Abstract
Purpose :
Subjects with DED frequently report visual function disturbances despite normal visual acuity measurement. We performed a post-hoc correlation analysis on data from 2 independent randomized, double-masked, vehicle-controlled Phase 2 and Phase 2b/3 clinical trials in DED subjects to investigate the correlation of corneal fluorescein staining with several dimensions of visual function.
Methods :
All randomized subjects from clinical trials CYS-003 (NCT03292809) and NVU-002 (NCT03333057) with at least one data pair of corneal staining score ( total corneal fluorescein staining, NEI scale, scoring range 0-15) and visual function parameter (subjective assessments of blurred vision, poor vision, reading, driving at night, working with computer/ATM, and objective measurements of reading speed [performed in CYS-003 only]) were included in the analysis. All analyses were performed irrespective of the assigned treatment. To adjust for multiple data pairs per subject, a mixed effect modelling analysis was conducted for each trial, using the nonlinear mixed effects modelling tool NONMEM.
Results :
664 subjects were included in the analysis (CYS-003: N=328; NVU-002: N=336) with data pairs (corneal staining/visual function) from assessments recorded at up to 5 time points over a period of 8 to 12 weeks.
In CYS-003, corneal staining correlated statistically significantly (p<0.001) with all subjective assessments, as well as with low contrast and low print-size reading speed. In NVU-002, total corneal staining correlated statistically significantly (p<0.001) with subjects’ self-reported levels of blurred and poor vision, difficulties with reading, and inversely with driving at night (p=0.016).
A reduction of 3 units in total corneal fluorescein staining lead to an estimated improvement in subjective visual function in the range of 5.2 to 13.5% in CYS-003, and of 13.4 to 15% in NVU-002. The estimated improvement in reading speed with low contrast and with low print size reading material in CYS-003 is 4 wpm (3.6%) and 6 wpm (4.7%), respectively.
Conclusions :
Total corneal fluorescein staining correlates significantly and clinically meaningful with both subjective and objective functional parameters of visual function in subjects with DED. The impact on reading speed increases with visually straining tasks.
This is a 2020 ARVO Annual Meeting abstract.