Ex Parte Loo et alDownload PDFPatent Trial and Appeal BoardDec 6, 201713885931 (P.T.A.B. Dec. 6, 2017) 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. 13/885,931 07/16/2013 Say Chye Joachim Loo 42870-0003 1898 112088 7590 12/08/2017 Schiff Hardin LLP, New York 666 Fifth Aveue Suite 1700 New York, NY 10103 EXAMINER PURDY, KYLE A ART UNIT PAPER NUMBER 1611 NOTIFICATION DATE DELIVERY MODE 12/08/2017 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): lbrutman @ schiffhardin.com patents-NY @ schiffhardin.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte SAY CHYE JOACHIM LOO, KELSEN BASTARI, and SUBRAMANIAM VENKATRAMAN Appeal 2016-006730 Application 13/885,9311 Technology Center 1600 Before TAWEN CHANG, TIMOTHY G. MAJORS, and RACHEL H. TOWNSEND, Administrative Patent Judges. TOWNSEND, Administrative Patent Judge. DECISION ON APPEAL This is an appeal under 35U.S.C. § 134 involving claims to a method for coating particles with calcium phosphate, which have been rejected as obvious. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. STATEMENT OF THE CASE “Calcium phosphate (CaP) is a family of minerals that contains calcium cations and phosphate anions, of which these could be orthophosphates, metaphosphates or pyrophosphates.” (Spec. 13.) 1 Appellants identify the Real Party in Interest as Nanyang Technological University. (Appeal Br. 2.) Appeal 2016-006730 Application 13/885,931 Appellants’ invention is directed at “a method for coating particles which are negatively charged with calcium phosphate (CaP).” (Id. | 5.) Claims 1—9 and 11—18 are on appeal. Claim 1 is representative and reads as follows: 1. A method for coating particles with calcium phosphate (CaP), wherein the particles are negatively charged, the method comprising: adding a base to a first solution containing calcium ions to maintain the pH in the range of about 10 to 12 and contacting the particles with the first solution; removing the first solution to obtain a precipitate; and adding a base to a second solution containing phosphate ions to maintain the pH in the range of about 10 to 12 and contacting the precipitate with the second solution to obtain CaP-coated particles. (Appeal Br. 10.) The following ground of rejection by the Examiner is before us on review: Claims 1—9 and 11—18 under 35 U.S.C. § 103 as unpatentable over Xu2 and Yokogawa.3 DISCUSSION The Examiner finds that Xu teaches “a method of using a single solution of calcium and phosphate to provide a CaP-coating onto a particle and Yokogawa teaches that CaP-coatings can be provided with separate calcium and phosphate solutions.” (Ans. 5; see also Final Action 5—6.) The 2 Xu et al., WO 2008/149096 A2, published Dec. 11, 2008. 3 Yokogawa et al., US 6,153,266, issued Nov. 28, 2000. 2 Appeal 2016-006730 Application 13/885,931 Examiner notes that “Yokogawa is cited to demonstrate that CaP-coatings can be applied to surfaces by applying separate calcium and phosphate solutions as opposed to Xu’s single solution process” (Ans. 6), and that one of ordinary skill in the art would recognize “the process of Yokogawa as a suitable alternative to depositing a CaP layer onto the particle of Xu” (id. at 4; see also Final Action 3 (“Xu desires the same outcome as Yokogawa, e.g., deposit a calcium phosphate coating/layer.”)). The Examiner concludes that using the two step process of Yokogawa would have been an obvious modification of Xu as a simple substitution to obtain a predictable result. (Ans. 4.) Moreover, the Examiner explains that Xu indicates calcium phosphate may precipitate out of solution, even though Xu desired to provide a calcium phosphate coating to the surface of a particle. (Final Action 3.) The Examiner explains that it would have been obvious to use the two step process of Yokogawa rather than Xu’s one step process in which calcium phosphate may precipitate out of solution “to more efficiently provide a calcium phosphate coating and reduce the amount of precipitate formed which is not depositing as a coating layer.” (Id. ) We agree with the Examiner’s factual findings and conclusion that the method of claim 1 would have been obvious from the disclosure of Xu and Yokogawa. Appellants argue the Examiner’s rejection is in error because “the principle of operation of the invention of Xu is to form the CaP-coated particles using one solution containing both calcium and phosphate ions” and not as two separate solutions of calcium ions and phosphate ion (Appeal Br. 5), and Yokogawa “fails to cure the deficiencies of Xu” because it is “related to coating a surface of a substrate” and not coating particles (id. at 3 Appeal 2016-006730 Application 13/885,931 6). As to Xu, Appellants contend that Xu is “fundamentally different” from the two solution process claimed, and teaches away from a two solution process because “it endorses using one solution containing both calcium and phosphate ions,” and because “Xu only encapsulates hydrophilic drug compounds” whereas the claimed invention “allows for encapsulation of hydrophilic, hydrophobic, and amphiphilic compounds without compromising on the final drug encapsulation amount in the final product.” (Id. at 5—6.) Appellants further argue that Yokogawa is non-analogous art. (See id. at 7; Reply Br. 3.) We do not find Appellants’ arguments persuasive. It is true that Xu teaches a single solution process. However, the Examiner’s rejection is one that is based on a modification of Xu that the Examiner concludes would have been obvious in light of the teachings of Yokogawa. (See Ans. 4—5 (“Xu provides a method of using a single solution of calcium and phosphate to provide a CaP-coating onto a particle and Yokogawa teaches that CaP-coatings can be provided with separate calcium and phosphate solutions.”); Final Action 6—7 flflf 26—27).) “Non obviousness cannot be established by attacking references individually where the rejection is based upon the teachings of a combination of references. . . . [The reference] must be read, not in isolation, but for what it fairly teaches in combination with the prior art as a whole.” In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986). Furthermore, we do not find that Xu teaches away from using separate solutions to provide a CaP coating on particles. Xu teaches that it is desirable to avoid long immersion times so as to avoid a change in the polymer properties of a biodegradable polymer (Xu 2), and provides a 4 Appeal 2016-006730 Application 13/885,931 methodology that accomplishes such a result. However, we do not find that disclosure to be one that would discourage one of ordinary skill in the art from an alternative method for providing a CaP surface coating on a polymer, such as the two solution method taught by Yokogawa. In addition, we do not find either Xu or Yokogawa to be non- analogous art. Whether Xu might only encapsulate hydrophilic drug compounds is not relevant to the claimed invention, which is directed to a method for coating particles with CaP and does not require any drug encapsulation. While Appellants contend that their invention is directed at obtaining an ideal bone-targeting system that has good targeting capabilities and properties close to bone tissues (Appeal Br. 7), we note that this is achieved by obtaining a CaP coating on the surface of a particle (see Spec. 12 (“The invention relates to a method of coating particles, and in particular, to a method of coating particles with calcium phosphate”); Spec.l 6 (“According to another aspect of the invention, there is provided a microparticle comprising a negatively charged particle coated with calcium phosphate (CaP), wherein calcium ions of the CaP are absorbed onto the surface of the negatively charged particle”)). We find Yokogawa’s teachings related to coating a surface of a substrate, of which “[n]o particular limitation [as to kind] is imposed” (Yokogawa 5:6—8), to obtain a CaP coating thereon is reasonably pertinent to a problem with which the inventor is involved and is therefore analogous art. Moreover, Yokogawa explains that the method described “enables formation of a homogeneous coating film containing hydroxyapatite on a surface regardless of the kind and size of the substrate.” (Yokogawa 2:11—12.) Hydroxyapatite is Caio(P04)6(OH)2 and is considered by Appellants’ Specification to be CaP. (Spec. 121.) 5 Appeal 2016-006730 Application 13/885,931 Appellants argue that Yokogawa would not be used to “‘deconstruct’ Xu’s method of making calcium phosphate coated particles” as the Examiner argued, because Yokogawa indicates that using two separate solutions may not result in “a coating film consisting solely of hydroxyapatite” and that an additional solution is required (Appeal Br. 7), and thus, teaches away from the claimed invention (Reply Br. 5—6). This argument is not persuasive as Appellants’ claim 1 is not directed to a coating consisting only of hydroxyapatite, but rather simply requires obtaining CaP- coated particles. According to Appellants’ Specification, “[cjalcium phosphate (CaP) is a family of minerals that contains calcium cations and phosphate anions.” (Spec. 13.) In other words, CaP need not be a single material coating the surface of the particle. Yokogawa teaches that a CaP coating will result when using one solution containing calcium and a separate second solution containing phosphate ions, or vice versa, although the CaP coating may include a hydroxyapatite precursor. (Yokogawa 4:13— 26 (describing Ca ions added before P ions); 6:15—26 (describing P ions added before Ca ions); 8:28-48 (Example 9).) As Yokogawa explains, such a precursor “refers to calcium phosphate compounds,” such as for example tricalcium phosphate (TCP) or dicalcium phosphate dihydrate. (Yokogawa 4:5—12.) Thus, the hydroxyapatite precursor is also a CaP composition within the scope of the claims. Furthermore, we agree with the Examiner that claim 1, which recites the transition phrase “comprising”, does not exclude additional unrecited steps. Invitrogen Corp. v. Biocrest Mfg., L.P., 327 F.3d 1364, 1368 (Fed. Cir. 2003) (“The transition ‘comprising’ in a method claim indicates that the claim is open-ended and allows for additional steps.”) Consequently, the additional step included in Yokogawa 6 Appeal 2016-006730 Application 13/885,931 of adding a third solution such that the CaP coating would be deposited solely as hydroxyapatite is not excluded by the language of claim 1. The Examiner explains, and we agree, “that it [would have been] obvious to add each of calcium and phosphate independently and expect the result to be substantially the same [as that achieved by Yu]” in light of the teachings of Yokogawa. (Final Action 6—7.) “[T]he test of obviousness is not express suggestion of the claimed invention in any or all of the references but rather what the references taken collectively would suggest to those of ordinary skill in the art presumed to be familiar with them.” In re Rosselet, 347 F.2d 847, 851 (CCPA 1965). Xu teaches coating particles with CaP by providing a solution comprising both calcium and phosphate. Yokogawa, on the other hand, teaches that CaP coatings can be accomplished by adding separate solutions of calcium ions and phosphate ions. (Xu 4:5—15.) Yokogawa teaches that to coat a surface with CaP, including organic polymer materials (Yokogawa 5:6—8), no matter the order of adding the ions is interchangeable and notes that phosphate ions can be added with a pH as high as 11.5 or as low as 8 and the Ca ions can be added with a pH as high as “12 or more” or as low as 7.3. (See, e.g., Yokogawa Ex. 1—5, and Ex. 9—13.) Yokogawa further teaches that changes in pH of both Ca and P solutions is a result effective variable as to the amount of hydroxyapatite being deposited on the surface, and that an increase in pH increases the amount deposited. (See, e.g., id. at Ex. 11 to 13 (explaining that when the pH of the P solution was 9 or 9.6, the “hydroxyapatite is deposited in an amount greater than in the case in which the pH is 8,” and at Ex. 6 to 8 explaining that when the pH of the Ca solution was 9 or 10, the 7 Appeal 2016-006730 Application 13/885,931 “hydroxyapatite is deposited in an amount greater than in the case in which the pH is 8,” with 10 having a higher deposition that 9). In light of the foregoing, we agree with the Examiner that the prior art as a whole indicates that separating the solution of Xu into component parts would have been obvious to one of ordinary skill in the art with a reasonable expectation of success in light of the teachings of Yokogawa. In re O’Farrell, 853 F.2d 894, 903-04 (Fed. Cir. 1988) (“Obviousness does not require absolute predictability of success. ... For obviousness under § 103, all that is required is a reasonable expectation of success.”); see also KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007) (“If a person of ordinary skill can implement a predictable variation [of a known work], § 103 likely bars its patentability.”). Appellants argue that Yokogawa fails to teach the pH limitations because in the process Examples 9 and 10 describing the addition of calcium ions prior to phosphate ions, the pH of the calcium ion solution is only 7.3. (Appeal Br. 7—8; Reply Br. 8.) We do not find this argument persuasive. While Appellants are correct that in Examples 9 and 10 of Yokogawa the pH of the calcium solution is less than what is claimed, as we noted above, Yokogawa when read as a whole, indicates that the pH of the calcium solution and the phosphate solution are result effective variables. Yokogawa teaches that in a process to obtain a CaP coating on a substrate with separate solutions of calcium ions and phosphate ions, a calcium ion solution having a pH of “12 or more” is feasible. (Yokogawa Ex. 5.) In light of these teachings, we find that it would have been obvious to optimize the pH of both the calcium ion solution and the phosphate ion solution in a process in which the calcium ion solution is the first of the two solutions used in the 8 Appeal 2016-006730 Application 13/885,931 process to obtain a CaP coating. In re Boesch, 617 F.2d 272, 276 (CCPA 1980) (“[Djiscovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art.”). Appellants’ argument that they have provided evidence of unexpected results sufficient to establish the claims are not obvious from Xu and Yokogawa is also unpersuasive. According to Appellants, sufficient calcium phosphate coating is achieved with particles being in contact with the first solution for 10 minutes and in contact with the second solution for 2.5 minutes. (Appeal Br. 8; Reply Br. 10.) In comparison, Appellants argue that Xu and Yokogawa both require a contact/soaking period of at least several hours. (Id.) First, we note that claim 1 does not require a particular amount of CaP to be deposited on the particle or that soaking the particle in a solution be limited to a particular time period. “It is well established that the objective evidence of nonobviousness must be commensurate in scope with the claims.” In re Lindner, 457 F.2d 506, 508 (CCPA 1972). The basis for “commensurate in scope” requirement is that a claim which reads on both obvious and nonobvious subject matter is unpatentable under § 103. See In re Muchmore, 433 F.2d 824, 826 (CCPA 1970). As the Examiner points out, Appellants’ dependent claim 11 indicates that the contact time for the first solution can be anywhere from about 5 minutes to about 5 hours, and dependent claim 12 indicates the contact time for the second solution can be anywhere between about 2 minutes and 3 days. Thus, Appellants’ claim 1 is much broader in scope than the evidence of unexpected results, i.e., contact with the first solution for 10 minutes and contact with the second solution for 2.5 minutes. Thus, even if it might be the case that Appellants achieved a CaP coating in less 9 Appeal 2016-006730 Application 13/885,931 time than Yokogawa’s method, claim 1 (and claims 11 and 12) does not preclude the lengths of time that may be required by Yokogawa. Moreover, “[t]o be particularly probative, evidence of unexpected results must establish that there is a difference between the results obtained and those of the closest prior art, and that the difference would not have been expected by one of ordinary skill in the art at the time of the invention.” Bristol-Myers Squibb Co. v. leva Pharms. USA, Inc., 752 F.3d 967, 977 (Fed. Cir. 2014). We note that Appellants’ evidence does not provide a comparison against Yokogawa’s two step processes to establish Yokogawa would not result in deposition of CaP if the soaking time was for less than what was described in the Examples of Yokogawa. Rather, Appellants simply point to Yokogawa’s disclosure as showing the soaking time in the phosphate solution was for 24 hours and not 2.5 minutes. (Appeal Br. 8; Reply Br. 10 (“throughout the entire disclosure of Yokogawa, the contact/soaking period for Step 2 (i.e., for the second (calcium) solution) is at least several hours to several tens of hours . . . (see, e.g., Yokogawa, col. 4, lines 56-57 (‘is several hours to several tens of hours for Step 2’) and Example 1 — ‘24 hours’)”). Thus, for this additional reason, we do not find Appellants’ argument as to unexpected results to be sufficiently persuasive to overcome the evidence of obviousness. For the reasons discussed, Appellants do not persuade us that the Examiner erred in maintaining the obviousness rejection of claim 1. Claims 2—9 and 11—18 have not been argued separately (Appeal Br. 9) and therefore, fall with claim 1. 37 C.F.R. § 41.37(c)(l)(iv). 10 Appeal 2016-006730 Application 13/885,931 SUMMARY We affirm the rejection of claims 1—9 and 11—18 under 35 U.S.C. § 103 as unpatentable over Xu and Yokogawa. TIME PERIOD FOR RESPONSE No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). AFFIRMED 11 Copy with citationCopy as parenthetical citation