Safety and efficacy of intracapsular tranilast microspheres in experimental posterior capsule opacification.
OBJECTIVE
To evaluate the safety and efficacy of a sustained-release agent designed to reduce posterior capsule opacification (PCO).


METHODS
Department of Ophthalmology, EENT Hospital, Fudan University, Shanghai, Peoples Republic of China.


METHODS
Free tranilast (TFree) was incorporated into polylactic acid microspheres and then tested using a rabbit model of PCO. Twenty-nine rabbits were randomized into 5 groups treated with balanced saline solution (BSS control); TFree; or 0.5, 1.0, or 2.0 mg tranilast microspheres (TMicro). Standard phacoemulsification cataract surgery, including manual aspiration of all visible soft lens matter, was performed in all groups. The selected test agent was then injected into the lens capsule. Postoperative clinical examinations were performed at 1, 3, 7, 14, 30, 60, and 90 days. Posterior capsule opacification was quantified using high-resolution computer image analysis at 1, 2, and 3 months. Histological examination was performed at 3 months.


RESULTS
Eyes treated with TMicro had significantly less PCO than the eyes in the BSS and TFree groups. While the BSS control eyes had increased PCO over 3 months, eyes in the TMicro group had reduced PCO over time in a dose-dependent fashion. Histological examination showed reduced lens epithelial cell proliferation in the TMicro groups, with no manifest damage to the cornea, iris, or retina compared with the BSS controls. There was a transient increase in postoperative inflammation in all tranilast-treated groups compared with the BSS controls.


CONCLUSIONS
Sustained-release intracapsular tranilast reduced PCO in an experimental model of PCO, suggesting further investigation of its therapeutic potential is justified.
Department of Ophthalmology, EENT Hospital, Fudan University, Shanghai, Peoples Republic of China. gwman2003@yahoo.com.cn
Man
M
Wang
Jin-Jun
JJ
Zhang
Timothy L
TL
Jackson
Xinghuai
X
Sun
Wei
W
Wu
John
J
Marshall
D000818:Animals; D018926:Anti-Allergic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D002386:Cataract / Q000188:drug therapy* / Q000473:pathology; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000009:adverse effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D007267:Injections; D007903:Lens Capsule, Crystalline / Q000187:drug effects* / Q000473:pathology; D008297:Male; D008863:Microspheres; D018918:Phacoemulsification; D011183:Postoperative Complications; D011817:Rabbits; D013997:Time Factors; D016896:Treatment Outcome; D062367:ortho-Aminobenzoates / Q000008:administration & dosage* / Q000009:adverse effects
D018926:Anti-Allergic Agents; D003692:Delayed-Action Preparations; D062367:ortho-Aminobenzoates; C012293:tranilast