COVID-19 vaccines – the post-pandemic fight continues

COVID-19 vaccines – the post-pandemic fight continues

Moderna proves it’s still in the running as a major player in the mRNA vaccine IP landscape after the European Patent Office (EPO) maintains the validity of one of its key patents. 

Litigation around Europe and in the United States 

Back in 2022, Moderna alleged that Pfizer and German partner BioNTech copied it’s mRNA COVID-19 vaccine Spikevax® in order to manufacture their own mRNA COVID-19 vaccine Comirnaty®. As a result, Moderna brought infringement proceedings against Pfizer and BioNTech for two of its “crown jewel” patents EP3,718,565 (“EP’565”) and EP3,590,949 (“EP’949”) in the UK, Germany, Ireland, Belgium and the Netherlands. Pfizer and BioNTech consider both patents to be invalid. Parallel litigation is also taking place in the United States at the time of writing. 



This patent relates to an mRNA vaccine against a betacoronavirus that is formulated in a specific type of lipid nanoparticle. After grant of the patent in 2022, oppositions were filed by 4 opponents: BioNTech, Sanofi, Pfizer, and an anonymous opponent. The Opposition Division of the EPO revoked the patent on 7 December 2023 after concluding the claims added matter. Moderna is appealing the decision (T0201/21) at the time of writing, which has delayed the pending litigation around Europe. 

The outcome in the first instance proceedings for the other patent, EP’949, was more favourable for Moderna. 



This patent (claim 3 as granted) relates to an mRNA wherein the uracil nucleotides are replaced with N1-methyl-pseudouridine (m1Ψ). Substituting uracil with m1Ψ has the effect of reducing immunogenicity of the resulting mRNA when introduced into the host to improve vaccine efficacy and safety. 

After grant of the patent in 2022, a total of 9 oppositions were filed against the patent, including those by Pfizer and BioNTech, and also by Sanofi and GSK, which highlights the commercial importance of the patent. 

On 16 May 2024, the Opposition Division of the EPO held that EP’949 would be maintained in amended form (limited to claim 3 as granted), and we currently await the substantive written decision setting out their reasons. Given the importance of the patent, it is expected Pfizer and BioNTech will appeal the decision once issued1

Unlike EP’565, which specifically relates to COVID-19 vaccines, EP’949 relates more generally to modified mRNA and therefore has the potential to cover a broader range of mRNA vaccines. As reported in our previous articles here and here, we expect that patents directed to fundamental aspects of mRNA technology, such as mRNA modification, have the potential to shape the mRNA vaccine landscape. 


End of the saga? Quite the opposite! 

Following the decision by the Opposition Division of the EPO on EP’949, infringement proceedings that have previously been suspended in the national courts in Germany and Ireland2 can now resume (pending any filed appeals). 

In the meantime, the national courts in Germany, the Netherlands and Ireland3 have postponed hearing the cases on infringement whilst opposition appeal proceedings are pending on EP’565 at the EPO. 

Interestingly, there is already disagreement on the decision on validity of the two patents across Europe. For example, the District Court of The Hague held on 6 December 2023 that the Dutch part of EP’949 is invalid due to a lack of novelty4. Moderna is appealing the decision at the time of writing. 

Currently pending cases before the UK courts5 include a technical trial on infringement and, interestingly, the legal effect of a “pledge” made by Moderna in 2020 to not enforce their “COVID-19 related patents against those making vaccines intended to combat the pandemic”6. Moderna updated the “pledge” in 2022 to indicate that it “expects those using Moderna-patented technologies will respect the Company’s intellectual property” in more developed countries7. Pfizer and BioNTech question whether Moderna’s 2022 update to the “pledge” had legal effect since it wasn’t until 2023 when the WHO declared the pandemic over8. It will be interesting to see whether the other courts in Europe follow the UK decision once issued which will establish new case law relating to patent pledges. 

Meanwhile. in the United States, ligation before the United States District Court for the District of Massachusetts is currently stayed pending conclusion of an inter pares review of US 10,702,600 and 10,933,127 (family members of EP’565) before the Patent Trial and Appeal Board (PTAB) of the US Patent and Trademark Office. 

Despite falling sales of COVID-19 vaccines9,10,11, with some companies such as AstraZeneca beginning to withdraw related products12, it appears the global legal battle is far from over. Many, including us, will watch with bated breath as the decisions on validity and infringement of the above patents are handed down by courts and tribunals around the world. Such decisions have the potential to shape the research and development of a new generation of mRNA vaccines, including those targeted at Respiratory Syncytial Virus (RSV). The complex patent landscape of mRNA vaccines must therefore be navigated carefully, particularly from a freedom to operate (FTO) point of view. 

Our team has considerable experience advising clients on patent matters in relation to technologies such as mRNA vaccines, RNA interference (RNAi), antisense oligonucleotides, non-coding RNA (ASO), CRISPR-based genome editing and LNP chemistry. 

If you have a question relating to these technologies, please get in touch with one of our RNA experts: Andrea Hadfield, Beth Ormrod, James Cochrane, Jamie Atkins, Jessica Duncombe,Juliette Howarth, Oliver Lam, Samuel Bailey,Sarah Lau and Tom Leonard. 


5 HP-2022-000022 and HP-2022-000027

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