Diabetic Macular EdemaPhase 3NCT06172257
A Pivotal Safety and Efficacy Study of OCS-01 Eye Drops in Participants With Diabetic Macular Edema (DIAMOND 2)
A Phase 3 study testing Dexamethasone ophthalmic suspension (OCS-01) in people with Diabetic Macular Edema, run by Oculis at 62 sites in 4 countries.
Trial summary
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). Read more about this study
- Who is it for?
- Ages 18 to 85 years
- Conditions the study is for
- Diabetic Macular Edema
- What is being tested?
- Dexamethasone ophthalmic suspension (OCS-01)
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 401 participants
- Where
- 62 sitesin 4 countries
- Study dates
- 15 Mar 2024to 2 Apr 2026
- Phase
- Phase 3
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 85 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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 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 screening (Visit 1).
Who cannot join
- 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.
Trial locations and contacts
62 sites in 4 countries.
62 sites in 4 countries
United States42 sites
California Retina Consultants
Bakersfield, California, 93309
Retina Consultants of Texas
Bellaire, Texas, 77401
Ophthalmic Consultants of Boston
Boston, Massachusetts, 02114
Sibia Eye Institute
Boynton Beach, Florida, 11195
Star Retina
Burleson, Texas, 76028
Blue Ocean Clinical Research
Clearwater, Florida, 33761
Advanced Research
Coral Springs, Florida, 33067
Retina Specialists of Colorado
Denver, Colorado, 80210
Erie Retina Research
Erie, Pennsylvania, 16507
Retina Group of Florida
Fort Lauderdale, Florida, 33308
Charles Retina Institute
Germantown, Tennessee, 38138
Associated Retina Consultants
Gilbert, Arizona, 85297
Cumberland Valley Retina Consultants
Hagerstown, Maryland, 21740
Mid Atlantic Retina Specialists
Hagerstown, Maryland, 21740
VitreoRetinal Consultants of NY
Hauppauge, New York, 11788
Houston Eye Associates, North Loop
Houston, Texas, 77025
Retina Associates of Southern California
Huntington Beach, California, 92647
Mississippi Retina Associates
Jackson, Mississippi, 90033
East Coast Institute for Research
Jacksonville, Florida, 32256
Eye Care Center of Northern Colorado
Longmont, Colorado, 80503
Piedmont Eye Center
Lynchburg, Virginia, 24502
Marietta Eye Clinic
Marietta, Georgia, 30060
Retina Consultants of Southwest Florida
Naples, Florida, 33912
Tennessee Retina
Nashville, Tennessee, 37203
Illinois Retina Associates
Oak Park, Illinois, 60304
Stanford Byers Eye Institute
Palo Alto, California, 94303
Georgia Retina
Peachtree City, Georgia, 30269
Vision Research Solutions in Philadelphia
Philadelphia, Pennsylvania, 19141
Associated Retina Consultants
Phoenix, Arizona, 85020
Retinal Consultants of Arizona - Phoenix North
Phoenix, Arizona, 85053
Sierra Eye Associates
Reno, Nevada, 89502
Austin Retina Associates
Round Rock, Texas, 78681
Retinal Consultants Medical Group, Inc
Sacramento, California, 95825
Retinal Consultants Medical Group
Sacramento, California, 95841
San Antonio Eye Center - Downtown Clinic
San Antonio, Texas, 78215
Medical Center Ophthalmology Associates
San Antonio, Texas, 78240
California Retina Consultants
Santa Barbara, California, 93103
Island Retina
Shirley, New York, 11967
Macula Retina Vitreous Center
Torrance, California, 90503
Tyler Retina Consultants
Tyler, Texas, 75703
Palmetto Retina Center
West Columbia, South Carolina, 29169
Vitreoretinal Consultants of NY
Westbury, New York, 11590
Argentina13 sites
Fundacion Zambrano
Buenos Aires, Buenos Aires, 1023
Oftalmos - Instituto Oftalmológico de Alta Complejidad
Buenos Aires, Buenos Aires, C1120 AAN
Centro De Ojos Loria Srl
CABA, Buenos Aires, 1663
Centro Privado de Ojos
CABA, Buenos Aires, 1663
Organizacion Medica De Investigacion
CABA, Buenos Aires, C1015
Buenos Aires Macula (BAM) Clinical Research
CABA, Buenos Aires, C1061AAE
Charles Centro Oftalmológico
Ciudad Autónoma de Buenos Aires, Buenos Aires, C1008
Centro Privado de Ojos Romagosa
Córdoba, Córdoba Province, 5000
Instituto de Microcirugía Ocular Córdoba (IMOC)
Córdoba, Córdoba Province, X5016KEH
Oftar Mendoza - Centro Privado de Oftalmología en Mendoza Capital
Mendoza, Mendoza Province, M5500
Grupo Laser Vision
Rosario, Santa Fe Province, S2000 PRB
Oftalmologìa Global
Rosario, Santa Fe Province, S2000
Centro de la Vision Dr. Kolton
Salta, Salta Province, A4400
India6 sites
Rising Retina Clinic
Ahmedabad, Gujarat, 380015
Narayana Nethralaya
Bangalore, Karnataka, 560010
Lotus Eye Hospital and Institute
Coimbatore, Tamil Nadu, 641014
St. Theresa's Hospital
Hyderabad, Telangana, 500038
Agrawal Hospital
Jaipur, Rajasthan, 302004
GSVM Medical College
Kanpur, Uttar Pradesh, 208005
About this study
Official title: A Phase 3 Double-masked, Randomized, Multicenter Study of the Efficacy and Safety of OCS 01 Eye Drops in Subjects With Diabetic Macular Edema
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).
Read the detailed description
A Phase 3 Pivotal Double-masked, Randomized, Vehicle-controlled, Multicenter Study of the Efficacy and Safety of OCS 01 Eye Drops in participants with Diabetic Macular Edema
- Conditions
- Diabetic Macular Edema
- Being tested
- Dexamethasone ophthalmic suspension (OCS-01), Vehicle
- Keywords
- Topical ophthalmic suspension, Eye drop
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Dexamethasone ophthalmic suspension (OCS-01)Drug
Also called Dexamethasone
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).
VehicleDrug
Also called Placebo
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 46 weeks (maintenance phase).
| Study group | Role | What they receive |
|---|---|---|
| OCS-01 | Experimental | dexamethasone ophthalmic suspension,1.5% [15 mg/mL] Receives: Drug: Dexamethasone ophthalmic suspension (OCS-01) |
| Vehicle ophthalmic suspension | Placebo comparator | Vehicle of OCS-01 Receives: Drug: Vehicle |
What is being measured
The primary outcome is the main question the study is designed to answer.
Mean Change from Baseline in BCVA (Best Corrected Visual Acuity)
Assessed using ETDRS (Early Treatment Diabetes Retinopathy Study) letters score: higher numbers on the ETDRS chart representing better visual acuity.
Measured: Week 52
Secondary outcomes (3)
Percentage of Participants With a 3-line or Greater Gain in BCVA
BCVA will be assessed using ETDRS letters score: higher numbers on the ETDRS chart representing better visual acuity.
Measured: Baseline, Week 52
Mean Change in BCVA
BCVA will be assessed using ETDRS letters score: higher numbers on the ETDRS chart representing better visual acuity.
Measured: Baseline, Week 12 and Week 24
Mean Change in Central Subfield Thickness (CST)
CST will be measured by spectral domain optical coherence tomography (SD-OCT)
Measured: Baseline, Week 52
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Dec 2023
- Study start15 Mar 2024
- Primary completion2 Apr 2026
- Study completion2 Apr 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Diabetic Macular EdemaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 401 participants (actual)
Sponsor and investigators
- Lead sponsor
- Oculis
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Diana Do, MD, Principal investigator, Stanford Byers Eye Institute
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06172257
- Sponsor's protocol ID
- DX221
- Status last verified
- Apr 2026
- First submitted
- 7 Dec 2023
- Last updated
- 1 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 1 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3 Double-masked, Randomized, Multicenter Study of the Efficacy and Safety of OCS 01 Eye Drops in Subjects With Diabetic Macular Edema
- ClinicalTrials.gov ID
- NCT06172257
- Acronym / sponsor ID
- DX221
- Conditions
- Diabetic Macular Edema
- Keywords
- Topical ophthalmic suspension, Eye drop
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 401 participants (actual)
- Lead sponsor
- OculisIndustry (pharma, biotech, devices)
- Study start
- 15 Mar 2024 (actual)
- Primary completion
- 2 Apr 2026 (actual)
- Study completion
- 2 Apr 2026 (actual)
- First posted
- 15 Dec 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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).
Detailed description
A Phase 3 Pivotal Double-masked, Randomized, Vehicle-controlled, Multicenter Study of the Efficacy and Safety of OCS 01 Eye Drops in participants with Diabetic Macular Edema
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| OCS-01 | Experimental | Drug: Dexamethasone ophthalmic suspension (OCS-01)dexamethasone ophthalmic suspension,1.5% [15 mg/mL] |
| Vehicle ophthalmic suspension | Placebo comparator | Drug: VehicleVehicle of OCS-01 |
Who may qualify
- Ages
- 18 to 85 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- 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 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 screening (Visit 1).
Key exclusion criteria (3 listed)
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Dexamethasone ophthalmic suspension (OCS-01)Also: DexamethasoneParticipants 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). | Drug | OCS-01 |
| VehicleAlso: PlaceboParticipants 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). | Drug | Vehicle ophthalmic suspension |
Primary outcome
Mean Change from Baseline 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.
3 secondary outcomes
Percentage of Participants With a 3-line or Greater Gain in BCVA
Time frame: Baseline, Week 52
Mean Change in BCVA
Time frame: Baseline, Week 12 and Week 24
Mean Change in Central Subfield Thickness (CST)
Time frame: Baseline, Week 52
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 1 May 2026.
- Individual participant dataSharing planned: No
Related trials for Diabetic Macular Edema
Active, not recruitingObservational study
Real World Evidence in China: Faricimab Use in Diabetic Macular Edema, Retinal Vein Occlusion, and Neovascular Age-Related Macular Degeneration (The Farseeing Study)
Diabetic Macular Edema, Neovascular Age-related Macular Degeneration
Active, not recruitingPhase 2
Long-Term Follow-Up Study of RGX-314 Administered in the Suprachoroidal Space for Participants With and Without Diabetic Retinopathy
Diabetic Retinopathy, DR
RecruitingPhase 3
A Phase 3 Trial for Intravitreal Injection of 4D-150 in Adults With Diabetic Macular Edema (DME).
Diabetic Macular Edema (DME)
RecruitingPhase 2
Oral N-Acetylcysteine on Diabetic Macular Edema
Diabetic Macular Edema (DME)
Active, not recruitingPhase 3
COMO: A Phase 3 Randomized, Double-Masked Study Comparing the Efficacy of EYP-1901 Against Aflibercept in DME
Diabetic Macular Edema, DME
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Diana Do, MD principal investigator
Stanford Byers Eye Institute
62 sites in 4 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Dexamethasone ophthalmic suspension (OCS-01) in people with Diabetic Macular Edema, run by Oculis at 62 sites in 4 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 1 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 62 sites in United States, Argentina, India, Puerto Rico. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Mean Change from Baseline in BCVA (Best Corrected Visual Acuity) (time frame: Week 52). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 1 May 2026.