Single Session vs Multiple-Session Panretinal Photocoagulation for Treatment of Proliferative Diabetic Retinopathy (SMART-PRP)

November 17, 2025 updated by: Vastra Gotaland Region

Single Session vs Multiple-Session Panretinal Photocoagulation With Navigated Laser in Proliferative Diabetic Retinopathy - The SMART-PRP Study

Proliferative diabetic retinopathy (PDR) is the leading cause for blindness in working-age adults. The current gold standard treatment for PDR is panretinal photocoagulation (PRP). In current clinical practice, both single-session and multiple-session PRP approaches are widely accepted and utilized. The purpose of this study is to compare the safety and effectiveness of single-session and multiple-session PRP.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Proliferative diabetic retinopathy (PDR) is a well-known complication for both type 1 and type 2 diabetes mellitus (DM) and it is the leading cause for blindness in working-age adults. The current gold standard treatment for PDR, established more than four decades ago by the Diabetic Retinopathy Study (DRS), is panretinal photocoagulation (PRP). The treatment goal is to halt the progression of PDR by destroying parts of the peripheral retina in a pattern fashion and hence preserving the visually important central macular region. The tissue destruction reduces the area of ischemia and reduces the production of vascular endothelial growth factor (VEGF), which drives the formation of neovascular proliferations. In the management of PDR, panretinal photocoagulation (PRP) stands as a cornerstone treatment. In current clinical practice, both single-session and multiple-session PRP approaches are widely accepted and utilized. The choice between these approaches often depends on the practitioner's preference, patient characteristics, and specific clinical circumstances.

Although both single-session and multiple-session PRP are employed in practice, there's an ongoing debate regarding their comparative safety and effectiveness. Older studies suggest a heightened risk of diabetic macular edema (DME) with single-session PRP, while newer research, particularly those involving milder laser techniques, indicates that the risk might be similar regardless of the number of sessions. This inconsistency in findings underscores the need for further research and the investigators aim to shed light over this with this prospective, controlled and randomized interventional study.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
40

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Age > 18 years.
  • Patients with type 1 or type 2 Diabetes Mellitus with newly diagnosed Proliferative Diabetic Retinopathy, PDR.
  • Visual acuity ≥ 0.1 Snellen.
  • CRT of less than 300 micrometer measured by OCT without cysts in the neuroretina.
  • Clear media and adequately dilated pupil for PRP.

Exclusion Criteria:

  • Intraocular surgery within the last 4 months or planned within the next 3 months.
  • Previous or current center-involved diabetic macular edema (Ci-DME).
  • Previous PRP, intravitreal treatment (IVT), or macular laser treatment in study eye.
  • Treatment with medications known to risk macular edema.
  • Media opacity preventing adequate PRP.
  • General medical condition making office laser treatment very difficult or impossible.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Active Comparator: Single-session panretinal PRP (SS-PRP)
Administration of all panretinal photocoagulation (PRP) treatment in one comprehensive session, typically delivered in a single clinical visit.
Procedure: Single-session panretinal PRP (SS-PRP)
Administration of panretinal photocoagulation (PRP) treatment with navigated laser using Navilas in one comprehensive session, typically delivered in a single clinical visit.
Active Comparator: Multiple-session panretinal PRP (MS-PRP)
Administration of panretinal photocoagulation (PRP) treatment over two separate visits with at least one week apart.
Procedure: Multiple-session panretinal PRP (MS-PRP)
Administration of panretinal photocoagulation (PRP) treatment with navigated laser using Navilas over two separate visits with at least one week apart.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Central subfield retinal thickness (CRT)
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in CRT
Baseline and 1, 3 and 6 months after treatment
Vessel Perfusion Density (VPD)
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in VPD
Baseline and 1, 3 and 6 months after treatment
Vessel Length Density (VLD)
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in VLD
Baseline and 1, 3 and 6 months after treatment
Foveal Avascular Zone (FAZ)
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in FAZ
Baseline and 1, 3 and 6 months after treatment
Lesion size
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in lesion size
Baseline and 1, 3 and 6 months after treatment
Macular volume
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in macular volume
Baseline and 1, 3 and 6 months after treatment
Venular saturation
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in venular saturation
Baseline and 1, 3 and 6 months after treatment
Arteriolar saturation
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in arteriolar saturation
Baseline and 1, 3 and 6 months after treatment
Retinal diameter
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in retinal diameter
Baseline and 1, 3 and 6 months after treatment
Venular diameter
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in venular diameter
Baseline and 1, 3 and 6 months after treatment
Retinal function
Time Frame: Baseline and 1, 3 and 6 months after treatment
Mean change from baseline in retinal function using full-field electroretinogram (ERG)
Baseline and 1, 3 and 6 months after treatment
Diabetic macular edema (DME)
Time Frame: Baseline and 1, 3 and 6 months after treatment
Incidence of diabetic macular edema (DME)
Baseline and 1, 3 and 6 months after treatment
Subjective experience of pain after treatment
Time Frame: Baseline and 1, 3 and 6 months after treatment
Study patients' subjective experience of pain after treatment using visual analog scale (VAS)
Baseline and 1, 3 and 6 months after treatment
Subjective overall experience of the treatment
Time Frame: Baseline and 1, 3 and 6 months after treatment
Study patients' subjective overall experience of the treatment using verbal scale (VS)
Baseline and 1, 3 and 6 months after treatment
Cost-effectiveness
Time Frame: Baseline and 1, 3 and 6 months after treatment

We intend to conduct a thorough cost-effectiveness analysis, comparing the single-session approach with the traditional multiple-session treatments.

This analysis will factor in direct medical costs, including the expenses related to the laser equipment, healthcare professionals' time, and the required clinical facilities. We will also consider indirect costs such as patient travel expenses and time taken off work.
Baseline and 1, 3 and 6 months after treatment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Vastra Gotaland Region

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Marita Andersson Grönlund, M.D. Prof, Göteborg University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 1, 2025

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 31, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 31, 2030

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 8, 2024

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 8, 2024

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
August 12, 2024

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 18, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 17, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
October 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • SMART-PRP

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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