AstraZeneca AB v. Mylan Pharms. Inc.

Case Name: AstraZeneca AB v. Mylan Pharms. Inc., No. 1:18CV193, 2021 WL 798856 (N.D.W.V. Mar. 2, 2021) (Keeley, J.) 

Drug Product and Patent(s)-in-Suit: Symbicort® (budesonide and formoterol fumarate dihydrate); U.S. Patents Nos. No. 7,759,328 (“the ’328 patent”), 8,143,239 (“the ’239 patent”), and 8,575,137 (“the ’137 patent”)

Nature of the Case and Issue(s) Presented: The patents-in-suit cover Symbicort, a drug indicated to treat asthma in patients six years and older, and as a maintenance treatment in patients with chronic obstructive pulmonary disease. The patents claim a new formulation to deliver the steroid budesonide and a bronchodilator called formoterol fumarate dehydrate. Mylan filed an ANDA for a generic version of Symbicort prior to the expiration of the patents-in-suit. Astrazeneca sued Mylan. The parties stipulated that Mylan’s generic products infringed the patents-in-suit, leaving the issue of validity under 35 U.S.C. § 103 for the court to resolve. The court found that Mylan failed to demonstrate by clear and convincing evidence that the asserted claims of the patents-in-suit were invalid for obviousness.

Why AstraZeneca Prevailed: The court found that a skilled artisan “would not have been motivated to select the specific formulation claimed by the patents-in-suit” at the time of the priority because “it is unclear what would have prompted (or even enabled)” a skilled artisan as of the priority date to select and combine all the elements of the claimed invention. Even though there was a large amount of prior art that suggested a formulation with all of the claim components at issue, the “unpredictable ways each adjustment [of the prior art] could impact the overall formulation created an insurmountable hurdle” for the skilled artisan. This included wide varieties in the available active ingredients, the choice to use the specifically claimed propellant, and the choice to use particular excipients in specific concentrations. The court found that Mylan’s arguments amounted to “simply experimenting in the ‘design space’, and did not consider how different amounts of various ingredients could impact each other” given the fact that the number of combinations disclosed by one piece of prior art alone was in the millions.

Moreover, the court pointed to expert testimony, which found that in one instance the prior art actually taught away from the claimed formulation, as a POSA would have understood that the claimed formulations would be unstable due to the combinations closest to the claimed formulation leaving a residue at the gas-liquid exchange barrier. As such, the court held that “without clues pointing to the most promising combinations, an artisan could have spent years experimenting without success … [and Mylan’s] proposed routine optimization would not have resulted in the claimed invention within a reasonable period of time.”