Baseline mean medicated intraocular pressure (IOP)
Month-24 mean IOP (primary outcome)
Month-24 mean IOP
The change in mean IOP from medicated baseline was -6.5 ± 5.3 at month 12 (primary outcome) and -6.2 ± 4.0 at month 24 (P < .001) in the mITT population (N = 202).
*Prospective, nonrandomized, open-label, multicenter, 2-year European study evaluated the effectiveness of the XEN® Gel Stent as primary surgical intervention in reducing IOP and IOP-lowering medication count in 200 patients (219 eyes) with medically uncontrolled, moderate primary open-angle glaucoma. Eyes with medicated baseline IOP 18 to 33 mm Hg on 1 to 4 topical IOP-lowering medications were implanted with XEN® alone or phaco + XEN®. The modified intent-to-treat population included all enrolled eyes with verified informed consent documentation that received a XEN® implant and met the IOP and IOP-lowering medication count inclusion criteria.
This study was funded by Allergan® plc (Dublin, Ireland; formerly AqueSys, Inc.). Herbert Reitsamer has received consulting honoraria from Allergan®. Chelvin Sng has received consulting honoraria from Allergan®, Glaukos (San Clemente, California), Alcon (Fort Worth, Texas), and Santen Pharmaceuticals (Osaka, Japan). Vanessa Vera has received consulting honoraria from Allergan®. Keith Barton has received consulting honoraria from Alcon, Allergan® and Glaukos. Ingeborg Stalmans has received consulting honoraria from Allergan®. Markus Lenzhofer declares that he has no conflict of interest.
APEX study limitations8
- Variability in perioperative regimens may have impacted study outcomes. At the time of initiation of this study, XEN® was new on the market and no best practices were established, so the study results also reflect the investigators’ learning curve with the surgery and the variation in preoperative and postoperative regimens associated with typical clinical settings
- The study population underrepresented patients who were not White; < 5% were Asian or Black/African ethnicities. Black/African and Asian ethnicities have been reported to have increased risk for trabeculectomy failure
- The APEX study design was nonrandomized and open label, which does not permit direct comparison to other MIGS and surgical techniques
mITT = modified intent-to-treat; phaco = phacoemulsification with intraocular lens replacement.
DECREASES IN MEAN IOP FROM MEDICATED BASELINE WERE SIMILAR WITH OR WITHOUT CATARACT SURGERY8
Similar results were observed in both treatment groups at all postoperative visits up to 24 months (P > .4, between-group comparisons).
POST HOC ANALYSIS: 2-YEAR RESULTS ACROSS A RANGE OF BASELINE PRESSURES9
REDUCTION IN MEAN NUMBER OF IOP-LOWERING MEDICATIONS VS BASELINE (mITT POPULATION)8,†
51.1% (91/178) and 44.7% (72/161) of eyes were topical medication–free at months 12 and 24, respectively.
APEX 2-YEAR STUDY SAFETY DATA8
Intraoperative Complications (10/218)
4.6% Anterior chamber bleeding in 2.8% (6/218) of eyes was the most common.
Persistent Hypotony (0/218)
0% Defined as IOP < 6 mm Hg at 2 consecutive postoperative visits > 30 days apart.
Postoperative Ocular Adverse Events (65/218)
29.8% Glaucoma-related SSI due to uncontrolled IOP (14/218; 6.4%) and hyphema (10/218; 4.6%) were most frequently reported.
Numeric Hypotony (44/218)
20.2% Defined as IOP < 6 mm Hg (self-resolved) within the first 2 postoperative weeks.
2.3% (5/218) were recorded as adverse events, all of which occurred within 1 week post implantation and self-resolved within 1 month
Ocular Serious Adverse Events (6/218) (5 in study eyes, 1 in untreated fellow eye)
2.8% Cataract aggravated, retinal disorder (central retinal vein occlusion reported at 12 months, without elevated IOP), conjunctival erosion (implant exposure), glaucoma-related SSI (due to hospitalization for surgery), endophthalmitis (reported 15 months after implantation), and high IOP with SSI (cyclodestructive procedure) in the untreated fellow eye (n = 1 each).
APEX Study Criteria8
Two-year, prospective, nonrandomized, open-label, multicenter study
- 200 adult patients (219 eyes) with moderate primary open-angle glaucoma uncontrolled on topical therapy
- Mean age: 71.8 (± 10.5) years
- Prior cataract surgery: 25 (13.5%)
- Mean visual field mean deviation (MD) score: -8.0 (± 8.9) dB
- Mean medicated IOP at baseline: 21.4 (± 3.6) mm Hg
- Mean IOP-lowering medications at baseline: 2.7 (± 0.9)
PRIMARY EFFECTIVENESS MEASURES6
- Changes in mean IOP and mean number of topical IOP-lowering medications in the study eyes from baseline to month 12
- These parameters were also assessed at all other postoperative visits up to 24 months (secondary effectiveness measures)
PRIMARY SAFETY MEASURES6
- Intraoperative complications
- Monocular best-corrected visual acuity
- Biomicroscopic slit lamp and ophthalmoscopy findings
- Postoperative adverse events (each postoperative visit through month 24)