Assess the Safety and Efficacy of CsA Ophthalmic Gel in Subjects With Moderate to Severe Dry Eye Disease

A multicenter,randomized, double-blind, vehicle-controlled Study.Subjects will be randomly assigned to the experimental group and the control group,experimental group: CsA eye gel: 0.3 g: 0.15 mg, once daily;One drop into each eye when you use it.hypromellose eye drops:10ml：50mg,three times a day Control group: vehicle. One drop into the eye, once daily;One drop into each eye when you use it.hypromellose eye drops:10ml：50mg,three times a day

Inclusion criteria

1）18≤Age≤80, both male and female 2）According to the symptoms and signs and ophthalmologic examinations, the patients were diagnosed as moderate to severe dry eye

• EDS score is more than 40 points;
• BUT is less than 10 s;
• Schirmer test result is less than 10mm/5 min;
• ICSS≥2 points. 3）The ICSS score of baseline decreased by≤ 20% compared with that of screening period 4）Agree to participate in the study and voluntarily sign informed consent.

Exclusion criteria

• Severe dry eye patients requiring surgical treatment
• Had inner eye surgery within 12 months prior to screening or required inner eye surgery during the study period;Eyelid surgery was performed within 6 months prior to screening
• Patients receiving permanent lacrimal insertion or patients receiving temporary lacrimal insertion within 6 months prior to screening;
• Operation-induced dry eye
• Glaucoma patients;
• Unwilling to avoid wearing contact lenses;
• Systemic inflammation or active eye infection and blepharitis;
• Patients with multiple episodes of viral keratitis
• Patients with ocular cicatricial pemphigoid, obvious conjunctival scar, ocular chemical burn and neurotrophic keratoconjunctivitis
• Patients with malignant tumors in the past 5 years, except the thoroughly cured basal cell carcinoma of skin, squamous cell carcinoma in situ of skin, and primordial cervical cancer;
• Perimenopausal women are taking hormone replacement therapy
• Patients who cannot stop using other eye drops and other ophthalmic preparations during the study period;
• Patients with severe cardiopulmonary diseases, uncontrolled hypertension and diabetes, etc. that affect the collection or compliance of study parameters;
• ALT and AST ≥ 2 times of the normal upper limit, and serum creatinine ≥ 1.5 times of the normal upper limit
• With a history of central nervous system disease or epilepsy, and/or a mental state that does not cooperate
• Pregnant women and lactating women, or women of childbearing age, do not adopt effective contraceptive measures;
• Participated in other clinical trials or participated in other clinical trials within 1 months before the election;
• Systemic or topical cyclosporine drugs within 1 months before the election;
• Allergy to CsA, fluorescein or any component of the drug is known；
• Patients who were not considered suitable for the study, including those who were unable or unwilling to comply with the protocol requirements.