REP1 Gene Replacement Therapy for Choroideremia

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)

The assessment of the efficacy (with respect to preservation of visual function and retinal structure) and safety of a single subretinal injection of AAV2.REP1 in participants with a confirmed diagnosis of choroideremia, as evaluated by various functional and anatomical outcomes measured over a number of time points up to 24 months post-treatment.

Inclusion Criteria:

1. Candidate is willing and able to give informed consent for participation in the study.
2. Male aged 18 years or above.
3. Genetic or molecular confirmed diagnosis of choroideremia (REP1 protein deficiency).
4. Active disease visible clinically within the macula region.
5. Best corrected visual acuity better than or equal to 6/60 (20/200; Decimal 0.1; LogMAR 1.0) in the study eye.

Exclusion Criteria:

1. Any female, or a male aged below 18 years.
2. An additional cause for sight loss (e.g. amblyopia) in the eye to be treated.
3. Any other significant ocular and non-ocular disease or disorder which, in the opinion of the investigator, may put the participants at risk because of participation in the study.
4. Inability to take systemic prednisolone for a period of 45 days.
5. Unwillingness to use barrier contraception methods for a period of three months following gene therapy surgery.
6. Participation in another research study involving an investigational product in the preceding 12 weeks.