Early Conversion to Aflibercept for Persistent Diabetic Macular Edema Results in Better Visual Outcomes and Lower Treatment Costs

Patient adherence to therapy after switch to aflibercept from bevacizumab or ranibizumab for treatment-refractory neovascular age-related macular degeneration

PURPOSE

Clinical trials have demonstrated that switching patients from intravitreal bevacizumab (IVB) or ranibizumab (IVR) to aflibercept (IVA) for treatment-refractory neovascular age-related macular degeneration (nAMD) can decrease the injection frequency. This study evaluated whether there was a difference in the rate of injections or nonadherent events after switching therapies.

METHODS

The study comprised a retrospective, cross-sectional analysis of patients treated for nAMD from 2010 to 2018 who received ≥3 intravitreal injections of IVB/IVR prior to switching to IVA because of treatment-refractory nAMD. The treatment index, outcomes, and adherence to treatment were compared between both treatment regimens.

RESULTS

Sixty-two patients (67 eyes) met inclusion criteria. There was no change in the treatment index (0.65 versus 0.66, P = 0.650) or the number of nonadherent events (33 versus 36, P = 0.760) after the switch from IVB/IVR to IVA. Central macular thickness (CMT) increased 7.7%±13.8% in eyes that had a nonadherent event (283±69 µm to 304±75 µm after resuming care, P = 0.039). There was no short-term impact on visual acuity (VA) for this subset of eyes (0.387±0.202 LogMAR versus 0.365±0.156 LogMAR, P = 0.636). Patients who had nonadherent events ended the study with similar VA compared with patients who had no treatment lapses (0.370±0.616 LogMAR versus 0.337±0.638 LogMAR, P = 0.843).

CONCLUSION

Switching from IVB/ IVR to IVA for treatment-refractory nAMD in a real-world setting does not reduce the treatment index or increase adherence to treatment. Although there were short-term anatomical effects resulting from missed treatments, VA remained stable.

Persistent diabetic macular edema: Definition, incidence, biomarkers, and treatment methods

Intravitreal antivascular endothelial growth factor (anti-VEGF) treatment has drastically improved the visual and anatomical outcomes in patients with diabetic macular edema (DME); however, success is not always guaranteed, and a proportion of these eyes demonstrate persistent DME (pDME) despite intensive treatment. While standardized criteria to define these treatment-resistant eyes have not yet been established, many studies refer to eyes with no clinical response or an unsatisfactory partial response as having pDME. A patient is considered to have pDME if the retinal thickness improves less than 10-25% after 6 months of treatment. A range of treatment options have been recommended for eyes with pDME, including switching anti-VEGF agents, using corticosteroids and/or antioxidant drugs in adjunct with anti-VEGF therapy, and vitrectomy. In addition, multimodal imaging of DME eyes may be advantageous in predicting the responsiveness to treatment; this is beneficial when initiating alternative therapies. We explore the literature on persistent DME regarding its defining criteria, incidence, the baseline biological markers that may be useful in anticipating the response to treatment, and the available treatment options.

Retrospective analysis of the efficacy of early switching from bevacizumab to aflibercept or ranibizumab in diabetic macular edema

PURPOSE

The study aimed to compare the anatomical and functional gains of switching to ranibizumab or aflibercept in eyes with treatment-naive diabetic macular edema (DME) which has an inadequate response to three consecutive bevacizumab injections.

METHODS

This observational, retrospective, comparative study presented 12-month results of 80 patients with DME. One eye of each patient was enrolled, and bevacizumab was switched as aflibercept (40 eyes) or ranibizumab (40 eyes). DME was diagnosed based on a fundoscopic examination, fundus fluorescein angiography (FFA), central macular thickness (CMT), and best-corrected visual acuity (BCVA).

RESULTS

Forty-one patients (51.2%) were male, and 39 (48.8%) were female, with a mean age of 62.3 ± 6.7 years. At the end of the study, the mean number of intravitreal injections was 8.1 ± 1.8 in the aflibercept group, whereas 8.9 ± 1.4 in the ranibizumab (p = 0.091). The mean CMT decreased from 449.2 ± 69.3 µm to 311.0 ± 48.9 µm in the aflibercept group, and from 444.9 ± 109.2 µm to 316.3 ± 54.5 µm in the ranibizumab group (for both, p < 0.0001). The mean BVCA increased from 49.2 ± 11.1 ETDRS letters to 62.5 ± 9.9 in the aflibercept group (p < 0.0001) and from 49.9 ± 12.0 ETDRS letters to 61.1 ± 9.1 in the ranibizumab group (p < 0.0001). Macular laser treatment was required in 17.5% of the aflibercept group and 22.5% of the ranibizumab group (p = 0.781).

CONCLUSION

Significant improvement was observed with ranibizumab and aflibercept treatments in initial bevacizumab-resistant DME. Early switching therapy may contribute to better visual and anatomical outcomes.

Optical Coherence Tomography Angiography Biomarkers Predict Anatomical Response to Bevacizumab in Diabetic Macular Edema

PURPOSE

To identify biomarkers that may predict an early anatomical response to the treatment of diabetic macular edema (DME) with intravitreal bevacizumab (IVB) by means of optical coherence tomography angiography (OCTA).

METHODS

This study is a retrospective study of treatment-naïve patients with DME who underwent 6 × 6 mm OCTA imaging of the macula at baseline and after three monthly IVB injections. Thirty-six eyes of 23 patients were included. Eyes that demonstrated evidence of an early anatomical response, consisting of a >10% decrease in central macular thickness (CMT) (n = 18), were compared with those eyes that failed to show such an improvement (n = 18).

RESULTS

At baseline, early-response eyes had worse starting best-corrected visual acuity (BCVA, LogMAR 0.84 ± 0.41 versus LogMAR 0.51 ± 0.15, p = 0.004) and a larger CMT (490 ± 135 µm versus 356 ± 33 µm, p = 0.001), but smaller foveal avascular zones (FAZ) (0.309 ± 0.098mm versus 0.413 ± 0.095 mm, p = 0.003) compared with eyes that proved refractory to three monthly injections of IVB. The vascular density (VD) in both the foveal superficial and deep capillary plexuses was significantly greater in eyes that showed an early-treatment response compared with eyes that were non-responders (24.86 ± 6.90% versus 19.98 ± 7.13%, p = 0.045 and 32.30 ± 4.88% versus 26.95 ± 7.25%, p = 0.028, respectively). Early-treatment response to IVB was predicted by starting CMT (r ²= 0.266, p = 0.001), FAZ size (r ²= 0.234, p = 0.003), and VD in the superficial parafovea (r ²= 0.217, p = 0.004) and deep fovea (r ²= 0.157, p = 0.037).

CONCLUSION

Projection-resolved OCTA may be useful in predicting an early anatomical response of DME to treatment with IVB.