Cyclosoprin A (CYA) has been shown to be a potent immunosuppressive drug, and it has been administered as eye drops for penetrating keratoplasty and severe allergic conjunctivitis. In this study, we investigated the pharmaceutical characteristics of 0.05 % CYA aqueous eye drops using α-cyclodextrin as a solvent (CYA-CD eye drops) and their topical application for uveitis and scleritis in the clinical setting.
The pH of the CYA-CD eye drops was about 5.1 and in dark storage at 4°C for a period of 10 months from preparation, there was no change in pH or the CYA concentration of the CYA-CD eye drops. When the partition coefficients of CYA were measured in 1-octanol/water, this parameter (log Poct/w) was 2.16 for the CYA-CD eye drops. This value is similar to those for CYA in the literature showing that the release behavior of CYA in the CYA-CD eye drops was not influenced by CD. Therefore, the CYA in CYA-CD eye drops would be rapidly taken up by the cornea.
When the CYA-CD eye drops were clinically applied in 12 patients with uveitis and scleritis, they were effective in 10 patients enabling them to reduce the dosage of steroid eye drops they were taking or stop using them altogether, showing that CYA-CD eye drops are effective for these conditions.
