Ex parte Barenholz et al.

Board of Patent Appeals and Interferences

Jan 31, 2001

08238149 (B.P.A.I. Jan. 31, 2001)

1
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written for publication and is not binding precedent of the Board.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. 26

UNITED STATES PATENT AND TRADEMARK OFFICE

__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES

__________

Ex parte YECHEZKEL BARENHOLZ
and ELISHALOM YECHIEL

__________

Appeal No. 1997-1913
Application 08/238,1491

__________

ON BRIEF
__________

1 According to appellants, this application is a continuation of 07/986,664, filed
January 22, 1993, now abandoned; which is a continuation of 07/714,069, filed July 10,
1991, now abandoned; which is a continuation of 07/323,516, filed March 14, 1989, now
abandoned; which is a continuation of 06/832,929, filed February 24, 1986, now U.S.
Patent 4,812,314.

2

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

SCHEINER, Administrative Patent Judge.

DECISION ON APPEAL

This is an appeal under 35 U.S.C. ? 134 from the final rejection of claims 23
through 25, all of the claims remaining in the application. Appellants state at page 3 of the
Brief of February 22, 1996, that the claims are divided into two groups, the first consisting
of claims 23 and 25, and the second consisting of claim 24, and provide arguments as to
separate patentability. Claims 23 and 24 are representative of the two groups, and read
as follows:
23. A method of reversing age-related changes in heart muscle cells in a subject,
comprising
intravenously administering to the subject, in a therapeutically effective amount,
liposomes having a lipid component comprising phosphatidylcholine having an acyl chain
composition which is characteristic, at least with respect to transition temperature, of the
acyl chain components of phosphatidylcholines in the heart cells of the subject at a younger
age, said liposomes being substantially free of sphingomyelin, and
repeating said administering over a period of at least several days until a significant
drop in the subject?s serum creatinine phosphokinase is observed.

24. The method of claim 23, wherein the phosphatidylcholine is egg
phosphatidylcholine.

The references relied on by the examiner are:

Williams et al. (Williams), ? Intravenously Administered Lecithin Liposomes: A Synthetic
Antiatherogenic Lipid Particle,? Perspectives in Biology and Medicine, Vol. 27, No. 3, pp.
417-31 (1984)

UK Pat. App. (Taylor) 2 089 681 Jan. 30, 1982

Appeal No. 1997-1913
Application 08/238,149

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In reaching our decision on this appeal we have given careful consideration to
appellants' specification and claims, and to the respective positions articulated by
appellants and by the examiner. We refer to the Examiner's Answer (Paper No. 23, mailed
April 24, 1996) for the examiner's reasoning in support of the rejection. For appellants'
arguments, we refer to the Brief (Paper No. 21, filed February 22, 1996) and the Reply
Brief (Paper No. 24, filed June 27, 1996). We note that in Paper No. 25, mailed July 17,
1996, the examiner acknowledged the Reply Brief and indicated that it had been entered.
Claims 23-25 stand rejected under 35 U.S.C. ? 103(a). As evidence of
obviousness, the examiner relies upon Williams in combination with Taylor. We reverse.
BACKGROUND
Claim 23, the sole independent claim on appeal, is drawn to a method of reversing
age-related changes in heart muscle cells in a subject. According to page 8, lines 17-19,
of the specification, these changes include a decrease in phosphatidylcholine (PC) levels
and a concomitant increase in sphingomyelin (SM) and cholesterol levels. The method is
carried out by intravenous administration of a therapeutically effective amount of a
liposome which comprises PC, and which is substantially free of sphingomyelin.
Appellants state at page 8, lines 19-22, that the liposomes "are designed to promote
exchange of PC from liposomes to heart cell membrane, and exchange of SM from the
heart muscle to the liposomes." The PC employed has "an acyl chain composition which
is characteristic, at least with respect to transition temperature, of the acyl chain
Appeal No. 1997-1913
Application 08/238,149

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components of PC in the heart cells of the subject at a younger age." The specification
states at page 9, lines 13-17, that the acyl chain length and the degree of acyl chain
saturation increase with age. The administration is repeated "over a period of at least
several days" until there is a significant drop in the serum creatinine phosphokinase level of
the subject. Guidance as to the dosage and timing of the administration is provided in the
specification at pages 13-14 and 19-20.
DISCUSSION
Claims 23-25 stand rejected under 35 U.S.C. ? 103(a) over Williams in combination
with Taylor. The examiner bears the initial burden of establishing a prima facie case of
obviousness under 35 U.S.C. ? 103. In re Warner, 154 USPQ 173, 177 (CCPA 1967). In
so doing, he or she must consider every limitation of the claimed invention. See In re
Royka, 490 F.2d 981, 180 USPQ 580, 582-83 (CCPA 1974); In re Wilson, 165 USPQ
494, 496 (CCPA 1970) ("All words in a claim must be considered in judging the
patentability of that claim against the prior art").
Claim 23 requires that the PC employed have "an acyl chain composition which is
characteristic, at least with respect to transition temperature, of the acyl chain components
of PC in the heart cells of the subject at a younger age." According to the specification
(see page 9, lines 13-17), both the acyl chain length and the degree of acyl chain saturation
increase with age. Thus, we agree with appellants that the requirements of claim 23 are
Appeal No. 1997-1913
Application 08/238,149

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not satisfied by intravenous administration of any arbitrary PC.2 Rather, for any given
subject, claim 23 requires intravenous administration of a PC having an objectively
determined transition temperature (a function of the acyl chain composition). The
specification indicates that one such PC can be egg PC.
Williams teaches that intravenous administration of PC (lecithin) results in
regression of atherosclerosis, and attributes this to the ability of intravenously injected
lecithin to form circulating liposomes which "take up cholesterol from many sources,
including the arterial wall.? Page 417, second paragraph. Intravenous administration of
preformed lecithin liposomes has a similar effect. Page 422. According to Williams,
? lecithin liposomes appear ideally suited as injectable, antiatherogenic lipid particles.?
Page 426. The examiner acknowledges that Williams "may not specify the lecithin or PC
used is pure or purified egg (yolk) lecithin." Examiner's Answer, page 3. Appellants agree

2 Natural PC, or lecithin, "comprises a mixture of the diglycerides of fatty acids (e.g.,
stearic, palmitic, myristal, linoleic, and oleic acids) linked to the choline ester of phosphoric
acid and is found in all living plants and animals." Taylor at page 2.
Appeal No. 1997-1913
Application 08/238,149

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and emphasize that Williams? disclosure of PC (lecithin) liposomes is generic, and not all
lecithin liposomes would meet the requirements of claim 23. Reply Brief, page 2.
The examiner relies on Taylor to address this deficiency in Williams. Taylor
discloses colloidal suspensions of liposomes formed from egg yolk lecithin (page 2, lines
30-31, and page 4, lines 39-40). According to the examiner, ? it would have been obvious
to one skilled in the art to use pure or purified egg (yolk) lecithin as the lecithin in the
method of [Williams] because Taylor [] discloses it as commercially available and also
suitable for administration to human or lower animals.? Examiner?s Answer, page 4.
Appellants point out, however, that Taylor's egg yolk lecithin is distearoyl lecithin, a
synthetic molecule manufactured commercially by hydrogenating egg yolk lecithin (see
page 2, lines 30-31), but the egg PC of the invention "is predominantly 1-palmitoyl, 2-oleyl
PC and 1-palmitoyl, 2-linoleyl PC" (Reply Brief, page 2; and page 9, lines 21-24, of the
specification). According to the specification at page 9, lines 13-17, hydrogenation
(saturation) is a characteristic of PC in aging subjects. The examiner acknowledged and
entered the Reply Brief, but did not respond to this or any other point raised therein. Thus,
it appears that the examiner failed to fully appreciate or address all the requirements of
claim 23. In our view, and in the absence of a fact-based analysis to the contrary,
administration of hydrogenated egg PC does not satisfy those requirements.
35 U.S.C. ? 103 requires that obviousness be determined based on the claimed
subject matter as a whole. Where, as here, the determination of obviousness is based on
Appeal No. 1997-1913
Application 08/238,149

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less than the entire claimed subject matter, the examiner?s conclusion is legally unsound
and cannot stand. On this record, we reverse the examiner?s rejection of the claims under
35 U.S.C. ? 103.3
The decision of the examiner is reversed.
REVERSED

Sherman D. Winters )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
William F. Smith )
Administrative Patent Judge ) APPEALS AND
)
) INTERFERENCES
)
Toni R. Scheiner )
Administrative Patent Judge )

3 Because we conclude that the examiner failed to make out a prima facie case of
obviousness as to claim 23, the sole independent claim, we need not specifically address
the remaining arguments raised in appellants' Brief and Reply Brief as to separate
patentability of claim 24.
Appeal No. 1997-1913
Application 08/238,149

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