Bevasiranib, the first small interfering RNA agent developed for the treatment of neovascular age-related macular degeneration, has demonstrated clinical promise. Injected intravitreally, this small interfering RNA acts by inducing catalytic destruction of messenger RNA to silence gene expression. Bevasiranib targets the production of vascular endothelial growth factor (VEGF) protein. It does not affect existing VEGF protein, suggesting that it may offer a synergistic effect when given in combination with anti–VEGF treatments, such as ranibizumab. The safety of bevasiranib has been supported by preclinical and clinical research.