Two prospective, controlled, multicenter, double-masked studies--one lasting 6 months (n=594) and the other, 12 months (n=787)--examined the intraocular pressure (IOP)-lowering efficacy of travoprost in 1381 black and nonblack patients with open-angle glaucoma or ocular hypertension. Investigated regimens were travoprost 0.004% once daily, latanoprost 0.005% once daily, and timolol 0:5% twice daily. In both studies, mean IOP was significantly lower in blacks treated with travoprost. The IOP reduction was also significantly greater in blacks after adjustments for age, sex, iris color, diagnosis, and corneal thickness. Timolol lowered mean IOP to a greater extent in nonblack patients. The significantly larger IOP reduction with travoprost compared with timolol in both racial groups was more pronounced in blacks. Travoprost also was superior to latanoprost in blacks. Mean changes from baseline generally were greater for black than for nonblack patients, although the differences did not achieve statistical significance. The response rate to travoprost was higher in blacks. The most common adverse effect was hyperemia.