Introduction

The case Teva Pharmaceutical Industries Ltd & Anor v Astellas Pharma Inc ([2023] EWCA Civ 880) before the England and Wales Court of Appeal (Civil Division) centered on a patent dispute concerning European Patent (UK) No 1 559 427, which claims the use of mirabegron for treating overactive bladder (OAB). The Appellants sought revocation of the patent and Supplementary Protection Certificate related thereto, arguing that the invention was obvious over prior art, specifically Australian Patent Application AU 199889288 ("288"). The Court of Appeal upheld the lower court's decision dismissing the Appellants' claims.

Summary of the Judgment

The High Court, led by Meade J, initially dismissed the Appellants' claim, determining that the Patent was not obvious in light of the prior art (288). The Appellants appealed, arguing that the judge erred in assessing obviousness and applying legal principles. The Court of Appeal upheld the original judgment, reaffirming that the Patent's disclosure of mirabegron as a selective ß3-AR agonist for OAB was not obvious based on the existing common general knowledge and prior patents. The Court emphasized the nuanced assessment of expert evidence and the specific technical contributions of the Patent.

Analysis

Precedents Cited

The judgment extensively referenced key cases that shape the current understanding of patent obviousness:

• Pozzoli SpA v BDMO SA [2007] EWCA Civ 588: Established a structured approach to assessing obviousness.
• Koninklijke Philips NV v Asustek Computer Inc [2019] EWCA Civ 2230: Reinforced the principles from Pozzoli regarding the assessment of obviousness.
• Conor Medsystems Inc v Angiotech Pharmaceuticals Inc [2008] UKHL 49: Discussed the concept of technical prejudice in patent law.

These precedents were pivotal in guiding the Court's analysis of whether the Patent's claims were obvious to a person skilled in the art.

Legal Reasoning

The Court employed a multi-factorial approach to assess obviousness, considering:

• Common General Knowledge (CGK): The judge evaluated what was commonly known in the field up to the priority date.
• Prior Art (288): Analyzed the Australian Patent Application to determine its relevance and teachings concerning ß3-AR agonists.
• Technical Contribution: Assessed whether the Patent provided a new and non-obvious technical solution, specifically the use of mirabegron for OAB.
• Expert Evidence: Evaluated the credibility and insights of expert testimonies from both parties.

The Court found that, despite some teaching in 288 regarding ß3-AR agonists, the specific application to OAB and the selection of mirabegron involved significant uncertainty and was not straightforwardly obvious. The Patent demonstrated a technical contribution by focusing on mirabegron with specific experimental results, albeit in rat models, which were deemed sufficient to establish non-obviousness.

Impact

This judgment reinforces the stringent standards for patent obviousness in the pharmaceutical sector, particularly concerning the selection and application of specific compounds for medical treatments. It underscores the importance of demonstrating a non-trivial technical contribution beyond existing knowledge and prior art. Future patent applications in similar domains will need to provide clear, specific advancements and address potential uncertainties in their claims to withstand challenges based on obviousness.

Complex Concepts Simplified

Common General Knowledge (CGK)

Definition: Information and understanding presumed to be widely known among professionals in a particular field at a specific point in time.

In this case, CGK included the understanding of ß3 adrenoreceptors and their role in treating OAB, as well as the limitations of existing ß3-AR agonists.

Obviousness in Patent Law

Definition: A patent claim is considered obvious if the invention would have been clear to a person skilled in the relevant field at the time of the invention, based on existing knowledge and prior art.

The core issue was whether using mirabegron, as disclosed in prior art, for treating OAB was an obvious step for a skilled professional.

Technical Prejudice

Definition: Preconceived notions or beliefs in the field that may discourage certain innovations or applications.

The Appellants argued that there was a technical prejudice against the efficacy of ß3-AR agonists for OAB, suggesting that overcoming this prejudice would render the Patent non-obvious. However, the Court found that the Patent sufficiently addressed these concerns.

Conclusion

The Court of Appeal's decision in Teva Pharmaceutical Industries Ltd & Anor v Astellas Pharma Inc reinforces the rigorous standards for establishing non-obviousness in pharmaceutical patents. By meticulously analyzing the common general knowledge, prior art, and the specific technical contributions of the Patent, the Court affirmed the validity of mirabegron's patent for treating overactive bladder. This judgment serves as a critical reference point for future patent disputes, emphasizing the necessity for clear, demonstrable advancements over existing knowledge to secure patent protection.