St. Jude Med., Cardiology Div., Inc. v. The Bd. of Regents of the Univ. of Mich.

In the final written decision of an inter partes review, the Patent Trial and Appeal Board (PTAB) canceled all claims at issue on obviousness grounds, rejecting the patentee’s argument that the patented features’ commercial success evinced the patent’s nonobviousness.  St. Jude Med., Cardiology Div., Inc. v. The Bd. of Regents of the Univ. of Mich., IPR No. IPR2013-00041 (PTAB, May 1, 2014) (Crumbley, APJ).

The patent at issue is directed to a method of increasing the calcification resistance of glutaraldehyde-tanned biomaterials.  Prior to implantation, biomaterials are typically tanned with glutaraldehyde to prevent degradation.  Tanning does, however, increase the likelihood of calcification.  The patent teaches that treating the tanned biomaterial with aqueous solutions of greater than 50 percent aliphatic alcohol renders the biomaterial more calcification-resistant.  The patent further teaches that the biomaterial should be rinsed following treatment, and one embodiment describes treating the biomaterial with trivalent cations.

The PTAB concluded that the challenged claims would have been obvious in light of the prior art.  Three prior art references were asserted.  In the first, Levy disclosed treating tanned biomaterials with trivalent cations in aqueous solution to prevent calcification, and states that organic solvents can be used, including aliphatic alcohols.  That reference also discloses rinsing the treated biomaterial. The second disclosed storing tanned biomaterials in 50 percent aliphatic alcohol solutions.  The third taught treating biomaterials with high concentrations of alcohols to prevent rejection or reabsorption.

The PTAB found that all elements of the claims at issue are taught by one or more of the prior art references.  The patentee argued that there would be no reason to combine these references, because Levy is directed to making tissue calcification-resistant, whereas Kaplan merely mentions calcification in the context of storing tanned biomaterials, and the third addresses using ethanol as a sterilant.  The PTAB disagreed, finding that Kaplan teaches one of skill in the art to treat tanned biomaterials in alcohol solutions to prevent calcification, and gives one a reason to substitute such a solution into Levy’s method.  The PTAB found that all three references teach treating tanned biomaterials with aliphatic alcohols, and Kaplan and Holman show that high concentrations of alcohol are not toxic.

The patentee presented evidence of the commercial success of products that practice the patent, but the PTAB found that the patentee failed to establish a nexus between the commercial success of its products and the claimed invention.  The patentee provided absolute sales numbers, but the PTAB did not find this evidence meaningful because it was not comparative data.  The patentee also relied on marketing materials that touted the patented features, but this evidence was countered by testimony that unpatented features weighed more heavily in the purchasing decisions.  The patentee also failed to persuade the PTAB that there was a long-felt need because both Levy and Carpentier disclosed effective anticalcification methods, and the mere fact that existing products can be improved is not proof of long-felt but unmet need.