Anti-VEGF injections alone or with laser for severe diabetic macular swelling

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults with type 1 or type 2 diabetes who had severe swelling at the centre of the retina (diabetic macular oedema). After eye injections of anti-VEGF, the swelling is still there, but the retina is now thinner than 400 microns.

Age

Over 18 years

Sex

All sexes can join

Disease stage

Severe diabetic macular oedema at first (central retina thickness 400 μm or more), still present within the first year of anti-VEGF treatment, with central retina thickness now below 400 μm.

Earlier treatment

Must be within the first year of starting anti-VEGF treatment. Cannot have had anti-VEGF before the severe diabetic macular oedema was first found. Earlier macular laser for this swelling is allowed.

Biomarker or test result

Central retina thickness (CRT) below 400 μm at randomisation; it was 400 μm or more when first diagnosed.

Main reasons for not taking part

• Macular swelling caused by something other than diabetes
• Active proliferative diabetic retinopathy (treated and inactive is allowed)
• Unlicensed anti-VEGF drugs such as bevacizumab
• Pioglitazone that cannot be stopped for the whole trial
• Cataract surgery or pan-retinal laser within the last 6 weeks

The registry criteria, word for word

What the trial wants to find out

The macula is the centre of the retina; it gives central sight, colour and fine detail. People with diabetes may develop diabetic macular oedema (DMO). In DMO, fluid leaks from blood vessels and builds up at the macula, causing sight loss. DMO can be mild or severe; this is determined by measuring, in microns (µm), how thick the macula is. One µm is one-thousandth of a millimetre. People presenting with mild DMO (macula less than 400 µm thick; normally it is around 250 µm but varies with sex and ethnicity) are offered macular laser treatment. Laser works well for these patients. Subthreshold micropulse laser (SML), which does not damage the macula, works as well as standard laser, which produces a burn, and is cost-effective. However, many people present with severe DMO (macula 400 µm or thicker) where the laser does not work well. The standard treatment is eye injections of anti-VEGFs. VEGF stands for vascular endothelial growth factor. VEGF is high in eyes with DMO and causes blood vessel leakage. Anti-VEGFs block VEGF. They are given monthly to begin with, then every 2-3 months for months or years until DMO clears. In many patients DMO comes back after clearing and anti-VEGFs need to be re-started most often monthly initially again. To improve the care of people with severe DMO this study will compare the current standard care (anti-VEGFs alone) with a strategy in which patients begin with an anti-VEGF but switch to SML once the macula is less than 400 µm thick.

The 2 groups in the trial

• Subthreshold Micropulse Laser (SML)Existing treatment, for comparison
• Anti-VEGF Monotherapy (standard care)Existing treatment, for comparison