Hatch-Waxman Litigation: Invalidating “Public use” need not be the intended use of the invention, as long as the invention is fully disclosed without restriction

We generally do not see the claims of the patents invalidated under prior public use as it is critically difficult to establish and support the evidence. But in an interesting decision on September 12, 2013, (Pronova Biopharma Norge v. Teva Pharmaceuticals USA, No. 2012-1498), Federal Circuit unanimously held the asserted claims of Pronova's U.S. Patent No. 5,656,667 invalid as anticipated by prior public use, reversing a District of Delaware trial decision in the process. The grounds for reversing the District Court's finding that the defendant had not established invalidity under the public use statutory bar under 35 U.S.C. § 102(b) was based on the Court's determination that Pronova's predecessor in interest had permitted unrestricted use of formulations falling with the scope of the claims and disregarded Pronova's argument that public use was negated because there was insufficient evidence that the use was for the inventions' intended.

The case concerned U.S. Patents Nos. 5,502,077 and 5,656,667 involved in ANDA litigation between Pronova and, in separate ANDAs, Teva and Par Pharmaceuticals, who propounded Paragraph IV letters contending that these patents were invalid and non-infringed by their generic formulations of the branded drug Lovaza®.

The main facts surrounding defendants' arguments for an invalidating public use involved transfer of samples of formulations falling within the scope of the asserted claims by Pronova' predecessor in interest in the patents, all of which occurred prior to the critical date of the '677 patent. These transfers included samples sent to Dr. Victor Skrinska, with disclosure of the contents of the formulations, with no restrictions, confidentiality requirements, or obligations to report the results of any experiments performed using the formulations. Dr. Skrinska analyzed the contents of the formulations but did not perform any testing on the clinical use or benefits of the formulations.

Federal circuit held that the disclosure by transfer of samples of the formulation constituted an invalidating public use. Factors supporting this determination were that the transfer contained no evidence of confidentiality restrictions and the fact that Pronova conceded there was no experimental use involved in this transfer. The panel concluded that the transfer was "with no secrecy obligation or limitation for [Dr. Skrinska's] unfettered use" and that the shipment of the formulations "made public all aspects of the claimed inventions, since it included a certificate of analysis revealing the composition of the supplied products." It was also undisputed that Dr. Skrinska was "one highly skilled in the art, with the full ability to know, understand, and fully disclose the invention to others.

Federal circuit also said that they are not persuaded by Pronova’s argument that “use” of a pharmaceutical formulation cannot occur until it is used to treat the condition it is intended to counteract (to reduce triglyceride level in this case), or at least physically ingested.

Below are the important take away points from the decision regarding “Public Use”:

(1)   Unrestricted Use of the invention falls under Public use;

(2)   Confidentiality Agreement should be in place so as to avoid unrestricted use;

(3)   Strictly Experimental Use may overcome invalidating attack under Public use.

(4)   Public Use not necessarily should be the intended use, as described in patent