Ex Parte TAKAHASHI et al

Patent Trials and Appeals Board

May 20, 2019

13408642 - (D) (P.T.A.B. May. 20, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/408,642 02/29/2012
23460 7590 05/22/2019
LEYDIG VOIT & MA YER, LTD
TWO PRUDENTIAL PLAZA, SUITE 4900
180 NORTH STETSON A VENUE
CHICAGO, IL 60601-6731
FIRST NAMED INVENTOR
Masaya TAKAHASHI
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
709964 7463
EXAMINER
BOWERS, ERIN M
ART UNIT PAPER NUMBER
1653
NOTIFICATION DATE DELIVERY MODE
05/22/2019 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):
Chgpatent@leydig.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MASA YO TAKAHASHI,
SATOSHI OKAMOTO, and NORIKO SAKAI
Appeal2017-010371
Application 13/408,642 1
Technology Center 1600
Before DONALD E. ADAMS, JOHN G. NEW, and RYAN H. FLAX,
Administrative Patent Judges.
ADAMS, Administrative Patent Judge.
DECISION ON APPEAL
This Appeal under 35 U.S.C. § 134(a) involves claims 1-6 and 9 (see
App. Br. 1). Examiner entered rejections under 35 U.S.C. § 103(a). We
have jurisdiction under 35 U.S.C. § 6(b ).
We REVERSE.
1 Appellants identify "RIKEN" as the real party in interest (Appellants'
Corrected Appeal Brief (App. Br.) 1 ).
Appeal2017-010371
Application 13/408,642
STATEMENT OF THE CASE
Appellants' disclosure "relates to a method of producing a retinal
pigment epithelial [ (RPE)2] cell from a human pluripotent stem cell, and a
medical use of a ... [RPE] cell obtainable by said production method"
(Spec. 1 ). Appellants' only independent claim, claim 1, is representative and
reproduced below:
1. A method of producing a retinal pigment epithelial cell
from a human pluripotent stem cell, which comprises
(a) a step of providing isolated human pluripotent stem cells,
wherein the isolated human pluripotent stem cells are dispersed
by a cell dissociation solution,
(b) a step of inducing differentiation of the isolated human
pluripotent stem cells into pigment cells by adhesion cultivation
of the isolated and dispersed human pluripotent stem cells of
step (a) in a medium containing a Nodal signal inhibitor and a
Wnt signal inhibitor at a concentration sufficient to induce
differentiation of the human pluripotent stem cells into pigment
cells in the absence of feeder cells to yield a culture containing
the pigment cells,
( c) a step of subjecting the obtained culture of step (b) to
further adhesion culture to yield a culture containing a pigment
cell colony, and
( d) a step of isolating the pigment cell from the obtained
culture of step ( c) and culturing the cell to yield the retinal
pigment epithelial cell.
(App. Br. 11.)
2 Appellants define the acronym RPE as retinal pigment epithelium. See
Appellants' June 22, 2012 Specification (Spec.) 7: 19-20 ("[t]he retinal
pigment epithelium (RPE) cell is an epithelial cell constituting the retinal
pigment epithelium"); see also Takahashi defined the acronym RPE as
retinal pigment epithelium (Takahashi ,r 17; see also Malcuit 1: 11-12
("retinal pigment epithelium (RPE) is the pigmented cell layer just outside
the neurosensory retina.")).
2
Appeal2017-010371
Application 13/408,642
Grounds of rejection before this Panel for review:
I. Claims 1-5 and 9 stand rejected under 35 U.S.C. § I03(a) as
unpatentable over the combination of Takahashi 3 and Kawasaki. 4
II. Claims 1---6 and 9 stand rejected under 35 U.S.C. § I03(a) as
unpatentable over the combination of Takahashi, Kawasaki, and Malcuit. 5
ISSUE
Does the preponderance of evidence relied upon by Examiner support
a conclusion of obviousness?
FACTUAL FINDINGS (FF)
FF 1. Takahashi discloses a method particularly suitable "for producing
retinal progenitor cells from embryonic stem [(ES) 6] cells of a rodent such as
a mouse," wherein "differentiation from [ES] ... cells to retinal progenitor
cells [is performed] particularly efficiently, [in] suspension culture ... in a
medium containing serum, a Nodal signal inhibitor, a Wnt inhibitor and
activin" (Takahashi ,r 73; 7 see id. ,r 46 (Takahashi "provides a method of
producing retinal progenitor cells from ... [ES] cells ... compris[ing]
culturing ... [ES] cells as suspended aggregates in a medium containing or
not containing serum, and obtaining retinal progenitor cells from the
culture"); id. ,r 1 (Takahashi "relates to a method of producing retinal
3 Takahashi et al., US 2010/0105137 Al, published Apr. 29, 2010.
4 Hiroshi Kawasaki et al., Generation of dopaminergic neurons and
pigmented epithelia from primate ES cells by stromal cell-derived inducing
activity, 99 PNAS 1580-85 (2002).
5 Malcuit et al., WO 2009/051671 Al, published Apr. 23, 2009.
6 The acronym ES refers to embryonic stem (see Takahashi ,r 3).
7 Takahashi discloses the use of serum-free media "for producing retinal
progenitor cells from [ES] ... cells of a primate such as a human or
monkey" (Takahashi ,r 74).
3
Appeal2017-010371
Application 13/408,642
progenitor cells, photoreceptor precursors, photoreceptors and the like"); id.
,r 132 (Takahashi discloses the use of suspension cell culture of ES cells to
produce a homogeneous population of, inter alia, retinal progenitor cells);
id. ,r 162 ( exemplifying the suspension culture of ES cells in differentiation
medium); see also id. ,r 50 (Takahashi discloses that "[w]hen [ES] ... cells
are suspension-cultured, to facilitate the formation of suspended aggregates,
and/ or to achieve efficient induction of differentiation, the culture is
preferably performed in the absence of feeder cells")).
FF 2. Takahashi discloses that "[a]fter the suspension culture, the
aggregates may be allowed to stand as they are, or subjected to a dispersing
treatment ... and ... further cultured under adhesive conditions" (Takahashi
,r 81; see also id. ,r 82 ("[t]he period of the adhesion culture can be of a
length that allows retinal progenitor cells to be produced more efficiently")).
FF 3. Takahashi discloses "a method of producing ... [RPE] cells[] [i]n
the same manner as ... described [ for the] method of producing retinal
progenitor cells, by culturing ... [ES] cells as suspended aggregates in a
medium containing or not containing serum, further culturing the cultured
cells under adhesive conditions, and obtaining ... [RPE] cells from the
culture" (Takahashi ,r 87; see FF 1-2; see also Takahashi ,r 135 ("[a]ny
method of cell separation and purification in public knowledge can be
used")).
FF 4. Examiner finds that "Takahashi does not teach that the
differentiation of [ES] ... cells into [RPE] ... cells was performed during
adhesion culture" or "a step of isolating the pigment cell from the obtained
culture and culturing the cell" and relies on Kawasaki to disclose "the
differentiation of primate [ES] ... cells into [RPE] ... cells by adhesion
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Appeal2017-010371
Application 13/408,642
culture on feeder cells" (Ans. 5 (citing Kawasaki 1583 (right col., second
para.)); see also Ans. 10 ("Kawasaki teaches that adhesion culture of primate
[ES] ... cells into [RPE] ... cells is possible in the presence of feeder cells"
( emphasis added))).
FF 5. Kawasaki discloses:
One unexpected finding from the primate study was the
appearance of epithelial cells with massive pigmentation, which
was rarely observed in SDIA-treated mouse ES cells or in
primate ES cells cultured on the collagen-coated dish
(unpublished observations). After culture on PA6 [feeder] cells
for 3 weeks, large patches of pigmented cells were present in 8
± 4% of the primate ES cell colonies ... and grew at a constant
rate on the feeder cells.
(Kawasaki 1583 (right col., second para.) (emphasis added).)
FF 6. Examiner finds that the combination of Takahashi and Kawasaki
fails to suggest "the step of isolating the pigment cell and culturing the cell
to yield the retinal pigment epithelial cell comprises subjecting the culture to
floating culture, isolating the pigment cell from the floating aggregate,
subjecting the pigment cell to adhesion culture, and selectively passaging the
cells" as required by Appellants' claim 6 and relies on Malcuit to make up
for this deficiency in the combination of Takahashi and Kawasaki (Ans. 7
(citing Malcuit 2:5-7, 51:12-52:3)).
ANALYSIS
Re} ection I:
Based on the combination of Takahashi and Kawasaki, Examiner
concludes that, at the time Appellants' invention was made, it would have
been prima facie obvious to produce a RPE cell from a human pluripotent
stem cell by adhesion culturing the human pluripotent stem cell on feeder
cells (see Ans. 5). We are not persuaded.
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Appeal2017-010371
Application 13/408,642
As Examiner appreciates "Takahashi does not teach that the
differentiation of [ES] ... cells into [RPE] ... cells was performed during
adhesion culture" and Kawasaki, as relied upon by Examiner, discloses
adhesion culturing ES cells on feeder cells (FF 4--5; see also App. Br. 5-7).
Thus, the combination of Takahashi and Kawasaki fails to suggest a method
wherein differentiation of a human pluripotent stem cells into a RPE cell is
induced by, inter alia, adhesion culturing the human pluripotent stem cell in
the absence of feeder cells as is required by Appellants' claimed invention
(see App. Br. 11 ).
We are not persuaded by Examiner's unsupported assertion that the
addition of Takahashi's Wnt and Nodal inhibitors to ES cells adherently
cultured in the absence of feeder cells will necessarily result in the
differentiation of ES cells into RPE (see Ans. 10-11; see also id. at 13-14).
As Appellants explain, Takahashi "does not teach or suggest that addition of
one or both of these inhibitors can be applied to a culture method other than
suspension culture" or "the induction of differentiation by adhesion culture
in the presence of a Nodal signal inhibitor and a Wnt signal inhibitor"
(Reply Br. 3). Simply stated, Examiner failed to establish an evidentiary
basis on this record to support a conclusion of obviousness. See In re Kahn,
441 F.3d 977, 988 (Fed. Cir. 2006) ("[R]ejections on obviousness grounds
cannot be sustained by mere conclusory statements; instead, there must be
some articulated reasoning with some rational underpinning to support the
legal conclusion of obviousness.").
Because Examiner failed to establish an evidentiary basis on this
record to support a conclusion of obviousness, we do not address
Appellants' "Objective Evidence ofNonobviousness" (see App. Br. 8-9
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Appeal2017-010371
Application 13/408,642
(emphasis omitted)). For the same reason we do not address the Ikeda or
Osakada references relied upon by Appellants to establish non-obviousness
(see App. Br. 7-9; Reply Br. 2).
Re} ection II:
Based on the combination of Takahashi, Kawasaki, and Malcuit,
Examiner concludes that, at the time Appellants' invention was made, it
would have been prima facie obvious to utilize the method suggested by the
combination of Takahashi and Kawasaki to produce RPE cells from ES cells
and then utilize Malcuit's dissociation and isolation methodology to produce
a pure culture of mature RPE cells (Ans. 8). We are not persuaded.
Examiner failed to establish that Malcuit makes up for the deficiency
in the combination of Takahashi and Kawasaki discussed above (see
generally App. Br. 8; Reply Br. 4).
CONCLUSION
The preponderance of evidence relied upon by Examiner fails to
support a conclusion of obviousness.
The rejection of claims 1-5 and 9 (Rejection I) under 35 U.S.C.
§ 103(a) as unpatentable over the combination of Takahashi and Kawasaki is
reversed.
The rejection of claims 1---6 and 9 (Rejection II) under 35 U.S.C.
§ 103(a) as unpatentable over the combination of Takahashi, Kawasaki, and
Malcuit is reversed.
REVERSED
7