Recruiting
Phase 3

Parasitic Ulcer

Sponsor:

Jeremy Keenan, MD, MPH

Code:

NCT06213649

Conditions

Acanthamoeba Keratitis

Eligibility Criteria

Sex: All

Age: 8+

Healthy Volunteers: Not accepted

Interventions

Polyhexamethylene biguanide (PHMB)

Topical corticosteroid

Topical placebo

Study Details

Brief summary:

The Parasitic Ulcer Treatment Trial (PUTT) is a multi-center, parallel-group, randomized clinical trial. The purpose of this study is to determine whether including topical corticosteroids in a regimen for acanthamoeba keratitis (AK) will improve vision. Patients presenting to all enrollment centers with evidence of acanthamoeba keratitis will be eligible for the trial if there is evidence of ocular inflammation after 4 weeks of anti-amoebic therapy. Those who agree to participate will be randomized to one of two treatment groups:

  • Group 1: Topical corticosteroid
  • Group 2: Topical placebo

Conditions

Acanthamoeba Keratitis

Study ID

NCT06213649

Start date

Jul 1, 2024

Status verified date

Apr, 2026

Completion date

Jul, 2029

Anticipated

Primary completion date

Jul, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 8+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • AK on at least one of the following: culture, smear, PCR, shotgun sequencing, biopsy, or confocal microscopy
  • Ocular inflammation after 1 month of anti-amoebic treatment, defined as conjunctival, corneal, episcleral, or anterior chamber inflammation

Exclusion Criteria:

  • Evidence or history of interstitial keratitis
  • Known herpetic keratitis, as determined from history, exam, or microbiological testing
  • Known fungal keratitis, as demonstrated from corneal scrapings
  • Corneal perforation or impending corneal perforation
  • Prior therapeutic keratoplasty for acanthamoeba keratitis
  • Unwillingness or inability to follow-up
  • No light perception in the affected eye
  • Known hypertensive response to steroids
  • Corticosteroid allergy
  • Concurrent treatment with systemic corticosteroids
  • Concurrent granulomatous amoebic encephalitis

Study Design

Enrollment

232 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Topical steroids

Participants in this arm will receive anti-amoebic therapy plus topical steroids.

placebo comparator: Topical placebo

Participants in this arm will receive anti-amoebic therapy plus topical placebo.

Interventions

Polyhexamethylene biguanide (PHMB)

PHMB is a cationic antiseptic agent used for topical treatment of acanthamoeba keratitis (AK). Both treatment groups will take PHMB at least 4 times daily while on the allocated study drug.

Topical corticosteroid

Dexamethasone sodium phosphate, 0.1% ophthalmic solution will be administered 4 times daily for 4 weeks, then 2 times daily for 2 weeks, then 1 time daily for 2 weeks.

Topical placebo

An artificial tear ophthalmic solution will be administered 4 times daily for 4 weeks, then 2 times daily for 2 weeks, then 1 time daily for 2 weeks.

Primary outcome measure

  • Vision [ Time Frame: 6 Months ]

Central Contacts and Locations

Central contacts

Jeremy Keenan, MD, MPH

415-476-6323jeremy.keenan@ucsf.edu

Krisi Aromin

krisianne.aromin@ucsf.edu

Locations

University of California, San Francisco

Recruiting

San Francisco, California, United States, 94158

Contacts

Krisianne Aromin

krisianne.aromin@ucsf.edu

Principal Investigator:

Jeremy Keenan, MD, MPH

University of Colorado Anschutz

Recruiting

Aurora, Colorado, United States, 80045

Contacts

Travis Redd

7208482020travis.redd@cuanschutz.edu

University of Florida

Recruiting

Gainesville, Florida, United States, 32605

University of Miami

Recruiting

Miami, Florida, United States, 33136

University of Illinois, Chicago

Recruiting

Chicago, Illinois, United States, 60612

University of Iowa

Recruiting

Iowa City, Iowa, United States, 52242

Johns Hopkins University

Recruiting

Baltimore, Maryland, United States, 21287

Columbia University

Recruiting

New York, New York, United States, 10032

Oregon Health and Science University

Recruiting

Portland, Oregon, United States, 97239

University of Pennsylvania

Recruiting

Philadelphia, Pennsylvania, United States, 19104

University of Pittsburgh Medical Center

Recruiting

Pittsburgh, Pennsylvania, United States, 15219

Contacts

Gaurav Prakash, MD

412-647-2200prakashg@upmc.edu

Baylor College of Medicine

Recruiting

Houston, Texas, United States, 77030

Contacts

Alejandro Arboleda, MD MS

713-798-5143alejandro.arboleda@bcm.edu

University of Washington

Recruiting

Seattle, Washington, United States, 98104

Contacts

Minh Nguyen, MD

206-543-7250minhng88@uw.edu

More Information

Sponsor

Jeremy Keenan, MD, MPH

Last update posted

May 1, 2026

Last verified

Apr, 2026

Keywords

  • corneal ulcer
  • steroids

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-08. This information was provided to ClinicalTrials.gov by Jeremy Keenan, MD, MPH on 2026-05-01.