Altana Pharma AG v. Teva Pharmaceuticals USA, Inc.

566 F.3d 999, 91 U.S.P.Q. 2d (BNA) 1018, 2009 U.S. App. LEXIS 10262, 2009 WL 1332741
CourtCourt of Appeals for the Federal Circuit
DecidedMay 14, 2009
Docket19-2015
StatusPublished
Cited by82 cases

This text of 566 F.3d 999 (Altana Pharma AG v. Teva Pharmaceuticals USA, Inc.) is published on Counsel Stack Legal Research, covering Court of Appeals for the Federal Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Altana Pharma AG v. Teva Pharmaceuticals USA, Inc., 566 F.3d 999, 91 U.S.P.Q. 2d (BNA) 1018, 2009 U.S. App. LEXIS 10262, 2009 WL 1332741 (Fed. Cir. 2009).

Opinions

WARD, District Judge.

Plaintiffs-Appellants Altana Pharma AG and Wyeth (collectively, “Altana”) appeal the decision of the United States District Court for the District of New Jersey denying a preliminary injunction. Because the district court did not abuse its discretion, we affirm.

I. BACKGROUND

Appellants, Altana Pharma AG and Wyeth, accuse appellees, Teva Pharmaceuticals USA, Inc. (“Teva”), Sun Pharmaceutical Industries, Ltd. (“Sun”), et al. (collectively, “Defendants”) of infringing U.S. Patent No. 4,758,579 (“the '579 patent”). Wyeth is the exclusive licensee of the '579 patent in the United States. The '579 patent issued on February 9, 1988. On January 4, 2004, the U.S. Patent and Trademark Office (“USPTO”) granted a 5-year term extension pursuant to 35 U.S.C. § 156 (“the Hatch-Waxman Act”); thus, the '579 patent expires on July 19, 2010.

The '579 patent is directed to the compound pantoprazole, the active ingredient in Altana’s antiulcer drug Protonix ®. The compound pantoprazole belongs to a class of compounds known as proton pump inhibitors (“PPIs”) that are used to treat gastric acid disorders in the stomach. PPIs inhibit gastric acid secretion through their action on the gastric acid pump. When triggered by the body, the gastric acid pump is established in the secretory canaliculus of the stomach’s parietal cells via the enzyme H +, K +-ATPase. Once triggered, the pump transports protons, H +, from the inside of the parietal cell into the cell’s secretory canaliculus in exchange for potassium ions, K +, which the pump transports from the canaliculus to the inner portion of the cell. The availability of potassium ions within the canaliculus is attributable to the migration of potassium chloride, KCI, into the canaliculus, also from the inside of the parietal cell. As the pump reabsorbs the K+ in exchange for H + extrusion, the Cl' remains in the canaliculus, resulting in the formation of hydrochloric acid, HCI, within the canaliculus, which is then secreted into the stomach.

Although the operation of the gastric acid pump was known at the time of the invention at issue, the mechanism by which PPIs inhibit the gastric acid pump was not understood in the art until after the effective filing date of the '579 patent. Part of the uncertainty surrounding the method of action for PPIs is attributable to the fact [1003]*1003that PPIs are prodrugs, which are drugs that convert to their active form after they are delivered within a patient’s body, which typically exhibits a pH of about 5 to about 7. In this regard, PPIs are acid-activated prodrugs that are converted into their active form in the highly acidic environment, having a pH of about 1, within the secretory canaliculus of parietal cells. Once converted to its active form, the PPI thereafter binds to one or more cysteine amino acids in the acid pump. This binding inhibits the operation of the gastric acid pump.

The first commercialized PPI compound was omeprazole, which was approved for use by the U.S. Food and Drug Administration (“FDA”) in 1989 under the trade name Prilosec ®. Omeprazole was first synthesized by AB Hassle (now known as AstraZeneca) in 1979 and is the subject of U.S. Patent No. 4,255,431 (“the '431 patent”). Omeprazole or Prilosec ® is well known today as a blockbuster drug for the treatment of patients that suffer from heartburn, as well as other symptoms that stem from gastro-esophageal reflux disease (“GERD”). After the successful commercialization of Prilosec ®, many drug companies, including Byk Gulden (Altana’s predecessor), began to develop new PPIs to compete with omeprazole.

Altana’s research efforts resulted in the issuance of U.S. Patent No. 4,555,518 (“the '518 patent”) and the '579 patent. The application for the '518 patent was filed before the '579 patent, and contained a pharmacology section that compared the effectiveness of 18 claimed compounds against four prior art compounds. The '518 patent refers to one of the 18 compounds chosen for testing as compound 12. The '579 patent, which is not related to the '518 patent, claims PPI compounds that are structurally similar to the compounds claimed in the '518 patent. Pantoprazole, the compound at issue in this litigation, exhibits a structure that is very similar to compound 12 from the '518 patent.

There are three main structural elements to the PPI molecular backbone: the benzimidazole ring, the methylsulfinyl bridge, and the pyridine ring. The general formula of the PPI disclosed in the '579 patent is reproduced below:

[[Image here]]

'579 patent at 2:5-15. The issues in this case primarily relate to the pyridine ring (the right-most structure on the above compound), specifically, the radicals located on the pyridine ring (indicated by R2, R3, and R4). The '579 patent teaches that “R3 represents a l-3C-alkoxy radical, one of the radicals R2 and R4 represents a 1-3C-alkoxy radical and the other represents a hydrogen atom ( — H) or a 1-3C-alkyl radical.” Id. at 2:28-31.

An alkyl is a radical consisting of carbon and hydrogen atoms, arranged in a chain with the general formula CnH2n+i. A common example is methyl, — CH3. An alkoxy is a radical consisting of an alkyl group linked to oxygen. The most simple is methoxy, — OCH3. The only structural difference between compound 12 and pantoprazole is the substituent (or radical) at the 3-position of the pyridine ring. In compound 12, it is a methyl group ( — CH3), [1004]*1004whereas in pantoprazole, it is a methoxy group ( — OCH3).

On or about April 6, 2004, Teva filed an Abbreviated New Drug Application (“ANDA”) pursuant to the Hatch-Waxman Act, requesting FDA approval to sell a generic version of Protonix ® prior to the expiration of the '579 patent. Sun filed similarly directed ANDA applications on or about March 1, 2005, and June 25, 2005. Both Teva and Sun filed paragraph IV certifications in conjunction with their respective ANDA applications. Following the submission of these ANDA applications, Altana filed suit against Teva and, subsequently, against Sun. The district court consolidated these cases.

Altana filed a motion for preliminary injunction on June 22, 2007. In opposition to this motion, both Teva and Sun conceded infringement; however, they maintained that the '579 patent is invalid.1 Specifically, the defendants argued that the '579 patent was obvious in light of the teachings in the following prior art references: (1) Altana’s '518 patent, (2) the Sachs article,2 (3) the Bryson article,3 and (4) the '431 patent (covering omeprazole).

In the district court, the defendants’ obviousness analysis focused on the selection of compound 12 from the '518 patent as a lead compound for modification. The defendants argued that the Sachs article provided motivation for one of skill in the art to lower the pKa of a PPI to a value of 4 in order to provide better stability of the compound in the patient’s body. The pKa value of a compound is measured on a logarithmic scale, and indicates the degree of the willingness of the compound to accept or donate a proton. The lower the numerical pKa of a compound, the more acidic and less basic it is. Thus, at pH 5, a compound with a pKa of 4 would be more stable than the compound with a pKa of 5.

Free access — add to your briefcase to read the full text and ask questions with AI

Related

Cite This Page — Counsel Stack

Bluebook (online)
566 F.3d 999, 91 U.S.P.Q. 2d (BNA) 1018, 2009 U.S. App. LEXIS 10262, 2009 WL 1332741, Counsel Stack Legal Research, https://law.counselstack.com/opinion/altana-pharma-ag-v-teva-pharmaceuticals-usa-inc-cafc-2009.