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NCT Number: NCT06213649

Parasitic Ulcer Treatment Trial

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

Recruiting

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Key information

Conditions

Acanthamoeba Keratitis Amebiasis Corneal Diseases Corneal Ulcer Eye Diseases Eye Infections Eye Infections, Parasitic Infections Keratitis Parasitic Diseases Protozoan Infections

Age range

8 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 3

Primary location

Federal University of São Paulo, São Paulo, Brazil

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

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

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

Treatment and study plan

Polyhexamethylene biguanide (PHMB)

Drug

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.

Other names: Polyhexanide

Topical Corticosteroid

Drug

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

Other

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 outcomes

  1. Vision

    Time frame: 6 Months

    Best corrected visual acuity

Secondary outcomes

  1. Self-reported eye pain

    Time frame: 2 months

    Pain scale (Likert 11-point ordinal scale from 0 to 10; 0=no pain, 10=worst pain)

  2. Clinical Resolution

    Time frame: 12 months

    Time until clinical resolution (i.e., healed ocular surface and absence of inflammation)

  3. Multivariate Analysis

    Time frame: 6 Months

    The multivariate analysis will include the following outcomes measured at 6 months: best corrected visual acuity, corneal thinning on optical coherence tomography (OCT), scar density on Scheimpflug imaging, irregular astigmatism, glare, microbial clearance on confocal microscopy, pain score, time until clinical resolution

Study contacts

Contact information is provided by the study sponsor or research team.

Jeremy Keenan, MD, MPH

CONTACT

[email protected]

415-476-6323

Krisi Aromin

CONTACT

[email protected]

Sponsors and collaborators

Lead sponsor

Jeremy Keenan, MD, MPH

Other

Collaborators

  • Aravind Eye Care System
  • Baylor College of Medicine
  • Columbia University
  • Federal University of São Paulo
  • Johns Hopkins University
  • Moorfields Eye Hospital NHS Foundation Trust
  • National Eye Institute (NEI)
  • Oregon Health and Science University
  • University of Colorado Denver - Anschutz Medical Campus (UCD-AMC)
  • University of Florida
  • University of Illinois at Chicago
  • University of Iowa
  • University of Miami
  • University of Pennsylvania
  • University of Pittsburgh

Registry information

Acronym: PUTT

Important dates

Study start
2024
Primary completion
2029
Study completion
2029
First posted
Jan 19, 2024
Registry last updated
May 1, 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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