Merck & Co., Inc. v. Sandoz Inc.
April 09, 2012
Drug Product and Patent(s)-in-Suit: Cancidas® (caspofungin acetate); U.S. Pat. No. 5,952,300 ("the '300 patent")
Nature of the Case and Issue(s) Presented: Merck moved for summary judgment on Sandoz's obviousness defense. The ‘300 patent claims formulations of a pharmaceutical containing caspofungin. Because the parties did not dispute that experimentation and a formulation process were needed to arrive at the solution addressed by the ‘300 patent-namely, the creation of a caspofungin formulation for intravenous administration-the only remaining issue for the Court to consider was whether the patented formulation was, from the start, obvious to try. Sandoz contended that the claimed formulation resulted from routine pharmaceutical development and experimentation, not invention. The Court disagreed, however, and granted summary judgment.
Why Merck Prevailed: To succeed on its invalidity defense and show that it would have been obvious to try the experimentation that resulted in the patented invention, Sandoz had to rely on "evidence that the skilled artisan, at the beginning of the development process, would have viewed the final outcome of the process as one of a finite number of identified, predictable solutions." The Court found this evidence missing from Sandoz's opposition. The Court distilled nearly two dozen undisputed facts into the following key points. First, it took two years of research and experimentation to develop the patented formulation. And in that process, the patentee discovered a number of path-determinative facts: (i) the solution formulation approach was unacceptable due to chemical degradation of caspofungin; (ii) the lyophilization approach with a tartrate buffer failed; (iii) experimental evidence showing pH drift resulted in the search for a buffer; and (iv) solution-stability experiments demonstrated caspofungin degradation at pH 5, but the acetate-buffered formulations turned out to be most stable when the pre-lyophilized solution had a pH of 6, which was outside acetate's normal buffering range. Sandoz did not explain how those results-achieving optimal stability at an out-of-range pH 6-could possibly have been expected. Moreover, lyophilization is a process that is, by Sandoz's expert's own admission, very hard to predict.
The Court held that it would be error to find that "obvious-to-try" proves obviousness in this case because "the prior art gives only general guidance to the form of the invention." Put another way, the prior art did not allow the skilled artisan to identify a finite number of specific, predictable solutions; instead, it offered only general guidance.
Further, it was undisputed that Merck's own scientists did not know why the acetate-buffered formulations were more stable than corresponding tartrate-buffered ones. This suggested, the Court reasoned, that the success of this combination was not predictable nor that there was a reasonable expectation of success in combining those elements. Merck also pointed out that before the development process began, the prior art contained no information about the stability of caspofungin or caspofungin formulations.
If you are interested in having us represent you, you should call us so we can determine whether the matter is one for which we are willing or able to accept professional responsibility. We will not make this determination by e-mail communication. The telephone numbers and addresses for our offices are listed on this page. We reserve the right to decline any representation. We may be required to decline representation if it would create a conflict of interest with our other clients.
By accepting these terms, you are confirming that you have read and understood this important notice.