Parasitic Ulcer Treatment Trial Pilot

February 2, 2024 updated by: University of California, San Francisco
This is a study of optimal treatments for acanthamoeba keratitis. In the first part of the study, participants will be randomized to chlorhexidine monotherapy or chlorhexidine plus povidone iodine. After four weeks of therapy, participants will be re-randomized to early corticosteroids, later corticosteroids, or placebo.

Study Overview

Detailed Description

Acanthamoeba keratitis is a rare eye infection that is difficult to treat. The mainstay of therapy is a biguanide agent such as chlorhexidine, though recent studies have found povidone iodine to be effective for killing acanthamoeba organisms in vitro. Thus, we randomize participants to topical chlorhexidine 0.04% monotherapy (i.e., routine care) versus topical chlorhexidine 0.04% plus topical poviodine iodine 2.5%. The primary outcome is clearance of acanthamoeba from the ocular surface at 4 weeks.

The role of topical corticosteroids in acanthamoeba keratitis is controversial. Topical corticosteroids can promote growth of acanthamoeba, but may also reduce inflammation and vision-threatening complications of infection. Here, we randomize participants who have completed a course of anti-amoebic therapy to one of three groups: early prednisolone sodium phosphate 1% (started at 4 weeks), late prednisolone sodium phosphate 1% (started at 6 weeks) or placebo (started at 4 weeks). The primary outcome will be visual acuity at 6 months.

Study Type

Interventional

Enrollment (Actual)

49

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Tamil Nadu
      • Coimbatore, Tamil Nadu, India
        • Aravind Eye Hospital
      • Madurai, Tamil Nadu, India
        • Aravind Eye Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

13 years and older (Child, Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Trial 1 Inclusion Criteria:

  • Smear or culture positive for acanthamoeba
  • Age 13 years or greater

Trial 1 Exclusion Criteria:

  • Interstitial or viral keratitis on history or examination
  • Corneal perforation
  • Therapeutic keratoplasty for acanthamoeba keratitis
  • Unwillingness or inability to follow-up (e.g., living too far from hospital)

Trial 2 Inclusion Criteria

  • Smear or culture positive for acanthamoeba, with 4 weeks of anti-amoebic treatment
  • Age 13 years or greater
  • Willing to participate in study

Trial 2 Exclusion Criteria

  • Interstitial or viral keratitis on history or examination
  • Fungus identified on culture and smear after 2 weeks of anti-amoebic treatment
  • Corneal perforation
  • Therapeutic keratoplasty for acanthamoeba keratitis
  • Unwillingness or inability to follow-up (e.g., living too far from hospital)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Chlorhexidine monotherapy
Topical chlorhexidine 0.04%
1 drop half-hourly for days 1-2, then hourly for days 3-6, then 8 times daily until the 4-week visit
Experimental: Chlorhexidine plus povidone iodine
Topical chlorhexidine 0.04% plus povidone iodine 2.5%
1 drop half-hourly for days 1-2, then hourly for days 3-6, then 8 times daily until the 4-week visit
1 drop half-hourly for days 1-2, then hourly for days 3-6, then 8 times daily until the 4-week visit
Experimental: Early corticosteroids
Topical prednisolone sodium phosophate 1% for weeks 4-11
1 drop 4 times daily for weeks 4-9, then 2 times daily for weeks 10-11
1 drop 4 times daily for weeks 6-9, then 2 times daily for weeks 10-11
Experimental: Late corticosteroids
Artificial tears for weeks 4-5, then topical prednisolone sodium phosophate 1% for weeks 6-11
1 drop 4 times daily for weeks 4-9, then 2 times daily for weeks 10-11
1 drop 4 times daily for weeks 6-9, then 2 times daily for weeks 10-11
1 drop 4 times daily for weeks 4-9, then 2 times daily for weeks 10-11
1 drop 4 times daily for weeks 4-5
Placebo Comparator: Placebo
Artificial tears for weeks 4-11
1 drop 4 times daily for weeks 4-9, then 2 times daily for weeks 10-11
1 drop 4 times daily for weeks 4-5

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Trial 1: Microbial clearance
Time Frame: 4 weeks
Acanthamoeba culture
4 weeks
Trial 2: Best spectacle corrected visual acuity
Time Frame: 6 months
6 months

Secondary Outcome Measures

Outcome Measure
Time Frame
Trial 1: Best spectacle corrected visual acuity
Time Frame: 4 weeks
4 weeks
Trial 1: Time to re-epithelialization
Time Frame: 4 weeks
4 weeks
Trial 1: Clinical cure
Time Frame: 4 weeks
4 weeks
Trial 2: Time to clinical cure
Time Frame: 6 months
6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Jeremy D Keenan, MD, University of California, San Francisco

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 1, 2018

Primary Completion (Estimated)

December 31, 2024

Study Completion (Estimated)

December 31, 2024

Study Registration Dates

First Submitted

March 24, 2018

First Submitted That Met QC Criteria

March 24, 2018

First Posted (Actual)

March 30, 2018

Study Record Updates

Last Update Posted (Estimated)

February 6, 2024

Last Update Submitted That Met QC Criteria

February 2, 2024

Last Verified

February 1, 2024

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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