Anti-VEGF Non-Responders are often short-term responders

Abstract

Purpose : The purpose of our study was to investigate the duration of anti-VEGF treatment effect in patients with neovascular age-related macular degeneration (nvAMD), diabetic macular edema (DME) and retinal vein occlusion, and to determine if non- or poor-responders at the standard 4-week interval actually demonstrate a treatment response at an earlier time point.

Methods : This study is a prospective multi-center trial with patients recruited from the Eye Clinic of the University Hospital of Heraklion and from the OMMA Eye Institute in Athens, Greece. Patients received intravitreal anti-VEGF (0.5 mg ranibizumab) injections and subsequently were assessed weekly for a total period of 4-6 weeks by spectral-domain optical coherence tomography (SD-OCT) for reduction in central retinal thickness (CRT) and the presence of intra- and subretinal fluid. Data collected included age, sex, visual acuity, past ocular history, total retinal volume, axial length and lens status.

Results : 52 eyes of 52 patients (mean age 67.8 years, 59.6% female, 54% treatment naive) were assessed. More than half of the eyes (51.5 %) presented with maximal CRT reduction on SD-OCT two-weeks post-injection and almost all had significantly increased CRT at week 4 compared to week 3 or week 2. Eyes that showed no to minimal CRT reduction at week 4 and would have been classified as non-responders in the usual clinical evaluation were found to have CRT reduction at weeks 2 or 3 post-injection. Furthermore, we found a higher proportion of non- and poor responders at week 4 in DME (7 of 12, 58%) compared to nvAMD (6 of 25, 24%) eyes (chi-square 4.194, p=0.0406). The time to maximal CRT reduction was not related to axial length, age, lens status or prior history of injections.

Conclusions : Our study suggests that almost all non-responders or poor responders to anti-VEGF therapy are responders if assessed at an earlier time point such as at week 2 or 3 post-injection. Our study assesses for anti-VEGF treatment response by weekly CRT measurements with SD-OCT and is the first study to describe the treatment response in previously considered non-responders. Further large, prospective studies are needed to optimize dosing intervals and to evaluate whether more frequent anti-VEGF treatment might preserve visual function in this cohort of short-term responders.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

Frequency histogram of time to maximal CRT reduction

 

Three example patients showing early CRT reduction followed by increase at week 4