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Par Pharm., Inc. v. TWi Pharms., Inc.

United States Court of Appeals for the Federal Circuit

December 3, 2014, Decided



 [*1188]  [***1947]   O'Malley, Circuit Judge.

This patent case involves methods of use of nanosized formulations of the drug megestrol acetate ("megestrol"). After a bench trial, the U.S. District Court for the District of Maryland found the asserted claims [**2]  of U.S. Patent No. 7,101,576 ("'576 patent") invalid as obvious. We vacate the district court's judgment of invalidity and remand for further analysis because the district court incorrectly applied our law on inherency in the context of obviousness.

The '576 patent claims methods of using megestrol nanoparticles to "increas[e] the body mass in a human patient suffering from anorexia, cachexia, or loss of body mass." '576 Patent col. 41 l. 63-col. 43 l. 8. Megestrol has long been used to treat wasting, initially for cancer patients. In 1993, Bristol-Myers Squibb began marketing an oral suspension of micronized megestrol,  [*1189]  named Megace OS, specifically for the treatment of anorexia and cachexia in AIDS patients. Megace OS proved to be a commercial success, and other manufacturers submitted Abbreviated New Drug Applications ("ANDAs") under the Hatch-Waxman Act to seek approval to market generic versions of Megace OS.

Par Pharmaceutical ("Par")1 applied for and received approval to market a generic micronized megestrol formulation. Par, however, continued to experiment with megestrol, including attempts at reformulating the drug by reducing the particle size from the micrometer range to the nanometer range. Par contracted with Alkermes Pharma Ireland ("Alkermes"), [**3]  née Elan Pharmaceuticals, to use its "NanoCrystal" technology to formulate nanosized megestrol.

After Alkermes produced megestrol nanoparticles, Par discovered that Megace OS demonstrated a strong food effect. Patients taking Megace OS with a meal showed a significantly higher rate and extent of absorption compared with those patients who took Megace OS while in a fasting state. The nanosized megestrol formulation, however, showed a greatly reduced food effect. A reduction in the food effect would be especially vital for AIDS patients undergoing wasting, as those patients often have substantially reduced appetites.

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773 F.3d 1186 *; 2014 U.S. App. LEXIS 22737 **; 112 U.S.P.Q.2D (BNA) 1945 ***


Subsequent History: On remand at, Injunction granted at Par Pharm., Inc. v. TWi Pharms., Inc., 2015 U.S. Dist. LEXIS 28147 (D. Md., Mar. 9, 2015)

On remand at, Findings of fact/conclusions of law at Par Pharm., Inc. v. TWi Pharms., Inc., 120 F. Supp. 3d 468, 2015 U.S. Dist. LEXIS 97977 (D. Md., 2015)

Injunction denied by Par Pharm., Inc. v. TWi Pharms., Inc., 2015 U.S. Dist. LEXIS 99326 (D. Md., July 30, 2015)

Motion denied by, Costs and fees proceeding at Par Pharm., Inc. v. TWi Pharms., Inc., 2016 U.S. Dist. LEXIS 133009 (D. Md., Sept. 27, 2016)

Prior History:  [**1] Appeal from the United States District Court for the District of Maryland in No. 1:11-cv-02466-CCB, Judge Catherine C. Blake.

Par Pharms., Inc. v. TWi Pharms., Inc., 2014 U.S. Dist. LEXIS 21704 (D. Md., Feb. 21, 2014)



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Patent Law, Nonobviousness, Evidence, Fact & Law Issues, Elements & Tests, General Overview, Prima Facie Obviousness, Jurisdiction & Review, Standards of Review, Clearly Erroneous Review, De Novo Review, Anticipation & Novelty, Accidental Anticipation & Inherency, Prior Art