Amgen, Inc. v. Hoechst Marion Roussel, Inc. (now known as Aventis Pharmaceuticals, Inc.), et al.
Phrase “Therapeutically Effective Amount” Was Incorrectly Construed by the District Court.
On appeal from U.S. District Court for the District of Massachusetts, the CAFC held that the district court erred in construing the term “therapeutically effective amount.”
The technology at issue relates to recombinant DNA technology for the production of the hormone erythropoietin, or EPO. This hormone stimulates the production of red blood cells in the bone marrow and is used to treat disorders characterized by low amounts of red blood cells.
Simply stated, claim 1 of the ‘422 patent recites: “A pharmaceutical composition comprising a therapeutically effective amount of human EPO.” The district court construed the phrase “therapeutically effective” to mean an amount to increase hematocrit (ratio of red blood cells to total blood cells) AND useful in healing or curing certain patients. Consequently, the primary issue on appeal was whether the scope of claim 1 was limited to products that increase hematocrit?
Using Phillips v. AWH as a guide, the CAFC looked to the ‘422 specification to construe the phrase. The specification indicated that the therapy is used to produce “any or all” of five particular “effects,” just one of which is increasing hematocrit. Additionally, during prosecution the patentee cited particular language in the specification as a description of what would be “therapeutically effective.” The CAFC held that it was an artificial distinction to separate hematocrit increases from the other effects. Accordingly, the proper consruction of “therapeutically effective amount” is one that produces at least one of the effects, and that does not necessarily require an increase in hematocrit.
Under this understanding of the claim terms, the CAFC vacated judgements of of invalidity and remanded with respect to claim 1 of Amgen’s U.S. Pat. No. 5,547,933 (the ‘933 patent) and infringement of claims 2-4 of U.S. Pat. No. 5,621,080 (the ‘080 patent). The CAFC also affirmed the judgment of validity and infringement of Amgen’s U.S. Pat. No. 5,618,698 (the ‘698 patent), and U.S. Pat. No. 5,756,349 (the ‘349 patent).