Inhibition of proliferative vitreoretinopathy by a newly developed methotrexate loaded drug carrier in vitro.

PURPOSE: Repeated intravitreal injections of methotrexate for proliferative vitreoretinopathy, a rare ocular condition that can cause vision loss, have shown beneficial effects in recent clinical studies. The purpose of this study was to develop a slow-release, long-term drug carrier composed of the polymer polylactide-co-glycolide and methotrexate that can be injected intravitreally. METHODS: The required composition of the drug carrier was modeled using pharmacokinetic parameters based on current literature. Release kinetics were determined using an ocular pharmacokinetic model. Epiretinal PVR-membranes were harvested during pars plana vitrectomy and subsequently transferred to cell culture. The effect of the drug carrier on cell migration was investigated using time-lapse microscopy and a scratch-induced migration assay. The colorimetric WST-1-assay and a live-dead-assay were performed to determine viability, and the BrdU-assay was applied for proliferation. RESULTS: The release profile showed an initial and a final burst of methotrexate with an intervening steady state that lasted 9-11 weeks. It showed inhibitory effects on pathobiological processes in human PVR-cells in vitro. Cell velocity in the time-lapse assay, migration in the scratch assay (p = 0.001), and proliferation in the BrdU assay (p = 0.027) were reduced after addition of the drug carrier. These effects occurred without causing a reduction in viability in the WST-1 assay (p > 0.99) and the live-dead assay. CONCLUSION: The methotrexate-loaded drug carrier can maintain a stable concentration for 9-11 weeks and influence the pathobiological process of PVR cells in vitro. Therefore, it represents a potential therapeutic orphan drug for PVR.

LONG-TERM EFFICACY OF FLUOCINOLONE IN EYES WITH IRIS-LENS DIAPHRAGM DISRUPTION AND PCME WITH MEDICATION FIXED IN THE SCLERA (MEFISTO).

PURPOSE: The aim of our prospective off-label, interventional clinical trial was to evaluate the efficacy and safety of the fluocinolone-loop-anchoring technique over two years in eyes with iris-lens diaphragm disruption and pseudophakic cystoid macular edema. METHODS: In 10 eyes, scleral fixation of fluocinolone implant was performed. Main outcome measures were the development of best-corrected visual acuity (BCVA), central retinal thickness over 24 months, and general safety of the procedure. RESULTS: A significant improvement to 0.57 ± 0.38 log MAR (Snellen 20/80) (range 0-1.30) was observed (P = 0.003) at 1 month. Further improvement to 0.45 ± 036 log MAR (Snellen 20/60) was observed until month 18 (P = 0.081). Mean central retinal thickness decreased by 22% from 601.6 ± 235.5 µm to 449.1 ± 128.9 µm at 1 month. In one patient, the implant has to be removed at Month 7 because of elevated intraocular pressure and one patient after globe rupture had a retinal redetachment at Month 4. CONCLUSION: In this study, we showed that the treatment of recalcitrant pseudophakic cystoid macular edema with scleral fixated fluocinolone implant in eyes with disruption of the iris-lens diaphragm provides good anatomical and functional results with a reasonable safety profile over 24 months in eyes where pseudophakic cystoid macular edema is otherwise difficult to treat and often left untreated.