Ranibizumab: new drug. Macular degeneration: second-line use due to risks

(1) Due to a lack of any better alternatives, photodynamic therapy is the standard treatment for subfoveal lesions due to neovascular age-related macular degeneration (AMD). It consists of intravenous injection of a photosensitizer, verteporfin, followed by local red laser activation. This treatment, sometimes repeated every 3 months, stabilises the loss of visual acuity for 2 years in about 50% of patients. Adverse effects are generally acceptable. (2) Ranibizumab is an antibody fragment targeting vascular endothelial growth factor (VEGF). VEGF is implicated in the neovascularisation involved in age-related macular degeneration. Ranibizumab is injected into the vitreous in the same way as pegaptanib, the first VEGF antagonist to be approved for an ocular indication. (3) Clinical evaluation of ranibizumab includes 2 placebo-controlled trials (900 patients in total), a trial versus verteporfin (423 patients), and a trial testing ranibizumab in combination with verteporfin (162 patients). More than 90% of patients treated with ranibizumab in these two trials had no tangible loss of vision for one to two years, compared to about 68% of patients treated with verteporfin (statistically significant difference). These trials did not attempt to determine the optimal interval between intravitreal injections. (4) No trials have directly compared ranibizumab with pegaptanib; indirect comparisons suggest that ranibizumab is better than pegaptanib. (5) Intravitreal injection of ranibizumab can have local adverse effects, similar to pegaptanib. These include inflammatory reactions, infections, and elevated intraocular pressure. Arterial thromboses at distant sites, in particular strokes, have been reported with ranibizumab, at a higher frequency with 0.5 mg per infection (about 1%) than with 0.3 mg per injection. (6) When visual acuity continues to deteriorate in patients with age-related macular degeneration despite treatment with verteporfin, ranibizumab provides an effective alternative for patients with no particular risk factors for stroke.