Ex Parte Johnsen et al

Patent Trial and Appeal Board

Nov 16, 2012

12621556 (P.T.A.B. Nov. 16, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte HANNE JORUNN H. JOHNSEN, LARS TERJE HOLMAAS,
TROND KJERNLI, and OLE MAGNE HOMESTAD
__________

Appeal 2012-001716
Application 12/621,556
Technology Center 1600
__________

Before DONALD E. ADAMS, STEPHEN WALSH, and
SHERIDAN K. SNEDDEN, Administrative Patent Judges.

SNEDDEN, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a process
for the large-scale production of the compound iodixanol. The Examiner
has rejected the claims as obvious and indefinite. We have jurisdiction
under 35 U.S.C. § 6(b). We reverse-in-part, vacate-in-part, and enter three
new grounds of rejection.

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Application 12/621,556

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STATEMENT OF THE CASE
According to Appellants, the invention relates to “the synthesis of
iodixanol (1,3-bis(acetamido)-N,N'-bis[3,5-bis(2,3-
dihydroxypropylaminocarbonyl)-2,4,6-triiodophenyl]-2-hydroxypropane),
more specifically to the dimerisation of 5-acetamido-N,N'-bis(2,3-
dihydroxypropyl)-2,4,6-triiodo-isophthalamide with propyleneglycol as
solvent.” (Spec. 1.)
Claims 1-4 are on appeal and provide as follows:
1. Process for the dimerisation of 5-acetamido-N,N'-bis(2,3-
dihydroxypropyl)-2,4,6-triiodo-isophthalamide (Compound A)
in
a temperature range of about 10 to about 20°C
using propyleneglycol as solvent in a concentration of
about 0.8 to about 1.3 ml solvent per g Compound A
in the presence of about 0.3 to about 0.4 mole
equivalents of epichlorohydrin relative to Compound A, and
wherein the reaction solution has a pH value of about
11.5 to about 12.0, and
wherein the amount of backpeaks does not exceed 2% at
55 - 60% conversion of Compound A to iodixanol. (Emphasis
added).

The claims stand rejected as follows:
I. Claims 1-4 under 35 U.S.C. § 112, second paragraph, as being
indefinite.
II. Claims 1-4 under 35 U.S.C. § 103(a) as being unpatentable over
US Patent No. 5,349,085 to Hansen et al. (issued Sep. 20, 1994),
US Patent No. 6,974,882 B2 to Homestad (issued Dec. 13, 2005),
US Patent No. 6,232,499 B1 to Malthe-Sorenssen et al. (issued
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Application 12/621,556

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May 15, 2001), or US Publication No. 2009/0253935 A1 to
Cervenka et al. (published Oct. 8, 2009).
III. Claims 1-4 under the judicially-created doctrine of obviousness-
type double patenting as being unpatentable over claims 1-4 of
copending Application 12/621,571 in view of Hansen, Homestad,
Malthe-Sorenssen or Cervenka.
IV. Claims 1-4 under the judicially-created doctrine of obviousness-
type double patenting as being unpatentable over claims 1-4 of
copending Application 12/621,551 in view of Hansen, Homestad,
Malthe-Sorenssen or Cervenka.

I.
Issue
The Examiner has rejected claims 1-4 under 35 U.S.C. § 112, second
paragraph, as being indefinite. The Examiner finds that “[t]he specification
does not offer a context by which those of ordinary skill would understand”
or measure the recited backpeaks which Applicant intends to cover. (Ans.
8.)
Appellants contend that “one of skill in the art would understand that
‘backpeaks’ would refer to trimers and O-alkylated dimers and compounds
having longer retention times on reverse phase HPLC than iodixanol.”
(App. Br. 12.)
The issue with respect to this rejection is:
Whether the term “backpeak” renders claim 1 indefinite.
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Additional Findings of Fact
FF1. The Specification provides as follows:
The most important impurities in the reaction with regard
to work-up consequences are the so-called backpeaks. This term
refers to retention times in reversed phase HPLC, where the
backpeaks have slightly longer retention times than iodixanol
itself. Most of the backpeaks are either trimers or O-alkylated
dimers.
(Spec. 4, ll. 19-22; emphasis added.)
Principles of Law
Although words in a claim are generally given their ordinary
and customary meaning, a patentee may choose to be his own
lexicographer and use terms in a manner other than their
ordinary meaning, as long as the special definition of the term
is clearly stated in the patent specification or file history.

Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996).

Analysis
We agree with Appellants that the use of the term “backpeaks” does
not render the claims indefinite. The Specification clearly defines the term
in the context of reverse phase HPLC and in relation to other compounds.
(FF1.) Further, the claims require the intensity of the backpeaks to “not
exceed 2% at 55 - 60% conversion of Compound A to iodixanol.” (App. Br.
15.) Accordingly, we reverse the rejection of claims 1-4 under 35 U.S.C.
§ 112, second paragraph, as being vague and indefinite.
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Conclusion of Law
The term “backpeak” does not render claim 1 indefinite.

II. – IV.
We vacate the pending rejections under 35 U.S.C. § 103(a) and the
judicially-created doctrine of obviousness-type double patenting in favor of
the following new grounds of rejection.

NEW GROUNDS OF REJECTION
V.
Pursuant to our authority under 37 C.F.R. § 41.50(b), we enter a new
ground of rejection of all the claims on appeal under 35 U.S.C. § 103(a).
Claims 1-4 are rejected under 35 U.S.C. 103(a) as being unpatentable over
the combination of Homestad and Malthe-Sorenssen. Our reasons follow.

Additional Findings of Fact
FF2. “Compound A” as used by Homestad is 5-acetamido-N,N'-
bis(2,3-dihydroxypropyl)-2,4,6-triiodo-isophthalamide, which is likewise
referred to as Compound A in the Specification. (See e.g., Homestad,
Abstract; see also, Spec. 2, l. 1.)
FF3. Example 1 of Homestad provides as follows:
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Compound A (366 g) was dissolved in a solution of
NaOH(23 g) in 2-methoxyethanol (360 ml) at 50° C. The
temperature was decreased to 15° C. when all solids were
dissolved, and conc. HCl (28 g) was added to the solution.
Epichlorohydrin (13 g) was added in one portion, and the
reaction was monitored by HPLC. After 46 hours the content of
iodixanol in the reaction mixture was 49.6%. Water (575 ml)
was added, and the temperature was increased to 19° C. The
solution was at this time clear, so no further addition of sodium
hydroxide was necessary. The pH was adjusted to 10.8 by 18%
hydrochloric acid, and the solution seeded with 1 g of
Compound A. … The filtrate was further desalinated and
crystallised by conventional methods, providing iodixanol
suitable for pharmaceutical use.
(Homestad, col. 5, l. 59 to col. 6, l. 10., emphasis added.)
FF4. Homestad discloses as follows:
The dimerisation step itself may be carried out as
described in NO 161368 and WO 98/23296, for example using
epichlorohydrin, 1,3-dichloro-2-hydroxypropane or 1,3-
dibromo-2-hydroxypropane as the dimerisation agent. The
reaction is usually carried out in a non-aqueous solvent such as
a C1-6 alcohol, preferably 2-methoxyethanol or methanol, and
generally results in the conversion of 40-60% of Compound A
to iodixanol. Dimerisation in pure water or mixtures of water
and one or more alcohols (e.g. C1-6-alkanols) is also possible.
(Homestad, col. 4, ll. 37-46., emphasis added)
FF5. Homestad discloses as follows:
The pH of the solution is then adjusted to about 10-11 by
addition of an acid, e.g. hydrochloric acid, to provoke
precipitation of unreacted Compound A and if necessary the
temperature can be adjusted to 15-40 C., preferably 18-30 C.
(Homestad, col. 4, ll. 58-62.)
FF6. Example 1 of Malthe-Sorenssen discloses a process for the
synthesis of iodixanol from 5-acetamido-N,N'-bis(2,3-dihydroxypropyl)-
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2,4,6-triiodo-isophthalamide where the dimerization reaction with
epichlorohydrin is performed at pH 12 at 15° C. (Malthe-Sorenssen, col. 5,
ll. 56-65.)
FF7. Malthe-Sorenssen discloses that the amount of overalkylated
substances can be monitored with HPLC, where “overalkylated substances
have longer retention times than iodixanol itself on reversed phase HPLC
columns.” (Id. at col. 6, ll. 4-12.)
FF8. Malthe-Sorenssen discloses that “[n]ecessary actions during the
synthesis are taken based on the content of overalkylated substances in the
reaction mixture” such as “by addition of hydrochloric acid when a content
of overalkylated substances of 1.4% or more is detected.” (Id. at col. 7, l. 66
to col. 8, l. 4.)
FF9. Malthe-Sorenssen discloses a monitoring system or the
production of iodinated X-ray contrast agents such as iodixanol that allows
for “a more rapid response in process control, eg. in terms of changing
process conditions such as temperature, pressure and pH, controlling
addition of reagents, or terminating reactions at the optimal point.” (Id. at
col. 1, ll. 39-43; emphasis added.)
FF10. Example 1 of Malthe-Sorenssen discloses a process for the
synthesis of iodixanol from 5-acetamido-N,N'-bis(2,3-dihydroxypropyl)-
2,4,6-triiodo-isophthalamide using 2-methoxyethanol as solvent and in the
presence of epichlorohydrin. (Malthe-Sorenssen, col. 5, ll. 56-65.)
FF11. Regarding the selection of solvents, Malthe-Sorenssen
discloses as follows:
The solvent, co-solvents or anti-solvents may be any material
capable of functioning as solvents or anti-solvents, but
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preferably will be materials with as few peaks as possible in the
spectra being studied close to or overlapping with the peaks of
the compounds of interest. Examples include water, aliphatic
hydrocarbons, aromatic hydrocarbons, halogenated
hydrocarbons, alcohols, polyols, ketones, esters, ethers, nitrites,
DMSO, DMF, etc., eg. water, C1-4 alkanols, C2-6
alkoxyalkanols, C2-6 linear or cyclic ethers, C3-6 ketones, C2-6
esters, C4-10 hydrocarbons, C1-4 haloalkanes, etc.

(Malthe-Sorenssen, col. 4, ll. 54-64; emphasis added.)

Principles of Law
In KSR Int’l v. Teleflex Inc., 550 U.S. 398, 418 (2007), the Supreme
Court emphasized that “the [obviousness] analysis need not seek out precise
teachings directed to the specific subject matter of the challenged claim, for
a court can take account of the inferences and creative steps that a person of
ordinary skill in the art would employ.” In this regard, the obviousness
analysis permits reliance upon “common sense” or the knowledge of the
skilled artisan to bridge gaps in prior art’s explicit teachings. Id. at 420-21.
“[D]iscovery of an optimum value of a result effective variable in a
known process is ordinarily within the skill of the art.” In re Boesch, 617
F.2d 272, 276 (CCPA 1980) (citations omitted). However, a particular
parameter must first be recognized as a result effective variable before
optimization can be characterized as routine experimentation. In re Antonie,
559 F.2d 618, 621 (CCPA 1977).
“[W]here the general conditions of a claim are disclosed in the prior
art, it is not inventive to discover the optimum or workable ranges by routine
experimentation.” In re Aller, 220 F.2d 454, 456 (CCPA 1955).
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Analysis
Example 1 of Homestad discloses a process for the dimerization of
Compound A to produce iodixanol within the claimed temperature range of
about 10 to about 20 °C, within the solvent concentration range of about 0.8
to about 2.0 ml solvent per g Compound A, and within the concentration
range of epichlorohydrin of about 0.30 to about 0.36 mole equivalents of
epichlorohydrin relative to Compound A. (FF2-FF5; App. Br. 8-9.)
The process of Example 1 of Homestad differs from the claimed
process in that 1) 2-methoxyethanol is used as solvent instead of
propylenegycol, 2) the pH of 10.8 is outside the claimed range of between
11.5 and 12.0, and 3) the amount of backpeaks was not measured. (Id.)
Regarding the choice of solvent, Homestad discloses methanol or 2-
methoxyethanol as a preferred solvent. (FF4.) Malthe-Sorenssen discloses a
process for the synthesis of iodixanol from 5-acetamido-N,N'-bis(2,3-
dihydroxypropyl)-2,4,6-triiodo-isophthalamide using 2-methoxyethanol as
solvent and in the presence of epichlorohydrin. (FF10.) Malthe-Sorenssen
also provides a list of suitable solvents that includes C1-4 alcohols
(methanol), C2-6 alkoxyalkanols (2-methoxyethanol) and polyols (propylene
glycol). (FF11.) Hence, polyols such as propylene glycol were recognized
as an equivalent to C1-4 alcohols such as methanol and C2-6 alkoxyalkanols
such as 2-methoxyethanol as a solvents suitable for use in the dimerization
reaction of Compound A. Substituting one art recognized equivalent for
another is obvious. See KSR Int'l Co. v. Teleflex Inc., 550 U.S. at 416 (“The
combination of familiar elements according to known methods is likely to be
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obvious when it does no more than yield predictable results”); In re Fout,
675 F.2d 297, 301 (CCPA 1982).
With regard to pH, Malthe-Sorenssen discloses that pH may be
adjusted as necessary to reduce the amount of overalkylated substances
having longer retention times than iodixanol, referred to in Appellants’
claims as “backpeaks”. (Compare FF1, FF7, FF8; and Appellants’ claim 1.)
Malthe-Sorenssen thus identifies pH as a result-effective variable. The
determination of the optimum or workable ranges of result-effective
variables is normally obvious. See In re Antonie, 559 F.2d at 620.
Appellants have provided no evidence that the claimed range of pH reflects
anything more than “the predictable use of prior art elements according to
their established functions.” KSR, 550 U.S. at 419.
Finally, Malthe-Sorenssen discloses the monitoring of overalkylated
substances (i.e., backpeaks; compare FF1, FF7 and FF8), and suggest
monitoring the dimerization reaction of Compound A to maintain the level
of overalkylated substances to less than 1.4%. (FF8.) Malthe-Sorenssen
thus provides a method for the dimerization of Compound A that monitors
the dimerization reaction for less than 1.4% backpeaks and suggests that a
person of ordinary skill in the art would have had a reasonable expectation
of success in achieving the claimed range of backpeaks.
For the foregoing reasons we are not persuaded by Appellants’
contention regarding the alleged failure of Homestad or Malthe-Sorenssen to
suggest the use of propylene glycol as a “sole solvent system for the
dimerization of Compound A to iodixanol under specific reaction conditions
such that the backpeak amounts do not exceed 2% at 55 - 60% conversion of
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Compound A.” (App. Br. 9-10.) In addition, Appellants’ contentions fail to
persuasively address the combination of Homestad and Malthe-Sorenssen
set forth above. We find claims 1 and 2 to be unpatentable over the
combination of Homestad and Malthe-Sorenssen.
With regard to claims 3 and 4, it is well established that different
temperatures will generally not support the patentability of subject matter
encompassed by the prior art unless there is evidence indicating such
temperature is critical. See In re Aller, 220 F.2d 454, 456 (CCPA 1955)
(Claimed process which was performed at a temperature between 40° C and
80° C and an acid concentration between 25% and 70% was held to be prima
facie obvious over a reference process which differed from the claims only
in that the reference process was performed at a temperature of 100°C and
an acid concentration of 10%.) Here, Malthe-Sorenssen identifies
temperature as a variable to be controlled in the production of iodinated X-
ray contrast agents such as iodixanol and the evidence of record does not
support a finding that the claims temperature of 10° C is critical with regard
to the results to be achieved (i.e., backpeak impurity amounts that do not
exceed 2% at 55 - 60% conversion of Compound A to iodixanol). (FF9.)
Appellants contend that the references do not teach or suggest the
production of iodixanol “under [the] specific reaction conditions (i.e.,
temperature, pH and concentration).” (App. Br. 5.) While we recognize that
variables such as temperature and pH could interact in an unpredictable or
unexpected way to render the combination nonobvious, see KSR, 550 U.S. at
421, Appellants fail to establish through persuasive evidence or argument
that the interaction of the claimed variables suggested by the prior art is
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unpredictable or unexpected. Accordingly, we find the subject matter of
claims 3 and 4 obvious under 35 U.S.C. § 103(a) in view of the Homestad
and Malthe-Sorenssen.
Conclusion of Law
Claims 1-4 are obvious under 35 U.S.C. § 103(a) in view of the
Homestad and Malthe-Sorenssen.

VI.
Pursuant to our authority under 37 C.F.R. § 41.50(b), we enter a new
ground of rejection of all the claims on appeal on the grounds of the
judicially-created doctrine of obviousness-type double patenting. Claims 1-4
are rejected under the judicially-created doctrine of obviousness-type double
patenting as being unpatentable over claims 1-4 of copending Application
12/621,551 in view of the combination of Homestad and Malthe-Sorenssen.
Our reasons follow.
Principles of Law
“Obviousness-type double patenting is a judge-made doctrine that
prevents an extension of the patent right beyond the statutory time limit. It
requires rejection of an application claim when the claimed subject matter is
not patentably distinct from the subject matter claimed in a commonly
owned patent.” In re Berg, 140 F.3d 1428, 1431 (Fed. Cir. 1998).

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Analysis
Instant claims 1-4 compare to claims 1-4 of the ’551 as follows
(emphasis added):
Present Claims Application 12/621,551
1. Process for the dimerisation of 5-
acetamido-N,N'-bis(2,3-
dihydroxypropyl)-2,4,6-
triiodoisophthalamide (Compound
A)
1. Process for the dimerisation of 5-
acetamido-N,N'-bis(2,3-
dihydroxypropyl)-2,4,6-
triiodoisophthalamide (Compound
A)
in a temperature range of about 10
to about 20°C
in a temperature range of about 10
to about 20°C
using propylene glycol as solvent in
a concentration of about 0.8 to
about 1.3 ml solvent per g
Compound A
using methanol as solvent in a
concentration of about 0.8 to about
2.0 ml solvent per g Compound A
in the presence of about 0.3 to
about 0.4 mole equivalents of
epichlorohydrin relative to
Compound A, and
in the presence of about 0.30 to
about 0.36 mole equivalents of
epichlorohydrin relative to
Compound A, and
wherein the reaction solution has a
pH value of about 11.5 to about
12.0, and
wherein the reaction solution has a
pH value of about 11.5 to about
12.2, and
wherein the amount of backpeaks
does not exceed 2% at 55 - 60%
conversion of Compound A to
iodixanol.
wherein the amount of backpeaks
does not exceed 2% at 55 - 60%
conversion of Compound A to
iodixanol.

2. The process of Claim 1, wherein
said amount of backpeaks does not
exceed 1.4% at 55 - 60%
conversion of Compound A to
iodixanol.
2. The process of Claim 1, wherein
said amount of backpeaks does not
exceed 1.4% at 55 - 60%
conversion of Compound A to
iodixanol.

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Present Claims Application 12/621,551
3. The process of Claim 2, wherein
said temperature range is a
temperature of about 10°C to about
15°C.
3. The process of Claim 2, wherein
said temperature range is a
temperature of about 10°C.

4. The process of Claim 1, wherein
said temperature range is a
temperature of about 10°C to about
15°C.
4. The process of Claim 1, wherein
said temperature range is a
temperature of about 10°C

The claims of these applications differ in the recitation of the solvent
system to be used for the dimerization of Compound A, where the present
claims recite the use of propylene glycol and the claims of the ‘551
application recite the use of methanol. However, these claims are not
patentably distinct because C1-4 alcohols such as methanol and polyols such
as propylene glycol are art recognized equivalents suitable for use as
solvents in the dimerization reaction of Compound A. (FF4 and FF11.)
Specifically, Homestad discloses the use of methanol as a preferred solvent
in the dimerization of Compound A. (FF4.) Malthe-Sorenssen provides a
list of suitable solvents that includes C1-4 alcohols (methanol) and polyols
(propylene glycol). (FF11.) Substituting one art recognized equivalent for
another is obvious. See KSR Int'l Co. v. Teleflex Inc., 550 U.S. at 416 (“The
combination of familiar elements according to known methods is likely to be
obvious when it does no more than yield predictable results”); In re Fout,
675 F.2d 297, 301 (CCPA 1982). We therefore conclude that instant claims
1-4 are not patentably distinct from claims 1-4 of the ‘556 patent.
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Conclusion of Law
Claims 1-4 are rejected for obviousness-type double patenting.

VII.
Pursuant to our authority under 37 C.F.R. § 41.50(b), we enter a new
ground of rejection of all the claims on appeal on the grounds of the
judicially-created doctrine of obviousness-type double patenting. Claims
1-4 are rejected under the judicially-created doctrine of obviousness-type
double patenting as being unpatentable over claims 1-4 of copending
Application 12/621,571 in view of Malthe-Sorenssen and Cervenka. Our
reasons follow.
Additional Findings of Fact
FF12. Cervenka discloses “[a] process for the manufacture of
iodixanol by performing a purification process of the crude product in a
solvent comprising 1-methoxy-2-propanol.” (Cervenka, Abstract.)
FF13. Cervenka discloses that “[d]imerisation in pure water or
mixtures of water and one or more alcohols (e.g. C1-6-alkanols) or in a
solvent comprising 1-metoxy-2-propanol is also possible.” (Cervenka, ¶
[0018].)
FF14. Cervenka discloses as follows:
The water content and the amount of 1-metoxy-2-propanol
depend on the desired initial supersaturation with respect to
iodixanol. The range of 1-metoxy-2-propanol/water should be
approximately 1 to 20 g of 1-metoxy-2-propanol per g of water,
preferably 1 to 10 g of 1-metoxy-2-propanol per g of water,
more preferred 1 to 5 g of 1-metoxy-2-propanol per g of water
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and even more preferred 1.5 to 3 g of 1-metoxy-2-propanol per
g of water. Further, the range of 1-metoxy-2-propanol/crude
product should be approximately 0.2 to 4 g of 1-metoxy-2-
propanol per g of the crude product and preferably 0.3 to 2 g of
1-metoxy-2-propanol per g of the crude product.

(Cervenka, ¶ [0021].)
Analysis
Instant claims 1-4 compare to claims 1-4 of the ’571 as follows
(emphasis added):
Present Claims Application 12/621,571
1. Process for the dimerisation of 5-
acetamido-N,N'-bis(2,3-
dihydroxypropyl)-2,4,6-
triiodoisophthalamide (Compound
A)
1. Process for the dimerisation of 5-
acetamido-N,N'-bis(2,3-
dihydroxypropyl)-2,4,6-
triiodoisophthalamide (Compound
A)
in a temperature range of about 10
to about 20°C
in a temperature range of about
10°C to about 20°C
using propylene glycol as solvent in
a concentration of about 0.8 to
about 1.3 ml solvent per g
Compound A
using a solvent mixture comprising
about 70 to about 90 vol% l-
methoxy-2-propanol and about 10
to about 30 vol% water or methanol
in a concentration of about 0.8 to
about 2.0 ml solvent per g
Compound A
in the presence of about 0.3 to about
0.4 mole equivalents of
epichlorohydrin relative to
Compound A, and
in the presence of about 0.30 to
about 0.40 mole equivalents of
epichlorohydrin relative to
Compound A, and
wherein the reaction solution has a
pH value of about 11.5 to about
12.0, and

wherein the amount of backpeaks
does not exceed 2% at 55 - 60%
conversion of Compound A to
wherein the amount of backpeaks
does not exceed 2% at 55 - 60%
conversion of Compound A to
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Present Claims Application 12/621,571
iodixanol. iodixanol.

2. The process of Claim 1, wherein
said amount of backpeaks does not
exceed 1.4% at 55 - 60%
conversion of Compound A to
iodixanol.
2. The process of Claim 1, wherein
said amount of backpeaks does not
exceed 1.4% at 55 - 60%
conversion of Compound A to
iodixanol.

3. The process of Claim 2, wherein
said temperature range is a
temperature of about 10°C to about
15°C.
3. The process of Claim 2, wherein
said temperature range is a
temperature of about 10°C.

4. The process of Claim 1, wherein
said temperature range is a
temperature of about 10°C to about
15°C.
4. The process of Claim 1, wherein
said temperature range is a
temperature of about 10°C

The claims of these applications differ in the recitation of the solvent
system to be used for the dimerization of Compound A, where the present
claims recite the use of propylene glycol and the claims of the ‘571
application recite the use of a certain mixture comprising 1-methoxy-2-
propanol and water or methanol. However, these claims are not patentably
distinct because propylene glycol and the recited mixture comprising 1-
methoxy-2-propanol and water are art recognized equivalents suitable for
use as solvents in the production of iodixanol from Compound A. (FF11
and FF13-14.) Specifically, Malthe-Sorenssen provides a list of suitable
solvents that includes polyols, which encompasses propylene glycol.
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(FF11.) Cervenka discloses the use of a water and 1-methoxy-2-propanol as
solvents in the dimerization of Compound A (FF13) and the specific
mixtures recited in claim 1 of the present application are disclosed in
Cervenka in relation to the purification process of iodixanol (FF14).
It is prima facie obvious to combine two compositions
each of which is taught by the prior art to be useful for the same
purpose, in order to form a third composition which is to be
used for the very same purpose.... [T]he idea of combining
them flows logically from their having been individually taught
in the prior art.
In re Kerkhoven, 626 F.2d 846, 850 (CCPA 1980) (citations omitted). We
therefore, conclude that instant claims 1-4 are not patentably distinct from
claims 1-4 of the ‘571 patent.

Conclusion of Law
Claims 1-4 are rejected for obviousness-type double patenting.

SUMMARY
The rejection of claims 1-4 under 35 U.S.C. § 112, second paragraph,
is reversed.
The rejections of claims 1-4 under 35 U.S.C. § 103(a) as being
unpatentable over Hansen et al., Homestad, Malthe-Sorenssen or Cervenka
et al. are vacated.
The rejection of claims 1-4 under the judicially-created doctrine of
obviousness-type double patenting as being unpatentable over claims 1-4 of
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Application 12/621,556

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copending Application 12/621,571 in view of Hansen, Homestad, Malthe-
Sorenssen or Cervenka is vacated.
The rejection of claims 1-4 under the judicially-created doctrine of
obviousness-type double patenting as being unpatentable over claims 1-4 of
copending Application 12/621,556 in view of Hansen, Homestad, Malthe-
Sorenssen or Cervenka is vacated.
Claims 1-4 are rejected under 35 U.S.C. 103(a) as being unpatentable
over the combination of Homestad and Malthe-Sorenssen.
Claims 1-4 are rejected under the judicially-created doctrine of
obviousness-type double patenting as being unpatentable over claims 1-4 of
copending Application 12/621,551 in view of the combination of Homestad
and Malthe-Sorenssen.
Claims 1-4 are rejected under the judicially-created doctrine of
obviousness-type double patenting as being unpatentable over claims 1-4 of
copending Application 12/621,571 in view of Malthe-Sorenssen and
Cervenka.

TIME PERIOD FOR RESPONSE
This decision contains new grounds of rejection pursuant to 37 C.F.R.
§ 41.50(b), which provides that “[a] new ground of rejection . . . shall not be
considered final for judicial review.”
37 C.F.R. § 41.50(b) also provides that the Appellants, WITHIN
TWO MONTHS FROM THE DATE OF THE DECISION, must exercise
one of the following two options with respect to the new ground of rejection
to avoid termination of the appeal as to the rejected claims:
Appeal 201-001716
Application 12/621,556

20
(1) Reopen prosecution. Submit an appropriate amendment of the
claims so rejected or new evidence relating to the claims so rejected, or both,
and have the matter reconsidered by the Examiner, in which event the
proceeding will be remanded to the Examiner. . . .
(2) Request rehearing. Request that the proceeding be reheard under
§ 41.52 by the Board upon the same record. . . .
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

REVERSED-IN-PART, VACATED-IN-PART, 37 CFR § 41.50(b)

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