The purpose of this study is to determine whether SYL1001 ophthalmic solution is safe and effective in the treatment of signs and symptoms of Dry Eye Disease.

Inclusion Criteria:

• Both genders
• ≥ 18 years old
• Give written informed consent to participate in the study after having been informed of the study design, objectives and possible derived risks
• Common symptoms of persistent, daily, moderate to severe dry eye lasting more than six months.
• Use of artificial tears
• VAS scale for eye discomfort/pain between 30 - 80
• CFS ≥ 2 and ≤ 4 on the Oxford scale
• TBUT < 10 seconds
• Hyperemia score ≥ 1 (McMonnies scale)
• Schirmer's test without anesthesia ≥ 2 and < 10 mm/5min in the eye
• Corrected visual acuity ≥ 0.7 logMAR

Exclusion Criteria:

• Pregnant or breastfeeding females or those with a positive pregnancy test.
• Females of childbearing potential who will not use a medically acceptable contraceptive method from selection and during the whole study.
• Current relevant disease, including respiratory disease, cardiovascular, endocrine, neurological, haematological, renal, neoplasic, hepatopathy, gastrointestinal distress, hypertension, or infectious acute processes.
• Past history of a chronic o recurring condition that could interfere with study according to the investigator's judgement.
• Concomitant use of other drugs with analgesic activity by any route of administration at the enrolment period.
• Changes in any ocular and/or systemic concomitant medication one month prior to the study commencement and during the study development.
• Changes on the preestablished artificial tears dosage 15 days prior to the study commencement and during the study development.
• Cyclosporine treatment initiation or changes in cyclosporine dosage or dosing regimen during the 6 months prior to enrolment.
• Previous history of drug hypersensitivity.
• Use of contact lenses
• Case history of drug or alcohol abuse or dependence.
• Relevant abnormal laboratory results as judged by the investigator
• Previous refractive surgery
• Participation in a clinical trial within 2 months before the enrolment visit
• Relevant ocular pathology judged by the investigator.