Print PDF

Cyclosporin “Hydrosol” Must Be Formed Outside Patient’s Body

April 02, 2004
Holtman Ph.D., M. Andrew

Decision icon Decision

Last Month at the Federal Circuit - May 2004

Judges: Dyk (author), Prost, and Clevenger (dissenting)

In Novartis Pharmaceuticals Corp. v. Eon Labs Manufacturing, Inc., No. 03-1211 (Fed. Cir. Apr. 2, 2004), the Federal Circuit affirmed the district court’s grant of SJ that U.S. Patent No. 5,389,382 (“the ‘382 patent”) was not infringed by Eon Labs Manufacturing, Inc.’s (“Eon”) manufacture and sale of tablets.

The ‘382 patent, owned by Novartis Pharmaceuticals Corporation (“Novartis”), provides a formulation for cyclosporin that addresses problems inherent with the use of the drug. Cyclosporin is an immunosuppressive drug used to reduce the risk of organ rejection after transplantation. The drug’s application, however, was limited by its low solubility in water, which made it less absorbable in the human body. The ‘382 patent provides cyclosporin as a hydrosol, which is more soluble.

The principal issue on appeal was whether the meaning of “hydrosol,” as used in the claims of the ‘382 patent, is limited to medicinal products prepared outside the body or includes products formed within the stomach of the patient upon ingestion. This distinction is decisive since neither party disputed that Eon’s tablet is hydrosolfree prior to ingestion by the patient. The district court’s claim interpretation required a meaning of the term “hydrosol” to exclude conversion in the patient’s stomach.

The Federal Circuit began its claimconstruction analysis with an examination of a general purpose dictionary. It determined that a definition of “hydrosol” yields two competing definitions: (a) a medicinal preparation consisting of a dispersion of solid particles in an aqueous colloidal solution prepared outside the body, or (b) a dispersion of solid particles in aqueous colloidal solution formed in a patient’s stomach. Thus, the term “hydrosol” is ambiguous.

To resolve the dispute, the Court looked to the intrinsic record. It noted that the specification consistently refers to the hydrosol of the ‘382 patent in terms of a “pharmaceutical” composition. A “pharmaceutical” is defined in the dictionary as a “medicinal drug,” which, according to the Federal Circuit, is a drug that necessarily must be made outside the body. The Court pointed to an additional claimed aspect of the hydrosol—an intravenous injection form—as further support of this definition.

Lastly, the Federal Circuit considered the prosecution history. It concluded that because Novartis had previously argued before the PTO to overcome an obviousness rejection that the drug was of a size sufficient to be administered by intravenous injection, it too supports the narrower definition of the term “hydrosol.”

Having determined that the narrower meaning of the term “hydrosol” applied, the Court found no direct infringement of the ‘382 patent. And, because there can be no induced or contributory infringement without the underlying direct infringement, the Federal Circuit affirmed the district court’s grant of SJ against Novartis. The Court also affirmed the district court’s grant of SJ of no infringement under the DOE because a holding to the contrary would vitiate the claimed requirement that the dispersion be prepared outside the body.

Judge Clevenger disagreed with the majority’s use of the tools of claim interpretation. He argued that hydrosol must be given its full breadth of meaning, absent the patentee’s clear disavowal of scope that alters the ordinary meaning, and that the patentee was denied that interpretation when the majority chose to construe terms further removed from the term at issue.