Clarifying the Optimal Application of SLT Therapy Trial

NCT ID: NCT04967989

Last Updated: 2025-10-02

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

RECRUITING

Clinical Phase

PHASE3

Total Enrollment

790 participants

Study Classification

INTERVENTIONAL

Study Start Date

2021-09-07

Study Completion Date

2027-08-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

The goal of this study is to understand if SLT performed at low energy is as effective as SLT performed at standard energy, and also to see if repeating SLT at low energy once a year will prevent or delay the need for daily eye drop medications better than waiting for SLT to wear off before repeating it.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Glaucoma and Ocular Hypertension

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

The COAST trial underwent a design modification in response to a planned interim analysis. The original and current designs are described here.

Initial Design: Subjects are randomized at study entry to initial SLT at standard or low energy. Subjects who reach Month 12 without discontinuing study treatment are randomized a second time to annual low-energy repeat SLT or as-needed standard energy repeat SLT. There are 2 arms in the first 12 months of the study and 2 arms in Months 13-48.

Current deign: Subjects receive standard at SLT at study entry. Subjects who reach Month 12 without discontinuing study treatment are randomized to annual low-energy repeat SLT or as-needed standard energy repeat SLT. There are 2 arms in the first 12 months of the study and 2 arms in Months 13-48.
Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Trial 1: Initial standard energy SLT

Standard energy SLT is performed as follows: beginning at 0.8 mJ, energy will be titrated up or down within the first 5-10 spots until champagne bubbles are visualized with every 2nd or 3rd spot. Energy can be titrated throughout the procedure, in response to variations in pigmentation, to ensure the appearance of champagne bubbles with every 2nd or 3rd spot throughout the full 360° treatment. Energy should be increased if no bubbles are seen with 5 consecutive spots and decreased if bubbles are seen with 5 consecutive spots.

Group Type ACTIVE_COMPARATOR

Standard Energy SLT

Intervention Type PROCEDURE

SLT performed at standard energy

Trial 2: Month 12 Randomization: Annual Low Energy Repeat SLT

At month 12, eligible subjects will be randomized to undergo repeat SLT either annually at low energy or as needed at standard energy.

Low energy SLT will consist of 100 treatment spots delivered at 0.4 mJ per spot throughout the full 360° treatment, with the exception that energy can be reduced to 0.3 mJ if bubbles are seen with 5 consecutive spots and can be increased back to a maximum of 0.4mJ is no bubbles are seen with 5 consecutive spots.

Group Type EXPERIMENTAL

Low Energy SLT

Intervention Type PROCEDURE

SLT performed at low energy

Trial 2: Month 12 Randomization: As-Needed Repeat SLT at Standard Energy

At month 12, eligible subjects will be randomized to undergo repeat SLT either annually at low energy or as needed at standard energy.

Standard SLT will be performed as follows: beginning at 0.8 mJ, energy will be titrated up or down within the first 5-10 spots until champagne bubbles are visualized with every 2nd or 3rd spot. Energy can be titrated throughout the procedure, in response to variations in pigmentation, to ensure the appearance of champagne bubbles with every 2nd or 3rd spot throughout the full 360° treatment. Energy should be increased if no bubbles are seen with 5 consecutive spots and decreased if bubbles are seen with 5 consecutive spots.

Group Type ACTIVE_COMPARATOR

Standard Energy SLT

Intervention Type PROCEDURE

SLT performed at standard energy

Trial 1: Initial Low Energy SLT

Note: This arm was discontinued following a planned interim analysis.

Low energy SLT will consist of 100 treatment spots delivered at 0.4 mJ per spot throughout the full 360° treatment, with the exception that energy can be reduced to 0.3 mJ if bubbles are seen with 5 consecutive spots and can be increased back to a maximum of 0.4mJ if no bubbles are seen with 5 consecutive spots.

Group Type EXPERIMENTAL

Low Energy SLT

Intervention Type PROCEDURE

SLT performed at low energy

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Low Energy SLT

SLT performed at low energy

Intervention Type PROCEDURE

Standard Energy SLT

SLT performed at standard energy

Intervention Type PROCEDURE

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

1. Age 18 or older and in good health
2. Each eye with one of the following qualifying diagnoses (diagnoses may differ between eyes):

1. High-risk ocular hypertension (OHT): IOP \> 21 mmHg without glaucomatous optic neuropathy (excavation, diffuse or focal thinning or notching of the neuroretinal rim, visible nerve fiber layer defects, or asymmetry of the vertical cup-to-disc ratio of \>0.2 between eyes)
2. Mild primary open-angle glaucoma: glaucomatous optic neuropathy, visual field mean deviation better than -6.0 dB with no points in the central 5° \<15 dB (see figure on next page)
3. Moderate primary open-angle glaucoma: glaucomatous optic neuropathy, visual field mean deviation equal to or worse than -6.0 dB but no worse than -12.0 dB and no central 5° points \<15 dB or mean deviation -12.0 dB or better with 1 central 5° points \<15 dB (see figure on next page).
3. Each eye with BCVA 20/200 (UK 6/60) or better

Exclusion Criteria

1. Use of topical IOP-lowering medications for more than 6 cumulative months at any time in the past 5 years (this is a modification implemented during active enrollment)
2. Any history of IOP-lowering laser (prophylactic iridotomy not included) or surgical procedure
3. Advanced POAG in either eye (worse than moderate POAG as defined above)
4. Glaucoma other than POAG (including pigmentary and pseudoexfoliation glaucoma) in either eye
5. Mean IOP \> 35 mmHg at either the screening or baseline visit in either eye
6. Narrow or closed angle (Shaffer Grade 0, 1, or 2) in either eye
7. Contraindications to SLT or any other study intervention
8. Any corneal pathology that would preclude accurate assessment of IOP by Goldmann tonometry in either eye
9. Any intraocular surgical procedure within the past 6 months in either eye
10. Inability to attend all scheduled study visits
11. Pregnant or planning to become pregnant in the next 4 years
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

National Eye Institute (NEI)

NIH

Sponsor Role collaborator

West Virginia University

OTHER

Sponsor Role collaborator

University of Pittsburgh

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Balasubramani Goundappa

Research Associate Professor

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Tony Realini, MD, MPH

Role: STUDY_CHAIR

West Virginia University

Goundappa K Balasubramani, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Pittsburgh

Stephen Wisniewski, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Pittsburgh

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Harvard Eye Associates

Laguna Hills, California, United States

Site Status RECRUITING

Doheny Eye Center UCLA

Pasadena, California, United States

Site Status RECRUITING

University of California, Davis

Sacramento, California, United States

Site Status RECRUITING

University of California, San Francisco

San Francisco, California, United States

Site Status RECRUITING

Mile High Eye Institute

Sheridan, Colorado, United States

Site Status RECRUITING

Clear Vue Laser Eye Center

Lakeworth, Florida, United States

Site Status RECRUITING

Northwestern Medical Group

Chicago, Illinois, United States

Site Status RECRUITING

Chicago Arbor Eye Institute

Orland Park, Illinois, United States

Site Status RECRUITING

Illinois Eye Center

Peoria, Illinois, United States

Site Status RECRUITING

Wilmer Eye Institute Johns Hopkins

Baltimore, Maryland, United States

Site Status RECRUITING

Massachusetts Eye and Ear

Boston, Massachusetts, United States

Site Status RECRUITING

Ophthalmic Consultants of Boston

Boston, Massachusetts, United States

Site Status RECRUITING

Mark Latina, LLC

Reading, Massachusetts, United States

Site Status RECRUITING

University of Michigan Kellogg Eye Center

Ann Arbor, Michigan, United States

Site Status RECRUITING

Kresge Eye Institute Wayne State University

Detroit, Michigan, United States

Site Status RECRUITING

New York Eye Surgery Associates

The Bronx, New York, United States

Site Status RECRUITING

University Hospitals Eye Institute

Cleveland, Ohio, United States

Site Status RECRUITING

Cleveland Clinic Cole Eye Institute

Cleveland, Ohio, United States

Site Status RECRUITING

Devers Eye Institute

Portland, Oregon, United States

Site Status RECRUITING

Eye Care Specialists

Kingston, Pennsylvania, United States

Site Status RECRUITING

Scheie Eye Institute

Philadelphia, Pennsylvania, United States

Site Status RECRUITING

Wills Eye Hospital

Philadelphia, Pennsylvania, United States

Site Status RECRUITING

UPMC Eye Center

Pittsburgh, Pennsylvania, United States

Site Status ACTIVE_NOT_RECRUITING

Vanderbilt Eye Institute

Nashville, Tennessee, United States

Site Status RECRUITING

Ophthalmology Associates

Fort Worth, Texas, United States

Site Status RECRUITING

Spokane Eye Clinical Research

Spokane, Washington, United States

Site Status RECRUITING

West Virginia University

Morgantown, West Virginia, United States

Site Status RECRUITING

University of Wisconsin-Madison

Madison, Wisconsin, United States

Site Status RECRUITING

Ocular Health Centre

Kitchener, Ontario, Canada

Site Status ACTIVE_NOT_RECRUITING

Countries

Review the countries where the study has at least one active or historical site.

United States Canada

Central Contacts

Reach out to these primary contacts for questions about participation or study logistics.

Tony Realini, MD, MPH

Role: CONTACT

3045986926

Facility Contacts

Find local site contact details for specific facilities participating in the trial.

Jasmin Kaur

Role: primary

949-951-2020

Mayra Raygoza

Role: primary

(626) 817-4747 ext. 19093

Leslie Valverde

Role: primary

916-734-6302

Jenny Lu

Role: primary

(415) 476-5321

Michelle Lopez Galindo

Role: primary

303-241-7310

Michelle Hill

Role: primary

561-432-4141

Angela Giliana

Role: primary

312-695-0252

Lorene Rafol

Role: primary

708-249-1026

Lori Hendershott

Role: primary

309-213-0664

Rucha Thaker

Role: primary

908- 616-1807

Michael Cheung

Role: primary

Tejinder Kaur

Role: primary

Ann Gardikas

Role: primary

781-942-9876

Lindsay Rudberg

Role: primary

734-647-9196

Bayan El-Haik

Role: primary

313-515-5487

Krystina Tavarez-Feliciano

Role: primary

347-860-4474

Sangeetha Raghupathy

Role: primary

216-844-8552

Dusica Vasic

Role: primary

216-445-3840

Jack Rees

Role: primary

503-413-8495

Cheryl Bayley

Role: primary

570-714-5915

Criston Young

Role: primary

856-519-8295

Meskerem Divers

Role: primary

215-825-4712

Marybeth Carter

Role: primary

616-936-1639

Kaitlin Sinclair

Role: primary

940-452-1173

Dylan Waidelich

Role: primary

509-623-9768

Athena Echols, LPN

Role: primary

304-598-6977

Kelly Boyd

Role: primary

608-265-4589

References

Explore related publications, articles, or registry entries linked to this study.

Realini T, Gazzard G, Latina M, Kass M. Low-energy Selective Laser Trabeculoplasty Repeated Annually: Rationale for the COAST Trial. J Glaucoma. 2021 Jul 1;30(7):545-551. doi: 10.1097/IJG.0000000000001788.

Reference Type BACKGROUND
PMID: 33428350 (View on PubMed)

Related Links

Access external resources that provide additional context or updates about the study.

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

UG1EY031651

Identifier Type: NIH

Identifier Source: secondary_id

View Link

UG1EY031654

Identifier Type: NIH

Identifier Source: secondary_id

View Link

STUDY21080018

Identifier Type: OTHER

Identifier Source: secondary_id

STUDY21060171

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

Eye Pressure Lowering Surgery
NCT01931904 RECRUITING
Advanced Glaucoma Progression Study
NCT01742819 ACTIVE_NOT_RECRUITING