Brolucizumab is a prescription medication used to treat specific eye conditions that can lead to vision loss. It is a type of biologic drug, meaning it is derived from living organisms. This medication works by targeting a particular protein in the body, helping to address the underlying causes of certain retinal diseases.
Conditions Brolucizumab Treats
Brolucizumab primarily treats neovascular (wet) age-related macular degeneration (AMD), a progressive eye disease that can cause severe vision impairment. In wet AMD, abnormal blood vessels grow underneath the macula, the central part of the retina responsible for sharp, detailed vision. These fragile vessels can leak fluid and blood, damaging the macula and distorting central vision.
The medication also treats diabetic macular edema (DME), a complication of diabetes that affects the eyes. DME occurs when high blood sugar levels damage blood vessels in the retina, causing them to leak fluid into the macula. This fluid buildup leads to swelling and blurred vision, making it difficult to perform daily tasks like reading or driving.
How Brolucizumab Works
Brolucizumab functions as an anti-vascular endothelial growth factor (VEGF) medication. VEGF is a protein that stimulates the growth of new blood vessels and increases the permeability of existing ones. In conditions like wet AMD and DME, an excess of VEGF contributes to the formation of leaky, abnormal blood vessels in the eye.
By binding to specific VEGF-A isoforms (VEGF110, VEGF121, and VEGF165), brolucizumab prevents them from interacting with their receptors, VEGFR-1 and VEGFR-2. This inhibition suppresses the proliferation of endothelial cells, which are the building blocks of blood vessels. As a result, the medication reduces the growth of new, unwanted blood vessels and decreases the leakage from existing ones, helping to stabilize vision and prevent further damage to the macula.
Administration and Potential Side Effects
Brolucizumab is administered as an intravitreal injection directly into the affected eye. A qualified clinician prepares and administers the drug. This method ensures the medication reaches the retina efficiently.
Patients receive the injection every 8 to 12 weeks, depending on the clinician’s assessment of disease activity. Following the injection, acute increases in intraocular pressure (IOP) can occur within 30 minutes, and sustained increases in IOP have also been reported, necessitating monitoring of eye pressure.
Potential side effects include ocular inflammation, such as iritis and uveitis, reported in a small percentage of patients. Other common ocular adverse events include eye pain, redness, and sensitivity to light. More serious, though less common, risks include endophthalmitis (an infection inside the eye) and retinal detachment, which are risks associated with any intravitreal injection.
There is also a risk of retinal vasculitis and retinal vascular occlusion, immune-mediated adverse events that can develop after the first injection. Patients experiencing intraocular inflammation should be closely monitored for these complications. Systemic side effects, such as arterial thromboembolic events (e.g., nonfatal stroke or heart attack), have been observed in a small percentage of patients receiving anti-VEGF therapies.