Serum Vascular Endothelial Growth Factor Levels in the IVAN Trial; Relationships with Drug, Dosing, and Systemic Serious Adverse Events

Ophthalmol Retina. 2018 Feb;2(2):118-127. doi: 10.1016/j.oret.2017.05.015.

Abstract

Purpose: To describe serum vascular endothelial growth factor (sVEGF) in patients with neovascular age-related macular degeneration (nAMD) receiving anti-VEGF agents and associations between sVEGF and systemic serious adverse events (SSAEs).

Design: Exploratory analyses of a randomized controlled trial that enrolled 610 participants with nAMD and compared 2 anti-VEGF antibodies, ranibizumab and bevacizumab, and 2 treatment regimens, monthly vs. discontinuous, with 2 years' follow-up.

Participants: Adults aged 50+ years with treatment-naïve nAMD and a visual acuity of ≥25 letters (Snellen equivalent 20/320) in the affected eye.

Methods: Intravitreal injection of anti-VEGF antibodies.

Main outcome measures: sVEGF and occurrence of SSAE, with particular interest in arteriothromboembolic events (ATE) and immunologically mediated events (IME).

Results: On average, sVEGF (measured at months 0, 1, 11, 12, 23, and 24) decreased from a geometric mean of 168 pg/mL at baseline to 64 pg/mL at month 24. The decrease was greater with bevacizumab than with ranibizumab and was dependent on time since last treatment; at month 24 sVEGF was 11% lower with bevacizumab if treated ≥3 months previously, 51% lower if treated 2 months previously, and 76% lower if treated the previous month, compared with ranibizumab. The hazard of experiencing an ATE increased with age (hazard ratio [HR] = 2.01; 95% confidence interval [CI] = 1.32-3.05; P = 0.001) and higher sVEGF (HR = 1.16; 95% CI = 1.03-1.30, per 100 unit rise in sVEGF; P = 0.013). There was no association between sVEGF and the hazard of an IME (HR = 1.01; 95% CI = 0.76-1.33; P = 0.942); however, the hazard of an IME was significantly increased by treatment with bevacizumab compared with ranibizumab (HR = 3.53; 95% CI = 1.35-9.22; P = 0.010). The hazard of an "other SSAE" (not categorized as ATE or IME) increased with age (HR 1.51, 95% CI 1.14-2.01, P = 0.005) and decreased if an injection had been administered within the previous month (HR = 0.68; 95% CI = 0.45-1.03; P = 0.069).

Conclusions: The decrease in sVEGF is greater with bevacizumab than with ranibizumab, but this difference is eliminated when treatment is withheld for 3 months. Higher sVEGF increased the hazard of an ATE and bevacizumab increases the hazard of an IME compared with ranibizumab.

Keywords: ATE, arteriothromboembolic event; CI, confidence interval; DVT, deep vein thrombosis; GMR, geometric mean ratio; HR, hazard ratio; IME, immunologically mediated event; RPE, retinal pigment epithelium; SSAE, systemic serious adverse event; VEGF, vascular endothelial growth factor; nAMD, neovascular age-related macular degeneration; pVEGF, plasma vascular endothelial growth factor; sVEGF, serum vascular endothelial growth factor.