Two Trabecular Micro-bypass Stents & Postoperative Travoprost to Treat Glaucoma Subjects on Two Hypotensive Agents

The study design is as follows: * Prospective, single-arm study. * Subjects with open-angle glaucoma and medicated IOP \> 18 mmHg and ≤ 30 mmHg. * Subjects on two topical ocular hypotensive medications (one a prostaglandin). * Implantation of two iStent inject devices (if IOP is \< 6 mmHg, at any point during the postoperative follow-up, medication will not be prescribed or will be discontinued). * IOP will be measured by two (2) observers to minimize bias; observer 1 will look through the slit lamp and turn the dial with readings being masked, and observer 2 will document the IOP. * Follow-up through 60 months postoperative (or up to 61 months if subject needs to undergo terminal washout). * Descriptive statistics will be tabulated. * Medical therapy considered necessary for the subject's welfare can be implemented at any time during the study at the investigator's discretion.