A Study to Investigate the Safety and Efficacy of K-321 Eye Drops After Simultaneous Cataract Surgery and Descemetorhexis in Participants With Fuchs Endothelial Corneal Dystrophy (FECD)

NCT05826353 | Completed Phase 3 FDA Drug

• 1 other identifier: K-321-303
• Study Type: interventional
• Target: 110
• Locations: 6 countries
• Sites: 43

Brief Summary

A study to assess the safety and efficacy of K-321 in participants with FECD after simultaneous cataract surgery and descemetorhexis.

Conditions

Fuchs Endothelial Corneal Dystrophy

Outcome Measures

Primary Outcomes (1)

• Time to improvement in best corrected (distance) visual acuity (BCVA) by ETDRS letter score during the first 12 weeks

  Baseline to Week 12

Secondary Outcomes (5)

• Time to improvement in best corrected (distance) visual acuity (BCVA) by ETDRS letter score during the first 12 weeks

  Baseline to Week 12

• Time to achievement in best corrected (distance) visual acuity (BCVA) by ETDRS letter score during the first 12 weeks

  Baseline to Week 12

• Central corneal Endothelial Cell Density (ECD) (cells/mm2) at Week 12

  Week 12

• Time to achievement of no corneal edema during the first 12 weeks

  Baseline to Week 12

• Time to exceed in BCVA pre-DSO ETDRS letter score during the first 12 weeks

  Baseline to Week 12

Study Arms (2)

K-321

EXPERIMENTAL

K-321 ophthalmic solution four times daily (QID) for 12 weeks followed by a two-week gradual dose taper phase and 38-week follow-up phase

Drug: Ripasudil

Placebo

PLACEBO COMPARATOR

Placebo ophthalmic solution QID for 12 weeks followed by a two-week gradual dose taper phase and 38-week follow-up phase

Drug: Placebo

Interventions

Ripasudil DRUG

K-321 ophthalmic solution

Also known as: K-321

K-321

Placebo DRUG

Placebo ophthalmic solution

Placebo

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Is at least 18 years old at the screening visit (Visit 1)
• Has a diagnosis of FECD at Visit 1

You may not qualify if:

• Is a female subject of childbearing potential and any of the following is true:
• is pregnant or lactating/breastfeeding, or
• is not surgically sterile, not post-menopausal (no menses for the previous 12 months), or not practicing an effective method of birth control as determined by the Investigator (eg, oral contraceptives, double barrier methods, hormonal injectable or implanted contraceptives, tubal ligation, or partner with vasectomy)

Sponsors & Collaborators

• Kowa Research Institute, Inc.: lead

Study Sites (43)

Keck Hospital of USC

Los Angeles, California, 90033, United States

Location

Macy Eye Center

Los Angeles, California, 90048, United States

Location

Byers Eye Institute at Stanford

Palo Alto, California, 94303, United States

Location

Sacramento Eye Consultants

Sacramento, California, 95815, United States

Location

Gorovoy MD Eye Specialists

Fort Myers, Florida, 33907, United States

Location

Bascom Palmer Eye Institute

Palm Beach Gardens, Florida, 33136, United States

Location

Grene Vision Group-Wichita

Wichita, Kansas, 67208, United States

Location

University of Kentucky

Lexington, Kentucky, 40508, United States

Location

W Kellogg Eye Center

Ann Arbor, Michigan, 48105, United States

Location

Verdier Eye Center

Grand Rapids, Michigan, 49546, United States

Location

Vance Thompson Vision - Omaha

Omaha, Nebraska, 68137, United States

Location

Eye Associates of New Mexico - Albuquerque - Northside

Albuquerque, New Mexico, 87109, United States

Location

NYU Langone Health

New York, New York, 10017, United States

Location

Vance Thompson Vision West Fargo

West Fargo, North Dakota, 58078, United States

Location

Cincinnati Eye Institute-1945 Cei Dr

Blue Ash, Ohio, 45242, United States

Location

University Hospitals Cleveland Medical Center - 11100 Euclid Ave

Cleveland, Ohio, 44106, United States

Location

Devers Eye Institute

Portland, Oregon, 97210, United States

Location

University of Texas Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

Houston Eye Associates

Houston, Texas, 77025, United States

Location

R and R Eye Research, LLC.

San Antonio, Texas, 78229, United States

Location

University of Wisconsin School of Medicine and Public Health

Madison, Wisconsin, 53705, United States

Location

Dr. Greg Moloney

Vancouver, British Columbia, 2000, Canada

Location

Prism Eye Institute - Mississauga-Oakville

Oakville, Ontario, L5L 1W8, Canada

Location

Precision Cornea Centre

Ottawa, Ontario, K1G 5L1, Canada

Location

Rigshospitalet Glostrup-Valdemar Hansens Vej 1-23

Glostrup Municipality, Capital, 2600, Denmark

Location

Aarhus Universitetshospital

Aarhus N, Central Jutland, 8200, Denmark

Location

Universitätsklinikum Heidelberg

Heidelberg, Baden-Wurttemberg, 91054, Germany

Location

Universitätsklinikum Tübingen

Tübingen, Baden-Wurttemberg, 72076, Germany

Location

Universitatsklinkum Erlangen-Ulmenweg 18

Erlangen, Bavaria, 91054, Germany

Location

Uniklinik Köln

Cologne, North Rhine-Westphalia, 50931, Germany

Location

Universitatsklinikum Dusseldorf

Düsseldorf, North Rhine-Westphalia, 40225, Germany

Location

Universität des Saarlandes

Homburg, Saarland, 66424, Germany

Location

LMU Klinikum der Universität

München, 81377, Germany

Location

Hospital Universitario Germans Trias i Pujol

Badalona, Barcelona, 08916, Spain

Location

Althaia Xarxa Assistencial Universitaria Manresa

Manresa, Barcelona, 17001, Spain

Location

Hospital Arruzafa

Córdoba, Córdoba, 14012, Spain

Location

Instituto Oftalmologico Fernandez Vega

Oviedo, Principality of Asturias, 33012, Spain

Location

Oftalvist - Barcelona

Barcelona, 08017, Spain

Location

Institut Catala de Retina (ICR)

Barcelona, 08022, Spain

Location

Instituto de Microcirugia Ocular

Barcelona, 08035, Spain

Location

The Royal Liverpool University Hospital

Liverpool, Lancashire, L7 8XP, United Kingdom

Location

Moorfields Eye Hospital

London, London, City of, EC1V 2PD, United Kingdom

Location

Royal Victoria Infirmary

Newcastle upon Tyne, Tyne and Wear, NE1 4LP, United Kingdom

Location

MeSH Terms

Conditions

Fuchs' Endothelial Dystrophy

Interventions

K-115

Condition Hierarchy (Ancestors)

Corneal Dystrophies, Hereditary; Corneal Diseases; Eye Diseases; Eye Diseases, Hereditary; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities

Study Officials

• Shona Pendse, MD, MMSc

  Kowa Pharma Development Co.

  STUDY CHAIR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 6, 2023
• First Posted: April 24, 2023
• Study Start: May 11, 2023
• Primary Completion: January 17, 2025
• Study Completion: October 24, 2025
• Last Updated: January 22, 2026

Record last verified: 2026-01

Locations

GB (3); ES (7); CA (3); US (21); DE (7); DK (2)