Comparative Study to Evaluate ISV-305 Compared to Vehicle in Blepharitis Subjects

Inclusion Criteria: * Are at least 1 years of age and have a clinical diagnosis of active, symptomatic blepharitis * Signature of the subject or parent(s) or legally authorized representative on the Informed Consent Form, and when appropriate the minor's assent in accordance with local regulations * Are willing and able to follow all instructions and attend all study visits (this applies to parent or caregiver for subjects too young to self-apply investigational product) * Are willing to avoid disallowed medication for the duration of the study * If female is of childbearing potential, agree to and submit a urine sample for pregnancy testing (prior to enrollment and at the end of the study) and use effective contraception for the duration of the study * Male subjects whose female partners are not post-menopausal must agree to one of the following: 1) completely abstain from sexual intercourse, 2) use a barrier method (condoms) with spermicide during sexual intercourse for the duration of the study, 3) provide documentation for having had a vasectomy (with documented infertility) * Additional inclusion criteria also apply Exclusion Criteria: * Have known sensitivity or poor tolerance to any component of the study drugs * Have had eyelid surgery in the study eye within twelve (12) months prior to Visit 1 or plan to have eyelid surgery during the study * Have an acute ocular infection (bacterial, viral or fungal) or active ocular inflammation other than blepharitis in the study eye * Have used topical medications on the eyelids or topical ophthalmic corticosteroid medications or systemic use of a corticosteroid mediation within 14 days prior to dosing and/or plan to use them throughout the duration of the study * Be currently pregnant, nursing, or planning a pregnancy; or be a woman who has a positive urine pregnancy test * Have prior (within 30 days prior to dosing) or anticipated concurrent use of an investigational drug or device * Have a condition or a situation which, in the investigator's opinion, may put the subject at increased risk, confound study data, or interfere significantly with the subject's study participation * Additional exclusion criteria also apply