Observational Natural History Study of Autosomal Dominant Retinitis Pigmentosa (adRP)

Inclusion Criteria:

1. The subject has 1 documented pre-specified heterozygous rhodopsin gene (RHO) mutation
confirmed by genetic testing (mutations will include P23H, T17M, and R135W).

2. The subject has at least 1 eye that meets all 3 of the following criteria:

1. A measurable EZ area as determined by an evaluation of EZ limits on sdOCT scan,
with a horizontal EZ width of greater than 3 mm

2. BCVA of greater than or equal to 35 letters as measured by the Early Treatment
Diabetic Retinopathy Study (ETDRS; equivalent to 20/200 on a Snellen chart).

3. A kinetic VF of greater than 10 degrees diameter in the horizontal meridian with
a spot size of III

3. The subject has the ability to comply with the clinical protocol, in the opinion of
the investigator.

4. The subject has a clear ocular media and adequate pupillary dilation in both eyes to
permit adequate visual assessments in the opinion of the investigator.

5. The subject has agreed to abstain from any protocol-prohibited medication(s) during
study participation.

6. The subject is medically stable in the opinion of the investigator and able to fulfill
the protocol requirements, including the ability to complete the assessments, without
placing an undue burden on the subject/subject's family.

7. The subject and/or subject's parent(s) or legally authorized guardian(s) has
voluntarily signed an Institutional Review Board (IRB)/ ethics committee (EC)-approved
informed consent and assent form(s), as applicable, after all relevant aspects of the
study have been explained and discussed with the subject and/or the subject's
parent(s) or legally authorized guardian(s).

8. The subject, subject's parent(s), or legally authorized guardian(s) is able to
understand the nature, scope, and possible consequences of the study and agrees to
comply with the protocol-defined, scheduled assessments.

Exclusion Criteria:

1. The subject is participating in an interventional clinical trial or has participated
in an interventional clinical trial within 90 days of screening; participation in
non-interventional observational studies is permitted.

2. The subject has received treatment or has been in the treatment arm of a clinical
trial for gene therapy, stem cell therapy, retinal progenitor cell therapy, tissue
transplantation, device or drug delivery implantation, or other similar invasive
therapy.

3. The subject has any of the following medical conditions that will interfere with
consistent follow-up over any part of the study:

1. Stroke

2. Severe or unstable coronary disease

3. End-stage or aggressive malignancy

4. General poor health or uncontrolled or severe disease (eg, cardiovascular,
neurological, psychological, pulmonary,renal, hepatic, endocrine, or
gastrointestinal disorders) that in the opinion of the investigator would
interfere with participation in the study

4. The subject has any of the following ocular conditions that could interfere with or
confound follow-up of disease progression:

- Glaucoma

- Diabetic retinopathy

- Choroidal neovascularization

- Retinal inflammatory disease

- Cataract worse than grade 2 (nuclear, posterior subcapsular [PSC], or cortical)

- High myopia (≥8 diopters)

- Herpes simplex virus of the eye

- Acute infection or inflammation

- Any ocular condition that in the opinion of the investigator would interfere with
the ability to assess retinal morphology and functionality

5. The subject has had intraocular surgery within 90 days prior to screening.

6. The subject currently requires the following protocol prohibited medications or has
ingested such medication within 30 days of screening:

Plaquenil Thioridazine Clofazimine Deferoxamine Phenothiazine Chlorpromazine Cisplatin
Valproic acid Any other drugs with known visual side effects

7. The subject has 3 first- or second-degree family members already enrolled in the
study.