Recent Federal Circuit Decision Illustrates Challenges in Proving Obviousness

This non-precedential decision is of interest not for any new exposition of patent law but merely as a convenient marker to demonstrate how far the pendulum has swung away from the recent loose standards allowing disparate references to be combined to support an obvious rejection of a patent claim. In the district court below, a bench trial on a Hatch-Waxman infringement suit brought against defendants Dr. Reddy’s and Teva by Genzyme and Sanofi resulted in a decision for the plaintiffs. The court held that the defendants had failed to prove that the sole claim in issue (claim 19) was invalid for obviousness and as infringement was not disputed the verdict of infringement was entered. The technology in the case related to a method for mobilizing and harvesting stem cells in a subject by first treating the subject with G-CSF and then with plerixafor thereby increasing the number of stem cells available for harvesting from the blood for use in treating leukemia by transplantation.

The defendants had relied on a combination of references to effectuate an obviousness defense. In a first combination, a paper by Hendrix et al. was cited to show that plerixafor produced increased white blood cells (WBCs) in the circulation. The authors suggested that the action of this agent may cause “release of WBCs from the endothelium and/or stem cells from bone marrow.” (emphasis added). To this was added the teaching from US Patent No. 5,824,304 to the effect that an antibody blocking agent which disrupts the anchoring of stem cells through a different receptor in conjunction with treatment with G-CSF achieved mobilization of stem cells in the peripheral blood. The district court did not find this combination persuasive first holding that the use of different receptors in their mode of action, the different end uses (transfusion vs. HIV) and the failure of the Hendrix researchers to actually test for the presence of stem cells in the blood made the two references non-analogous art.

Additionally, the court further held that, even if the references should be considered analogous art, the fact that numerous failed attempts littered the stem cell mobilization and harvesting art which would have made a person of ordinary skill in that art believe that combining the references as suggested could not be done with any reasonable expectation of success.

A unanimous panel of the CAFC affirmed this decision after review employing the clear error standard. The CAFC followed the district court’s analysis and accepted all the distinctions found over the combined references that negated what appears on the surface to be a reasonable combination of teachings as to the action of the two agents, plexiform and G-CSF, in mobilizing stem cells in the circulation. If in fact we can expect more decisions from the CAFC supporting the validity of patents in situations involving obviousness considerations, then we may at last be free of the restrictive holdings on patentability which followed the few Supreme Court decisions on obviousness which led to this judicial headwind.