Glaucoma filtration surgery in nonhuman primates using taxol and etoposide in polyanhydride carriers

To determine the effect of taxol and etoposide, hydrophobic drugs with antifibrosis activity, on the outcome of filtration surgery in glaucomatous monkeys.

Elevated intraocular pressure was produced bilaterally in eight cynomolgus monkeys by laser treatment of the trabecular meshwork. Four animals subconjunctivally received a polyanhydride disk containing 1 mg etoposide at the time of posterior lip sclerectomy in one eye; the other eye received an identical disk without drug. Similarly, four animals received a disk containing 50 micrograms of taxol in one eye and a blank disk in the other.

Eyes treated with taxol had lower intraocular pressures than control eyes from 20 days after surgery until death. Eyes with satisfactory filtration bleb appearance and patent fistulae on histologic examination had lower intraocular pressures. The intraocular pressure was lower and the duration of success longer in the etoposide-treated eyes (mean, 16 days) compared to that of the fellow eyes (mean, 10 days), but the difference was not statistically significant.

Use of polyanhydride disks containing taxol, but not etoposide, had a marked beneficial effect on intraocular pressure and bleb appearance after experimental filtration surgery in monkeys. The difference between the two agents may result from the greater antiproliferative potency of taxol and its greater duration of release from the polymer.