Case Name: AstraZeneca AB v. Mylan Pharms., Inc., No. 2021-1729, 2021 WL 5816742 (Fed. Cir. Dec. 8, 2021) (Circuit Judges Taranto, Hughes, and Stoll presiding; Opinion by Stoll, J.; Opinion dissenting in part by Taranto, J.) (Appeal from N.D.W.V., Keeley, J.)
Drug Product and Patent(s)-in-Suit: Symbicort® (formoterol/budesonide); U.S. Patents Nos. 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 Symbicort inhaler—a pressurized, metered dose inhaler (“pMDI”)—was approved for the treatment of asthma and chronic obstructive pulmonary disease (“COPD”). The prior art included dry powder inhalers, which, as the name suggested, was a powder formulation requiring the patient to take a deep, fast breath. Dry powder inhalers had drawbacks, including the fact that they required children and elderly patients to take a deep breath to deliver the medication. Conversely, a pMDI was activated by pressing down on a button that caused propellant to disperse the medication as a spray. The asserted patent claims were directed to pharmaceutical compositions comprising formoterol fumerate dehydrate and budesonide.
Shortly before trial, the district court construed the term “0.001%” according to its “plain and ordinary meaning,” which meant one significant digit. Under that construction, Mylan stipulated to infringement. At trial, the district court concluded that Mylan had failed to demonstrate that the patents were invalid as obvious. Mylan appealed both the district court’s infringement and validity findings. The Federal Circuit vacated the judgement of infringement and remanded, and affirmed the determination of non-obviousness.
Why Mylan Prevailed: The parties agreed that “0.001%,” as an abstract number on a page, would encompass a range from 0.0005% to 0.0014%. Based on the written description, however, the Federal Circuit explained that it was “clear that the inventors understood that a formulation comprising 0.001% w/w PVP is more stable than (and indeed, different from) a formation with even a slight difference in the concentration of PVP, e.g., a formulation with 0.0005% w/w PVP.” In other words, the specification indicated that formulations with 0.001% w/w were intended to be more exact than as an abstract number. Further, during prosecution, to overcome an obviousness rejection for claims reciting “from about 0.0005 to about 0.05 %w/w,” the applicant narrowed the claim to 0.001% w/w PVP, explaining that this amount gave the best suspension stability. For those reasons, the Federal Circuit construed 0.001% as a “precise number, with only minor variations, i.e., 0.00095% to 0.00104%.”
Next, the Federal Circuit upheld the district court’s non-obviousness determination. Mylan argued that the district court incorrectly concluded that a prior-art reference, Rogueda, taught away from the claimed invention. When disclosing the Rogueda formulation, the prior-art reference also described certain control formulations that Mylan identified as allegedly rendering the claimed invention obvious. Rogueda conducted several experiments that compared its formulation to the control formulations that Mylan identified as the “prior art formulations.” But AstraZeneca’s expert testified that a skilled artisan, looking at Rogueda, would conclude that the control formulations “were not suitable” and clearly did not work. The Federal Circuit credited this testimony and found that the claimed invention was not invalid for obviousness.
Judge Taranto issued a separate opinion dissenting in part. Specifically, he would have concluded that “0.001%” should have its significant-figure meaning, i.e., the interval 0.0005% to 0.0014%. In support, Judge Taranto noted that the specification included six concentrations of PVP, including 0.0002%, 0.0005%, 0.001%, 0.01%, 0.03%, and 0.05% and noted that several of these formulations were “considered excellent.” As to the prosecution history, the dissent disagreed that AstraZeneca made a narrowing amendment as to the 0.001% claim limitation. The dissent also noted that Mylan’s proposed “minor variations” construction, without additional precision, actually added to the uncertainty of claim scope compared to the ordinary meaning. Stated another way, the phrase “minor variations,” without further construction to identify how much variations were permitted, effectively reinstated the “about” language that AstraZeneca removed in favor of the more precise “0.001%”.