Severe diabetic macular oedema (DMO).
Comparator Arm: Anti-VEGF Monotherapy (standard care) Anti-VEGFs including ranibizumab and biosimilars, aflibercept, faricimab, and brolucizumab will be used, as per the standard of care at participating sites. The anti-VEGF should be administered in line with the summary of product characteristics (SmPC). Intervention Arm: Subthreshold Micropulse Laser (SML) SML will be applied in line with the DAME Guideline and follow the DAME participant pathway. Eligible participants who provide consent will be randomised 1:1 to receive SML or to continue with anti-VEGF monotherapy. A minimisation algorithm will be used to ensure balanced allocation of participants across trial arms for potentially important factors including centre, duration of DMO (≤1year, >1year), number of doses of anti-VEGFs received up to the time of randomisation (1-6; 7-12), type of anti-VEGF used (ranibizumab, ranibizumab-biosimilar, Brolucizumab, aflibercept, or faricimab) up to the time of randomisation, which will be continued throughout the trial unless lack of efficacy is observed and rescue treatment is needed, presenting BCVA [BCVA ≥ 69 ETDRS letters (Snellen equivalent ≥ 20/40; logMAR ≥ 0.3), 24–68 ETDRS letters (Snellen equivalent ≤20/50-20/320; logMAR 0.4–1.2) and CI-DMO (Yes, No). Minimising randomisation by these variables will ensure both trial arms will be balanced with regard to these potentially important baseline characteristics.
1. Adults (>18 years) 2. Diabetes type 1 or type 2 3. Presented with severe centre-involving (CI)-DMO (CRT ≥400 μm) 4. Within the first year of initiating anti-VEGF therapy but who still have DMO and their CRT is below 400 μm (and it remains, at the time of randomisation) following anti-VEGF therapy in either one eye or both eyes
1. Causes of macular oedema other than DMO 2. DMO with CRT ≥400 μm 3. Receipt of anti-VEGFs before their presentation with severe DMO (previous macular laser treatment for DMO is allowed) 4. Use of unlicensed anti-VEGFs (e.g. bevacizumab) 5. Inability, for any reason, to attend study visits 6. Active proliferative diabetic retinopathy (PDR) (treated and inactive PDR is allowed) 7. Use of pioglitazone which cannot be stopped for the duration of the trial 8. Cataract surgery or laser pan-retinal photocoagulation (PRP) within the previous 6 weeks 9. Currently enrolled in a CTIMP (Clinical Trial of an Investigational Medical Product) 10. Declined consent for participation