This Phase 3 clinical trial is a randomized, double-masked/assessor-masked, active-controlled study to be conducted on subjects affected by Acanthamoeba keratitis. The objective of the study is to evaluate the efficacy, safety, and tolerability of 0.08% PHMB ophthalmic solution + placebo (study drug) compared to the conventional 0.02% PHMB + 0.1% propamidine combination therapy.
The study will recruit 130 patients with confirmed Acanthamoeba keratitis and will be conducted at sites in the UK, Poland and Italy. Participants must be aged 14 or over, and fulfil the eligibility criteria. Half of the study volunteers will receive the study drug and half will receive the conventional therapy. The study will last until clinical resolution, to a maximum of one year.
Study sites are:
- Moorfields eye hospital, London UK
- Manchester Royal eye hospital, Manchester UK
- University hospital Southampton, UK
- San Raffaele hospital, Milan, Italy
- Azienda Ulss 12, Venice, Italy
- Medical University of Silesia, Katowice, Poland
Exclusion criteria include:
- Acanthamoeba keratitis diagnosis made “late” (>57 days).
- Concomitant presence of an ocular infection caused by viruses or fungi.
- Patients treated with any other known drug having effects on Acanthamoeba cysts prior to study entry, including biguanides (PHMB, chlorhexidine), diamidines (propamidine, hexamidine).
- Known or suspected allergy to biguanides, diamidines or intolerance to any other ingredient of the investigational treatments.
- Patients affected by immunodeficiency diseases or taking systemic immuno-suppressive therapy.