Ranibizumab

Ranibizumab is a humanized monoclonal antibody fragment (Fab) that binds vascular endothelial growth factor-A (VEGF-A). It is designed for intravitreal use to inhibit abnormal blood vessel growth and vascular leakage in the retina, thereby helping to treat several retinal diseases. The drug is marketed under the brand name Lucentis and was developed by Genentech, a subsidiary of Roche.

Indications and use include neovascular (wet) age-related macular degeneration (AMD), diabetic macular edema (DME), and macular edema following retinal vein occlusion (RVO). It has also been used for choroidal neovascularization associated with pathologic myopia. By blocking VEGF-A, ranibizumab reduces retinal edema and can stabilize or improve visual acuity in many patients.

Administration and dosing typically involve intravitreal injections. The standard regimen begins with monthly injections (0.5 mg) as an initial loading phase, followed by ongoing treatment at intervals determined by disease activity, commonly every 4 weeks, with options for as-needed or extended dosing in certain regimens.

Efficacy and safety outcomes vary by condition, but ranibizumab has been shown to improve or stabilize vision in many patients with wet AMD, and to reduce macular thickness and edema in DME and RVO-related conditions. Common ocular adverse events include conjunctival hemorrhage, eye pain, and intraocular inflammation, with rare but serious risks such as endophthalmitis and elevated intraocular pressure. Systemic exposure after intravitreal administration is low, but systemic thromboembolic events are monitored as a potential risk.

Pharmacokinetically, ranibizumab has a relatively short intravitreal half-life and is primarily cleared via local proteolysis.