A study examined the effect of short-term aflibercept therapy on aqueous humor cytokine levels in treatment-naïve patients with center-involving diabetic macular edema (DME).
Treatment-naïve patients with DME with central subfield macular thickness at least 310 μm on optical coherence tomography between July 2015 and May 2017 were given three monthly intravitreal aflibercept injections. Aqueous samples for cytokine analysis were provided at baseline and after the final injection; multiplex immunoassay was used to measure various cytokines levels. The primary outcome was changes in aqueous cytokine levels from baseline to two months.
Seventeen patients with DME were enrolled in the study, of whom 16 completed it. Mean patient age was 57.2 years. At month two, compared with baseline, significant increases were observed in transforming growth factor-beta (TGF-β) 1 (P=0.004), TGF-β2 (P=0.017), inducible protein (IP)-10 (P=0.011), and hepatocyte growth factor (HGF; P=0.02). Significant reductions were observed in levels of vascular endothelial growth factor (VEGF; P<0.001), placental growth factor (PlGF; P=0.028), interleukin (IL)-6 (P=0.011), and platelet-derived growth factor-AA (PDGF-AA; P=0.003).
“In treatment-naive patients with DME, short-term aflibercept therapy not only results in VEGF and PlGF suppression, but also leads to reduced levels of IL-6 and PDGF-AA and higher concentrations of TGF-β1, TGF-β2, HGF, and IP-10,” the researchers concluded.