Gerhard Schmidmaier et al.Download PDFPatent Trials and Appeals BoardOct 23, 201915091812 - (D) (P.T.A.B. Oct. 23, 2019) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 15/091,812 04/06/2016 Gerhard Schmidmaier 104525.007046 1093 53443 7590 10/23/2019 BakerHostetler Cira Centre, 12th Floor 2929 Arch Street Philadelphia, PA 19104-2891 EXAMINER SINGH, RANDEEP ART UNIT PAPER NUMBER 1615 NOTIFICATION DATE DELIVERY MODE 10/23/2019 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): eofficemonitor@bakerlaw.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE __________ BEFORE THE PATENT TRIAL AND APPEAL BOARD __________ Ex parte GERHARD SCHMIDMAIER, MICHAIL RASCHKE, and AXEL STEMBERGER __________ Appeal 2019-002654 Application 15/091,8121 Technology Center 1600 __________ Before RICHARD M. LEBOVITZ, DEBORAH KATZ, and RACHEL H. TOWNSEND, Administrative Patent Judges. TOWNSEND, Administrative Patent Judge. DECISION ON APPEAL This is an appeal under 35 U.S.C. § 134(a) involving claims to a fracture fixation device, which have been rejected as obvious. We have jurisdiction under 35 U.S.C. § 6(b). We reverse. STATEMENT OF THE CASE Appellant’s Specification explains that implants to stabilize a fracture and promote healing are known as are implants which are permanently bonded to the bone. (Spec. ¶ 3.) Appellant’s invention is directed to a 1 We use the word “Appellant” to refer to “Applicant” as defined in 37 C.F.R. § 1.42. Appellant is DePuy Synthes Products, Inc. who identifies the real party in interest as the named inventors. (Appeal Br. 1.) Appeal 2019-002654 Application 15/091,812 2 fracture fixation implant that has a biodegradable polymer coating that contains a biocidal or anti-infection substance. (Spec. ¶¶ 7, 35, and claim 9.) Claims 9–28 are on appeal. Claim 9 is representative and reads as follows: 9. A fracture fixation device comprising: a nail comprising a non-degradable metal or alloy base material having an outer surface; a polymer coating adhesively bonded on the outer surface of the nail, the polymer coating comprising a polylactide or polylactide interpolymer, or a blend thereof, wherein the coating has an average thickness of less than 30 microns; and, a biocidal or anti-infective active agent dispersed within the coating. (Appeal Br. 20.) The following ground of rejection by the Examiner is before us on review: Claims 9–28 under 35 U.S.C. § 103(a) as unpatentable over Fox,2 Kummer,3 Davidson,4 and Sinclair.5 DISCUSSION The Examiner finds that Fox teaches infection resistant medical devices that are prepared by dissolving a polymer matrix such as poly (L) or (D)-lactide in an organic solvent to form a dispersion, incorporating at least one antimicrobial agent therein, and coating the device with the polymer 2 Fox, Jr. et al., US 5,019,096, issued May 28, 1991. 3 Kummer et al., US 4,338,926, issued July 13, 1982. 4 Davidson, US 5,458,653, issued Oct. 17, 1995. 5 Sinclair et al., US 5,502,158, issued Mar. 26, 1996. Appeal 2019-002654 Application 15/091,812 3 matrix, which the Examiner finds meets the recited limitation of “a biocidal or anti-infective active agent dispersed within the coating” and that the coating be adhered to the outer surface. (Final Action 2–3; Ans. 4.) The Examiner finds that Fox teaches “that an advantage of using biodegradable polymers such as poly(L-lactide) and poly(D-lactide) in their coating matrix is to allow improved tissue ingrowth simultaneously with a prolonged antimicrobial effect as the biodegradable polymer degrades (see column 12, lines 13–17).” (Ans. 4.) The Examiner explains that while Fox does not specifically recite that the device is a fracture fixation device, it nevertheless discloses that the medical devices can be implants and the surfaces that can be coated can be metal. (Id. (citing Fox 3: 6–19).) To meet the corresponding limitations in the claim regarding the type of fracture fixation device, the Examiner further finds that Kummer teaches bone prostheses for use in healing a bone fracture such as nails, screws, and plates, that have their surface covered by a biologically absorbable element affixed or molded thereto. (Final Action 4.) The Examiner concludes that it would have been obvious to one of ordinary skill in the art to use the method of coating described in Fox to produce a coated infection-resistant orthopedic fracture fixation device like nails, screws, or plates as taught in Kummer with a reasonable expectation of success. (Id.) Regarding the claimed limitation that the polymer coating have a thickness of less than 30 microns, the Examiner recognizes that Fox does not explicitly recite polymer coatings having a thickness of less than 30 microns. (Final Action 4.) However, the Examiner finds that Fox teaches the thickness of the coating can be varied to achieve a desired thickness. (Id. at 3 (citing Fox 14:63–65).) Moreover, the Examiner finds that Fox teaches Appeal 2019-002654 Application 15/091,812 4 the antimicrobial particles are 5 microns or less (Ans. 7–8 (citing Fox 13:61– 68).) The Examiner also finds that Fox teaches “applying a powdered antimicrobial agent to an adhesive surface in micro layers so that minimum loss of adhesiveness occurs while imparting a high level of protection against growth of microorganisms to the surface.” (Id. at 8 (citing 15: 5–9).) The Examiner finds that Davidson teaches load-bearing skeletal replacement prostheses that are coated with a bioabsorbable polymer such as polylactide and that antibiotics may be added to the coating. (Final Action 5.) The Examiner further finds that Davidson teaches that “the selection of a polymer of a particular average molecular weight or range of molecular weights, copolymerization, and selection of coating thickness will fix the ‘life’ of the coating.” (Id.) Thus, the Examiner concludes that Davidson and Fox teach coating thickness is a known result effective variable and that one of ordinary skill in the art would have found it obvious to formulate via routine experimentation the coating layer thickness to be 30 microns or less to optimize the life of the coating. (Id.; Ans. 8). We disagree that the Examiner has established a prima facie case of obviousness, but solely on the limitation requiring the coating to have “an average thickness of less than 30 microns.” We will address Appellant’s other arguments first. Appellant’s argument that Fox as a whole does not suggest the specifically claimed metal fixation devices with polylactide coatings because it teaches a “narrower application of the disclosed [laundry list of] coatings” and surfaces onto which the coating may be applied and “denigrates such expansive lists disclosed in the prior art” (Appeal Br. 6) is not persuasive. Fox discloses that it determined combinations of polymeric coatings that Appeal 2019-002654 Application 15/091,812 5 were “superior to all other known polymeric coating materials” in the ability to provide an antimicrobial agent on the surface of a medical device to be retained and released in an active state over an appreciable period of time. (Fox 3:67–4:4, 7:22–25, 8:49–52 (“The superior characteristics of the biomedical polyurethanes, lines 20 and 21, are surprising, since the prior art does not hint or suggest that any one of the above polymer matrices is any better than any other.”).) Such a disclosure is not a denigration of a broad disclosure of the capability of polymers to adhesively bond to a surface, but rather an indication that some polymers may bond better than others. Appellant’s claim 9 simply requires that the polylactide that has the biocidal or anti-infective agent dispersed in it be adhesively bonded to the outer surface of the metal or alloy nail. We agree with the Examiner that Fox’s disclosure renders such a coating obvious because it discloses that polylactide polymers are suitable surface coatings (Fox 11:35–12:52) and expressly teaches devices made of metals (Fox 3:17–19) as required by all the claims. In re Longi, 759 F.2d 887, 897 (Fed. Cir. 1985) (“The fact that some titanium compounds function more effectively, and that the exact magnitude of the increased catalytic activity might not be predictable, does not preclude a conclusion of obviousness.”). It is true that Table II of Fox demonstrates that the adhesion of polymeric coatings on the surfaces of polyurethane catheters and latex catheters is not the same (Appeal Br. 8–9 (noting “GOOD” adhesion to urethane catheter but “POOR” adhesion to latex catheter)), and Fox teaches that “[s]election of the coating vehicle depends upon the specific composition of the surface of the device to be coated, and the characteristics sought” (Fox. 4: 5–7) and indicates that “[c]ertain solvent solutions Appeal 2019-002654 Application 15/091,812 6 containing certain polymers do not adequately wet latex surfaces” thereby resulting in a coating that is discontinuous or not adherent (id. at 13:10–16). However, Fox describes a method for determining polymers that would form stable coatings on a medical device that will contact an area of the human body either externally or internally. (Id. at 5:31–7:25.) Thus, we disagree with Appellant that “Fox does not provide the methodology to determine which surfaces, solvents and coatings successfully work with each other” (Appeal Br. 8). Appellant’s argument that Fox teaches the adhesive bonding required by the claims is unpredictable (Appeal Br. 10–12; Reply Br. 1), is not persuasive of the non-obviousness of the claimed invention. It is true that Example 5 demonstrates that polytetrafluoroethylene arterial graft material (Goretex) could not be adequately surface coated with polyurethane mixed with PLA and an antibacterial while polyethylene terephthalate arterial graft material (Dacron) could be, and that no explanation is provided as to why that is the case. (Fox 19–20.) However, such evidence does not demonstrate unpredictability of coating a non-degradable metal or alloy with a polylactide or polylactide interpolymer, or a blend thereof as claimed. In light of the fact that Fox teaches that the method of coating a medical device with a biodegradable polymer such as polylactide can be applied to medical implants and metal surfaces, we agree with the Examiner that one of ordinary skill in the art, using routine experimentation, would have had a reasonable expectation of success in using that method to coat a metal nail. “Reading a list and selecting a known compound to meet known requirements is no more ingenious than selecting the last piece to put into the last opening in a jig-saw puzzle. It is not invention.” Sinclair & Carroll Appeal 2019-002654 Application 15/091,812 7 Co. v. Interchemical Corp., 325 U.S. 327, 335 (1945); see also Merck & Co. Inc. v. Biocraft Laboratories, Inc., 874 F.2d 804, 807 (Fed. Cir. 1989). Furthermore, Kummer indicates that such a polylactide coating is compatible with metal nails used in the fixation of bone fractures. (Kummer 1–2; see also Kummer 3:22–31, 4:18–27.) Kummer differentiates between a coating that is molded onto a metallic structural member as opposed to a layer that is separable from the metallic structure and placed between the metallic structure and the bone surface to which the structural element is in abutment. (Compare id. 3:22–31 with id. 3:62–4:16.) While Kummer does not describe the polylactide coating that is molded to the metallic nail as one that is adhered to the metal so as to be molded onto it, Fox teaches that one can adhere such a coating to a metal surface using the described process. Thus, we agree with the Examiner that Kummer supports the conclusion that the claimed invention would have been obvious. Appellant argues that Kummer’s disclosure of the coating being “held under compression” does not provide any “basis for the examiner to allege equivalence between the claimed ‘adhesively bonded’ and ‘affixing’ or ‘molding’ disclosed in Kummer.” (Appeal Br. 12.) It is true that Kummer describes the coating being “held” under compression between the nail or plate and the bone fragments sought to be rejoined when the “prosthesis . . . is secured to the fragments” (Kummer 3:31–34, 4:34–40), just as a separable polylactide washer layer is described to be “held” under compression between the fixation device and bone fragment, but being so “held” so as to achieve compression does not preclude adherence of the polylactide continuous layer on the nail or plate. That is because the reference merely requires that polymeric material be compressed against the bone, which Appeal 2019-002654 Application 15/091,812 8 allows for “all of the stresses transmitted between bone fragments 8 and 9 [to be] transmitted through” the polylactide rather than “across the fracture line” and carried by the plate or nail. (Id. 3:36–41, 4: 37–46.) There is no evidence that the stresses would not be transmitted through the polylactide if it were adhered as a layer rather than simply being molded on. Appellant’s argument that Kummer employs polylactide coatings for a different purpose than the purpose provided in Appellant’s Specification (Appeal Br. 12) is also not persuasive. First, as the Examiner notes, the claims do not recite a functional purpose for the polylactide coating. (Ans. 6.) Moreover, it is not necessary that references be combined or modified for the same reasons as Appellant’s. “As long as some [reason,] motivation or suggestion to combine the references is provided by the prior art taken as a whole, the law does not require that the references be combined for the reasons contemplated by the inventor.” In re Beattie, 974 F.2d 1309, 1312 (Fed. Cir. 1992). Fox teaches that a polylactide composition can be a matrix to support an antimicrobial that can be coated on a medical device to prepare an infection resistant device. Kummer teaches the polylactide would serve as a stress-shield when the coating is applied to a nail or plate used in fracture fixation. We agree with the Examiner “that a skilled artisan would have readily appreciated, based on the teachings of Fox and Kummer, that it would be beneficial for a stress-shielding coating to incorporate an antimicrobial composition for infection treatment and resistance upon implantation.” (Ans. 6.) Turning now to the thickness of the coating limitation. Appellant argues that Davidson, while discussing thickness in the context of stress shielding and retarding bone growth does not recite any thickness values for Appeal 2019-002654 Application 15/091,812 9 the coating and the Examiner has admitted that Fox fails to disclose a coating thickness of less than 30 microns. (Appeal Br. 13–16.) We agree with Appellant that “[n]either Fox nor Davidson teach or provide any further guidance that narrows the universe of ‘variable’ thicknesses to what would motivate one skilled in the art to the particularly recited thickness range currently claimed.” (Id. at 16.) “[W]here there is a range disclosed in the prior art, and the claimed invention falls within that range, there is a presumption of obviousness.” Iron Grip Barbell Co. v. USA Sports, Inc., 392 F.3d 1317, 1322 (Fed. Cir. 2004). It is true, as the Examiner notes, that Fox teaches application of “micro layers” of the “powdered antimicrobial agent to an adhesive surface so that minimum loss of adhesiveness occurs while imparting a high level of protection against growth of microorganisms to the surface. (Fox 15: 5–9.) However, that teaching does not establish a range for the thickness of the adhesive layer. Even though Fox also teaches the use of micronized particles in coatings of 5 microns or less (id. at 13:65– 67), the size of micronized particles does not equate to the thickness of the micro layers. At best, Fox teaches a layer thickness range of greater than 5 microns. Thus, even accepting that Davidson suggests that the thickness of the polylactide coating is a result effective variable, there is no teaching of a thickness range in the prior art with an upper limit of less than 30 microns as required by all the rejected claims. Thus, there is no presumption of obviousness for the claimed range. Each of the independent claims has this same coating thickness layer limitation. Consequently, we reverse the Examiner’s rejection of claims 9–28 as being obvious over Fox, Kummer, Davidson and Sinclair. Appeal 2019-002654 Application 15/091,812 10 CONCLUSION In summary: Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 9–28 103 Fox, Kummer, Davidson, Sinclair 9–28 REVERSED Copy with citationCopy as parenthetical citation