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Completed

NCT Number: NCT05066997

A Pivotal Safety and Efficacy Study of OCS-01 Eye Drops in Participants With Diabetic Macular Edema (DIAMOND 1)

The primary objective of this study is to evaluate the efficacy and safety of the topical ophthalmic administration of OCS- 01 as compared to Vehicle in participants with Diabetic Macular Edema (DME).

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Key information

Conditions

Diabetic Macular Edema

Age range

18 year–85 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2 / Phase 3

Primary location

HKU Eye Centre, Hong Kong

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About this study

A Phase 2/3 Pivotal Double-masked, Randomized, Vehicle-controlled, 2 stage, Multicenter Study of the Efficacy and Safety of OCS-01 Eye Drops in Participants with Diabetic Macular Edema

Stage 1: To select a dose and dosing regimen for OCS-01 in participants with DME and evaluate the efficacy and safety of OCS-01 as compared to Vehicle in participants with DME.

Stage 2: To evaluate the efficacy and safety of OCS-01 as compared to Vehicle at Week 52 in participants with DME.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

(selection) - Stage 1:

  • Have a signed informed consent form before any study-specific procedures are performed.
  • Have DME with presence of intraretinal and/or subretinal fluid in the study eye, with central subfield thickness (CST) of ≥310 µm by SD-OCT at screening (Visit 1) (as assessed by an independent reading center).
  • Have a documented diagnosis of type 1 or type 2 diabetes mellitus at Visit 1 (Screening).

Inclusion criteria

(selection) - Stage 2:

  • Have a signed informed consent form before any study-specific procedures are performed.
  • Have DME with presence of intraretinal and/or subretinal fluid in the study eye, with central subfield thickness (CST) of ≥310 µm by SD-OCT at screening (Visit 1) (as assessed by an independent reading center).
  • Have a documented diagnosis of type 1 or type 2 diabetes mellitus prior to Visit 1 (Screening).

Exclusion criteria

(selection) - Stage 1 and Stage 2:

  • Have macular edema considered to be because of a cause other than DME.
  • Have a decrease in BCVA because of causes other than DME.
  • Have a known history of significant macular ischemia which would prevent gain in visual acuity in the study eye.

Treatment and study plan

Dexamethasone ophthalmic suspension (OCS-01)

Drug

Stage 1: Participants will be dosed with one eye drop of OCS-01 6 times per day for 6 weeks (induction phase) followed by 3 times per day for 6 weeks (maintenance phase).

Stage 2: Participants will be dosed with one eye drop of OCS-01 6 times per day for 6 weeks (induction phase) followed by 3 times per day for 46 weeks (maintenance phase).

Other names: Dexamethasone

Vehicle

Drug

Stage 1: Participants will be dosed with one eye drop of vehicle 6 times per day for 6 weeks (induction phase) followed by 3 times per day for 6 weeks (maintenance phase).

Stage 2: Participant will be dosed with one eye drop of vehicle 6 times per day for 6 weeks (induction phase) followed by 3 times per day for 46 weeks (maintenance phase).

Other names: Placebo

Primary outcomes

  1. Mean Change in BCVA (Best Corrected Visual Acuity)

    Time frame: Week 52

    Assessed using ETDRS (Early Treatment Diabetes Retinopathy Study) letters score: higher numbers on the ETDRS chart representing better visual acuity

Secondary outcomes

  1. Percentage of Participants with a 3-line or Greater Gain in BCVA

    Time frame: Baseline, Week 52

    BCVA will be assessed by ETDRS letters score: higher numbers on the ETDRS chart representing better visual acuity.

  2. Mean Change in BCVA

    Time frame: Baseline, Week 12 and Week 24

    BCVA will be assessed using ETDRS letters score: higher numbers on the ETDRS chart representing better visual acuity.

  3. Mean Change in Central Subfield Thickness (CST)

    Time frame: Baseline, Week 52

    CST will be measured by SD-OCT.

Other outcomes

  1. Number of Participants With Treatment Emergent Adverse events (TEAEs)

    Time frame: Up to Week 52

    An adverse event (AE) is defined as any untoward medical occurrence in a clinical investigation participant. TEAEs are those AEs that occur after administration of the study product and are therefore temporally associated with the use of the study product.

Sponsors and collaborators

Lead sponsor

Oculis

Industry

Registry information

Official study title

A Phase 2/3 Double-Masked, Randomized, 2 Stage, Multicenter Study of the Efficacy and Safety of OCS-01 Eye Drops in Subjects With Diabetic Macular Edema

Important dates

Study start
2021
Primary completion
2026
Study completion
2026
First posted
Oct 4, 2021
Registry last updated
May 5, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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