No Single Case Lays Out All Facets of the Legal Test of Obviousness

Pfizer, Inc. v. Apotex, Inc., [06-1261](March 22, 2007)[MICHEL, Mayer, Linn] The Federal Circuit reversed the trial court's holding that Pfizer's U.S. Patent No. 4,879,303 on the hypertension drug Norvasc was valid.
BRIEF: In considering the obviousness the Federal Circuit noted that teaching, suggestion, or motivation "may be found in any number of source, including common knowledge, the prior art as a whole, or the nature of the problem itself." The Federal Circuit found motiviation from the prior art as a whole, bu also form the nature of the problem encoutered. The Federal Circuit was also persuaded by expert testimony supports the inference that one of skill in the art would have been encouraged, rather than discouraged, to make the claimed invention. Rather than an unlimited number of possible salts, the Federal Circuit found the choices limited to a limited number of pharmaceutically acceptable salts. The Federal Circuit found that the desirable property of besylate salts make their use obvious, despite the lack of similar besylate salt compounds. The Federal Circuit held found that unpredictability did not avoid obviousness, so long as there was a reasonable probability of success. Only a reasonable expectation of success, not a guarantee, is needed. The Federal Circuit said that to hva a reasonable expectation of success, one must be motivated to do more than merely vary all parameteres or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gve either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful. The Federal CIrcuit tried to reconcile the truism is not "obvious to try", with the fact that absolute predictability is not required, by explaining that each case must be decided on its own facts. Quoting from Dystar the Federal Circuit said: "Obviousness is a complicated subject requiring sophisticated analysis, and no single case lays out all facets of the legal test." The Federal Circuit found that because of the limited number of parameters, a reasonable expectation of success, numerous references suggesting the particular salt, that a besylate salt was obvious from the maleate salt. The art did more that teach a general approach that seemed to be promising. Finally on the particular facts of the case, that the "invention" was the product of routine experimentation to verify properties (as opposed to identify new compounds) also suggested obviousness.