Glaukos Corporation has completed patient enrollment in its U.S. pivotal clinical study supporting the potential 510(k) clearance of the PRESERFLO MicroShunt for adult patients with primary open-angle glaucoma (POAG).
Hold up—doesn’t Santen own this device?
Yes and no. The FDA accepted Santen’s premarket approval (PMA) application for the device (then-referred to as DE-120) in 2020.
However: Fast forward to 2021, Santen entered into an agreement with Glaukos for the latter to acquire the exclusive rights to develop and commercialize the PRESERFLO MicroShunt within the United States.
Notably: Those rights also extended to markets in Australia, Brazil, Canada, Mexico, and New Zealand.
Also worth mentioning: The device was granted approval in Canada and Australia in mid-2021 before making its debut in those commercial markets in 2022.
Noted. Now for a rundown on it.
The PRESREFLO MicroShunt is a flexible, ab-externo glaucoma drainage device for lowering intraocular pressure (IOP) via implantation under the subconjunctival (SC) space.
Its construction: The device is "precisely engineered” from a proprietary, biocompatible material known as SIBS (poly[styrene-block-isobutylene-block-styrene]).
- To note: SIBS is a biostable thermoplastic elastomer with physical properties overlapping with silicon rubber and polyurethane.
- Importantly: This material is clinically proven to minimize inflammation, scarring, and encapsulation. Check out the science behind it.
Talk more about its features.
Measuring 8.5 mm in length, the device includes a tube of 350 μm outer diameter and a lumen of 70 μm for optimizing aqueous flow and decreasing hypotony risk.
Among its features:
- Beveled tip to enable debris clearance and prevent blockage
- 1 mm planar fins to prevent migration and periannular leakage
- 3 mm distal tail to allow for posterior bleb formation
Can you explain how the device treats high IOP?
A visual of this minimally-invasive procedure can be seen here.
As for the procedure itself: Check out those details.
Anything we should know about the target patient base?
Those would be OAG patients with one key criteria: Those in which “IOP remains uncontrollable while on maximum tolerated medical therapy and/or where glaucoma progression warrants surgery.”
- See here for contraindications.
Next up: this pivotal trial.
The PRESERFLO MicroShunt study is a prospective, multicenter, single-arm clinical trial that has officially enrolled its target of a minimum of 110 participants across North America.
These participants include OAG patients who previously (and unsuccessfully) underwent incisional or cilioablative glaucoma surgery and whose IOP was still “inadequately controlled” by IOP-lowering medications.
What’s being evaluated?
The primary effectiveness endpoint is a ≥ 20% reduction in mean diurnal IOP from baseline at 12 months postoperatively.
- This must be achieved without an increase in the number of IOP-lowering medication classes from baseline.
… and the plan?
Glaukos is intending to use the pivotal study results to support a future submission to the FDA for commercial clearance of the PRESERFLO MicroShunt.
So when can we expect a data readout?
That’s currently to be determined … but we’ll keep you posted!
And in the meantime, is there any prior data on this device?
Considering its regulatory status in Canada and Australia—you bet.
As spotlighted on the PRESERFLO MicroShunt website, clinical outcomes associated with its implantation (from baseline to month 12) compared to trabeculectomy include:
- 14.3 mmHg mean postop IOP on 0.6 mean medications at month 12
- 74% lower rate of hypotony requiring intervention vs trabeculectomy through month 12
- See the next section for adverse events (AEs)
- 72% of treated patients medication-free at month 12
- 39% lower rate of interventions vs trabeculectomy through month 12
- 29% mean IOP reduction from medicated baseline
To note: These outcomes were based on a 12-month evaluation of over 500 OAG patients.
Any glaucoma-related AEs worth mentioning?
A few … Glaukos also noted that the device exhibited “lower rates” of these AEs in comparison to those associated with trabeculectomy at month 12. See for yourself:
- Hypotony (IOP < 6 mmHg at any time)
- PRESERFLO: 28.9%; trabeculectomy: 49.6%
- Persistent hypotony
- PRESERFLO: 7.1%; trabeculectomy: 21.2%
- Hypotony requiring intervention
- PRESERFLO: 2.0%; trabeculectomy: 7.6%
- Total bleb leaks
- PRESERFLO: 8.9%; trabeculectomy: 14.5%
- Late bleb leaks (after month 1 follow-up visits)
- PRESERFLO: 3.0%; trabeculectomy: 6.9%