Comparison of subconjunctival TRIamcinolone acetonide injection and intravitreal dexamethasone (OZurdex) injection for uveitic and postoperative macular oedema: the TRIOZ study

Aims To compare effectiveness of subconjunctival triamcinolone acetonide injections and intravitreal injections of dexamethasone 700 µg implants in reducing central macular thickness (CMT) in uveitic and postoperative macular oedema (ME). Methods We conducted an open-label, French multicentre randomised comparative trial with a logarithmic CMT non-inferiority margin set at 0.06. Patients were adults with non-infectious inflammatory ME, without any contraindication to the treatments. They were randomised 1:1 to receive either triamcinolone or dexamethasone. The primary endpoint was the difference in CMT among treated eyes between baseline and 2 months, measured with spectral-domain optical coherence tomography. Secondary outcomes included visual acuity, laser flare, vitreous haze, duration of action, tolerance to injections and adverse events. Results Between January 2016 and January 2020, 106 patients were enrolled (54 in the triamcinolone group and 52 in the dexamethasone group). Subconjunctival triamcinolone injections seemed to be non-inferior to intravitreal dexamethasone injections, especially at month 3 (and nearly at month 1). Nevertheless, we could not demonstrate it, with a treatment effect at month 2 of 0.05 (0.01 ; 0.09) (p value=0.001). This was corroborated by post hoc analyses in the postoperative subgroup, for whom the non-inferiority was nearly demonstrated at month 2 with a treatment effect of 0.02 (−0.03 ; 0.08) (p=0.37). There was no significant difference in the occurrence of adverse effects. Conclusion We could not demonstrate the non-inferiority of triamcinolone injections at month 2. Nevertheless, they showed some efficacity, particularly in treating postoperative ME, being as safe as dexamethasone injections, without any loss of chance if a therapeutic switch is necessary.