CURRENT AND FUTURE MANAGEMENT OF RETINITIS PIGMENTOSA

    Retinitis pigmentosa (RP) is a progressive inherited retinal disease, and patients with RP have reduced visual function caused by a degeneration of the photoreceptors and retinal pigment epithelium (RPE).

    Our studies using OCT have demonstrated that the presence of and continuity of the IS/OS line is associated with good visual function in RP patients. This can be also applied to predict postoperative visual acuity in RP patients after cataract surgery. Fundus autofluorescence (FAF) results from the accumulation of lipofuscin in the RPE cells and has been used to investigate RPE and retinal function. We have reported that more than one-half of RP patients have an abnormally high density parafoveal FAF ring (AF ring). The AF ring represents the border between functional and dysfunctional retina. By combining these new methods, morphological and functional assessments of the photoreceptors in the macula area can be more precise in RP patients. A Phase 2 clinical trial completed in Japan showed that unoprostone eye drops improve or maintain the central retinal sensitivity in RP patients. We have already started a Phase 3 clinical trial in Japan in which 200 patients have been randomized into 2 groups: high-dose and placebo groups. The primary endopoint of P3 is the central retinal sensitivity measured with HFA. All patients will be followed for 52 weeks. The key-open is scheduled within this year.