The study purpose is to evaluate the efficacy and safety of cultivated oral mucosal epithelial sheet transplantation as a novel therapy for limbal stem cell deficiency, for which no effective approaches has thus far been available, for the purpose of establishing this therapy as an effective strategy for this disease with an aim of improving visual acuity and corneal transparency.

The efficacy and safety of cultivated oral mucosal epithelial sheet transplantation as a novel therapy for limbal stem-cell deficiency, for which no effective approaches have thus far been available, will be evaluated for the purpose of establishing this therapy as an effective strategy for this disease with an aim of improving visual acuity and corneal transparency. The primary endpoint will be an area of no conjunctivalization and no corneal epithelial defect at one year, which will be evaluated according to a 6-grade rating scale. The secondary endpoints will be corrected visual acuity, severity of corneal opacification, extent of corneal neovascularization, expected ocular complications, and all adverse events including abnormal laboratory findings. The purpose of this research is to evaluate the efficacy of the investigational therapy so as to provide rationales for making this strategy approved as an advanced medical care in the future.

Inclusion Criteria:

• Among patients with bilateral limbal stem-cell deficiency, those who meet all the criteria listed below when they give their informed consent to participate in this research will be included.

  1. Patients in whom the eye(s) (subject to the interventional therapy) show(s) loss or dysfunction of corneal epithelial stem cells throughout the total* circumference of the cornea
  2. Patients in whom the corneal surface of the eye(s) (subject to the investigational therapy) is(are) entirely enveloped by conjunctival tissue
  3. Patients of both genders aged ≥20 years when they give their informed consent
  4. Patients who have given their own written consent to participate in this clinical research (The target disease is bilateral limbal stem-cell deficiency, although it is not always necessary that the both eyes of the patient meet the inclusion criteria.)

Exclusion Criteria:

1. Patients who are or may be pregnant, and patients who are breast feeding
2. Patients with infections (HBV, HCV, HIV, HTLV-1)
3. Patients with extreme hypolacrimation resistant to therapy
4. Patients from whom oral mucosal specimens cannot be collected because clear scar formation or inflammatory findings are noted in a cell-collection site of the mucosal membrane
5. Patients whose score of Performance Status (PS*) is 3 or more
6. Any others who are judged by the chief subinvestigator to be ineligible for this clinical research, due to the presence of complications, etc.