Clinical trial NCT02873806: Two Trabecular Micro-bypass Stents & Postoperative Travoprost to Treat Glaucoma Subjects on Two Hypotensive Agents
Official title: A Prospective Evaluation of Open-angle Glaucoma Subjects on Two Topical Hypotensive Medications (One a Prostaglandin) Treated With Two Trabecular Micro-bypass Stents (iStent Inject) and a Postoperative Topical Prostaglandin
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Open-angle Glaucoma
Lead sponsor: Glaukos Corporation
Sponsor class: INDUSTRY
First posted: 2016-08-22
Enrollment: 53
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The study objective was to evaluate the intraocular pressure (IOP) lowering effect of two iStent devices in eyes of subjects with primary open-angle glaucoma, washed out of two anti-glaucoma medications (one a Prostaglandin) prior to stent implantation.

Detailed description: 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.

Eligibility criteria: Inclusion Criteria:

Screening Exam Inclusion Criteria:

* Phakic patients or pseudophakic patients with posterior chamber intraocular lenses (PC-IOLs)
* Primary open-angle glaucoma (including pigmentary or pseudoexfoliative)
* C/D ratio ≤ 0.9
* Visual field defects, or nerve abnormality characteristic of glaucoma
* Two topical hypotensive medications at time of screening exam
* IOP \> 18 mmHg and ≤ 30 mmHg (medicated) at screening exam
* Study eye BCVA 20/100 or better
* Normal angle anatomy as determined by gonioscopy
* Absence of peripheral anterior synechia (PAS), rubeosis or other angle abnormalities that could impair proper placement of stent

Baseline Exam Inclusion Criteria:

* Subject has completed appropriate medication washout
* Mean IOP \> 22 mmHg and ≤ 38 mmHg after anti-glaucoma medication washout period
* A 3mmHg IOP increase over screening mean IOP

Exclusion Criteria:

Screening Exam Exclusion Criteria:

* Aphakic patients or pseudophakic patients with anterior chamber IOLs (AC-IOLs)
* Prior stent implantations (study eye)
* Traumatic, uveitic, neovascular, or angle-closure glaucoma; or glaucoma associated with vascular disorders
* Functionally significant visual field loss, including severe nerve fiber bundle defects
* Prior incisional glaucoma surgery
* Prior SLT within 90 days prior to screening
* Prior ALT
* Iridectomy or laser iridotomy
* Ineligibility for ocular hypotensive medication washout period as determined by the investigator.
* Any active corneal inflammation or edema (e.g., keratitis, keratoconjunctivitis, keratouveitis)
* Clinically significant corneal dystrophy (e.g., bullous keratopathy, Fuch's dystrophy); any guttata
* Corneal surgery (prior or anticipated) of any type (including LASIK, LASEK, PRK, etc.) that may interfere with IOP measurement reliability
* Corneal opacities that would inhibit visualization of the nasal angle
* Congenital or traumatic cataract
* Retinal or optic nerve disorders that are not associated with the existing glaucoma condition
* Elevated episcleral venous pressure such as associated with: active thyroid orbitopathy; cavernous sinus fistula; Sturge-Weber syndrome; orbital tumors; orbital congestive disease
* Clinically significant sequelae from trauma
* Chronic ocular inflammatory disease or presence of active ocular inflammation

Baseline Exam Exclusion Criteria:

* Subject did not complete medication washout
* Mean IOP \< 22 mmHg or \> 38 mmHg after anti-glaucoma medication washout
* Subject does not have a 3mmHg IOP increase over screening mean diurnal

Primary outcomes:
measure: Mean intraocular pressure reduction of 20% or more versus baseline with reduction of 1 medication
timeFrame: 12 months postoperative
Secondary outcomes:
measure: Mean intraocular pressure of 18 mmHg or less versus baseline with reduction of 1 medication
timeFrame: 12 months postoperative
Other outcomes:
Locations:
city: Yerevan
country: Armenia
facility: S.V. Malayan's Ophtalmology Centre
Study officials:
affiliation: S.V. Malayan Eye Center
name: Lilit Voskanyan, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Berdahl J, Voskanyan L, Myers JS, Hornbeak DM, Giamporcaro JE, Katz LJ, Samuelson TW. Implantation of two second-generation trabecular micro-bypass stents and topical travoprost in open-angle glaucoma not controlled on two preoperative medications: 18-month follow-up. Clin Exp Ophthalmol. 2017 Nov;45(8):797-802. doi: 10.1111/ceo.12958. Epub 2017 Jun 2.