Context: In March 2022, Alnylam sued Pfizer and BioNTech in the District of Delaware for allegedly infringing five patents covering the use of its lipid nanoparticles (LNP), which are used to deliver RNA-based therapeutics or vaccines into the body (March 17, 2022 complaint). Pfizer and BioNTech denied the allegations, arguing that the patents-in-suit were invalid. They then moved for summary judgment of non-infringement based on favorable claim construction. In a separate litigation filed by Ingenus Pharmaceuticals and Leiutis Pharmaceuticals LLP in February 2022, the plaintiffs sued Nexus Pharmaceuticals in the Northern District of Illinois for infringing a patent related to cyclophosphamide drug liquid formulations used in cancer disease treatment. In an opinion issued earlier this month, Judge Mary M. Rowland of the United States District Court for the Northern District of Illinois ruled that Ingenus could proceed alone in its dispute against Nexus, while Leiutis was dismissed from the case for lack of standing (May 6, 2025 opinion).
What’s new: Alnylam has withdrawn its opposition to Pfizer and BioNTech’s motion for summary judgment, after an opinion by Judge Colm Connolly of the United States District Court for the District of Delaware interpreted the company’s patents in a way that would not cover Pfizer and BioNTech’s vaccine (May 13, 2025 unopposed motion to stay (PDF)). Meanwhile, Nexus has successfully obtained a summary judgment of patent invalidity against Ingenus, terminating the case in the district court (May 9, 2025 order).
Direct impact and wider ramifications: In Alnylam’s case against Pfizer and BioNTech, the court will soon issue a final judgment of non-infringement. A statement by the company yesterday said Alnylam may appeal that judgment, however. And, if that is upheld, the proceedings would resume based on the patentee’s preferred claim construction. In the other case, while Nexus’s win in the Northern District of Illinois means the dispute comes to an end for now, Ingenus’s option to appeal is still on the table.
The patents-in-suit in Alnylam v. Pfizer, BioNTech, all entitled “Biodegradable lipids for the delivery of active agents”, included:
- U.S. Patent No. 11,246,933
- U.S. Patent No. 11,590,229
- U.S. Patent No. 11,612,657
- U.S. Patent No. 11,633,479
- U.S. Patent No. 11,633,480
Now that Alnylam has withdrawn its opposition to the defendants’ motion for summary judgment, the court will soon issue a final judgment of non-infringement. This judgment will be based on a claim construction that Alnylam disagreed with, however, and in a statement yesterday, a spokesperson for Alnylam said the company may appeal.
Alnylam presumably chose to withdraw its opposition as it would have delayed proceedings, incurring further costs. This move allowed the plaintiff to concede non-infringement based on the district court’s claim construction.
If the Federal Circuit affirms the claim construction on appeal, then Alnylam’s case is over.
However, if it proceeds, and the Federal Circuit reverses the district court’s claim construction, then the final judgment will be vacated.
BioNTech said today that Alnylam’s decision “confirms Pfizer’s and BioNTech’s position that [they] do not infringe any valid patents asserted by Alnylam.”
This is not the first time that Alnylam has suffered a defeat over its COVID vaccine patents. In a parallel dispute against Moderna last year, the company agreed to dismiss the case without prejudice after a Delaware federal court ruled in favour of the defendant, issuing a judgment of non-infringement (October 2, 2024 Reuters article).
The patent-in-suit in Ingenus Pharmaceuticals v Nexus Pharmaceuticals was:
- U.S. Patent No. 10,993,952 (“Stable ready to use cyclophosphamide liquid formulations”)
In her summary judgment of invalidity last week, Judge Rowland held all claims of the patent as indefinite. The judge ruled that the claim term “stable” was not properly defined. She added:
“Nexus has established by clear and convincing evidence that an impermissible ‘zone of uncertainty’ exists.”
Counsel
Alnylam Pharmaceuticals was represented by McDermott Will & Emery LLP’s William G. Gaede III, Anisa Noorassa, Sarah Chapin Columbia, Sarah J. Fischer, Ian B. Brooks, Timothy Dunker, Bhanu K. Sadasivan, Mandy H. Kim, and Ethan H. Townsend.
Pfizer was represented by Connolly Gallagher LLP’s Arthur G. Connolly, III and Alan R. Silverstein, as well as Willkie Farr & Gallagher’s Sara Tonnies Horton, and Daniel Constantinescu.
BioNTech was represented by Morris, Nichols, Arsht & Tunnell LLP’s Anthony David Raucci, Jack B. Blumenfeld, Jeremy A. Tigan, as well as Winston & Strawn LLP’s Charles B. Klein, Jovial Wong, Claire A. Fundakowski, Brian L. O’Gara, and Ashley Graham.
Ingenus Pharmaceuticals was represented by Green Griffith & Borg Breen LLP and Sughrue Mion PLLC.
Nexus Pharmaceuticals was represented by ArentFox Schiff’s Imron Aly, Sal Patel, Joel Wallace, and Kevin Nelson.
Global COVID patent infringement litigation
Pfizer and BioNTech’s case is one of an increasing number of COVID vaccine-related patent infringement disputes around the world. In October, Pfizer celebrated a major win in a dispute against CureVac, when the High Court of Justice for England & Wales (EWHC) invalidated two of the latter’s patents. GlaxoSmithKline also joined the mRNA patent wars last April, suing Pfizer and BioNTech for infringing five of its COVID-19 vaccine patents (April 26, 2024 ip fray article). That dispute was concluded within 12 months, however, after GSK and Pfizer announced last month that they would be dismissing their case with prejudice (April 4, 2025 ip fray article).
Moderna’s Spikevax has also been targeted in several patent infringement suits. In February 2022, nucleic acid delivery company Genevant Sciences and clinical-stage biopharmaceutical company Arbutus Biopharma Corporation sued Moderna for allegedly infringing six U.S. patents in the District of Delaware (February 28, 2022 Genevant press release). The companies then expanded their enforcement campaign in March, filing suits in the Federal Court of Canada, the Tokyo District Court, Switzerland’s Federal Patent Court, and the Unified Patent Court (UPC) (March 4, 2025 ip fray article). Genevant and Arbutus are seeking monetary relief and injunctions against Moderna’s infringing vaccinations in every jurisdiction.
The company was also sued by GlaxoSmithKline and Northwestern University in parallel actions in the District of Delaware last year (October 17, 2024 ip fray article).
Moderna did gain some ground in its global dispute against Pfizer last year, though, including when the European Patent Office upheld the validity of one of its key patents in May, and the EWHC issued a landmark judgment finding Pfizer was infringing one of Moderna’s patents with its COVID-19 vaccine Comirnaty. That decision was the first time a company was found to have its COVID-19 vaccine infringe a valid patent.
mRNA litigation is also on the rise in China, where the Supreme People’s Court last December announced the settlement of a major osteoarthritis drug dispute between Zhen Medical and Rui Biotech (December 13, 2024 ip fray article). That settlement also involved a licensing agreement granting Rui Biotech access to Zhen Medical’s mRNA technology patent.