A Study to Evaluate the Clinical Efficacy and Safety of Tobradex® ST Compared to Azasite® in the Treatment of Subjects With Moderate to Severe Chronic Blepharitis

Inclusion Criteria: * Have diagnosis of moderate to severe chronic blepharitis defined by a minimum score of at least "1" for one of the lid signs, one of the conjunctival signs, and one of the symptoms in at least one eye * Have a minimum global score (the total signs and symptoms score) of 5 in the same eye qualifying. Exclusion Criteria: * Have known sensitivity or poor tolerance to the test article (tobramycin, dexamethasone, azithromycin) or its components or any therapy associated with the trial * Have a history of ocular surgical intervention within six (6) weeks prior to Visit 1 or during the study * Have any ocular infections (bacterial, viral or fungal) - active ocular inflammation (i.e. follicular conjunctivitis, iritis) or preauricular lymphadenopathy, other than blepharitis * Have worn contact lenses in the 72 hours prior to visit 1 and for the duration of the study * Are currently taking any medication known to cause ocular drying that has not been on a stable dose for at least 30 days * Have used any topical ocular or systemic antibiotics within 7 days of enrollment. Stable (greater than 1 month prior to enrollment) use of topical antibiotics on the face (except around the eyes) for dermatologic conditions is allowed. Dose must continue unchanged for duration of study * Have used any topical ocular - aerosolized/nebulized - or systemic corticosteroid agents within 14 days of enrollment. Stable (greater than 1 month prior to enrollment) use of inhaled (using …