Ex Parte Mandeville et al

Board of Patent Appeals and Interferences

Aug 25, 2003

08964498 (B.P.A.I. Aug. 25, 2003)

The opinion in support of the decision being entered today was not written
for publication and is not binding precedent of the Board.

Paper No. 34

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte W. HARRY MANDEVILLE, and STEPHEN RANDALL
__________

Appeal No. 2003-0564
Application No. 08/964,498
__________

ON BRIEF
__________

Before WILLIAM F. SMITH, SCHEINER, and GRIMES, Administrative Patent
Judges.

GRIMES, Administrative Patent Judge.

DECISION ON APPEAL

This is a decision on appeal under 35 U.S.C. § 134 from the examiner’s
final rejection of claims 9-18. Claims 1-8 and 19-28 are also pending but have
been withdrawn from consideration. See Paper No. 19, mailed Nov. 7, 2000.
Claim 9 is representative of the claims on appeal and is reproduced in an
appendix to this opinion.
1. A method for lowering the serum phosphate level of a patient
comprising administering to the patient a therapeutically
effective amount of a polymer characterized by a substituted
or unsubstituted diallylamine repeat unit.

Appeal No. 2003-0564 Page 2
Application No. 08/964,498

9. The method of Claim 1 wherein the polymer comprises a repeat
unit of the general formula

wherein R1 and R2 are each, independently, is hydrogen, a substituted or
unsubstituted, normal, branched or cyclic alkyl group, or a substituted or
unsubstituted aryl group; or R1, R2 and the nitrogen atom together form a cyclic
system; and X is a pharmaceutically acceptable anion.

The examiner relies on the following references:
Howes 2,090,605 Dec. 12, 1980
Holmes-Farley WO 95/05184 Feb. 23, 1995

Claims 9-18 stand rejected under 35 U.S.C. § 103 as obvious in view of
Howes and Holmes-Farley.1
We reverse.
Background
Elevated phosphate levels, or hyperphosphatemia, “frequently
accompanies diseases associated with inadequate renal function,
hypoparathyroidism, and certain other medical conditions.” Specification, page
1. The condition can cause “aberrant calcification in joints, lungs, and eyes.” Id.

1 The rejection based on Howes and Holmes-Farley is the only rejection applied to the claims,
despite the examiner’s statement that he “could just as well make the rejection combining newly
submitted Patent Document EPA 793960.” Paper No. 19, mailed Nov. 7, 2000, page 2. The ‘960
reference was not cited as a basis for the rejection, nor did the examiner provide any explanation
whatsoever of how it might form a basis for rejecting the claims. To the extent that the examiner
Appeal No. 2003-0564 Page 3
Application No. 08/964,498

Treatments for hyperphosphatemia include “oral administration of
insoluble phosphate binders to reduce gastrointestinal absorption.” Id.
Phosphate binders that have been used in such therapies include calcium salts,
aluminum salts, and ion exchange resins. See id., pages 2-3. All of these
agents, however, can cause serious side effects. See id.
The specification discloses a method of lowering the serum phosphate
level of a patient by administering a polymer having diallylamine repeat units.
These poly(diallylamine) polymers are disclosed to have “excellent phosphate-
binding activity.” Page 4.
Discussion
Claim 9, the broadest claim on appeal, is directed to a method for lowering
the serum phosphate level in a patient by administering a therapeutically
effective amount of a poly(diallylamine) that comprises repeat units having one of
two recited structures. The structures comprise a heterocyclic, five- or six-
membered ring that includes a quaternary ammonium group.
The examiner rejected the claimed method as obvious in view of Howes
and Holmes-Farley. The examiner’s statement of the rejection reads as follows:
[Howes] teaches polymers comprising heterocyclic diallyl
ammonium monomers (Abstract). [Holmes-Farley] teaches
phosphate binding polymers for treating hyper phosphatemia
(Abstract). Quaternary amines are specified (claim 31).

It would have been obvious to one of ordinary skill to use the
polyallylamines of [Howes] to treat hyper phosphatemia in view of

intended to imply an alternative basis for the rejection, we vacate any implied rejection based on
references other than Howes and Holmes-Farley.
Appeal No. 2003-0564 Page 4
Application No. 08/964,498

the teaching of [Holmes-Farley] that quaternary polyallylamines are
effective for so treating.

Paper No. 19, mailed Nov. 7, 2000, page 2.
Appellants argue that the cited references do not support a prima facie
case of obviousness. See the Revised Brief on Appeal, page 5: Howes
“discloses antimicrobial polymers with diallyl repeat units but does not suggest
using the polymers for treating hyperphosphatemia,” while Holmes-Farley does
not suggest using polymers of cyclic diallyl monomers, such as those of Howes,
for treating hyperphosphatemia. Appellants conclude that, at best, “the
Examiner has shown that the disease state is known to be treated by a different
product and that a polymer falling within the scope of some of the claims is
known to treat a different disease.” Id., page 7.
“In rejecting claims under 35 U.S.C. § 103, the examiner bears the initial
burden of presenting a prima facie case of obviousness. Only if that burden is
met, does the burden of coming forward with evidence or argument shift to the
applicant.” In re Rijckaert, 9 F.3d 1531, 1532, 28 USPQ2d 1955, 1956
(Fed. Cir. 1993). An adequate prima facie case requires, among other things,
evidence showing that those of ordinary skill in the art would have been led to
combine the elements known in the prior art in such a way as to yield the claimed
invention. See In re Kotzab, 217 F.3d 1365, 1369-70, 55 USPQ2d 1313, 1316
(Fed. Cir. 2000) (“[T]o establish obviousness based on a combination of the
elements disclosed in the prior art, there must be some motivation, suggestion or
Appeal No. 2003-0564 Page 5
Application No. 08/964,498

teaching of the desirability of making the specific combination that was made by
the applicant.”).
An adequate showing of motivation to combine requires “evidence that ‘a
skilled artisan, confronted with the same problems as the inventor and with no
knowledge of the claimed invention, would select the elements from the cited
prior art references for combination in the manner claimed.’” Ecolochem, Inc. v.
Southern Calif. Edison Co., 227 F.3d 1361, 1375, 56 USPQ2d 1065, 1075
(Fed. Cir. 2000).
In this case, we agree with Appellants that the examiner has not shown
that the claimed method would have been obvious based on the cited references.
Howes discloses heterocyclic polymers comprising quaternary ammonium units
that fall within the formulas recited in the instant claims. Howes, however, does
not disclose that the polymers are useful for treating hyperphosphatemia or that
they have properties (e.g., phosphate binding) that would suggested such a use.
Instead, Howes discloses that the polymers have antimicrobial activity and are
useful for sterilization of contact lenses and for treatment of bacterial infection of
the skin. See the abstract.
Holmes-Farley teaches treatment of hyperphosphatemia using phosphate-
binding polymers comprising tertiary or quaternary ammonium units. The
polymers disclosed by Holmes-Farley, however, are made up of acyclic subunits
and therefore do not fall within the formulas recited in the instant claims. See
pages 3-7. Nor does Holmes-Farley suggest that all polymers comprising tertiary
or quaternary ammonium units would work in the disclosed method.
Appeal No. 2003-0564 Page 6
Application No. 08/964,498

Rather, the method is disclosed to require “oral administration . . . of a
composition containing at least one phosphate-binding polymer that is non-toxic
and stable once ingested.” Page 2. Holmes-Farley defines “non-toxic” to mean
that “neither the polymers nor any ions released into the body upon ion exchange
are harmful,” and defines “stable” to mean that “the polymers do not dissolve or
otherwise decompose to form potentially harmful by-products, and remain
substantially intact so that they can transport bound phosphate out of the body.”
Page 3.
The examiner has argued that “the fact that both the polymers of [Holmes-
Farley] and [Howes] contain quaternary amine groups would inform one of
ordinary skill that, with regard to methods of use of [sic] implicating the
quaternary amine, the polymers will be functionally similar.” Examiner’s Answer,
page 4. We understand this to mean that, in the examiner’s view, those of skill in
the art would have expected both Holmes-Farley’s polymers and Howes’
polymers (and any other polymer comprising quaternary ammonium units) to
bind phosphate.
The examiner has presented no evidence to support this position, but it
would make no difference if he had. Even assuming the examiner is correct,
Holmes-Farley clearly discloses that not all phosphate-binding polymers are
appropriate for use in treating hyperphosphatemia. In addition to binding
phosphate, the polymers must also be non-toxic and stable, as those terms are
defined by Holmes-Farley. The examiner has presented no evidence that those
skilled in the art would have recognized Howes’ polymers as meeting these
Appeal No. 2003-0564 Page 7
Application No. 08/964,498

criteria. Therefore, the examiner has not shown that the references would have
suggested combining Howes’ polymers with Holmes-Farley’s method, in the
manner required to yield the presently claimed invention. The rejection under
35 U.S.C. § 103 is reversed.
Summary
The references cited by the examiner, viewed without the benefit of
hindsight, would not have suggested the method claimed by Appellants. We
therefore reverse the rejection under 35 U.S.C. § 103.

REVERSED

William F. Smith )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
Toni R. Scheiner )
Administrative Patent Judge ) APPEALS AND
)
) INTERFERENCES
)
Eric Grimes )
Administrative Patent Judge )

EG/dym
Appeal No. 2003-0564 Page 8
Application No. 08/964,498

David E. Brook
Hamilton Brook Smith & Reynolds
530 Virginia Road
P.O. Box 9133
Concord, MA 01742-9133