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.