A Study to Evaluate Corneal Endothelial Cell Density (ECD) in Subjects With Dry Eye Disease (DED) Administering Miebo® (Perfluorohexyloctane Ophthalmic Solution) for 12 Months.

Inclusion criteria

• Be at least 18 years of age at the time of consent.
• Have a self-reported history of DED in both eyes (OU) for at least 6 months prior to Visit 1 (Screening/Baseline)
• Have a total corneal fluorescein staining score (tCFS) score >2 in both eyes
• Have an Ocular Surface Disease Index (OSDI) score >17
• Have a baseline ECD ≥1750 cells/mm2 in each eye
• Provide written informed consent
• Be able and willing to follow instructions, including participation in all trial assessments and visits
• If a contact lens wearer, be willing to discontinue contact lens use during and for 30 minutes following instillation of investigational drug and during study visits

Exclusion criteria

• Be at least 18 years of age at the time of consent.
• Have a self-reported history of DED in both eyes (OU) for at least 6 months prior to Visit 1 (Screening/Baseline)
• Have a total corneal fluorescein staining score (tCFS) score >2 in both eyes
• Have an Ocular Surface Disease Index (OSDI) score >17
• Have a baseline ECD ≥1750 cells/mm2 in each eye
• Provide written informed consent
• Be able and willing to follow instructions, including participation in all trial assessments and visits
• If a contact lens wearer, be willing to discontinue contact lens use during and for 30 minutes following instillation of investigational drug and during study visits
• Have any clinically significant ocular surface slit lamp findings and/or in the opinion of the Investigator have any findings that may interfere with trial parameters in either eye
• Have an ocular or periocular malignancy in either eye
• Have a history of herpetic keratitis in either eye
• Have any planned ocular and/or lid surgeries in either eye during the course of the study
• Have a known allergy and/or sensitivity to the IP
• Have a history of ocular laser surgery in either eye within 3 months (90 days) prior to Visit 1 (Screening/Baseline)
• Have a history of incisional ocular surgery or severe trauma in either eye within 3 months (90 days) prior to Visit 1 (Screening/Baseline)
• Have high contrast best-corrected visual acuity equal to or worse than logMAR +0.7 (Snellen equivalent score of 20/100 or worse) as assessed by Early Treatment Diabetic Retinopathy Study (ETDRS) scale in either eye, obtained under bright room lighting
• Be a woman who is pregnant, nursing or planning a pregnancy during the course of the study
• Be a woman of childbearing potential who is unwilling to submit to a urine pregnancy test. Non-childbearing potential is defined as a woman who is permanently sterilized (eg, has had a hysterectomy or bilateral tubal ligation or bilateral oophorectomy) or is postmenopausal (without menses for 12 consecutive months).
• Be a woman of childbearing potential who is not using an acceptable method of birth control. Acceptable methods of contraception include hormonal - oral, implantable, injectable, or transdermal - contraceptives; mechanical contraception - spermicide in conjunction with a barrier such as a diaphragm or condom; intrauterine device; or surgical sterilization of partner. For non-sexually active females, abstinence may be regarded as an adequate method of birth control; however, the subject must agree to use adequate birth control as defined above for the remainder of the study if she becomes sexually active during the trial.
• Be currently enrolled in an investigational drug or device trial or plan to enroll during the course of the study
• Have a condition or be in a situation that the Investigator believes may put the subject at significant risk, may confound the study results, or may interfere significantly with the subject's participation in the study