Ex Parte Lesch et al

Patent Trial and Appeal Board

Jul 25, 2017

12522646 (P.T.A.B. Jul. 25, 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.
12/522,646 07/09/2009 Hanna P. Lesch GB07/02695.8 2023
22925 7590 07/27/2017
PHARMACEUTICAL PATENT ATTORNEYS, LLC
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4THFLOOR
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EXAMINER
NGUYEN, QUANG
ART UNIT PAPER NUMBER
1633
NOTIFICATION DATE DELIVERY MODE
07/27/2017 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):
docket @ LicensingLaw. net
administration @LicensingLaw.net
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte HANNA P. LESCH, KARI J. AIRENNE, and
SEPPO YLA-HERTTUALA1
Appeal 2015-003488
Application 12/522,646
Technology Center 1600
Before DEMETRA J. MILLS, ERIC B. GRIMES, and JOHN E.
SCHNEIDER, Administrative Patent Judges.
GRIMES, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35U.S.C. § 134 involving claims to a method
of generating a lentivirus vector, which have been rejected based on new
matter and obviousness. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
STATEMENT OF THE CASE
“Lentiviruses, such as Human Immunodeficiency Virus I, are
promising tools for gene therapy due to their ability to transduce and
1 Appellants identify the Real Party in Interest as Ark Therapeutics Group,
pic. (Br. 4.)
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Application 12/522,646
integrate into the genome of both dividing and non-dividing cells.” (Spec.
1:6—8.) To improve the safety of producing replication-defective lentiviral
vectors, the “lentivirus genome can be separated into four plasmids.” (Id. at
1:8-13.)
“Baculoviruses possess several advantages for gene delivery
applications. They have a large insert capacity (> 100 kb) and are capable of
transducing most mammalian cell lines,... are easy to produce in large-
scale and high titers, and they present few safety problems as they are not
able to replicate in mammalian cells.” (Id. at 2:5—10.)
Claims 1—3 and 5—10 are on appeal. Claims 1, 7, and 8 are illustrative
and read as follows:
1. A method of generating a lentivirus vector, comprising
cloning each of a lentivirus transfer construct, gag, pol, a
nucleic acid coding for an an envelope protein and rev
respectively into the same baculovirus or different
baculoviruses, and transducing a producer cell with said same
baculovirus or said different baculoviruses.
7. The method of claim 1, said transducing performed using
a Multiplicity Of Infection (MOI) of not more than about 250.
8. The method of claim 7, said transducing performed using
a Multiplicity Of Infection (MOI) of not more than about 50.
The claims stand rejected as follows:
Claims 7—10 under 35 U.S.C. § 112, first paragraph, for lack of
adequate written description (Final Action2 3) and
2 Office Action mailed March 21, 2012.
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Claims 1—3 and 5—8 under 35 U.S.C. § 103(a) as obvious based on
Schauber,3 Leblois-Prehaud,4 and Kingsman5 (Final Action 7).
I
The Examiner has rejected claims 7—10 under 35 U.S.C. § 112, first
paragraph, on the basis that the Specification does not provide support for
the multiplicities of infection (MOIs) recited in claims 7—9 or the culture
times recited in claim 10. (Final Action 3—4.) The Examiner finds,
therefore, that the Specification’s description does not show that Appellants
had possession of the claimed methods at the time the application was filed.
(Id. at 5.)
We agree with the Examiner that claims 8—10 are not supported by an
adequate written description in the Specification. Claim 8, reproduced
above, requires an MOI of not more than about 50; claim 9 is similar but
requires an MOI of not more than about 125 for the transfer construct and
not more than about 25 for the other nucleic acids (Br. 27).
The Specification describes MOIs “between 50 and 1000 pfu per cell”
(Spec. 5:17); MOIs of 500, 750, 1000, 250, and 50 (id. at 7:8-16); “MOI
100 and 1000” (id. at 8:20); and MOI 50 (id. at 9:7). Thus, the lowest MOI
described in the Specification is 50.
Because the Specification fails to describe any MOI of less than 50,
we agree with the Examiner that the Specification does not show possession
of an MOI of “not more than about 50,” as recited in claim 8, or MOIs of
3 US 6,863,884 B2, issued Mar. 8, 2005
4 US 6,387,670 Bl, issued May 14, 2002
5 WO 98/55640, published Dec. 10, 1998
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“not more than about 25” for the gag,pol, envelope protein-encoding, and
rev nucleic acids, as recited in claim 9. See Ariad Pharms., Inc. v. Eli Lilly
& Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010) (“[T]he test for sufficiency [of
written description] is whether the disclosure of the application relied upon
reasonably conveys to those skilled in the art that the inventor had
possession of the claimed subject matter as of the filing date.”).
Appellants argue that “[t]he inventors teach that the ‘multiplicity of
infection’ (or ‘MOI’) functions opposite to what the artisan would have
expected: they found that lower MOIs generate higher yield. . . . The
inventors thus teach that MOI is a results-critical variable, and that it
functions opposite to what the prior art implies.” (Br. 8.) The issue with
respect to this rejection, however, is whether the Specification’s description
demonstrates possession of the claimed invention, not whether the observed
results would have been expected. This argument is therefore unpersuasive.
Appellants also argue that “the artisan could easily derive the claimed
ranges from the disclosure. Indeed, the skilled artisan would of necessity
have some minor variation in MOI.” {Id. at 10.)
We agree that, for the written description requirement, “the test for
sufficiency is whether the disclosure of the application relied upon
reasonably conveys to those skilled in the art that the inventor had
possession of the claimed subject matter as of the filing date.” Ariad
Pharms., Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010)
(emphasis added). Appellants’ Specification, however, does not describe
any MOIs lower than 50. It therefore does not reasonably convey to those
skilled in the art that Appellants had possession of an MOI of “not more than
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about 50,” as recited in claim 8, or MOIs of “not more than about 25” for the
gag, pol, envelope protein-encoding, and rev nucleic acids, as recited in
claim 9.
We also agree with the Examiner that the Specification does not
adequately describe the method of claim 10, which requires “culturing said
producer cell for at least about 144 hours post-transduction.” (Br. 27.) The
Specification describes collecting “[t]he cell supernatant containing
lentiviruses ... 48 h post transduction.” (Spec. 5:20-21; see also 7:5—6.)
We agree with the Examiner that a description of culturing producer cells for
48 hours post-transduction before collecting lentiviruses does not show
possession of a method of culturing producer cells for at least about 144
hours post-transduction, as required by claim 10.
Appellants argue that “the Specification’s Examples show actual
reductions to practice. Those Examples in fact produced cells which
survived for at least 144 hours post-transduction. The disclosure thus
supports the claimed limitation inherently.” (Br. 12—13.) Appellants do not,
however, point to any example in the Specification that describes culturing a
producer cell of at least about 144 hours post-transduction, and we find no
description in the Specification of culturing for more than 48 hours post­
transduction. Appellants have provided no other evidence to show that the
claimed method produces cells that survive for at least 144 hours, but in any
case “[t]he written description requirement requires possession as shown in
the specification, not as shown by prior experimental work.” Allergan, Inc.
v. Sandozlnc., 796 F.3d 1293, 1309 (Fed. Cir. 2015).
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However, we agree with Appellants that the method of claim 7, which
requires “transducing performed using a Multiplicity Of Infection (MOI) of
not more than about 250,” is adequately described in the Specification. As
discussed above, the Specification describes transducing cells using MOIs of
50, 100, and 250. (Spec. 7:8-16, 8:20, 9:7.)
“In order to satisfy the written description requirement, the disclosure
as originally filed does not have to provide in haec verba support for the
claimed subject matter at issue.” Purdue Pharma L.P. v. Faulding, Inc., 230
F.3d 1320, 1323 (Fed. Cir. 2000). Rather, section 112 “require[s] only
sufficient description to show one of skill in the [relevant] art that the
inventor possessed the claimed invention at the time of filing.” Union Oil
Co. of Cal. v. Atlantic Richfield Co., 208 F.3d 989, 997 (Fed. Cir. 2000).
Here, we agree with Appellants that the description of transducing cells at
MOIs of 50, 100, and 250 is adequate to show possession to those skilled in
the art of transducing at an MOI of not more than 250, as recited in claim 7.
We therefore affirm the rejection of claims 8—10 under 35 U.S.C.
§112, first paragraph, but reverse the rejection of claim 7 on that basis.
II
The Examiner has rejected claims 1—3 and 5—8 as obvious based on
Schauber, Leblois-Prehaud, and Kingsman. The Examiner finds that
Schauber discloses a lentiviral packaging system comprising
(i) a first vector comprising a gag, a pol, or gag and pol genes;
(ii) a second vector comprising a functionally modified or
heterologous envelope gene (including and not necessarily
limited to baculovirus envelope protein bp64 and VSV-G); and
(iii) a third vector comprising a rev gene; and a producer cell
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comprising the packaging system and a lentivrial [sic] transfer
vector comprising a transgene.
(Final Action 8, emphasis omitted.)
The Examiner finds that Schauber does not teach using baculovirases
as vectors but Leblois-Prehaud teaches a method of making a recombinant
virus “based on the use of one or more baculoviruses for providing the
complementary functions (e.g., gag, pol and/or env for the retrovirus . . .) for
the defective recombinant genome in competent host cells.” {Id., emphasis
omitted.) The Examiner also finds that Leblois-Prehaud teaches that using
baculoviruses as vectors provides several advantages. {Id. at 9.) The
Examiner finds that Kingsman likewise “taught at least the production of
retroviral particles, including HIV particles, in a baculovirus expression
system (see at least the abstract). Kingsman taught specifically expression
of HIV gag-pol, VSV-G and an HIV-based vector genome in a baculovirus
expression system.” {Id. at 9-10, emphasis omitted.)
The Examiner concludes that it would have been obvious to modify
Schauber’s method “by also at least cloning Gag/Pol, Rev, VSV[-]G and a
lentivirus transfer construct into at least 4 separate baculoviruses and
introducing the recombinant baculoviruses into a producer cell. . . , to
generate a lentivirus vector in light of the teachings of Leblois-Prehaud et al
and Kingsman.” {Id. at 10.) The Examiner finds that a skilled artisan would
have had a reason to combine the references because Leblois-Prehaud
discloses advantages of using baculovirus vectors for producing recombinant
viruses and Kingsman “taught specifically expression of HIV gag-pol, VSV-
G and an HIV-based vector genome in a baculovirus expression system.”
{Id.)
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We agree with the Examiner that claim 1 would have been obvious to
one of ordinary skill in the art based on the cited references. Schauber
discloses “a retroviral packaging system that comprises at least two vectors:
a first vector comprises a first nucleotide sequence comprising a gag, a pol,
or gag and pol genes; and a second vector comprises a second nucleotide
sequence comprising a heterologous or functionally modified envelope
gene.” (Schauber 3:6—11.) Schauber teaches that its system “provides an
alternative to pseudotyping retroviruses with VSV-G that offers broad
tropism but lacks the cytotoxicity associated with VSV-G.” {Id. at 3:3—5.)
VSV-G is an envelope glycoprotein. {Id. at 1:53—55, 2:55—57.)
Schauber also teaches a preferred embodiment in which “the system
further comprises a third nucleotide sequence that comprises a rev gene.”
{Id. at 3:17—18.) Schauber states that “[t]he invention further provides a
producer cell that comprises the packaging system of the invention and a
retroviral transfer vector comprising a transgene.” {Id. at 3:22—24.)
Schauber states:
Typically, the packaging vectors are included in a
packaging cell, and are introduced into the cell via transfection,
transduction or infection. Methods for transfection, transduction
or infection are well known by those of skill in the art. A
retroviral transfer vector of the present invention can be
introduced into a packaging cell line, via transfection,
transduction or infection, to generate a producer cell or cell line.
{Id. at 10:8—15, emphasis added.)
Thus, Schauber discloses vectors comprising each of the nucleic acids
recited in claim 1 and also suggests transducing them into a producer cell.
Schauber does not, however, disclose using baculoviruses as vectors in its
system.
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Leblois-Prehaud discloses that “[i]n the recombinant vectors derived
from retroviruses, the gag, pol and env genes are generally deleted,
completely or in part, and replaced by a heterologous nucleic acid sequence
of interest.” (Leblois-Prehaud 3:8—11.) “Given their defective character in
relation to the replication, the production of these various recombinant
viruses involves the possibility of transcomplementing the functions deleted
from the genome.” {Id. at 3:16—19.)
Leblois-Prehaud states that one “approach consists in cotransfecting
with the defective viral genome a construct (plasmid or adenovirus)
providing the complementation functions.” {Id. at 4:33—35.) Leblois-
Prehaud discloses “us[ing] either a baculovirus comprising all the functions
necessary for the transcomplementation of the defective recombinant
genome, or several baculoviruses each carrying one or more of the functions
necessary for the transcomplementation of the defective recombinant
genome.” {Id. at 5:10-15.)
Leblois-Prehaud states that “the advantages of the system of the
invention are numerous” and include lack of contamination of the viral
preparation with baculovirus (since the baculovirus does not replicate in
human cells), the large cloning capacity of baculovirus vectors, and the
advanced development of baculovirus technology. {Id. at 5:23—30, 5:66 to
6:3.) Leblois-Prehaud teaches that its system can be used to make
recombinant retroviruses. {Id. at 7:32—38, 8:66 to 9:10.)
Kingsman states that, in methods for making retroviral vectors,
“[pjrotein that is required for the assembly of new virus particles and for
enzyme and regulatory functions can be produced by non-genome sequences
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in, for example, a mammalian packaging cell line” and a “genome sequence
lacking the protein encoding functions is provided, so that the resulting
retroviral vector particles are capable of infecting but not replicating.”
(Kingsman 9:19—26.) Kingsman discloses that “functional retroviral vector
particles can be produced in a baculovirus expression system and those
particles can successfully deliver one or more NOI(s) [nucleotide
sequence(s) of interest] to target cells.” {Id. at 17:11—13.)
We agree with the Examiner that, based on the disclosures of
Schauber, Leblois-Prehaud, and Kingsman, the method of claim 1 would
have been obvious to a person of ordinary skill in the art. Specifically,
Schauber teaches a system and method that includes all of the limitations of
claim 1 except for the use of baculoviruses as vectors. Leblois-Prehaud,
however, suggests using baculovirus vectors to make recombinant retroviral
vectors and Kingsman expressly describes making retroviral vectors using a
baculovirus expression system. Thus, it would have been obvious, based on
Leblois-Prehaud and Kingsman, to modify Schauber’s method by using
baculovirus vectors to express the components of Schauber’s system.
Leblois-Prehaud provides a reason to make this modification to
Schauber, because Leblois-Prehaud discloses that baculovirus vectors have
numerous advantages, including the lack of contamination of the viral
preparation with baculovirus, the large cloning capacity of baculovirus
vectors, and the advanced development of baculovirus technology. The
cited references therefore support a prima facie case of obviousness.
Appellants argue that “Leblois stridently admonishes to avoid
Schauber for several reasons.” (Br. 19.) Specifically, Appellants argue that
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“Schauber teaches to use (and the instant claims require) gag, pol and env.
In contrast, . . . Leblois says, ‘In the recombinant vectors derived from
retroviruses, the gag, pol and env genes are generally deleted.’” (Id.)
This argument is unpersuasive. The section quoted by Appellants
refers to the retroviral vectors that contain a transgene. The full sentence
reads: “In the recombinant vectors derived from retroviruses, the gag, pol
and env genes are generally deleted, completely or in part, and replaced by a
heterologous nucleic acid sequence of interest.” (Leblois-Prehaud 3:8—11.)
Leblois-Prehaud goes on to say that, because the recombinant vectors lack
gag, pol, and env, “the production of these various recombinant viruses
involves the possibility of transcomplementing the functions deleted from
the genome.” (Id. at 3:16—19.) Thus, Leblois-Prehaud also requires
production of gag, pol, and env to generate retroviral vectors.
Appellants also argue that “Schauber (and the instant inventors) teach
using 293 and similar ‘encapsidation’ cell lines as producer cells. Leblois
teaches away from this.” (Br. 20.) Specifically, Appellants argue that
“Leblois warns that Schauber’s encapsidation cells ‘hardly make it possible
to avoid the production of replicative contaminant viruses’ which are not
only ‘contaminant’ (unwanted) but are also ‘replicative[.]’” (Id.)
Appellants argue that, “[furthermore, Leblois complains Schauber’s cell
lines ‘do not allow ... in a satisfactory manner for an industrial use, very
highly defective viral genomes’” and “Leblois complains that Schauber’s
cell lines do not enable one to ‘obtain very high recombinant retrovirus
titres.’” (Id. at 20—21.)
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This argument is also unpersuasive. Leblois-Prehaud states that
“[t]wo approaches have been developed” to provide the functions (e.g., gag,
pol, and env) that have been deleted from recombinant retroviruses: “The
first is based on the construction of transcomplementing lines, that is to say
encapsidation lines. The second is based on the use of helper adenoviruses
or of helper plasmids.” (Leblois-Prehaud 3:23—26.) “[EJncapsidation lines
. . . comprise, integrated into their genome, the region(s) deleted from the
viral genome (El, E2 and/or E4 for example for the adenovirus; gag, pol
and/or env for the retrovirus . . .).” (Id. at 3:27—32.) It is these
encapsidation lines containing integrated retroviral genes to which Leblois-
Prehaud refers in the passages quoted by Appellants.
Leblois-Prehaud states that its system “overcome[s] these
disadvantages” because it “is based on the use of a baculovirus to provide
the complementation functions.” (Id. at 4:53—56.) Far from teaching away
from using 293 cells in its method, Leblois-Prehaud states that its process
“may be carried out in various types of cells,” and “[tjhere may be
mentioned, by way of nonlimiting example, the cells 293.” (Id. at 15:66—67,
16:15—16.) Appellants’ argument is therefore not supported by the evidence.
Appellants also argue that, while Leblois-Prehaud teaches cloning
“complementation functions” into baculoviruses, those complementation
functions are the rep and cap genes, while the “claimed invention requires
cloning a transfer construct into a baculovirus.” (Br. 21—22.) Appellants
argue that “Leblois pointedly does not teach cloning transfer construct into
baculovirus” and “suggests that baculovirus (an insect virus) would not be
able to successfully transfect with a human transfer construct.” (Id. at 22.)
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This argument is also unsupported by the evidence, and is therefore
unpersuasive. Leblois-Prehaud states that “the applicant has shown that it
was possible, with a recombinant baculovirus, to infect cells of human
origin,” that its process “may be carried out in various types of cells,” and
“[i]t is preferably a mammalian cell, still more preferably a cell of human
origin.” (Leblois-Prehaud 5:55—56, 15:66—67, 16:6—7.) Leblois-Prehaud
thus expressly suggests using baculovirus vectors in human cells. In view of
these disclosures, a person of ordinary skill in the art would have had a
reasonable expectation of success in using Leblois-Prehaud’s baculovirus
vectors in Schauber’s method—which includes a transfer vector—even in
human cells.
Appellants argue that “Schauber teaches that such systems generate
low yield because the inventors’ VSV-G is cytotoxic.” (Br. 23.) This
argument is unpersuasive because Schauber teaches that VSV-G “has been
used extensively for pseudotyping retroviral vectors, including lentiviral
vectors” and its use “has been attractive because of its high infectious titer
and physical stability” as well as its broad tropism. (Schauber 1:53—55,
2:43^46.) Thus, Schauber’s disclosure shows that VSV-G was an envelope
protein that was routinely used in retroviral vectors, and a skilled artisan
therefore would have considered it an obvious choice. “The combination of
familiar elements according to known methods is likely to be obvious when
it does no more than yield predictable results.” KSR Int’l Co. v. Teleflex
Inc., 550 U.S. 398,416 (2007).
Appellants argue that Kingsman teaches “using as producer cells
insect cells, rather than Schauber's human cells. . . . Kingsman cannot be
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combined with Schauber because Kingsman says that Schauber’s human
cells do not work.” (Br. 23.)
This argument is unpersuasive because, as discussed above, Leblois-
Prehaud expressly suggests using baculovirus vectors in human cells. The
rejection is based on all three references in combination, and each of their
teachings must be considered in the context of the other references. See In
re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986) (Each reference
“must be read, not in isolation, but for what it fairly teaches in combination
with the prior art as a whole.”).
Appellants also argue that “[cjombining Kingsman’s insect producer
cells with Leblois’ baculovirus bearing rep and cap ‘complementary
functions’” would not yield the claimed invention. (Br. 24.)
This argument is also unpersuasive because the rejection is based on
combining Leblois-Prehaud’s baculovirus vectors with the complementation
functions and transfer vector disclosed by Schauber and, as discussed above,
Leblois-Prehaud expressly suggests using its baculovirus vectors in human
cells. Appellants’ argument is based on a different combination of prior art
teachings than what is relied on by the Examiner.
With regard to secondary considerations, Appellants argue that the
claimed method differs from Schauber’s method in several ways: it uses
transduction rather than other methods to introduce foreign nucleic acids
into a cell; it works with one vector while Schauber’s method requires three
vectors; and it uses one transformation step while Schauber’s method
requires two. (Br. 16.) Appellants argue that “[tjhese apparently minor
changes in transformation method, vector number and transformation steps,
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when done together, appear synergistic: one of the inventors noted that with
the claimed method, yield ‘is 300 000 x more than the current process.’”
{Id. at 17, citing the Lesch Declaration.6)
This argument is unpersuasive. First, Schauber includes an example
in which “pseudotyped HIV vector particles were prepared and tested for
their ability to transduce three human cell lines,” including 293T cells.
(Schauber 29:11—13, 19.) Thus, Schauber’s method includes the
transduction limitation recited in claim 1.
In addition, claim 1 is not limited to a single baculovirus vector, but
encompasses cloning the recited nucleic acids into “the same baculovirus or
different baculoviruses.” Nor is the claimed method limited to only a single
transduction step; it simply requires “transducing a producer cell with said
same baculovirus or said different baculoviruses,” regardless of how many
transduction steps are carried out.
Finally, the Lesch Declaration does not purport to compare the
claimed process to Schauber’s process but rather describes the use of 293T
cells in suspension using roller bottles to produce lentiviral vectors. (Lesch
Decl. 110.) Dr. Lesch states that:
In roller bottles LV [lentivirus] titers were 2,2x106 TU/ml in
medium, when cell density in 60 ml was 4 x 106 cells/ml. Based
on these results we can estimate that the productivity in one wave
bioreactor batch would be (4 x 106 cells/ml) x (2,2x106 TlJ/ml) x
10000 ml = 8,8 x 1016 TU / one batch. This is 300 000 x more
than the current process for animal experiments using adherent
cells and plasmids.
6 Declaration under 37 C.F.R. § 1.132 of Hanna Pirita Lesch, filed July 21,
2011.
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(Lesch Decl. 111.)
Thus, the “unexpected results” pointed to by Appellants in the Brief
do not represent the results of an experiment that was actually carried out,
but a calculation based on hypothetically scaling up the experiment carried
out in roller bottles to a 10 liter bioreactor. “[I]t is well settled that
unexpected results must be established by factual evidence. ‘Mere argument
or conclusory statements in the specification does not suffice.’” In re
Geisler, 116 F.3d 1465, 1470 (Fed. Cir. 1997). In addition, the Lesch
Declaration compares these hypothetical results to “the current process for
animal experiments using adherent cells and plasmids,” not to the closest
prior art of Schauber. Appellants’ argument based on unexpected results is
therefore unpersuasive.
Regarding claim 2, Appellants argue that Schauber “alleges that VSV-
G is cytotoxic to producer cells, thus lowering producer cell yield. Schauber
. . . thus proposes eliminating VSV-G (replacing it with a baculoviral env
gene). In contrast, Claim 2 literally requires VSV-G envelope protein.” (Br.
17-18.)
This argument is unpersuasive because, as discussed above, Schauber
teaches that VSV-G was routinely used in retroviral, including lentiviral,
vectors and was known to have the advantages of high infectivity, physical
stability, and broad tropism. (Schauber 1:53—55, 2:13—16.) Thus, VSV-G
would have been an obvious choice to use as the envelope protein in
retroviral vectors. “The combination of familiar elements according to
known methods is likely to be obvious when it does no more than yield
predictable results.” KSR, 550 U.S. at 416.
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Claims 3 and 5—8 have not been argued separately and therefore fall
with claim 1. 37 C.F.R. § 41.37(c)(l)(iv).
SUMMARY
We affirm the rejection of claims 8—10 under 35 U.S.C. § 112, first
paragraph, but reverse this rejection as it applies to claim 7.
We affirm the rejection of claims 1—3 and 5—8 under 35 U.S.C.
§ 103(a) based on Schauber, Leblois-Prehaud, and Kingsman.
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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