Efficacy of Standardized and Quality-Controlled Cord Blood Serum Eye Drop Therapy in the Healing of Severe Corneal Epithelial Damage in Dry Eye

Abstract

We standardized quality-controlled cord blood serum (CBS)-based eye drops and evaluated the efficacy of 1-month CBS treatment in the healing of diseased corneal epithelium in severe dry eye (DE) patients. Seventeen graft-versus-host disease (GVHD) and 13 Sjogren syndrome patients with severe persistent corneal defects were enrolled in the framework of a registered clinical trial (ClinicalTrials.gov NCT01234623). Sterile CBS eye drops were prepared to supply 0.15 ng per eye per day epithelial growth factor and administered for 1 month in a 1-day dose dispensing. The extent of epithelial defect was evaluated in square millimeters area, and subjective symptom score (Ocular Surface Disease Index score), Schirmer test I, break-up time, tear osmolarity, corneal esthesiometry (Cochet-Bonnet esthesiometer), conjunctival scraping, and imprint cytology with goblet cell count were performed at baseline (V0) and after 15 (V1) and 30 (V2, endpoint) days of treatment. Satisfaction and tolerability questionnaires were evaluated at V1 and V2. A significant reduction was shown at the endpoint versus baseline in corneal epithelial damage (mean ± SD, 16.1 ± 13.7 vs. 40.9 ± 30 mm²/area, respectively), discomfort symptoms (Ocular Surface Disease Index score, 22.3 ± 10.3 vs. 39.3 ± 16.9), scraping cytology score (3.8 ± 1.2 vs. 6.6 ± 2.1), and tear osmolarity (312.5 ± 7 vs. 322 ± 9.1 mOsm/L), whereas a significant improvement was shown in corneal esthesiometry (48.2 ± 2.1 vs. 49.7 ± 2.1 nylon/mm/length, P < 0.05). All patients reported a high degree of satisfaction upon drop instillation. Heterologous CBS-based eye drops represent a promising therapeutic approach in the healing of severely injured corneal epithelium and in subjective symptom relief. These drops can be obtained as readily available and quality-controlled blood derivative from cord blood banks on a routine basis.