Abstract: Objective  To observe the short term effect basing  on the  signs of mild to moderate dry eye with 3% diquafosol sodium eye drops treatment. Design Multi-center, single-arm prospective phase Ⅳ clinical trial. Participants  2660 dry eye patients from 30 Eye Centres. Methods Patients with dry eye symptoms, positive corneal fluorescein staining (CFS), tear film breakup time (BUT）≤5 s or Schirmmer I test (SIt) ≤10 mm/5min were treated only with 3% diquafosol sodium eye drops 6 times a day. One of the eyes was selected for analyzed. CFS, BUT, slit lamp microscopy, SIt and other examinations at 3 visits of baseline, 2 weeks and 1 month of treatment were recorded. CFS improvement compare to baseline according to SIt and BUT grouping ; BUT improvement compare to baseline according to SIt and CFS grouping; SIt improvement compare to baseline according to BUT and CFS grouping were recorded. Main Outcome Measures CFS, BUT, SIt during at baseline,  2 weeks and 1 month of treatment were recorded. Results At 2 weeks and 1 month of treatment with 3% diquafosol tetrasodium eye drops, the differences of  changes of  BUT, CFS and SIt from the baseline in different age groups were all statistically significant respectively (all P<0.05). Subgroup divided according to degree of baseline SIt and BUT,  CFS improvement has no statistical significant difference among  groups at 1 month (all P>0.05). When subgroup divided according to degree of baseline SIt and CFS, while SIt≤5 mm/5min or SIt >10 mm/5min, BUT improvement is higher in  group of CFS 6-10 than group of CFS 1-5 (P<0.05) at 1 month; while SIt >5 plus ≤10 mm/5min, BUT improvement  is higher in CFS 1-5 group than CFS 6-10 group (P<0.05). While CSF 1-5, BUT improvement is higher in SIt≤5 mm/5min group than  SIt >5 plus ≤10 mm/5min  and SIt >10 mm/5min groups (P<0.05). When subgroup divided according to degree of baseline BUT and CFS at 1 month, while CFS 1-5, SIt improvement is higher in BUT>5 s group than  BUT≤5 s group (P<0.05). While BUT ≤5 s, SIt improvement is higher in CSF 1-5 group than CSF 6-10 group (P<0.05). Conclusion 3% diquafosol tetrasodium eye drops is effective in the treatment in different age groups. BUT improvement is affected by baseline SIt and CFS after 3% diquafosol tetrasodium eye drops treatment. Poor baseline SIt  won’t limit the improvement  of  CFS or BUT for mild and moderate dry eyes. (Ophthalmol CHN, 2022, 31: 305-311)

Key words: dry eyes, diquafosol tetrasodium eye drops