Glaxo Group Ltd & Ors v Vectura Ltd

For patent claims requiring additive particles to be fused to, or smeared over, active particles, the relevant question is whether the process applies sufficient force to achieve that structural result. Milling need not reduce particle size and need not occur without carrier particles unless the claim requires it. Evidence that magnesium stearate is present near active particles does not establish structural fusion or a coating where the analytical method cannot reliably show the association. A patent is insufficient if it does not enable the skilled person to determine whether products or processes fall within the claims without undue effort. An Arrow declaration may be granted where it provides useful commercial certainty, particularly where infringement has failed for evidential reasons but the underlying process has been shown to be obvious.

Glaxo Group Ltd & Ors challenged the validity of five patents owned by Vectura Ltd and sought declarations concerning the obviousness of its dry powder inhaler processes and products.

Vectura alleged infringement by products containing vilanterol and umeclidinium. GSK denied infringement, sought revocation for obviousness and insufficiency, and relied on a Gillette defence. The principal issues were construction of claims requiring magnesium stearate to be fused to or form a coating on active particles, infringement, insufficiency, obviousness over Staniforth, Keller and Musa, and the discretionary grant of an Arrow declaration.

1. Construction. Composite active particles require the additive and active particles to be structurally combined so that they remain attached before, during and after actuation. “Fused”, “smeared over” and “coating” describe substantially the same concept. The claims did not require milling in the absence of carrier particles. Nor did the second alternative in the definition of milling require particle-size reduction. The relevant criterion was whether sufficient force or energy was applied to deform the additive and achieve the claimed fusion or coating (paras 125-137).
2. Infringement and insufficiency. The SEM and EDX evidence established the presence of magnesium stearate and its close association with active particles, but could not reliably establish contact, structural combination or fusion. The limitations of EDX and the absence of validation meant that infringement was not proved (paras 141-175). The same evidential problem meant that the skilled person could not determine whether processes or products fell within the claims without undue effort. The patents were therefore insufficient (paras 176-181).
3. Obviousness. Musa, Keller and Staniforth made it obvious to use high-shear blending, including when scaling up, and to apply the disclosed processes to different active ingredients. But GSK did not establish that following those disclosures would produce the claimed fused or coated composite particles. The patents were therefore not shown to be obvious over the cited prior art (paras 225-233). GSK’s own process and directly obtained products were nevertheless obvious over each item of prior art (paras 234-240).
4. Arrow declaration. Applying the principles in Fujifilm Kyowa Kirin Biologics Co Ltd v AbbVie Biotechnology Ltd and Generics (UK) Ltd v Yeda Research and Development Co Ltd, the court considered justice to both parties, useful purpose and special reasons. The unusual combination of evidential failure, non-invalidity findings and the limited undertaking justified relief. Declaration B accurately reflected the findings; Declaration A was too uncertain. Declaration B was granted and Declaration A refused (paras 241-258).