Parasitic Ulcer Treatment Trial Pilot

University of California San Francisco (UCSF)

Status and phase: Active, not recruiting; Phase 2

Conditions: Acanthamoeba Keratitis

Treatments: Drug: Hydroxypropyl Methylcellulose; Drug: Chlorhexidine; Drug: Povidone-Iodine; Drug: Prednisolone Sodium Phosphate

Study type: Interventional

Funder types: Other

Identifiers

NCT03484507

UCSF-IRB-17-23895

Details and patient eligibility

About

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.

Full 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.

Enrollment: 49 patients

Sex: All

Ages: 13+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

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)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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49 participants in 5 patient groups, including a placebo group

Chlorhexidine monotherapy

Active Comparator group

Description:

Topical chlorhexidine 0.04%

Treatment:

Drug: Chlorhexidine

Chlorhexidine plus povidone iodine

Experimental group

Description:

Topical chlorhexidine 0.04% plus povidone iodine 2.5%

Treatment:

Drug: Chlorhexidine

Drug: Povidone-Iodine

Early corticosteroids

Experimental group

Description:

Topical prednisolone sodium phosophate 1% for weeks 4-11

Treatment:

Drug: Prednisolone Sodium Phosphate

Drug: Prednisolone Sodium Phosphate

Late corticosteroids

Experimental group

Description:

Artificial tears for weeks 4-5, then topical prednisolone sodium phosophate 1% for weeks 6-11

Treatment:

Drug: Hydroxypropyl Methylcellulose

Drug: Prednisolone Sodium Phosphate

Drug: Hydroxypropyl Methylcellulose

Drug: Prednisolone Sodium Phosphate

Placebo

Placebo Comparator group

Description:

Artificial tears for weeks 4-11

Treatment:

Drug: Hydroxypropyl Methylcellulose

Drug: Hydroxypropyl Methylcellulose