Tube Shunt Implantation for Glaucoma

(B350vsCP250 Trial)

Overseen By Sharon Michalovic, BA

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: State University of New York at Buffalo

Disqualifiers: Phakic, Aphakic, Under 18, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores two different tube shunts, the Baerveldt 350 and Ahmed ClearPath 250, to assess their effectiveness in lowering eye pressure in individuals with severe glaucoma not controlled by other treatments. Glaucoma can cause vision loss due to increased pressure inside the eye. Participants will receive one of the two shunts to help manage their condition. The trial seeks individuals whose previous glaucoma treatments have failed and who have undergone cataract surgery (pseudophakia). As an unphased trial, it offers a unique opportunity for patients to explore new treatment options for managing glaucoma.

Do I have to stop taking my current medications for the trial?

The trial protocol does not specify whether you need to stop taking your current medications. Please consult with the trial coordinators for more details.

What prior data suggests that these tube shunts are safe for glaucoma patients?

Research has shown that both the Ahmed ClearPath 250 and Baerveldt 350 tube shunts have been studied for their safety in treating glaucoma. Studies indicate that the Ahmed ClearPath 250 is generally well-tolerated. Over a 24-month period, most patients did not experience serious side effects, and the device proved safe when used alone or with other glaucoma treatments.

Similarly, the Baerveldt 350 has been tested in many patients with uncontrolled glaucoma. Research suggests it is also safe, with no major safety concerns reported. Patients using the Baerveldt 350 generally tolerated it well, with few negative effects noted.

Overall, both devices have demonstrated a good safety record in previous studies. Patients considering joining a trial can feel confident about the safety of these treatments based on existing evidence. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Unlike the standard of care for glaucoma, which often includes medications or laser treatments, the Ahmed ClearPath 250 and Baerveldt 350 focus on surgical intervention to manage severe cases. These treatments are unique because they involve implanting a tube shunt, which helps to effectively drain excess fluid from the eye, reducing intraocular pressure. Researchers are excited about these treatments because they offer a more long-term solution for patients with uncontrolled glaucoma, potentially reducing the need for ongoing medication. Additionally, the specific design of the Ahmed ClearPath 250 and Baerveldt 350 shunts may offer improved safety and efficacy compared to existing surgical options.

What evidence suggests that this trial's tube shunts could be effective for glaucoma?

In this trial, participants will receive either the Baerveldt 350 or the Ahmed ClearPath 250 tube shunt implantation to treat severe, uncontrolled glaucoma. Studies have shown that both devices effectively lower eye pressure in such patients. The Baerveldt 350 has successfully reduced eye pressure in cases where other surgeries, like trabeculectomy, have failed or were likely to fail. Research indicates that the Ahmed ClearPath 250 is safe and effective, either alone or with other procedures, providing significant eye pressure reduction for those with uncontrolled glaucoma. Numerous studies support both treatments, demonstrating their ability to manage glaucoma when other medical treatments are insufficient. ^{1 2 3 4 5}

Who Is on the Research Team?

Asher Weiner, MD

Principal Investigator

The Ross Eye Institute

Are You a Good Fit for This Trial?

This trial is for adults over 18 with advanced glaucoma not controlled by medication, laser, or previous surgery. They must understand and agree to the study's process. It excludes women who can have children, pregnant women, those under 18, and patients without a lens implant after cataract removal.

Inclusion Criteria

You have had cataract surgery and now have an artificial lens in your eye.

I have severe glaucoma not managed by current treatments, needing a tube shunt.

I am willing and able to sign the study consent form.

Exclusion Criteria

I am able to understand and sign the study consent form.

I am a woman who could potentially become pregnant.

I am currently pregnant.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Surgery

Participants undergo tube shunt implantation surgery with either Baerveldt 350 or Ahmed ClearPath 250

1 day

1 visit (in-person)

Postoperative Follow-up

Participants are monitored for changes in intraocular pressure and other safety and efficacy measures

2 years

Regular visits (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• Ahmed ClearPath 250
• Baerveldt 350

Trial Overview

The trial compares two devices designed to lower eye pressure in glaucoma: Baerveldt 350 and Ahmed ClearPath 250 tube shunts. The goal is to see which one is safer and more effective at preserving vision in patients with severe glaucoma.

How Is the Trial Designed?

Group I: Baerveldt 350 Active Control 1 Intervention

The patients in this arm will receive a Baerveldt 350 tube shunt implantation for the treatment of their severe uncontrolled glaucoma.

Group II: Ahmed ClearPath 250 Active Control 1 Intervention

The patients in this arm will receive an Ahmed ClearPath 250 tube shunt implantation for the treatment of their severe uncontrolled glaucoma.

Ahmed ClearPath 250 is already approved in United States for the following indications:

Approved in United States as Ahmed ClearPath Glaucoma Drainage Device for:

• Refractory glaucoma where previous surgical treatment has failed or is not expected to provide satisfactory results, including neovascular glaucoma, congenital or infantile glaucoma, and refractory glaucoma resulting from aphakia or uveitis.

Who Is Running the Clinical Trial?

State University of New York at Buffalo

Lead Sponsor

Trials

279

Recruited

52,600+

Published Research Related to This Trial

A comprehensive analysis of 79 studies comparing new-generation transcatheter aortic valve implantation (TAVI) devices found that the Direct Flow Medical (DFM) valve had the lowest rates of device success and complications, while the Sapien 3 valve showed the best outcomes for reducing mortality and stroke rates.

The study suggests that while DFM stands out for certain metrics, other devices like Lotus and Evolut excel in specific areas such as reducing paravalvular leaks and major bleeding, indicating that different TAVI devices may be optimized for various patient needs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparisons of different new-generation transcatheter aortic valve implantation devices for patients with severe aortic stenosis: a systematic review and network meta-analysis. Yang, YX., Liu, XM., Fu, Y., et al.[2023]

The EinsteinVision 2.0 3D high-definition endoscopic system was successfully used for minimally invasive tricuspid valve repair in an 81-year-old patient, demonstrating its effectiveness in complex heart surgeries.

This technique allowed for precise manipulation through a small incision, avoiding the need for rib spreading, which can reduce recovery time and improve patient safety.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Minimally Invasive Cardiac Surgery Using a 3D High-Definition Endoscopic System. Ruttkay, T., Götte, J., Walle, U., et al.[2017]

The Edwards INTUITY Valve System demonstrated excellent safety and efficacy in a study of 500 patients with severe aortic stenosis, showing a low 30-day mortality rate of 0.8% and high overall survival rates of 94%, 89%, and 81% at 1, 3, and 5 years, respectively.

The valve exhibited good hemodynamic performance with mean gradients remaining stable over 5 years, although there was a notable 8.6% rate of new pacemaker implantation, indicating a need for careful monitoring post-surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intermediate-term outcome of 500 consecutive rapid-deployment surgical aortic valve procedures†. Andreas, M., Coti, I., Rosenhek, R., et al.[2020]

In a study of 17 patients with traumatic glaucoma, implantation of either Ahmed or Baerveldt tube shunts resulted in an 83% surgical success rate at 1 year, significantly lowering intraocular pressure (IOP) from an average of 34.1 mm Hg to 16.1 mm Hg.

The procedure also reduced the need for ocular hypotensive medications from an average of 3.1 to 1.3, demonstrating both efficacy in IOP control and a positive impact on medication burden for patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Surgical Outcomes of Ahmed or Baerveldt Tube Shunt Implantation for medically Uncontrolled Traumatic Glaucoma. Yadgarov, A., Liu, D., Crane, ES., et al.[2022]

In a study of 118 patients comparing Baerveldt and Ahmed shunt implants for refractory glaucoma, the Ahmed group showed better early control of intraocular pressure (IOP) and required fewer glaucoma medications shortly after surgery.

However, the Ahmed shunt was associated with a higher rate and earlier onset of clinical bleb encapsulation compared to the Baerveldt shunt, indicating a potential trade-off in outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Ahmed shunt versus the Baerveldt shunt for refractory glaucoma: a single-surgeon comparison of outcome. Tsai, JC., Johnson, CC., Dietrich, MS.[2023]

Both Ahmed and Baerveldt shunt implants show similar long-term success rates in controlling intraocular pressure (IOP) for up to 48 months, with 4-year success rates of 62% for Ahmed and 64% for Baerveldt.

Patients with Ahmed implants required more glaucoma medications starting at 18 months post-surgery, while Baerveldt patients experienced earlier failure, indicating different long-term management needs for each implant type.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Ahmed shunt versus the Baerveldt shunt for refractory glaucoma II: longer-term outcomes from a single surgeon. Tsai, JC., Johnson, CC., Kammer, JA., et al.[2022]

Glaucoma drainage devices (GDD) can effectively lower intraocular pressure in patients with refractory glaucoma, but they face challenges such as bleb fibrosis, which is a major cause of long-term failure and can lead to serious complications like endophthalmitis and hypotony.

Recent advancements, including the use of anterior segment OCT for better visualization and the exploration of novel materials and nanotechnology, may improve the effectiveness and safety of GDD in managing glaucoma.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Development of glaucoma drainage device]. Zou, X., Duan, XC.[2009]

The Ahmed ClearPath (ACP) glaucoma drainage device demonstrated significant intraocular pressure (IOP) reduction in patients with refractory glaucoma, achieving a mean IOP of 13.7 mm Hg after 6 months, which is a 43% decrease from baseline.

The ACP device was found to be safe, with common adverse events including anterior chamber inflammation (16.3%) and hyphema (15.4%), but overall it showed comparable efficacy to other glaucoma drainage devices, making it a viable option for patients with uncontrolled glaucoma.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical Outcomes of Ahmed ClearPath Implantation in Glaucomatous Eyes: A Novel Valveless Glaucoma Drainage Device. Grover, DS., Kahook, MY., Seibold, LK., et al.[2023]

In a study of 104 eyes from 94 patients, the Ahmed glaucoma valve (AGV) showed a significantly higher rate of tube malpositioning (46%) compared to the Baerveldt drainage implant (BDI) (8%), indicating that the AGV's weaker rigidity may contribute to this issue.

Both AGV and BDI effectively reduced intraocular pressure from an average of 27.9 mm Hg before surgery to 12.9 mm Hg after surgery, demonstrating the efficacy of ciliary sulcus tube insertion for glaucoma management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Operative Complications of Glaucoma Drainage Implant Tube Insertion Through the Sulcus for Pseudophakic Eye. Asaoka, S., Kasuga, T., Matsunaga, T., et al.[2021]

The Baerveldt glaucoma drainage device significantly reduced intraocular pressure (IOP) more than the Ahmed device in patients with uveitic glaucoma, achieving a 60.3% reduction compared to 44.5% for Ahmed.

While Baerveldt had a higher complete success rate (30% vs. 9%) and required fewer medications, it also had a higher complication rate (51.4% vs. 20.9%), with hypotony being a common cause of failure in the Baerveldt group.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ahmed Versus Baerveldt Glaucoma Drainage Device in Uveitic Glaucoma: A Retrospective Comparative Study. Sinha, S., Ganjei, AY., McWatters, Z., et al.[2021]

In a study of 64 patients with refractory glaucoma, the Baerveldt-350 implant and Ahmed valve showed similar effectiveness in controlling intraocular pressure (IOP) after one year, with IOP measurements of 12.1 mm Hg and 13.6 mm Hg respectively.

Both devices had comparable surgical success rates (65.6%) and complication rates, indicating that either option can be a viable treatment for patients who do not respond to other glaucoma treatments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Baerveldt-350 implant versus Ahmed valve for refractory glaucoma: a case-controlled comparison. Syed, HM., Law, SK., Nam, SH., et al.[2023]

In a study involving 11 eyes with uncontrolled intraocular pressure (IOP), the pars plana Ahmed glaucoma valve combined with triamcinolone-assisted vitrectomy significantly reduced the mean IOP from 33.64 mmHg preoperatively to 17.09 mmHg at 6 months and 17.45 mmHg at 12 months post-surgery.

The number of antiglaucoma medications required by patients also decreased dramatically, from an average of 3.27 medications before surgery to just 0.64 at 6 months and 0.55 at 12 months, indicating improved management of glaucoma.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pars plana Ahmed glaucoma valve implantation with triamcinolone-assisted vitrectomy in refractory glaucomas. Dada, T., Bhartiya, S., Vanathi, M., et al.[2022]

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