Abstract
Purpose :
Treatment of uveitis often require prolonged intensive topical steroid therapy. Liposomes can deliver steroids to inflamed ocular tissue and provide sustained drug delivery. We conducted a study to evaluate the efficacy of a single dose of subconjunctival liposomal triamcinolone acetonide (TA) compared to intensive topical steroid therapy for the treatment of uveitis using a rabbit model of experimental uveitis.
Methods :
Experimental uveitis was induced by unilateral intravitreal injection of Mycobacterium tuberculosis H37Ra antigen (50ug; 1ug/uL) in preimmunized New Zealand White rabbits. Rabbits were randomized into 3 groups and given one of the following intervention 4 days after uveitis induction: a single dose of 0.1ml liposomal TA (4mg/ml) given subconjunctivally (n=6), prednisolone acetate 1% eyedrops Q3H (n=5) or no treatment (n=5). An antigen rechallenge was administered 8 days after initial induction to simulate recurrence of uveitis. The eyes were clinically monitored and graded for ocular inflammation by 2 masked investigators. The combined inflammatory score was compared between the 3 groups.
Results :
Baseline mean inflammatory scores were similar in all 3 groups. Rabbits that received subconjunctival liposomal TA injection had significantly lower mean inflammatory scores than controls at Day 7 (5.63.2 vs 10.63.4, P=0.035), Day 14 (8.43.3 vs 12.51.3, P=0.028) and Day 21 (4.73.0 vs 10.03.9, p=0.03). Mean inflammatory scores was significantly different in rabbits receiving subconjunctival TA compared to those receiving prednisolone acetate 1% eyedrops on Day 7 (5.63.2 vs 91, P=0.05), but not significant on Day 14 (8.43.3 vs 10.21.1, P=0.25) and Day 21 (4.73.0 vs 7.42.1, p=0.12)
Conclusions :
A single dose of subconjunctival liposomal TA is as effective as intensive topical steroid therapy in suppressing inflammation in the rabbit model of uveitis, and provided clinically therapeutic levels that attenuated the inflammatory response even after a rechallenge.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.