A “public use” of a claimed invention, by anyone, prior to the critical date will render the corresponding patent claims invalid (or unpatentable), if the invention, at the time of the public use, was ready for patenting. Accordingly, a proper analysis of whether a use constitutes a public use has always involved an inquiry into, first, whether the invention was “ready for patenting,” and secondly, whether the use was in fact public or not. Sanofi v. Glenmark Pharms. Inc., 204 F.Supp.3d 665, 697 (D. Del. Aug. 31, 2016) (citing Invitrogen Corp. v. Biocrest Mfg., L.P., 424 F.3d 1374, 1379 (Fed. Cir. 2005)).
Under pre-AIA Section 102(b), the public use had to be carried out within the United States and more than one year prior to the filing of a patent application in order to be invalidating. Under the AIA, a public use may be invalidating whether it occurred within or outside the United States, with a similar but weaker one year grace period applying. While the U.S. Patent and Trademark Office has not opined on whether an experimental use exception remains under the AIA, public use does clearly still remain an impediment to patentability. Since the AIA uses similar language defining invalidating public use it can be expected that pre-AIA case law and principles will remain relevant, but time shifted to reflect the first to file realities of the AIA.
Under well established pre-AIA case law, an invention was deemed to have been “ready for patenting” if it had been reduced to practice or if drawings and/or descriptions of the invention had been prepared that were sufficiently specific to enable one of ordinary skill in the art to practice the claimed invention. Pfaff v. Wells Elecs., 525 U.S. 67-68 (1998); In re Omeprazole Patent Litig., 490 F.Supp.2d 381, 505 (S.D.N.Y. 1998). Courts analyze the totality of the circumstances when determining whether or not a particular use is sufficiently “public” for purposes of Section 102(b). Janssen Pharmaceutica N.V. v. Eon Labs. Mfg., Inc., 134 F. App’x 425, 430 (Fed. Cir. Jun. 23, 2005). Use of a claimed invention will be deemed “public” if it is accessible to the public or was commercially exploited. Sanofi, 204 F.Supp.3d at 697 (citing Invitrogen, 424 F.3d at 1380). Accordingly, secrecy alone does not necessarily prevent a public use finding. Invitrogen, 424 F.3d at 1380.
A finding that the use under consideration was carried out for purposes of experimentation negates application of the public use bar. Invitrogen, 424 F.3d at 1379-80; Sanofi, 204 F.Supp.3d at 697. For example, proof of reduction to practice prior to the alleged public use is often relied upon by patent challengers in an effort to establish that the invention was ready for patenting at the time of the use. Reduction to practice, however, requires that an invention be shown to work for its intended purposes. Sanofi, 204 F.Supp.3d at 697. If experimentation is still on-going, then, necessarily, the invention has not been shown to work for its intended purpose. Id. Courts consider the following factors when assessing whether or not a use is experimental: (1) the length of the test period; (2) any confidentiality agreement (though the presence or absence of a confidentiality agreement is generally not dispositive); (3) any records of testing; (4) any monitoring and control of the test results; (5) the number of tests; and (6) the length of the test period in relation to tests of similar inventions. Eli Lilly and Co. v. Zenith Goldline Pharms., Inc., 471 F.3d 1369, 1381 (Fed. Cir. 2006).
The legal principles set out above, while seemingly straight-forward enough, leave ample room for case-specific interpretation and application when it comes to the question of whether the use of a claimed invention in connection with carrying out clinical trials will constitute an invalidating public use. Patent applications are typically filed early on in the process of developing and commercializing a pharmaceutical drug product. One reason for this approach is to secure the earliest possible filing date thereby pre-dating as much would-be prior art as possible. Such would-be prior art, however, is not limited to that published or otherwise emanating from others but also includes time bars such as the public use bar. The circumstances under which clinical trials involving administration of a drug product that occur prior to the critical date may constitute an invalidating public use is a murky area of the law and courts’ decisions in this area are highly dependent on the facts of the case before them.
Based on a review of the relevant case law, a patentee trying to avoid a finding that the clinical trials conducted in connection with its drug development efforts constitute an invalidating public use would benefit from taking the below precautions to the extent it is clinically/technically, financially, and administratively feasible to do so.
- Keep the number of subjects/patients enrolled in the trial to the smallest number that is commensurate with obtaining the necessary safety and/or efficacy data. Janssen Pharmaceutica, 134 F. App’x at 431.
- Monitor closely the conduct of the trial and patients’ related activities. , 134 F. App’x at 431; Eli Lilly and Co. v. Zenith Goldline Pharms., Inc., 364 F.Supp.2d 820, 912 (S.D. Ind. 2005).
- Instruct the participating physicians to maintain all details relating to the study confidential and to not share information regarding the study with others not involved; preferably have the physicians sign a confidentiality agreement. Dey, L.P. v. Sunovion Pharms., Inc., 715 F.3d 1351, 1357-58 (Fed. Cir. 2013); Bayer Schering Pharma AG v. Barr Labs., Inc., C.A. No. 05-cv-2308 (PGS), 2008 WL 628592, at *39-*41 (D.N.J. Mar. 3, 2008); Sanofi, 204 F.Supp.3d at 699.
- Have restrictions in place as to whom physicians may provide the study drug (e.g., patients, nurses and other critical support staff). Janssen Pharmaceutica, 134 F. App’x at 431; Dey, L.P., 715 F.3d at 1356.
- Refrain from accepting any money for the trial. Janssen Pharmaceutica, 134 F. App’x at 431.
- Have a detailed study protocol in place and require strict adherence to the protocol. Janssen Pharmaceutica, 134 F. App’x at 431.
- Require subjects/patients to maintain usage logs and ask that they return any unused doses of the study drug. Janssen Pharmaceutica, 134 F. App’x at 431.
- Have measures in place to ensure secure storage of the study drug by test administrators. Dey, L.P., 715 F.3d at 1356.
- Refrain from disclosing the specifics of the formulation of the study drug to the participating physicians and to the patients enrolled in the study if possible, particularly where the patent claims are directed to the drug product formulation. Dey, L.P., 715 F.3d at 1356; Pronova Biopharma Norge AS v. Teva Pharms. USA, Inc., 549 F. App’x 934, 941 (Fed. Cir. 2014); Sanofi, 204 F.Supp.3d at 699; Bayer Schering Pharma AG, 2008 WL 628592, at *39-*40; In re Omeprazole, 490 F.Supp.2d 381, 508-09 (S.D.N.Y. May 31, 2007).
- Maintain restricted access to all study centers. Eli Lilly and Co., 364 F.Supp.2d at 912.
- If the claimed invention has already been shown to work for its intended purpose, do not labor under the misconception that one-year clock has not begun to run because clinical trials are on-going. Sanofi, 204 F.Supp.3d at 697.
- In a similar vein to above, if a significant amount of clinical data bearing on the safety and efficacy of the claimed subject matter has already been collected and analyzed, be aware that the fact that the drug remains in clinical trials does not mean that the one-year clock has not yet started to run. In re Omeprazole Patent Litig., 490 F.Supp.2d at 505-06.
- Instruct those involved in the study that no further use of the study medication (aside from administration to subjects) is permitted. Janssen Pharmaceutica, 134 F. App’x at 431.
- To the extent disclosure of the claimed invention to anyone other than patients, physicians, and those acting under patients’ or physicians’ direction becomes necessary, understand that the higher the skill level of the person(s) to whom disclosure is made the more likely that such disclosure will render the clinical study a public use. Pronova Biopharma, 549 F. App’x at 943.
While both the “ready for patenting” and the “public” prongs of the public use analysis are fact-intensive, case-specific analyses, adhering to the above guidance will unquestionably significantly increase the probability of side-stepping public use defenses based on a patentee’s own clinical trials. Consistent with above, care should be taken not only with respect to design and implementation of the patentee’s clinical studies, but also with respect to decisions as the timing of the filing of patent applications directed to inventions that will be used in connection with carrying out the clinical studies.