24-month safety and efficacy outcomes remain favourable for second-generation stents

Results from a prospective, open-label trial show that implantation of two second generation trabecular micro-bypass stents (GTS400; iStent inject, Glaukos) in eyes with mild to moderate open angle glaucoma is safe and provides sustained IOP lowering through two years. 

The study enrolled 55 phakic eyes. Mean preoperative C/D ratio was 0.7±0.1, mean IOP on one medication was 20.9±1.0 mmHg, and mean IOP 1 month post-washout was 25.0±1.5 mmHg. 

At 12 months, 98 per cent of eyes met the primary and secondary efficacy endpoints (IOP reduction ≥20% vs. post-washout IOP and ≤18 mm Hg) as well as the higher efficacy threshold of IOP reduction ≥30%. One eye with an IOP of 23 mm Hg underwent trabeculectomy.

Among the 54 eyes seen at 24 months, mean IOP was 14.6±1.1 mmHg; 97% met the primary, secondary, and IOP reduction ≥30% efficacy endpoints. Two eyes were on a single IOP-lowering medication, and 17 of 19 eyes with pre-existing cataract had undergone cataract surgery. 

“The surgery for the second generation trabecular micro-bypass stents is fast, easy to performafter a short learning curve, and causes very little trauma,” said Dr. Tetz, Berlin, Germany. “We can carefully state based on these data from follow-up to 2 years that iStent Inject implantation as a sole initial surgical procedure is feasible, safe, and capable of providing significant reductions in IOP and medication use for patients with mild to moderate open angle glaucoma.”