Anterior Drug Delivery

 

Anterior Segment Drug Delivery

 

 
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Background

The vast majority variety of ocular diseases, including glaucoma, dry eye, allergic conjunctivitis, bacterial infections and others, are currently treated with eye drops. Most of these anterior segment diseases require drug dosing via eyedrops 3-4 times a day, with severe infections needing antibiotic dosing at 15-30 minute intervals.  In the case of chronic diseases such as glaucoma, daily dosing is required for the life of the patient.

The anatomical and physiologic uniqueness of the eye and its built-in mechanisms of defense make targeting ocular tissues with drugs one of the greatest challenges in drug delivery.  It is estimated that only 5% or less of the drug that leaves the bottle becomes pharmaceutically bioavailable. This lack of efficiency is problematic for diseases of the anterior surface, but crippling if the intended delivery is for posterior segment disease as residence times are too short for sufficient drug to be absorbed. A viable alternative to drop delivery would be widely acceptable to clinicians and patients with ocular surface disease.
 
The high turnover rate of the aqueous layer of the tear film, designed to protect the delicate ocular structures, also leads to significant loss of drug. While the turnover of the tears is extremely rapid, on the order of minutes depending on the blink rate, the mucin layer covering the corneal epithelium lasts much longer - on the order of a day or more. Nanomedicines which interact with the mucin layer have significant potential to enhance corneal residence time and delivery to the eye as mucins stick to chemically similar compounds, such as other mucins. The adhesive nature of mucosal surfaces has made them attractive targets for drug delivery.

 

Methodology 

Specifically, we will: 

  1. Development poly(phenylboronic acid) containing nano materials for drug delivery  
  2. Perform in vitro drug release and characterization
  3. Perform in vivo evaluation of promising formulations