Here's the reader question this primer answers: when a blockbuster biologic loses its core patent protection, what's left to defend? Regeneron's anti-VEGF eye franchise is a clean case study, and the patent record tells the story better than any earnings narrative.
Start with what the drug does. In diseases like wet age-related macular degeneration and diabetic retinopathy, the protein VEGF triggers leaky, abnormal blood vessels in the retina. Anti-VEGF drugs soak up VEGF so those vessels don't form. It works, it's a large market, and that success invites both biosimilar copies and direct competitors — which is exactly what the broader patent landscape shows.
The competitive field is crowded, and the grants prove it. Novartis holds US12649781B2 on treating diabetic retinopathy with its own anti-VEGF antibody, brolucizumab. Kodiak Sciences holds US12643958B2 on methods of treating eye disorders. These are not Regeneron patents — they are rivals with issued claims in the same indication. The "no orphan claims" rule applies here: every one of these is a specific, verifiable grant by a named competitor.
So how does an incumbent defend a maturing franchise? Regeneron's 2026 grant US12649031B2, "Methods for delivering agents with pre-filled syringes to minimize intraocular inflammation" (issued June 9, 2026), points to the answer: the device. A pre-filled syringe that reduces inflammation is a genuine clinical improvement and a fresh patent — one that a biosimilar of the molecule alone does not automatically inherit. The fight moves from the antibody to how the antibody gets into the eye.
This is a recurring pattern worth naming for the general reader. When the molecule's core protection erodes, defensible value migrates to the surrounding layers: formulation, dosing interval, and delivery hardware. A biosimilar can copy the active ingredient; it cannot necessarily copy a patented, inflammation-reducing injection system without infringing.
Read Regeneron's recent grants as a map of where the franchise is digging in. The core anti-VEGF idea is contested by Novartis, Kodiak, and biosimilar-makers. The newer Regeneron IP is increasingly about delivery and tolerability — the parts of the product a copycat can't simply replicate. That's the Eylea fight in one sentence: the molecule is commoditizing, so the company is patenting everything around it.