Posters

Pivotal study of second-generation trabecular micro-bypass stents (iStent inject®) implanted in conjunction with cataract surgery: analysis by baseline IOP

Poster Details

First Author: S.Sarkisian USA

Co Author(s):                        

Abstract Details

Purpose:

This US IDE pivotal trial evaluates the IOP-lowering efficacy and safety of the second-generation trabecular micro-bypass stents (iStent inject®) implanted in conjunction with cataract surgery compared to cataract surgery alone in subjects with mild to moderate open-angle glaucoma. This reports additional analysis by baseline IOP.

Setting:

40 US sites enrolled and randomized subjects for this study.

Methods:

This was a 2-year prospective, randomized, concurrently controlled, parallel groups, US IDE multicenter trial. The study enrolled subjects ≥45 years diagnosed with mild to moderate OAG on 1 to 3 medications with a cataract eligible for surgery. Baseline post-washout mean diurnal IOP of 21-36 mmHg was required in the study eye. Qualified subjects were randomized to implantation with 2 iStent inject stents in conjunction with cataract surgery or cataract surgery alone. Annual medication washouts were performed to assess unmedicated IOP. Key study assessments included: IOP, BCVA, pachymetry, VF, specular microscopy, biomicroscopy, gonioscopy, funduscopy (including ON and C/D ratio), and AEs.

Results:

505 subjects were randomized. Both primary and secondary effectiveness endpoints were met (proportion of subjects with ≥20% reduction in IOP and IOP reduction from baseline at Month 24, respectively).  A high safety profile was observed. Analyses of the secondary endpoint by baseline IOP indicated a significant difference between groups in favor of iStent inject+phaco at all baseline IOP groups. Notably, greater IOP reductions were seen in the higher baseline IOP groups. In eyes with baseline IOP ≥30 mmHg, 9.8 mmHg unmedicated DIOP reduction was achieved in the iStent inject+phaco group vs 5.5 mmHg reduction in the phaco group (p<0.05).

Conclusions:

Clinically and statistically significant IOP reduction out to 2 years was demonstrated in this pivotal study and has been previously reported. iStent inject effectively reduces IOP across different ranges of baseline IOP. Consistent with the current literature, a greater reduction is seen in eyes with higher baseline IOP.  Although iStent inject is often used in mild-to-moderate glaucoma, there is evidence suggesting its performance in more moderate glaucoma cases.

Financial Disclosure:

... is employed by a for-profit company with an interest in the subject of the presentation