Ex Parte Loo et al

Patent Trial and Appeal Board

Dec 6, 2017

13885931 (P.T.A.B. Dec. 6, 2017)

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.
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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
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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
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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.)
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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
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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
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“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
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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
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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).
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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
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