Patient adherence to therapy after switch to Aflibercept from Bevacizumab or Ranibizumab

Abstract

Purpose : Clinical trials have demonstrated that switching patients from intravitreal bevacizumab (IVB) or intravitreal ranibizumab (IVR) to intravitreal aflibercept (IVA) for treatment refractory neovascular age-related macular degeneration (nAMD) can decrease the frequency of injections. The present study was performed to determine if there was a difference in frequency of treatment and number of nonadherent events after switching patients to IVA.

Methods : The study comprised a retrospective, cross-sectional analysis of patients treated for nAMD from January 2010 to April 2018. Patients who received ≥3 intravitreal injections of IVB and/or IVR prior to treatment with ≥3 injections of IVA because of refractory nAMD were included. Treatment burden was calculated by dividing the number of possible injections at a maximal rate of one every four weeks by the actual number of injections received during each period of the study. A nonadherent event was defined as >14-day delay in follow-up beyond the recommended interval. Visual and anatomic outcomes were measured using best corrected vision and central macular thickness (CMT) determined by optical coherence tomography (OCT).

Results : Sixty-two patients (67 eyes) were identified for inclusion in the study. The switch from IVB/ IVR to IVA had no impact on the treatment burden (0.65 vs. 0.66, p=0.650) or the number of nonadherent events in each period (33 vs. 36, p=0.760). Risk of nonadherence was not associated with visual acuity (VA), CMT, age, gender, or distance from the clinic. CMT increased an average of 7.7±13.8% in eyes that experienced a nonadherent event (rising from 283±69 µm prior to 304±75 µm upon return to care, p=0.039). There was no short-term impact on VA for this subset of eyes (0.387±0.202 LogMAR vs. 0.365±0.156 LogMAR, p=0.636). Patients who had nonadherent events ended the study with similar VA compared with those who did not have gaps in treatment (0.370±0.616 LogMAR vs. 0.337±0.638 LogMAR, p=0.843). VA remained stable after switching to IVA for all study eyes (0.38±0.23 LogMAR at switch vs. 0.38±0.29 LogMAR at the end of study, p=0.900).

Conclusions : Switching from IVB/ IVR to IVA for treatment refractory nAMD does not significantly reduce treatment burden, nor increase adherence with treatment in a real-world clinical setting. Although there were short-term anatomical effects from missed treatments, VA remained stable.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.