Current approaches to the management of diabetic macular edema

Three modalities have a role in the primary management of diabetic macular edema (DME): laser photocoagulation, intravitreal vascular endothelial growth factor (VEGF) inhibitors, and intravitreal corticosteroid implants. Intravitreal VEGF inhibitors are most commonly used for center-involved DME, but laser photocoagulation and intravitreal corticosteroids also have an important role in DME management. Until recently, the selection of a VEGF inhibitor for a patient was complicated by a lack of comparative data and a much lower cost for bevacizumab compared with other agents. Two-year results of the landmark head-to-head Protocol T trial will inform treatment selection for ophthalmologists and formulary decisions for managed care organizations. The study found that patients with better baseline visual acuity benefited from aflibercept, bevacizumab, or ranibizumab. However, aflibercept and ranibizumab were more effective than bevacizumab for patients with worse baseline visual acuity. A higher rate of nonfatal stroke and vascular death with ranibizumab in the Protocol T trial has raised concern in the community and needs to be investigated further. Emerging drugs for DME include VEGF inhibitors with less-frequent dosing intervals, and new agents that target other pathologic processes that contribute to vascular leakage and angiogenesis in DME.