Objective: To study the drug concentration in the aqueous humor and the biocompatibility of cyclosporine A drug delivery system (CsA DDS) implanting in the anterior chamber.
Methods: There were four different types of CsA DDS which had different biodegradable polymers as the vector or had different ratio between CsA and the vector. Thirty-six New Zealand rabbits were randomly divided into 4 groups to receive the 4 different types of CsA DDS. Three of nine New Zealand rabbits received CsA DDS in one eye and empty DDS in the contralateral eye. Three rabbits received empty DDS in one eye and keratotomy in the contralateral eye. Another three rabbits received CsA DDS in one eye and keratotomy in the contralateral eye. All DDS were implanted into the anterior chamber. The follow-up period was 12 weeks.
Results: No significantly acute or chronic intraocular toxic effects were found in all groups. The CsA release rate was different in these 4 groups. In type A and B CsA DDS, the drug released fast and maintained for a short period; in type C and D, the drug released slowly and could be maintained for a long period.
Conclusion: CsA DDS implanted in the anterior chamber can be well tolerated in rabbit eyes. CsA DDS is a promising approach for the prevention (type C and D CsA DDS) and treatment (type A and B CsA DDS) of corneal graft rejection.