Intravitreal Macugen for Ischaemic Diabetic Macular Oedema

• Status: Completed
• Trial end date: 2013-03-01
• Target enrollment: 0
• Participant gender: All

Summary

Diabetic macular oedema (DME) is one of the leading causes of blindness in the United Kingdom's working population. It affects the macula, which lies at the centre of the retina, at the back of the eye. Damage to the macula can occur either because the blood supply is reduced (ischaemic DME), or because the blood vessels are leaking excessively (exudative DME).

A chemical called vascular endothelial growth factor (VEGF) may underlie some of the abnormalities seen in DME. Studies have shown that VEGF encourages leakage of fluid from blood vessels and increases the stickiness of white blood cells. When white blood cells are sticky they can attach to blood vessel walls. This may cause small blood vessels to block, and lead to ischaemia.

Laser treatment often helps to stabilise exudative DME, but there is currently no recognised treatment for ischaemic DME. Macugen (pegaptanib), a drug that inactivates VEGF, has been tried and found to be of benefit in treating exudative DME. Since VEGF promotes ischaemia, it is possible that Macugen will also prove to be beneficial for ischaemic DME. This has not been tested before.

A healthy macula is essential for good vision. The innermost area of the macula, the foveal avascular zone (FAZ), is the most important part. The FAZ is enlarged when it is ischaemic. This is a pilot study to assess whether Macugen can reduce the size of the FAZ in ischaemic DME. The investigators will also assess whether it can reduce retinal thickness and improve vision in ischaemic DME. Thirty patients will be involved in the study for thirty weeks each. They will have their eyes examined and receive an injection of Macugen into the eye every 6 weeks. The study is taking place in the Oxford Eye Hospital and is being funded by Pfizer, the company that makes Macugen.

• Phase: Phase 4
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: University of Oxford
• Collaborator: Pfizer

Criteria

Inclusion Criteria:

• Participant is willing and able to give informed consent for participation in the study.

• Male or Female, aged 18 years or above.

• DME

• BCVA 20/32 to 20/320 inclusive

• Central OCT thickness > 300 microns

• Enlargement of FAZ (ischaemia or capillary drop out of >30% on FFA)

• Female participants of child bearing potential must be willing to ensure that they or their partner use effective contraception during the study and for 3 months thereafter

• Able (in the Investigator's opinion) and willing to comply with all study requirements e.g. attending for tests and treatment every 6 weeks.

• Willing to allow his or her General Practitioner and consultant, if appropriate, to be notified of participation in the study.

Exclusion Criteria:

• Any co-existing ocular disease (with the exception of cataract)

• Female participants who are pregnant, lactating or planning pregnancy during the course of the study

• Any significant disease or disorder, e.g. recent stroke or myocardial infarction, which, in the opinion of the Investigator, may either put the participants at risk because of participation in the study, or may influence the result of the study, or the participant's ability to participate in the study

• Significant renal impairment, i.e. creatinine clearance < 20mL/min

• Participants who have participated in another research study involving an investigational product in the past 12 weeks

• Laser within 3 months

• Intraocular surgery within 6 months

• Known allergy to pegaptanib (Macugen [TM])

• Known allergy to fluorescein