Recovery of plasma vascular endothelial growth factor concentrations during aflibercept loading phase and after the transition to bimonthly treatment for neovascular age-related macular degeneration.

AIMS

To provide data on plasma vascular endothelial growth factor (VEGF) concentration during three consecutive monthly intravitreal aflibercept injections and after transition to bimonthly treatment in patients with neovascular age-related macular degeneration (nAMD).

METHODS

Sixteen consecutive treatment-naïve Caucasian patients with nAMD were included in the study. The treatment consisted of one intravitreal aflibercept (2 mg) injection every 28 days for three consecutive months followed by a fourth injection 8 weeks later. VEGF plasma concentrations were measured with Luminex on day 0 (baseline, prior to first injection); days 1, 6 and 27 (prior to second injection); day 55 (prior to third injection) and days 97 and 111 (after third injection).

RESULTS

Baseline plasma VEGF concentration was 59.6±13.3 pg/mL. Aflibercept decreased plasma VEGF concentration to 32.5±3 pg/mL on day 1 (p<0.0001) and 34.7±6.3 pg/mL on day 6 (p<0.0001). On day 27, the VEGF plasma level increased to 50.6±6.5 pg/mL (p=0.009) and on day 55 to 52.8±8.8 pg/mL (p=0.027). There was no statistically significant difference between mean plasma VEGF concentrations on days 27 and 55 (p=0.139). Plasma VEGF concentration recovered completely 6 weeks after the third injection, reaching 57.9±9.6 pg/mL on day 97 (p=0.600) and 59.5±11.6 pg/mL on day 111 (p=0.987).

CONCLUSIONS

Intravitreal aflibercept decreases plasma VEGF concentration mostly in the first week after treatment. Despite repeated monthly intravitreal injections, there was a monthly increase in plasma VEGF values to near baseline levels, with complete recovery 6 weeks after the third injection.

TRIAL REGISTRATION NUMBER

Identifier no. NCT02125864.