Abstract
Purpose :
To investigate changes in vitreous inflammatory and angiogenic cytokine levels following intravitreal injection of FAc implant in patients with diabetic macula edema (DME). The primary endpoint was the change in IL-6.
Methods :
A single center (Frankfurt University) investigator initiated phase IV study involving 12 patients eyes with DME, suitable for the FAc implant treatment. Vitreous fluid samples were obtained (partial vitrectomy =pPPP) prior to intravitreal injection of the FAc implant; pPPV and sampling were repeated after 1 and 6 months and material examined using a cytometric bead array to measure IL-6, IL-8, IP-10, MCP-1, VEGF and CD54 and an enzyme-linked immunosorbent assay to measure PIGF. Changes in the cytokine and chemokine expression patterns were analyzed with Friedman’s and Kolmogoroff-Smirnoff-Tests. The study is BfArM approved: EudraCT-Number: 2016-004488-38.
Results :
Cytokines respond differently to the primary procedure. There was a significant reduction for IL6, IP10, MCP-1, CD54 and PIGF (p < 0.05), following the administration of a FAc implant, VEGF and IL8 had a reduced mean expression with more variability in reaction to FAc (VEGF p = 0.6, IL8 p = 0.36). All of these had a significant impact on the decrease of central retinal thickness (OCT) and on reduction of intraretinal bleedings and exudates in fundus photography (p < 0.05), vision could be stabilized (p = 0.8).
Regarding the impact of therapy to the presence of proliferative (PDR) versus non-proliferative diabetic retinopathy (NPDR), the levels of IL6 and IL8 (p < 0.05) were significantly higher in PDR patients at baseline and clearly distinguish for CD54 and PIGF (p < 0.1). The difference was not significant for IP 10, MCP-1 and VEGF (p > 0.1). The decrease of all parameters was numerically greater in the PDR versus NPDR group. Nethertheless, for all parameters except MCP-1, the values at month 12 stayed numerically lower in the NPDR group versus the PDR group.
Conclusions :
This is the first data about changes in vitreous inflammatory and angiogenic cytokine levels following intravitreal injection of the FAc implant in patients with DME. Data showing reduced expression were maintained 6 months after administration of a single FAc implant, also leading to improved clinical parameters.
This is a 2020 ARVO Annual Meeting abstract.