This study will recruit 58 participants in a double-masked, multi-centre, sham-controlled clinical trial. Participants will receive Iluvien implantation or sham implantation (masked) with a concomitant intravitreal injection of ranibizumab at baseline with an allocation ratio of 1:1. This is followed by regular monthly clinic review and repeat intravitreal ranibizumab injections to the study eye according to a PRN (pro re nata) treatment protocol.
This trial aims to evaluate whether Iluvien implantation in addition to standard anti-VEGF injection treatment for diabetic macular oedema in pseudophakic eyes will show similar visual acuity outcomes but with an improved reduction in CRT (Central Retinal Thickness) while reducing the average number of intravitreal injections during the first 2 years of treatment, due to the continual micro-dosing of Iluvien therapy.
Participants meeting all the eligibility criteria will be randomized to either Iluvien implant or sham implant procedure with an allocation ratio of 1:1. Participants assigned to either treatment arms will receive intravitreal injection of ranibizumab after Iluvien implantation or sham implantation at the same baseline visit.
To maintain double-masking, participants assigned to the control arm will receive sham implantation. This will be performed with an empty Luer Lock Syringe without a needle attached to it, that will not penetrate the eye nor deliver any drug. Patients assigned to either treatment arm will receive ranibizumab intravitreal injection to the study eye at baseline 30 minutes after the Iluvien or sham implantation. The sham injection should be performed by the unmasked investigator. The unmasked investigator should not be involved in any patient assessment in the study.
Participants will be followed up monthly for 2 years. Participants from both arms will receive compulsory Ranibizumab injection during the first three monthly visit and followed by monthly Ranibizumab as per PRN protocol. The end of study visit should take place at 104 weeks from the baseline visit.
Visual acuity measurement should be performed by trial certified optometrist according to the standard ETDRS (Early Treatment of Diabetic Retinopathy Study) protocol. This is to be conducted in certified examination rooms.
Spectral domain OCT (Optical Coherence Tomography) should be used to assess diabetic macular oedema and optic disc morphology at each visit. The OCT viewer software should be able to provide objective retinal thickness measurement of the central 1mm subfield thickness. Technicians should check for segmentation errors with every OCT scan and make appropriate manual adjustments.
OCT machines and designated technicians at each site will be certified prior to study commencement. Patients must always be assessed using the same OCT model.
7-View Fundus Photography and Fluorescein Angiography (FA) will be performed at the screening visit to confirm the diagnosis of diabetic macular oedema and assess diabetic retinopathy.
Additional FAs may be undertaken during subsequent visits should the investigator believe that there is a clinical need for it. Investigators at each local site are responsible for FA and OCT image interpretation. There will be no centralized image reading centre involved in this study.
IOP (Intraocular Pressure) measurement should be performed with Goldman tonometry either with undilated or dilated pupils.
The primary outcome analysis will be performed to test the differences in the average number of intravitreal injections between the two treatment arms up to month 24. This will be carried out according to an intent to treat principle.
The change of visual acuity from baseline to month 24 will be tested for non-inferiority against the control arm. We will analyze the stability of visual acuity and CRT using AUC (Area Under Curve) Analysis and estimate the average cost of resources utilization for both treatment arms.
Methods of dealing with missing data will follow established techniques, using multiple imputation to impute missing data. If necessary sensitivity analyses will be undertaken to examine the dependence of the results on the method of imputation.
