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Recruiting Phase 2 NCT05426044

NCT05426044 Metformin as a Neuroprotective Therapy for Glaucoma

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Clinical Trial Summary
NCT ID NCT05426044
Status Recruiting
Phase Phase 2
Sponsor Christopher Kai Shun Leung
Condition Glaucoma
Study Type INTERVENTIONAL
Enrollment 125 participants
Start Date 2025-06-01
Primary Completion 2027-12-31

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
MetforminPlacebo

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

In Phase 2, researchers evaluate early signs of effectiveness. You may be randomized to receive the active treatment or a comparator. Monitoring continues closely.

This trial targets 125 participants in total. It began in 2025-06-01 with a primary completion date of 2027-12-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Glaucoma, a chronic degenerative disease of the optic nerve, is the leading cause of irreversible blindness worldwide. Although lowering the intraocular pressure (IOP) has been shown to be effective to slow optic nerve degeneration, a significant portion of glaucoma patients continue to develop progressive loss in vision despite adequate control of IOP. Development of neuroprotective therapy to prevent optic nerve degeneration by mechanisms other than IOP- lowering is critical to reduce the burden of glaucoma blindness. With 76 million glaucoma patients in 2020 worldwide, the need to investigate neuroprotection for glaucoma is pressing. While metformin is a widely adopted oral hypoglycemic medication for treatment of type 2 diabetes mellitus (DM), increasing evidence from clinical studies has shown that metformin can decrease the risk of many age-related diseases including neurodegenerative diseases. In a retrospective study of 150,016 patients with DM, those taking metformin at \>1500mg/day had a 25% reduced risk of development of open-angle glaucoma than those who took no metformin. Metformin has a high safety profile. The investigators aim to investigate whether metformin can be repurposed to a neuroprotective therapy for glaucoma patients in a randomized controlled trial. The investigators propose to conduct a 24-month, double-blind, placebo-controlled, parallel group, randomizing 125 primary open angle glaucoma patients who have progressive retinal nerve fiber layer (RNFL) and/or ganglion cell inner plexiform layer (GCIPL) thinning in at least one eye, as determined by optical coherence tomography Trend-based Progression Analysis (TPA) or Guided Progression Analysis (GPA), to receive metformin 1500mg/day or placebo. All patients will be followed up at 2-month intervals for IOP, RNFL thickness, and visual field (VF) measurements. The objectives are to compare (1) the rates of change of average RNFL thickness (primary outcome measure), and (2) the rates of change of VF mean deviation (MD) (secondary outcome measure) between treatment groups. The investigators hypothesize that patients treated with metformin have a slower rate of RNFL thinning, and a slower rate of VF MD decline compared with those treated with placebo at similar levels of IOP over the 24-month follow-up. The proposed study has the potential to mark a paradigm shift in the management of glaucoma patients by demonstrating that neuroprotection is attainable with metformin, which will alleviate the increasing burden of glaucoma blindness in China and other Asian countries where glaucoma patients with normal levels of IOP are prevalent. Furthermore, it will inform and impact the study design in future neuroprotection trials which can expedite the development of neuroprotective therapy for glaucoma.

Eligibility Criteria

Inclusion Criteria: * age ≥18 years * best corrected VA ≥20/40 * IOP ≤24mmHg at the screening and baseline visits * progressive RNFL and/or GCIPL thinning by TPA or GPA over the past 3 years in at least one eye. Exclusion Criteria: * patients with DM, kidney or liver diseases * pathological myopia * cognitive impairment (e.g. Alzheimer's disease) * diseases that may cause visual field loss or optic disc abnormalities other than glaucoma * inability to perform reliable visual field * suboptimal quality of OCT images. Both eyes of a patient will be included in the analysis if both eyesare eligible for inclusion.

Contact & Investigator

Central Contact

Christopher LEUNG, MD

✉ cleung21@hku.hk

📞 (852)3962-1405

Principal Investigator

Christopher LEUNG, MD

PRINCIPAL INVESTIGATOR

The University of Hong Kong

Frequently Asked Questions

Who can join the NCT05426044 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Glaucoma. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT05426044 trial and what does that mean for participants?

Phase 2 trials evaluate whether the treatment shows signs of effectiveness while continuing to monitor safety. More participants are enrolled than in Phase 1 to help refine the treatment protocol.

Is NCT05426044 currently recruiting?

Yes, NCT05426044 is actively recruiting participants. Contact the research team at cleung21@hku.hk for enrollment information.

Where is the NCT05426044 trial being conducted?

This trial is being conducted at Wong Chuk Hang, Hong Kong.

Who is sponsoring the NCT05426044 clinical trial?

NCT05426044 is sponsored by Christopher Kai Shun Leung. The principal investigator is Christopher LEUNG, MD at The University of Hong Kong. The trial plans to enroll 125 participants.

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