In vivo evaluation of azapropazone cyclodextrin complexes from ophthalmic formulations/ocular tolerance and disposition in eye tissues

Document Type : Original Article

Authors

1 Department of Pharmaceutics, Faculty of Pharmacy, Mansoura University Mansoura,35516, Egypt

2 Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Egypt

Abstract

The effect of inclusion complex formation of azapropazone (Az) with cyclodextrins (CyDs)​, hydroxypropyl β-​cyclodextrin (HP-​β-​CyD) and β-​cyclodextrin (β-​CyD) on the bioavailability of the drug in rabbits eye tissues (conjunctiva, cornea, iris-​ciliary body and aq. humor) front ophthalmic prepns. (drops, gels and inserts) contg. the drug or its complexes were studied.  The solid inclusion complexes of Az were prepd. by the kneading method in molar ratios of 1:1 (guest​/host) with HP-​β-​CyD or β-​CyD.  The prepd. complexes were investigated by the soly. method.  The enhancing effect of HP-​β-​CyD on the penetration of Az in various eye tissues was greater than that of β-​CyD.  The in-​vivo availability of Az from the tested ophthalmic prepns. in eye tissues were arranged as following; conjunctiva > cornea > iris-​ciliary body > aq. humor.  The peak time of Az for all formulations in the various eye tissues was 4 h.  Meanwhile, AUCs of total drug disposition in the different eye tissues were 617.4, 882.4, 993.5, 1292.7, 1462.6, 1968.2 and 2141.3 μg. h​/g for Az drops, Az gel, Az inserts, Az-​β-​CyD gel, Az-​β-​CyD inserts, Az-​HP-​β-​CyD gel and Az-​HP-​β-​CyD inserts, resp.  The disposition of the drug in eye tissues showed that the distribution was greatly affected by the presence of CyDs.  Moreover, the uptake of Az by different eye tissues was quite different from the selected formulations.