Vilanterol / Umeclidinium – USA

 

On Nov. 19, 2020, Federal Circuit affirmed judgment of infringement & damages against Glaxo.

Plaintiff (Vectura Ltd) filed suit in 2016 against defendant (Glaxo) for alleged infringement of US 8,303,991 patent. The ’991 patent concerns the production of “composite active particles” for use in pulmonary administration, such as in dry-powder inhalers. The composite active particles described in the patent consist of additive material (magnesium stearate) that is adhered to particles of active ingredient. The additive particles promote the dispersion and delivery of the active ingredient into the lungs when the inhaler is activated. The specification discloses “milling method” to produce composite active particles.

In the district court, Vectura alleged infringement by GSK’s Ellipta-brand inhalers: the Breo, Anoro, and Incruse devices. Each of the accused inhalers features one or more “blisters,” which are sealed receptacles containing a single active ingredient, an excipient, and, optionally, additive material. The blisters use magnesium stearate as the additive material and lactose as the excipient. GSK uses multi-step mixing process. GSK first mixes the lactose excipient with magnesium stearate in the absence of the active ingredient. After a de-lumping step, GSK then mixes the lactose particles with the active ingredient. In that step, small particles of the active ingredient are deposited onto the larger lactose particles.

The issue here is claim construction of two disputed terms: 1) “composite active particles” and 2) “promotes the dispersion of the composite active particles”.

With respect to first claim construction, GSK’s proposed construction of that term included a process limitation requiring that the composite active particles be “formed by milling . . .But district court rejected that argument & construed the term to mean “[a] single particulate entit[y/ies] made up of a particle of active material to which one or more particles of additive material are fixed such that the active and additive particles do not separate in the airstream.”  During appeal Glaxo challenged the said construction & said that the court should have construed that term to require that the composite particles be produced by the “high energy milling” process referred to in the specification. GKS argued this based on support in the specification & based on prosecution history. During prosecution Vectura said that wet-mixing processes disclosed in prior art were different from the “aggressive milling procedure” recited in the application. For this reason, GSK argued, the applicants clearly disclaimed mixing processes other than high-energy milling, confirming that the term “composite active particles” should be construed to include a process limitation.

Federal Circuit, however, denied the arguments & said that although the ’991 patent contains a few statements suggesting that its high-energy milling is required, those statements are outweighed by the numerous statements indicating that high-energy milling is merely a preferred process. Moreover, the fact that the ’991 patent criticizes other methods is not dispositive. Therefore, the specification of the ’991 patent does not make its milling method an essential part of apparatus claim 1. With respect to prosecution response, Federal Circuit said that the statement did not purport to add a process limitation to the apparatus claim. Instead, that statement merely sought to demonstrate that Prior art’s coated particles were necessarily different from the applicants’ coated particles because it used a process that could not possibly produce “particulate additive matter on the surface of [a] particle of active material,” as required by the applicants’ claim. Applicant distinguished prior art based on the unique structure of the claimed composite particles, not the disclosed milling method.

With respect to second claim construction, Parties agreed that Vectura needed to prove that the use of magnesium stearate in the accused inhalers improves the dispersion of the active ingredient compared to identical products in which only the lactose excipient is coated with magnesium stearate. GSK argued that there was no substantial evidence of infringement as to that limitation because Vectura staked its case on a defective scientific test (referred to as “Study 2). Federal Circuit, however, said that the principal flaw in GSK’s argument is that Vectura did not rely solely on Study 2 to prove that the accused inhalers satisfy the dispersion limitation. Vectura introduced other evidence on dispersion as well. Vectura’s witnesses testified that coating active ingredient particles with magnesium stearate helps overcome the tendency of the particles to stick together and therefore increases the dispersion of the particles in the lungs. Evidence of tests conducted on coated and uncoated active-ingredient particles showed that coating the active particles substantially increased the dispersion of the active-ingredient particles and thus the amount of the active ingredient that could be delivered deep into the lungs. Tests run on GSK’s products showed that the particles of vilanterol and umeclidinium were consistently associated with magnesium stearate.

Federal Circuit thus affirmed the infringement & also damages awarded by the Jury.