The U.S. Court of Appeals for the Federal Circuit concluded the claims of a patent directed to a medical device for implementation into humans were enabled by animal tests or in vitro data where human testing is inappropriate.  Edwards Lifesciences AG v. CoreValve, Inc., Case No. 11-1215; -1257 (Fed. Cir., Nov. 13, 2012) (Newman, J.).

Edwards sued CoreValve in district court for infringement of a patent directed to a prosthetic device called a “transcatheter heart valve.” The valve is mounted on a collapsible stent and implanted in the heart by a balloon catheter, thereby avoiding open heart surgery and its associated risks.

CoreValve challenged the validity of the patent for lack of enablement based on the undisputed fact that at the time the patent application was filed, the stent/valve prosthesis had been implanted only in pigs and that testing in pigs did not enable use in humans.  CoreValve pointed out that the various experimental implants in pigs were not always successful and that design changes were made after the patent application was filed. 

Edwards did not deny that more developmental work was required at the time of filing. One of the co-inventors had stated, in a contemporaneous report, that “questions such as size reduction, material and design optimization, and stent valve sterilization, remain unsolved,” and that “much more work had to be done before anybody ever even contemplated using this for a human.” Edwards’ expert witness testified that at the time the patent application was filed, it was a device to perform testing on and not a device to move in and treat patients.

Nonetheless, the jury found for Edwards, and the lower court found the patent was enabled.  CoreValue appealed. 

The Federal Circuit affirmed. Citing the Manual of Patent Examining Procedure, the Court explained that it has long been recognized that when experimentation on human subjects is inappropriate, as in the testing and development of drugs and medical devices, the enablement requirement may be met by animal tests or in vitro data. The Court confirmed this general rule, which has been elaborated in various situations.

To determine whether the subject matter claimed required undue experimentation, the Court considered the In re Wands factors. The Court reasoned that there was evidence that the stent/valve prosthetic device was successfully implanted in pigs, that pigs were a standard experimental animal for heart valve research, and that witnesses for both sides discussed the vascular anatomies of pigs and the established use of porcine valves in humans.

As such, the Court concluded that substantial evidence supported the jury verdict that invalidity on the ground of non-enablement had not been proved by clear and convincing evidence.