Know Your Handbook
In Aventis Pharma S.A. v. Hospira Inc., No. 2011-1018 (Federal Circuit April 9, 2012), the court relied on disclosure in a non-patent literature reference in its decision.
The case involved US Patents No. 5,750,561 and 5,714,512 directed to compositions containing taxane derivatives (compounds found in yew trees; cf.). The patents are assigned to Aventis Pharma S.A. Consolidated actions were brought by Aventis Pharma S.A. and Sanofi-Aventis U.S., LLC against Hospira Inc, Apotex Inc., and Apotex Corp. for patent infringement. In an earlier ruling, the district court had found the patents in suit to be invalid for obviousness and unenforceable due to inequitable conduct, and entered a judgment in favor of defendants. The plaintiffs then appealed from the earlier district court decision. The Federal Circuit recently affirmed the district court’s judgment.
Both involved patents are pharmaceutical patents related to a class of chemotherapy cancer drugs called taxanes. Taxanes are administered through i.v. infusion, whereby the drug is delivered in aqueous solution. Due to their poor solubility in water, taxanes are typically mixed with surfactants in order to achieve more stable aqueous solutions. In the prior art, the surfactant Cremophor was used with taxanes. However, Cremophor has been known to have side effects such as triggering serious allergic reactions (aka anaphylactic reactions which may cause death; cf. ).
The invention claimed in either patent in suit is drawn to aqueous mixtures of the taxane derivative docetaxel with polysorbate surfactant. Reportedly, use of polysorbate 80 surfactant avoids the anaphylactic manifestations associated with the use of the prior art surfactant Cremophor.
In its findings of the patents in suit to be invalid for obviousness and unenforceable due to inequitable conduct, the district court in no small part relied on the Vidal reference. A closer look at that citation reveals it to be the Dictionnaire Vidal―the French Physician’s Desk Reference or the French equivalent of the American PDR (Physician’s Desk Reference).
As noted by the Federal Circuit, the Vidal reference discloses use of polysorbate 80 surfactant with the cancer drug etoposide (a toxin found in American Mayapple; cf. ). With regards to the disclosure in the Vidal reference, the district court had found that (i) claim 5 of US Patent No. 5,750,561 was obvious in light of it, (ii) it was material to both patents’ patentability, and (iii) the inventors had intentionally withheld it with the intent to deceive the USPTO. The Federal Circuit affirmed.
When I read the case with its twists and turns I felt like reading a “whodunit.” This is practice of patent law “as good as it gets” in terms of suspense. Consider this—patentee brings suit against an alleged infringer. In the end, the court not only sides with the alleged infringer, but patentee also loses their patents in the process. The case, in no small part, turns on disclosure in a handbook.
Know your handbook―lest you lose the patent.
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