonide/formoterol), Flonase (fluticasone propionate), and skin creams and ointments containing corticosteroids shall not be exclusionary.
6. If sexually active or planning to become sexually active, are unwilling to use barrier contraception for 3 months following treatment administration.
7. Are currently participating or recently participated in any other research
8. Have previously received any AAV gene therapy product, stem cell therapy, cell-based therapy, or similar biologics.
9. Have significant media opacity impacting evaluation of the retina or vitreous. administration.
10. Had intraocular surgery within 90 days of study treatment administration.
11. Have any active ocular/intraocular infection or inflammation (e.g., severe blepharitis, infectious conjunctivitis, keratitis, scleritis, endophthalmitis, idiopathic or autoimmune associated uveitis, or herpetic lesions).
12. Have a history of corticosteroid-induced raised IOP of \>25 mmHg following corticosteroid exposure, despite topical IOP-lowering pharmacologic therapy.
13. Have any artificial retinal implant or prosthesis.
14. Have absence of clear ocular media and/or inadequate pupil dilation to facilitate good quality SD-OCT images.
15. Have any history of rhegmatogenous retinal detachment.
16. Have myopia (spherical equivalent) exceeding -10 diopters (or axial length of \>30 mm if the Principal Investigator \[PI\] deems it appropriate to measure) or presence of pathologic myopia in the study eye.
17. Have passed the Low Contrast Ora-VNC mobility course at ≤0.35 lux light level in either eye or binocularly at any screening visit.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 8/05/2024. Questions regarding updates should be directed to the study team contact.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Raymond Iezzi, M.D.

Contact us for the latest status

Contact information:

Suzanne Wernimont CCRP

(507) 538-8119

Wernimont.Suzanne@mayo.edu

More information

Publications

Publications are currently not available