An Observational Study of Japanese Participants With X-linked Retinitis Pigmentosa


The purpose of the study is to identify a cohort of Japanese participants with X-linked retinitis pigmentosa (XLRP) associated with pathogenic variants in the retinitis pigmentosa GTPase regulator (RPGR) gene and to investigate their associated phenotype.

Full Title of Study: “Prospective Observational Study to Estimate the Genotype and Phenotype of Japanese Patients With X-linked Retinitis Pigmentosa Associated With Pathogenic Variants in Retinitis Pigmentosa GTPase Regulator (RPGR)”

Study Type

  • Study Type: Observational
  • Study Design
    • Time Perspective: Prospective
  • Study Primary Completion Date: February 28, 2023

Arms, Groups and Cohorts

  • Participants with X-Linked Retinitis Pigmentosa (XLRP)
    • Participants with confirmed diagnosis of XLRP associated with pathogenic variants in retinitis pigmentosa GTPase regulator (RPGR) in the Japanese population will be enrolled in the study and the data will be collected and observed. The primary data source for this study will be the medical records of each participant.

Clinical Trial Outcome Measures

Primary Measures

  • Visual Function
    • Time Frame: Up to Day 30
    • Visual function will be assessed using visual acuity.
  • Retinal Structure
    • Time Frame: Up to Day 30
    • Retinal structure will be assessed using spectral domain optical coherence tomography (SDOCT).
  • Retinal Function
    • Time Frame: Up to Day 30
    • Retinal function will be assessed using static visual field testing.

Participating in This Clinical Trial

Inclusion Criteria

  • Have RPGR-associated retinal dystrophy – Are able to give informed consent or assent, with the guidance of their parent/guardian where appropriate – Are able to undertake age-appropriate clinical assessments as specified in the protocol Exclusion Criteria:

  • Are unable or unwilling to undertake consent or clinical testing – Participated in another research study and had intraocular surgery within 3 months of screening – Significant ophthalmologic diseases

Gender Eligibility: All

Minimum Age: 5 Years

Maximum Age: N/A

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Janssen Pharmaceutical K.K.
  • Provider of Information About this Clinical Study
    • Sponsor
  • Overall Official(s)
    • Janssen Pharmaceutical K.K., Japan Clinical Trial, Study Director, Janssen Pharmaceutical K.K.
  • Overall Contact(s)
    • Study Contact, 844-434-4210,

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