Sanofi Sues Moderna and Pfizer Over Vaccine Patents
French pharmaceutical giant Sanofi has launched a new wave of high-stakes patent litigation against Moderna and Pfizer, alleging that the companies’ blockbuster COVID-19 vaccines—and, in Moderna’s case, its respiratory syncytial virus (RSV) vaccine—unlawfully use Sanofi-owned messenger RNA (mRNA) delivery technology without authorization. The lawsuits, filed in the U.S. District Court for the District of New Jersey, seek patent royalties rather than an injunction blocking vaccine sales, further intensifying the years-long legal battle over the valuable intellectual property behind mRNA vaccines.
Sanofi’s claims center on lipid nanoparticle (LNP) technology, a crucial component of mRNA vaccines. Lipid nanoparticles act as microscopic delivery vehicles that protect fragile mRNA molecules and transport them safely into human cells, allowing the vaccines to produce an immune response. According to the complaints, Moderna’s Spikevax, mNEXSPIKE, and mRESVIA vaccines, along with Pfizer and BioNTech’s Comirnaty COVID-19 vaccine, infringe multiple patents covering methods and compositions for mRNA delivery. Sanofi argues that these technologies are protected by patents owned by its subsidiary Translate Bio, which the company acquired in a $3.2 billion acquisition in 2021 to strengthen its mRNA research capabilities.
Unlike some patent disputes that seek to halt competing products, Sanofi has made clear that it is not attempting to remove the vaccines from the market. Instead, the company says it is seeking “fair compensation” through royalty payments for the alleged use of its patented technology. This approach reflects the continued public health importance of COVID-19 vaccines while recognizing the significant commercial value generated from products that have collectively earned tens of billions of dollars in global revenue since the pandemic.
The lawsuits further expand an increasingly complex web of litigation surrounding mRNA technology. Since the commercial success of COVID-19 vaccines, numerous pharmaceutical and biotechnology companies have sought compensation for intellectual property they claim contributed to vaccine development. Moderna has been involved in several major patent disputes, including its own infringement lawsuit against Pfizer and BioNTech filed in 2022. Earlier this year, Moderna also agreed to pay up to $2.25 billion to resolve patent infringement claims brought by Genevant Sciences and Arbutus Biopharma over separate lipid nanoparticle technology used in its COVID-19 vaccine.
Sanofi’s complaints allege that Moderna infringes 10 patents covering mRNA delivery innovations, while Pfizer’s Comirnaty vaccine allegedly infringes eight of those same patents. The company argues that the accused vaccines rely on lipid nanoparticle formulations that fall within the scope of Translate Bio’s patented inventions. Pfizer and Moderna had not publicly responded in detail to the allegations at the time the lawsuits were filed.
The litigation reflects the enormous commercial stakes associated with mRNA technology. The rapid development of COVID-19 vaccines transformed mRNA from an emerging scientific platform into one of the pharmaceutical industry’s most valuable technologies. Beyond COVID-19, drug manufacturers are investing heavily in mRNA-based vaccines and treatments targeting influenza, RSV, cancer, and rare diseases. As companies race to expand these products, ownership of foundational patents has become increasingly important, with successful patent holders potentially entitled to substantial royalty payments on future products.
Patent experts note that disputes involving pharmaceutical innovation often focus less on whether a product is effective and more on who owns the underlying inventions that made commercialization possible. Courts will likely examine whether the accused vaccines actually practice the patented methods, whether the patents are valid and enforceable, and whether alternative technologies were used instead. Because many of these patents involve sophisticated biotechnology, the litigation is expected to involve extensive scientific testimony and technical evidence.
The outcome of Sanofi’s lawsuits could have implications beyond the immediate parties. If Sanofi succeeds in establishing infringement, Moderna and Pfizer could be required to pay significant royalties while continuing to market their vaccines. Conversely, if the companies successfully defend the claims or invalidate the asserted patents, it could weaken Sanofi’s intellectual property position in the rapidly expanding mRNA field. The litigation also highlights how the pharmaceutical industry continues to transition from pandemic-driven vaccine development toward long-term competition over ownership of foundational biotechnology innovations.
Although the lawsuits focus on patent royalties rather than product availability, they underscore the growing importance of intellectual property in determining which companies ultimately benefit from one of the most transformative medical technologies of the past decade. As additional vaccine and therapeutic products enter the market, these legal battles are expected to shape licensing agreements, future research investments, and the commercialization of next-generation mRNA medicines.
Key Legal Outcome
- Sanofi filed separate federal patent infringement lawsuits against Moderna and Pfizer in the U.S. District Court for the District of New Jersey.
- The company alleges the vaccines infringe patents covering mRNA lipid nanoparticle (LNP) delivery technology acquired through its purchase of Translate Bio.
- Moderna is accused of infringing 10 patents through its COVID-19 and RSV vaccines, while Pfizer is accused of infringing eight patents through its COVID-19 vaccine.
- Sanofi is seeking patent royalties and financial compensation, not an injunction preventing vaccine sales.
- The lawsuits add to the growing network of global patent disputes involving mRNA vaccine technology.
Why It Matters
- The litigation could determine ownership rights over key mRNA delivery technology used in some of the world’s most successful vaccines.
- A ruling in Sanofi’s favor could result in substantial royalty payments from future vaccine sales.
- The case highlights the increasing importance of intellectual property in next-generation vaccine development.
- The outcome may influence future licensing agreements and innovation across the biotechnology industry.
- The decision could shape how courts interpret and enforce foundational mRNA technology patents in future pharmaceutical disputes.
