Purpose:
DSM’s amino acid-based polyesteramides (‘PEAs’) are being developed as a novel degradable biomaterial for applications in ocular drug delivery. PEAs are highly versatile with respect to physico-chemical properties and processability, and hold promise as a multi-month sustained release delivery system. Biodegradation and inflammatory response is tested by subconjunctival and intravitreal implantation into rabbit eyes.
Methods:
PEAs are based on α-amino acids, aliphatic dicarboxylic acids and aliphatic α-ω diols. These PEAs have been processed into fibrils with a fluorescent dye. In Biodegradation and initial tissue response are assessed by clinical photo-documentation, fluorescent microscopy and histological examination based on H&E staining.
Results:
PEAs have been processed into fibrils of approximately 100 µm diameter for delivery through small gauge needles (≤ 26G) to subconjunctival and intravitreal spaces. PEAs degrade enzymatically as demonstrated in vitro with chymotrypsin, esterases, lipases as well as macrophage meditated degradation. In-vivo degradation profiles and tissue response of fibril implants are on-going.
Conclusions:
Amino acid based biodegradable polymers represent a next generation platform for sustained release drug delivery and hold promise for utility in ophthalmology.
Keywords: injection • vitreous • development