Real world evidence of use of anti-VEGF therapy in Denmark
Objective: This study evaluates real-world evidence regarding the frequency of anti-vascular-endothelial-growth-factor (VEGF) injections during the first year of therapy of treatment-naïve patients with neovascular age-related macular degeneration (nAMD), diabetic macular edema (DME) and retinal vein occlusion (RVO) from the Danish National Patient Registry. There was a switch in anti-VEGF treatment for naïve nAMD patients during the study period, following the introduction of aflibercept, which was expected to reduce the injection frequency relative to ranibizumab due to a perception of prolonged treatment duration of aflibercept.
Methods: All treatment-naïve nAMD, DME or RVO patients who received an intravitreal injection in Denmark from 1 January 2012 to 31 July 2015 were eligible for inclusion. Patients were required to have been treated for at least one year and, for nAMD, to have received at least three injections during the first four months of treatment. Patients were allocated to half-year groupings (2012/1 to 2014/1) based on registration of their first intravitreal injection. Injection frequency during the first year of treatment was calculated for each group and t-tests investigated whether injection frequencies changed over time.
Results: In treatment naïve nAMD patients (n = 500), the mean (SD) number of anti-VEGF injections increased significantly from 6.04 (1.71) in 2012/1 to 6.73 (1.62) in 2014/1 (p = .001; 2012/1 and 2012/2 vs. 2014/1) across all treatments. A similar trend was found for DME patients (n = 76) from 2012/1 to 2014/1 and RVO patients (n = 82) from 2012/2 to 2014/1, with mean injection frequencies increasing significantly from 5.14 (2.29) to 5.93 (1.98) (p = .007), and from 4.83 (1.21) to 6.08 (1.55) (p = .024), respectively. Post hoc sensitivity analysis also found a significant increase in injection frequency in nAMD patients who did not receive a loading phase (4.55 in 2012/1 and 5.05 in 2014/1; p = .006; n = 616).
Conclusions: In contrast to the decrease in injection frequency predicted with a switch to aflibercept treatment for nAMD, our study showed that injection frequencies increased significantly from 2012 to 2014 in patients initiating therapy across the three diseases.
