Introduction

The case of Actavis Group PTC EHF & Ors v. ICOS Corporation & Anor ([2019] UKSC 15) centers on the application of the inventive step, or obviousness, in the context of a pharmaceutical dosage patent under section 3 of the Patents Act 1977. The dispute involves a dosage patent held by ICOS, licensed to Eli Lilly, concerning the use of tadalafil for treating erectile dysfunction (ED). Generic drug manufacturers challenged the validity of this patent, arguing that the dosage regime claimed was obvious and lacked an inventive step.

This commentary delves into the intricacies of the judgment, exploring the legal principles applied, the precedents cited, the court’s reasoning, and the broader impact on patent law, particularly regarding dosage patents in the pharmaceutical industry.

Summary of the Judgment

The core issue in the case was whether the claimed dosage regime of tadalafil (ranging from 1mg to 5mg per day) for treating ED was obvious, thereby lacking an inventive step warranting patent protection. The Court of Appeal had previously invalidated the patent, asserting that the dosage claims were obvious based on prior art and routine clinical research processes.

The trial judge, Birss J, initially held that while a higher dose (25mg) was obvious, the lower dose of 5mg was not, citing unexpected benefits and value judgments required in identifying the minimal effective dose. However, the Court of Appeal reversed this decision, concluding that the overall research program to establish an appropriate dosage was routine and thus the lower dose did not involve an inventive step.

Ultimately, the Supreme Court dismissed the appeal, aligning with the Court of Appeal's reasoning that the dosage claims lacked an inventive step, rendering the patent invalid.

Analysis

Precedents Cited

The judgment references several key precedents that shaped the court’s approach:

• Windsurfing/Pozzoli Framework: A structured approach to assessing obviousness by identifying the skilled person, their knowledge, the inventive concept, differences from prior art, and whether these differences are obvious.
• Actavis UK Ltd v Merck & Co Inc [2009] EWCA Civ 444: Highlighted the standard practice of investigating dosage regimes and the general approach to dosage patents.
• Technograph Printed Circuits Ltd v Mills & Rockley (Electronics) Ltd [1972] RPC 346: Emphasized the prohibition of using hindsight in obviousness assessments.
• Generics (UK) Ltd v Lundbeck [2007] RPC 32: Discussed factors relevant to obviousness, including motive, multiple avenues, effort involved, and unexpected results.
• Conor Medsystems Inc v Angiotech Pharmaceuticals Inc [2008] UKHL 49: Reinforced the fact-specific, multi-factor approach to evaluating obviousness.

Legal Reasoning

The court meticulously applied the Windsurfing/Pozzoli structure to determine obviousness:

1. Notional Skilled Person: Defined as a clinical pharmacologist with experience in pharmacokinetics and a urology specialist.
2. Common General Knowledge: Included knowledge of PDE5 inhibitors like sildenafil, standard clinical trial phases, and dose-response relationships.
3. Inventive Concept: The specific dosage regime of 1mg to 5mg of tadalafil for treating ED.
4. Differences from Prior Art: The claimed dosage was lower than the known effective doses of sildenafil and tadalafil.
5. Obviousness Assessment: Determined whether, in light of prior art (Daugan patent) and common general knowledge, the dosage would have been obvious to test.

The court concluded that the process of determining an appropriate dosage was routine and within the expected scope of the skilled team's activities. While the 5mg dose yielded unexpected benefits, the court found that the overall research trajectory made the dosage regime obvious.

Impact

This judgment underscores the stringent requirements for an inventive step in dosage patents. It clarifies that routine clinical research processes, even if they yield unexpected benefits, may not suffice for patentability if the overarching research pathway is considered obvious. Pharmaceutical companies must demonstrate a non-obvious leap beyond standard research practices to secure patent protection for dosage regimes.

Complex Concepts Simplified

Conclusion

The Actavis Group v. ICOS Corporation judgment serves as a critical reference point for the assessment of inventive steps in pharmaceutical dosage patents. It reinforces the principle that while incremental improvements and routine research are essential to pharmaceutical development, they must transcend established practices to meet the inventive step criterion for patentability.

For practitioners and stakeholders in the pharmaceutical industry, this case highlights the importance of demonstrating a clear, non-obvious advancement in dosage regimes to secure patent protection. It also emphasizes the necessity of a fact-specific, multi-factor analysis in obviousness assessments, discouraging reliance on overly broad or mechanistic approaches.

Ultimately, the judgment balances the need to reward genuine innovation with the imperative to prevent monopolies on knowledge and practices that fall within the routine capabilities of skilled professionals.