The Federal Circuit focused on the “consisting of” language in the claims at issue when it reversed the district court’s finding that Watson’s ANDA product would infringe the only Orange Book-listed Shire Lialda patent. In so doing, the court emphasized the narrow scope of the Norian exception to the “closed” nature of “consisting of” language that applies only for “aspects unrelated to the invention.”

The Lialda Patent At Issue

The patent at issue was Shire’s U.S. Patent 6,773,720, which is the only Orange Book-listed patent for Lialda®, which is approved for treating Crohn’s disease and ulcerative colitis. The patent relates to a pH-independent controlled release formulation of mesalazine (also known as 5-amino-salicylic acid or 5-ASA). Independent claim 1 is set forth below, with the “closed” language at issue highlighted:

1. Controlled-release oral pharmaceutical compositions containing as an active ingredient 5-amino-salicylic acid, comprising:

a) an inner lipophilic matrix consisting of substances selected from the group consisting of unsaturated and/or hydrogenated fatty acid, salts, esters or amides thereof, fatty acid mono-, di- or triglycerides, waxes, ceramides, and cholesterol derivatives with melting points below 90°C, and wherein the active ingredient is dispersed both in said the lipophilic matrix and in the hydrophilic matrix;

b) an outer hydrophilic matrix wherein the lipophilic matrix is dispersed, and said outer hydrophilic matrix consists of compounds selected from the group consisting of polymers or copolymers of acrylic or methacrylic acid, alkylvinyl polymers, hydroxyalkyl celluloses, carboxyalkyl celluloses, polysaccharides, dextrins, pectins, starches and derivatives, alginic acid, and natural or synthetic gums;

c) optionally other excipients; wherein the active ingredient is present in an amount of 80 to 95% by weight of the total composition, and

wherein the active ingredient is dispersed both in the lipophilic matrix and in the hydrophilic matrix.

The ‘620 patent withstood Inter Partes Review and survived a written description challenge that almost went all the way to the Supreme Court.

The Finding Of Non-Infringement

The outer matrix of Watson’s ANDA product includes magnesium stearate, which is not listed in the Markush group of claim 1(b). Thus, as noted by the Federal Circuit, “the claim 1(b) limitation is literally violated.”

Nevertheless, the district court found infringement because the magnesium stearate was found to be “unrelated to the invention,” and so–the district court thought–could be present notwithstanding the “consists of” clause under Norian Corp. v. Stryker Corp., 363 F.3d 1321, 1331 (Fed Cir. 2004).

The Federal Circuit Decision

The Federal Circuit decision was authored by Judge Hughes and joined by Chief Judge Prost and Judge Taranto.

The Federal Circuit explained the “rare exception” to the “closed” nature of “consisting of” language that was found in Norian.

In Norian, we considered whether adding a spatula to a calcium phosphate chemical kit designed to repair teeth and bones took the accused product outside the scope of the asserted patent. …. The claim at issue contemplated only aspects of the chemicals themselves:

8. A kit for preparing a calcium phosphate mineral, said kit consisting of:

at least one calcium source and at least one phosphoric acid source free of uncombined water as dry ingredients; and

a solution consisting of water and a sodium phosphate, where the concentration of said sodium phosphate in said water ranges from 0.01 to 2.0 M and said solution has a pH in the range of about 6 to 11.

We concluded that “[i]nfringement is not avoided by the presence of a spatula, for the spatula has no interaction with the chemicals, and is irrelevant to the invention.”

The Federal Circuit disagreed that the magnesium stearate in Watson’s ANDA product was sufficiently unrelated to the invention to fall under this “rare exception.” Although the district court had held that the magnesium stearate “is unrelated to the invention because it is not sufficiently lipophilic to render the outer matrix lipophilic,” the Federal Circuit explained that “related” components are not limited “to only those that advance or are intended to advance a Markush group’s allegedly inventive elements.”

The Federal Circuit dug into the facts and determined that the magnesium stearate was related to the invention for the following reasons:

Here, the district court concluded that the “magnesium stearate in the extragranular space is overwhelmed by the hydrophilic properties of the sodium starch glycolate in the extragranular space” …. The district court thereby found that the magnesium stearate exerted lipophilic influence in the outer matrix, and that finding is well supported …. No one has suggested that magnesium stearate, when in the outer matrix, is neither lipophilic nor hydrophilic. Thus, we conclude that, based on the district court’s findings, the magnesium stearate retains its lipophilic character in the extragranular space. Accordingly, the magnesium stearate structurally and functionally relates to the invention, and its presence in the outer matrix violates the “consisting of” requirement in claim 1(b).

The Federal Circuit therefore reversed the district court’s finding of infringement.

How Unrelated Is “Unrelated”

Adding a spatula to a chemical kit seems quite different from adding an ingredient to a chemical composition. Nevertheless, the Federal Circuit’s detailed analysis suggests that the “rare exception” to the “closed” nature of “consisting of” language may be broader than the situation at issue Norian, although it is not broad enough to encompass the magnesium stearate at issue here.