Abstract
Purpose:
The purpose of this study was to evaluate the safety and efficacy of thymosin beta 4 (Tβ4) eye drops as a novel therapy for severe dry eye disease (including Graft vs Host Disease) in a double-masked, vehicle-controlled, physician-sponsored Phase 2 clinical trial. The study’s hypothesis is that Tβ4, in its role as a modulator of corneal surface healing and inflammation, may be able to promote healing of the corneal surface allowing for more conventional modalities to take over and maintain a smooth and regular ocular surface.
Methods:
Nine patients with severe dry eye (18 eyes) were treated with Tβ4 drops (0.1%) or vehicle control six times daily over a period of 28 days. They were evaluated upon entering the study after a two week washout period as follows: Study Day 1 (randomization and first day of treatment), 7, 14, 21, 28 (End of Treatment), and 56 (follow-up). Dry eye sign and symptom assessments, such as ocular discomfort (using the OSDI questionnaire) and corneal fluorescein staining (using the NEI workshop grading system), were evaluated at various time points throughout the study.
Results:
Statistically significant differences in sign and symptom assessments, such as ocular discomfort and corneal fluorescein staining, were seen at various time points throughout the study. Of particular note at Day 56, the follow-up period, were the differences between Tβ4 and vehicle control. The Tβ4-treated group (12 eyes) had a 35.1% reduction of ocular discomfort compared to vehicle control (6 eyes) (p=0.0141), and a 59.1% reduction of total corneal fluorescein staining compared to vehicle control (p=0.0108). Other improvements seen in the Tβ4-treated patients included tear film breakup time and increased tear volume production.
Conclusions:
Tβ4 eye drops were found to be safe and well-tolerated and met key efficacy objectives with statistically significant sign and symptom improvements, compared to vehicle control, at various time intervals, including 28 days post-treatment. These positive results suggest that further clinical trials are warranted and should aim to assess Tβ4’s efficacy and optimal dosing regimens in the setting of severe dry eye disease.
Keywords: 466 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials •
486 cornea: tears/tear film/dry eye •
765 wound healing