• Retina/Vitreous

    Previous studies have shown that 5-fluorouracil (5-FU) and low molecular weight heparin (LMWH), also known as dalteparin, could effectively prevent and treat proliferative vitreoretinopathy (PVR) following primary retinal detachment surgery. This study focuses on using the treatment for patients who have a high risk for developing PVR.

    Study design

    In this randomized, double-blind, controlled, multicenter, interventional trial, eligible patients had rhegmatogenous retinal detachments (RRD) for less than 4 weeks and laser flare meter readings ≥ 15.0 photon counts/milliseconds (pc/ms). Patients were excluded if they had trauma, giant retinal tears, visual pre-existing PVR grade C, and chronic inflammatory conditions in the study eye. Patients were randomized 1:1 to receive intravitreal verum (200 mg/ml 5-FU and 5 IU/ml dalteparin) or placebo (balanced salt solution) during vitrectomy to treat retinal detachment repair. The primary endpoint was the development of PVR grade CP (full-thickness retinal folds or subretinal strands in clock hours located posterior to equator) 1 or higher within 12 weeks after surgery, which was determined by grading of fundus photographs. Best-corrected visual acuity and re-detachment rate were secondary outcomes.

    Outcomes

    A total of 325 subjects were randomized (verum: n = 163; placebo: n = 162). The mean laser flare was 31 ± 26 pc/ms among all participants. No significant difference existed in the grade C PVR rate in the intention-to-treat analysis (verum: 28% vs. placebo: 23%), which included non-gradable images as failure. Likewise, no significant difference was found in the per-protocol analysis (verum: 12% vs. placebo: 12%), which only analyzed patients who had gradable images. No significant safety risks were identified in the treatment or placebo group.

    Limitations

    Based on the elevated flare measurements, there was a lower rate of Grade C PVR development in both groups compared to the expected rate, which may have limited the ability to detect a difference in the treatment and placebo groups.

    Clinical significance

    Verum (200 mg/ml 5-FU and 5 IU/ml dalteparin) is not effective at preventing Grade C PVR in patients with RRDs who are deemed high risk for developing PVR based on elevated flare measurements.