AIM: To present the clinical outcomes in efficacy and safety of the Ahmed ClearPath® (ACP) 250 mm2 model as well as our surgical technique. METHODS: Single-center prospective interventional study of uncontrolled glaucoma eyes undergoing ACP implantation, as a standalone procedure or in combination with cataract phacoemulsification. Intraocular pressure (IOP) was evaluated prior to surgery and 1wk, 1, 3, 6mo and 1y postoperatively. In addition, the number of antiglaucoma drugs and intra and postoperative complications were assessed. RESULTS: A total of 30 eyes of 28 patients were included in the study. The patients were on average 72.8 (13.4) years old and 53.6% were male. Totally 40% of the eyes had primary open angle glaucoma, 16.7% had neovascular glaucoma, 16.7% had pseudoexfoliative glaucoma, 10% had glaucoma secondary to pars plana vitrectomy with silicone oil tamponade, 6.7% had aphakic glaucoma, 6.7% had primary congenital glaucoma and 3.3% had pigmentary glaucoma. Before surgery mean IOP was 26.1 (10.8) mm Hg and mean glaucoma medication use was 3.7 (0.5). At 1, 3, 6 and 12mo mean IOP was 16.1, 11.7, 11.8 and 11.5 mm Hg, respectively. Mean glaucoma medication use was 1.9, 1.5, 1.2 and 1.2, respectively. At 1y, complete surgical success was found in 46.7% patients (n=14) and qualified success in 53.3% (n=16). There were no intraoperative complications. Postoperative complications include choroidal effusion (n=5), transient hyphema (n=2), early hypotony with shallow anterior chamber (n=2) and late hemorrhagic choroidal detachment (n=1). CONCLUSION: The ACP appears to be an efficient surgical option for treating refractory glaucoma, achieving good IOP control and decreasing medication burden. The results obtained at 6mo are an important prognostic factor for long-term outcomes.