Regeneron Pharmaceuticals, Inc. and Sandoz have reached an agreement on a patent infringement dispute over Sandoz’s EYLEA biosimilar: Enzeevu (aflibercept-abzv).
Refresh me on Sandoz.
The Swiss company was originally established by Novartis in 2003 to specialize in developing—and commercializing—a portfolio of generic pharmaceuticals and biosimilars.
See here for details on these products (and the company’s 2022 spin-off from Novartis).
Now to Enzeevu.
The EYLEA biosimilar was approved by the FDA in August 2024 for wet age-related macular degeneration (AMD)—notably, just one of EYLEA’s several retinal disease indications.
- Details on this indication can be viewed here.
To note: While the dosage form, administration route, and presentation of Enzeevu are the same as EYLEA, its prescribing information includes a few additional notes.
Next up: this legal situation.
Just 2 weeks after Enzeevu was granted regulatory approval in the U.S., Regeneron filed a patent infringement lawsuit against Sandoz.
The company’s claim: Sandoz infringed—in other words: broke the terms of an agreement or law—46 of its patents (with some reportedly expiring as late as 2040) on its reference drug (Eylea). See pages 4 and 5 of the lawsuit to view these patents.
- Specifically, the company claimed that Sandoz violated the Biologics Price Competition and Innovation Act (BPCIA), which enables an expedited review process for biosimilars.
Tell me more about BPCIA.
This act creates a period of market exclusivity (12 years, to be exact) for reference products (such as EYLEA), during which no applications can be submitted until 4 years after the reference drug was first licensed.
- The intent behind this: To increase access to safe and effective biologics through competition—as well as lower drug prices.
But more importantly: BPCIA also mandates that biosimilar manufacturers (such as Sandoz) provide information to the reference drug’s company (Regeneron, in this case) that markets the reference product (Enzeevu).
And the issue Regeneron raised?
According to the company’s claim, Sandoz did not provide this information.
Other noncompliance Regeneron identified was a failure (on Sandoz’s part) to notify them within 20 days of submitting an abbreviated Biologics License Application (aBLA) for Enzeevu’s FDA approval—as required under BPCIA.
- Instead: Sandoz allegedly notified Regeneron of the FDA’s approval for its biosimilar on the same day the company issued a press release to the public.
As such: Regeneron referred to Sandoz’s aBLA submission as “an act of infringement,” that—per BPCIA guidelines—authorized Regeneron to file a lawsuit against the company.
Yikes. So what did the companies agree to with this settlement?
Following what Sandoz referred to as “months of vigorous defense” against Regeneron’s claims, the two rivals agreed to the following:
- Sandoz may enter the U.S. commercial market with Enzeevu in Q4 2026*
- *Potentially even earlier, in certain (undisclosed) circumstances
Anything else to keep in mind?
In announcing this agreement, Sandoz also reiterated that the FDA had provisionally determined Enzeevu would be interchangeable with EYLEA, “as it is currently subject to an unexpired exclusivity for the first interchangeable biosimilar products.”
What an “interchangeable” status means: Enzeevu has met additional requirements demonstrating it can be safely and effectively substituted for EYLEA (with the same clinical benefits and no additional side effects) without the need for consultation with a physician.
Lastly, any other EYLEA lawsuits to know about?
Regeneron is certainly no stranger to these (see here and here for the company’s victories over the years).
In fact, earlier this year, the company’s patent infringement lawsuit against Biocon Biologics was dismissed—paving the way for yet another biosimilar (YESAFILI) to launch in H2 2026.