Comparing pegaptanib and triamcinolone efficacy in the rat choroidal neovascularization model.

OBJECTIVE

To evaluate the prophylactic effect of intravitreal pegaptanib sodium on choroidal neovascularization membrane (CNVM) development and compare its performance with that of triamcinolone acetonide.

METHODS

In drug-treated and control groups, CNVMs were induced by laser trauma. Immediately after undergoing the laser procedure, animals received intravitreal injections of pegaptanib sodium, 8 or 17 mug; triamcinolone acetonide, 200 mug; or a vehicle solution. After 21 days, fluorescein angiography was performed. The CNVM mean diameters and radial thicknesses were measured histologically.

RESULTS

Mean CNVM diameters were 10% to 13% smaller in pegaptanib-treated eyes and 43% smaller in triamcinolone-treated eyes compared with laser-only control eyes. Late-stage fluorescein angiography leakage scores, on a scale of 0 to 3, suggested a statistical difference between triamcinolone- (0.6) and pegaptanib(8 microg)-treated (1.5) groups compared with the laser-only control group (2.0). The CNVM mean thicknesses were greater in the pegaptanib(8 microg)- (79 microm) and pegaptanib(17 microg)-treated (71 microm) groups and significantly smaller in the triamcinolone-treated group (26 microm) compared with the laser-only control group (67 microm).

CONCLUSION

In this animal model of choroidal neovascularization, intravitreal pegaptanib exhibited marginal or no effect on CNVM development; whereas intravitreal triamcinolone evoked robust inhibition of CNVMs. Clinical Relevance Pegaptanib treatment may be insufficient to prevent CNVM formation.