Effect of IOP Lowering on Progressive HM (PHM)

Effect of Medically Intraocular Pressure Lowering on Progressive High Myopia

Currently, whether and when intraocular pressure (IOP) lowering medication should be used in progressive high myopia (HM) to control axial elongation is still a dilemma. Randomized trials are required to evaluate whether IOP lowering influences the growth of axial length in progressive HM eyes.

Study Overview

• Status: Active, not recruiting
• Conditions: Intraocular Pressure; High Myopia
• Intervention / Treatment: Drug: Assigned Interventions: IOP-lowering eye drops

Detailed Description

Myopia has emerged as a major health issue in east Asia, especially the sight-threatening complications associated with high myopia (HM). Complication of HM can be associated with significant ocular morbidities including maculopathy, retinal detachment, and glaucoma.

Previous studies have shown that adult patients with HM have sustained growth of the axial length (AL), which is a risk factor for the progression of pathological myopia and thus may further affect the visual function , so how to slow down the sustained growth of the AL in adult patients with HM has become an urgent clinical problem. Previous studies have shown that IOP-lowering treatment is a protective factor for the growth of the AL in HM , and the results of animal experiments have further shown that medically IOP-lowering treatment can significantly slow down the AL lengthening and refractive changes in the guinea pig model of myopia. On this basis, the investigators proposed in a previous article that medically IOP-lowering treatment may slow down the growth of AL by three pathways related to the sclera and choroid: for the sclera, IOP-lowering treatment may reduce the scleral distending force, slow down the rate of scleral distension, and inhibit the activation of scleral fibroblasts to reduce scleral remodeling; for the choroid, IOP-lowering treatment may increase choroidal blood perfusion and for the choroid, hypotensive treatment can increase choroidal perfusion and thus reduce scleral remodeling due to scleral hypoxia. A previous retrospective study conducted by the investigators also shows that medically IOP-lowering treatment could control the progression of AL in HM, but there is still a lack of evidence from relevant robust randomized controlled clinical trials (RCT).

The investigators propose to conduct a RCT to evaluate whether medically IOP-lowering therapy is effective in controlling the progression of AL in HM. Secondly, this study also aims to provide data to evaluate IOP-lowering treatment effects on the incidence of changes in the visual field (VF), optic nerve head morphology including the retinal nerve fiber layer (RNFL), and retinal ganglion cell-inner plexiform layer (GC-IPL) loss, progression of myopic maculopathy, loss in visual function and change in quality of life. The outcomes of this study may provide a strong basis for treatment recommendations to control the progression of high myopic eyes, and to provide high-quality clinical research evidence for international clinical guidelines on myopia.

• Study Type: Interventional
• Enrollment (Estimated): 152
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510060
      • Zhongshan Ophthalmic Center, Sun Yat-sen University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Informed consent given, and consent form signed.
2. Age between 18 and 65 years.
3. Diagnosed with HM: spherical equivalent ≤ -6.00 diopters or AL ≥ 26.5 mm.
4. Progressive HM: progression in AL ≥0.05mm in the past 6 months or ≥0.1mm in the past 12 months.
5. IOP ≥ 10 mmHg and ≤ 21mmHg on at least 2 visits, as measured by Goldmann applanation tonometry .
6. Best corrected visual acuity (BCVA) ≥ 6/12, and being able to obtain adequate AL examination, fundus photographs, optical coherence tomography (OCT) and complete the VF examination.

Exclusion Criteria:

1. Allergic to any kind of IOP-lowering therapy.
2. Combination of various serious fundus pathologies, such as proliferative diabetic retinopathy, retinal detachment, central retinal artery occlusion, etc.
3. Combination of chronic, recurrent or severe ocular inflammatory lesions, such as chronic or recurrent uveitis.
4. Patients with significant corneal or iris lesions, or severe cataract affecting fundus examination, or patients with only one eye.
5. Patients who have undergone any surgery or laser treatment affecting eye parameters during the follow-up period (within the last 1 year), such as cataract surgery.
6. Patients with other serious systemic diseases, such as hypertension, heart disease, diabetes, rheumatic immune system disease, etc., who cannot tolerate long-term follow-up and eye treatment.
7. Pregnant or lactating women, or those who plan to have children during the follow-up period.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention arm; medical reduction of IOP by eyedrops	Drug: Assigned Interventions: IOP-lowering eye drops; IOP-lowering eye drops Xalacom eyedrops (combination drops, fixed latanoprost with timolol) will be the choice for treatment.
No Intervention: control arm; follow up without medication

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
progression of axial length (AL)	The number of subjects whose AL progressed during the follow up	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of visual field (VF) defects or progression	The number of subjects whose VF defects progressed during the follow up	12 months
Incidence of changes in the optic nerve head morphology including the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL)	The number of subjects whose optic nerve head morphology including the RNFL and GCIPL changed during the follow up	12 months
progression of myopic maculopathy	The number of subjects whose myopic maculopathy progressed during the follow up	12 months

Collaborators and Investigators

• Sponsor: Sun Yat-sen University
• Investigators: Principal Investigator: Xiulan Zhang, MD, PhD, Sun Yat-sen University

Publications and helpful links

General Publications

• Leske MC, Heijl A, Hyman L, Bengtsson B. Early Manifest Glaucoma Trial: design and baseline data. Ophthalmology. 1999 Nov;106(11):2144-53. doi: 10.1016/s0161-6420(99)90497-9.
• Leske MC, Hyman L, Hussein M, Heijl A, Bengtsson B. Comparison of glaucomatous progression between untreated patients with normal-tension glaucoma and patients with therapeutically reduced intraocular pressures. The effectiveness of intraocular pressure reduction in the treatment of normal-tension glaucoma. Am J Ophthalmol. 1999 May;127(5):625-6. No abstract available.
• Garway-Heath DF, Crabb DP, Bunce C, Lascaratos G, Amalfitano F, Anand N, Azuara-Blanco A, Bourne RR, Broadway DC, Cunliffe IA, Diamond JP, Fraser SG, Ho TA, Martin KR, McNaught AI, Negi A, Patel K, Russell RA, Shah A, Spry PG, Suzuki K, White ET, Wormald RP, Xing W, Zeyen TG. Latanoprost for open-angle glaucoma (UKGTS): a randomised, multicentre, placebo-controlled trial. Lancet. 2015 Apr 4;385(9975):1295-304. doi: 10.1016/S0140-6736(14)62111-5. Epub 2014 Dec 19.
• Jiang J, Lin T, Lin F, Kong K, Wang P, Song Y, Zhou F, Wang Z, Jin L, Liu Y, Gao X, Chen J, Chen M, Lam DSC, Jonas JB, Chen S, Zhang X; Glaucoma Suspects with High Myopia Study Group. Effect of intraocular pressure reduction on progressive high myopia (PHM study): study protocol of a randomised controlled trial. BMJ Open. 2024 Jun 5;14(6):e084068. doi: 10.1136/bmjopen-2024-084068.

Helpful Links

• Related Info

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2023
• Primary Completion (Estimated): November 20, 2026
• Study Completion (Estimated): November 30, 2028

Study Registration Dates

• First Submitted: April 13, 2023
• First Submitted That Met QC Criteria: April 29, 2023
• First Posted (Actual): May 9, 2023

Study Record Updates

• Last Update Posted (Actual): May 27, 2026
• Last Update Submitted That Met QC Criteria: May 21, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: intraocular pressure; high myopia
• Additional Relevant MeSH Terms: Eye Diseases; Refractive Errors; Myopia; Pharmaceutical Solutions; Ophthalmic Solutions
• Other Study ID Numbers: 2023KYPJ110

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No