Federal Circuit Affirms Noninfringement in Actelion v. Mylan ANDA Case
The United States Court of Appeals for the Federal Circuit affirmed noninfringement for Mylan in Actelion v. Mylan on May 21, 2024.
Why it matters: This ruling reinforces how patent prosecution history and disclosures can restrict infringement claims against generics. Litigation and in-house teams must carefully draft and prosecute claims to preserve enforceable scope, especially in high-stakes pharma disputes.
- On May 21, 2024, the United States Court of Appeals for the Federal Circuit upheld a noninfringement verdict for Mylan.
- The ruling targeted patents for Actelion’s hypertension drug Veletri (epoprostenol), emphasizing limiting effects of prosecution history estoppel and the disclosure-dedication rule.
- Mylan filed its Abbreviated New Drug Application (ANDA) in February 2020; Actelion sued for patent infringement that June.
- The decision clarified that language left out of patent claims, but disclosed in the specification, may be dedicated to the public and not covered by the doctrine of equivalents.
The May 21, 2024 decision by the United States Court of Appeals for the Federal Circuit affirmed a district court's ruling that Mylan’s proposed generic version of Actelion’s Veletri did not infringe Actelion’s patents. The dispute centered on patents covering lyophilized epoprostenol formulations and involved complex Hatch-Waxman litigation between brand and generic manufacturers.
- Disclosure-dedication rule explained: The Federal Circuit underscored that a patent’s specification can dedicate subject matter to the public if it is disclosed but omitted from the claims. Here, certain excipients named in the specification but not claimed left Mylan’s generic outside Actelion’s patent scope.
- Prosecution history estoppel: The court reiterated that changing or narrowing claims during patent prosecution may prevent the patentee from later recapturing what was surrendered, foreclosing certain infringement arguments under the doctrine of equivalents.
- Actelion filed suit in June 2020 in the Northern District of West Virginia, arguing Mylan’s ANDA filing constituted infringement. The lower court granted summary judgment for Mylan, a result now affirmed on appeal.
Patent counsel should note the practical impact: claim language and amendments during prosecution play a pivotal role in future litigation. The Federal Circuit’s decision provides a cautionary tale for pharmaceutical patent owners seeking to assert formulation patents in generic drug cases.
By the numbers:
- May 21, 2024 — Date of Federal Circuit decision affirming noninfringement
- February 2020 — Mylan submitted its ANDA to the FDA
- June 2020 — Actelion initiated the infringement lawsuit
Yes, but: While clarifying patent doctrine boundaries, the decision does not close off all avenues for enforcement, especially where claim drafting is closely aligned with disclosed innovations.