Safety and Efficacy of Stem Cell Small Extracellular Vesicles in Patients With Retinitis Pigmentosa

Inclusion Criteria: * Age 18 years or above * Clinically diagnosed with RP by experienced ophthalmologists or having documented mutations in the genes responsible for RP * Central visual field in the better eye less than or equal to 20 degrees * Best corrected visual acuity (BCVA) in the worse eye 6/18 (logMAR 0.48) to 6/120 (logMAR 1.3) by Snellen visual acuity chart * Electroretinogram in the worse eye nonrecordable or the amplitudes were less than 25% of normal * Willing and able to give informed consent for participation in the study Exclusion Criteria: * Intolerance and/or contraindication to local anesthesia and other substances used during the procedure * Pregnant or lactating woman * Having blood-borne infections, i.e. Human immunodeficiency virus (HIV), hepatitis B or C, Human T-lymphotropic viruses (HTLV) * Having any other significant ocular or non-ocular disease/disorder which may either put the subjects at risk because of participation in the study, or may influence the results of the study, or the subjects ability to participate in the study. This includes 1. Inherited or acquired bleeding disorders, including the use of anticoagulant medications that cannot be stopped prior the procedure 2. Autoimmune diseases, i.e., systemic lupus erythematosus, multiple sclerosis, fibromyalgia, Guillain-Barre syndrome 3. Severe/uncontrolled chronic/metabolic diseases, e.g., diabetes mellitus, cardiovascular disease, chronic kidney disease, transient ischemic attack (TIA)/stroke * Unable to complete the full course of the study or failed to return for follow up