The correlation between ocular surface inflammation and corneal fluorescein staining (CFS) in patients with moderate to severe dry eye disease (DED) participating in a randomized clinical trial

Purpose The relationship between ocular surface inflammation, signs and symptoms in DED remains poorly understood. A correlation between ocular surface inflammation and CFS in DED patients is reported. Methods DED patients with tear break up time ≤8 seconds and CFS grades 2‐4 modified Oxford scale and Schirmer test without anesthesia ≥2 and <10 mm/5min and lissamine green staining, Van Bijsterveld >4 and at least 1 dry eye symptom were randomized to CYCLOKAT® (unpreserved 0.1% cyclosporine cationic emulsion) or vehicle QD. Impression cytology for conjunctival HLA‐DR expression (an ocular surface inflammatory biomarker) was performed in a subset of patients. Results Cytology samples were collected in 89 of 492 patients. At baseline the mean HLA‐DR expression was higher in the CYCLOKAT® (84,345 AUF vs 46,888 AUF) arm. Notably, the mean HLA‐DR expression increased with baseline CFS grade (grade 2: 48,343; grade 3: 56,749; grade 4: 127,623). At month 6, CYCLOKAT® significantly reduced the HLA‐DR expression (‐50896 AUF vs ‐1192 AUF, p=0.022). The efficacy of CYCLOKAT® on improving CFS [as measured by mean change (delta of CYCLOKAT® over vehicle) and % achieving ≥ 2 grade improvement] increased with the CFS grade at baseline (grade 2‐4: 0.22 and 33.6% vs 21.8%, grades 3‐4: 0.32 and 40.4% vs 27.7%, grade 4: 0.77 and 48.8% vs 19.5%, p<0.05 for all comparisons). Conclusion The demonstrated correlation between HLA‐DR expression and CFS support the role of inflammation in DED and justifies the need for anti‐inflammatory therapy. The benefit of CYCLOKAT® appears to be greatest in patients with severe DED.Commercial interest