Polihexanide (PHMB) Eye Drops in Patients Affected by Acanthamoeba Keratitis

Phase 3

Completed

Interventions: Drug: PHMB 0.08%
Drug: Propamidine 0.1%
Drug: placebo
Drug: PHMB 0.02%

Brief Summary: Prospective randomized study to evaluate the efficacy, safety and tolerability of 0.08% polihexanide (PHMB) eye drops in patients affected by acanthamoeba keratitis.

130 subjects were assigned to one of the following 2 treatment groups: Group 1: 0.08% polihexanide (PHMB) + placebo Group 2: 0.02% polihexanide (PHMB) + 0.1% propamidine

Detailed Description: This was a randomized, assessor-masked, active-controlled, multiple center, parallel-group phase 3 study to evaluate the efficacy, safety and tolerability of 0.08% polihexanide (PHMB) ophthalmic solution compared to the conventional 0.02% polihexanide (PHMB) + 0.1% propamidine in patients affected by acanthamoeba keratitis.

The study was designed as a superiority study with the possibility to test for non-inferiority if the superiority hypothesis was not met (CPMP/EWP/482/99).The study consisted of an eligibility screening visit, a treatment period including monthly follow-up visits until a clinical resolution was obtained (within a maximum of 1 year), followed by 2 post-treatment off-therapy visits (30 and 90 days after treatment discontinuation). 130 subjects with confirmed diagnosis of acanthamoeba keratitis (clinical signs plus positive confocal microscopy findings) were assigned to one of the following treatment groups in a ratio of 1:1.

Group 1: 0.08% PHMB + placebo Group 2: 0.02% PHMB + 0.1% propamidine

Recruitment & Eligibility

Inclusion Criteria

willing to give informed consent
man or woman of any race and ≥12 years of age
able to understand and willing to comply with study procedures, restrictions and requirements
Clinical findings consistent with Acanthamoeba keratitis
Confocal microscopy findings consistent with Acanthamoeba keratitis
The following previous treatments for Acanthamoeba keratitis are eligible: antibiotics, antiviral and antifungal drugs, antiinflammatory drugs
Females of childbearing potential will be included if they are either sexually inactive or using one highly effective contraceptive
Females of childbearing potential agree to remain sexually inactive or to keep the same birth control method for at least 28 days following the last study drug dose
A female of non-childbearing potential must have undergone one sterilization procedures at least 6 months prior to the first study drug dose
A non-vasectomized male subject agrees to use a condom with spermicide or abstain from sexual intercourse during the study until 90 days beyond the last dose of study drug and the female partner agrees to comply with inclusion 7 or 8. For a vasectomized male who has had his vasectomy 6 months or more prior to study start, it is required that they use a condom during sexual intercourse. A male who has been vasectomized less than 6 months prior to study start must follow the same restrictions as a non-vasectomized male.
If male, they must agree not to donate sperm from the first study drug dose until 90 days after dosing

Exclusion Criteria

Subject with documented history and/or clinical signs of concomitant presence of an ocular infection caused by viruses (herpes simplex virus [HSV]) or fungi.
Subject treated with drugs having effects on Acanthamoeba cysts prior to study entry, including biguanides (PHMB, chlorhexidine) and diamidines (propamidine, hexamidine).
Subjects requiring systemic immunosuppression for Acanthamoeba associated scleritis.
Subjects requiring urgent surgical intervention for advanced Acanthamoeba keratitis in either eye (e.g., for advanced corneal thinning/melting etc.).
Subject with known or suspected allergy to biguanides, diamidines or intolerance to any other ingredient of the investigational treatments.
Subject affected by immunodeficiency diseases or taking systemic immunosuppressive therapy.
Subject with a major systemic disease or other illness that would, in the opinion of the investigator, compromise subject's safety or interfere with the collection or interpretation of study results.
If female, pregnancy, planned pregnancy, or breast-feeding
Subject is participating in another interventional clinical study with an experimental or unapproved/unlicensed therapy or has participated in another interventional clinical study within 4 weeks prior to this study.

Arm && Interventions

Group	Intervention	Description
PHMB 0.08% plus placebo	PHMB 0.08%	polihexanide (PHMB) 0.08% and placebo were administered in the affected eye until clinical resolution for a maximum of 12 months
PHMB 0.08% plus placebo	placebo	polihexanide (PHMB) 0.08% and placebo were administered in the affected eye until clinical resolution for a maximum of 12 months
PHMB 0.02% plus propamidine 0.1%	Propamidine 0.1%	polihexanide (PHMB) 0.02% and propamidine 0.1% were administered in the affected eye until clinical resolution for a maximum of 12 months
PHMB 0.02% plus propamidine 0.1%	PHMB 0.02%	polihexanide (PHMB) 0.02% and propamidine 0.1% were administered in the affected eye until clinical resolution for a maximum of 12 months

Primary Outcome Measures

Name	Time	Method
Clinical Resolution Rate	12 months	Percentage of patients cured 30 days after discontinuing all study therapies, within 12 months of randomization

Secondary Outcome Measures

Name	Time	Method
Time to Cure	maximum 12 months	Time needed to reach a clinical resolution
Visual Acuity	maximum 12 months	Final visual acuity (best corrected)

Locations (6): San Giovanni and Paolo Hospital
🇮🇹
Venice, Italy
University Hospital Southampton
🇬🇧
Southampton, United Kingdom
San Raffaele Hospital
🇮🇹
Milano, Italy
Moorfields Hospital
🇬🇧
London, United Kingdom
University Clinical Center Medical University of Silesia
🇵🇱
Katowice, Poland
Manchester Royal Eye Hospital
🇬🇧
Manchester, United Kingdom