A multicenter, randomized, double-blind, placebo-controlled clinical trial was designed. The study included two experimental groups (low-dose ZKY001 eye drops group and medium-dose ZKY001 eye drops group) and a placebo control group, with 60 subjects in each group.

Each subject had the study drug instilled into the study eye according to the randomly obtained drug number.

Duration OF THE STUDY：The screening period was D-5 to D-1, the experimental period was D0 (the day of operation) to D5, and the observation period was D10±2.

Statistical analyses were performed with the use of SAS software (version 9.4 or higher) without special instructions. All statistical tests were two-sided, with a significance level of 0.05. Enrollment analysis: the number of enrolled and completed cases in each center was summarized, and the list of dropped cases was made. Overall dropout rates in each group and dropout rates related to adverse events were compared between groups with the use of the chi-square test or Fisher's exact test.

Inclusion Criteria:

1. Age of 18-70 years old, both sexes;
2. patients were diagnosed as primary pterygium with nasal onset, and the head tip of pterygium invaded the cornea ≥3mm and ≤5mm, and underwent pterygium excision combined with conjunctival autotransplantation with autologous limbal stem cells;
3. Except for the pterygium neck under the slit lamp during the screening period, the limbal anatomy was normal without obvious abnormalities (e.g., scar, neovascularization that had invaded the cornea, or pseudopterygium);

Exclusion Criteria:

1. secondary pterygium, recurrent pterygium, pseudopterygium, bilateral pterygium or conjunctival tumor;
2. Schirmer test I (topical anesthesia) ≤3mm/5min;
3. severe blepharitis and/or severe meibomian gland disease, recurrent corneal erosion, chronic corneal disease, chemical burn and other ocular diseases that seriously affect ocular surface structure or function;
4. patients with syphilis, Sjogren's syndrome, cicatricial pemphigoid and other systemic diseases that seriously affect ocular surface structure or function;
5. rheumatoid arthritis, Sjogren syndrome, systemic lupus erythematosus, AIDS and other autoimmune diseases;