Phase 3 Clinical Study of UF-021 for Retinitis Pigmentosa - Evaluation for a Comparative Double Masked Placebo Controlled Study Period and a Continuous Administration Period

INTERVENTION: investigational material(s) Generic name etc : UF‐021(isopropyl unoprostone) INN of investigational material : Therapeutic category code : 131 Agents for ophthalmic use Dosage and Administration for Investigational material : Eye drop CONDITION: Retinitis Pigmentosa PRIMARY OUTCOME: ‐ Efficacy : Retinal sensitivity; ‐ Safety SECONDARY OUTCOME: Efficacy : Other retinal sensitivities, visual acuity, VFQ‐25, visual field area, OCT test. INCLUSION CRITERIA: 1)Medical examination classification: Outpatients 2)Observation, examination, and surveillance in accordance with the study protocol are judged to be feasible. 3)ETDRS visual acuity test is judged to be feasible at a distance of 4 meters. 4)HFA (10‐2) test is judged to be feasible by investigator. 5)Goldmann perimetry shows concentric central visual field loss (including a ring scotoma) with the central 30 degrees or less. 6)The difference in the mean retinal sensitivity at four central points must be less than 3 dB between two measurements with HFA (10‐2) conducted within 31 days and both values are worse than 30 dB. (When this criterion is not met after two tests, a 3rd measurement will be implemented.)