Astellas Us LLC, Astellas Pharma Us, Inc., Gilead Sciences, Inc. v. Hospira, Inc.

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
ASTELLAS US LLC, ASTELLAS PHARMA US, INC.,
GILEAD SCIENCES, INC.,
Plaintiffs-Appellants
v.
HOSPIRA, INC.,
Defendant-Appellee
______________________
2022-1878
______________________
Appeal from the United States District Court for the
District of Delaware in No. 1:18-cv-01675-CFC-CJB, Chief
Judge Colm F. Connolly.
______________________
Decided: December 30, 2022
______________________
P AUL WHITFIELD HUGHES , McDermott Will & Emery
LLP, Washington, DC, argued for all plaintiffs-appellants.
Plaintiffs-appellants Astellas US LLC, Astellas Pharma
US, Inc. also represented by I AN BARNETT BROOKS ; J ASON
ALBERT L EONARD, New York, NY.
W. CHAD SHEAR, Fish & Richardson P.C., San Diego,
CA, for plaintiff-appellant Gilead Sciences, Inc. Also rep-
resented by ELIZABETH M. F LANAGAN, Minneapolis, MN;
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ASTELLAS US LLC v. HOSPIRA, INC. 2
ROBERT M. O AKES , Wilmington, DE; L ISA M. F ERRI,
MANUEL J OSE VELEZ, Mayer Brown, LLP, New York, NY.
CHARLES B. K LEIN, Winston & Strawn LLP, Washing-
ton, DC, argued for defendant-appellee. Also represented
by CLAIRE A. F UNDAKOWSKI, J OVIAL WONG; ALISON
MICHELLE K ING, Chicago, IL.
______________________
Before D YK, REYNA, and CUNNINGHAM , Circuit Judges.
D YK, Circuit Judge
Gilead Sciences, Inc., Astellas US LLC, and Astellas
Pharma US, Inc. (together, “Astellas”) sued Hospira, Inc.,
alleging that Hospira’s abbreviated new drug application
(“ANDA”) infringed three patents that cover Form A re-
gadenoson (U.S. Patent Nos. 8,106,183; RE47,301; and
8,524,883), a monohydrate (hydrate that contains one mol-
ecule of water in the crystal lattice for every molecule of the
compound) form of regadenoson that can be used to in-
crease blood flow to mimic a cardiac stress test. Astellas’s
theory was not that Hospira intentionally created Form A
regadenoson, but that this occurred inadvertently in the
production process for an intermediate product made by a
third party and incorporated by Hospira into its final prod-
uct. Before trial, Hospira amended its ANDA, allegedly
making it more difficult for Astellas to prove its original
infringement theory. Astellas then sought to present a new
and previously unasserted infringement theory (that Hos-
pira’s own process created Form A regadenoson).
The district court found this new theory to be untimely
and granted Hospira’s motion to strike the new infringe-
ment contentions and the related expert evidence. The
trial went forward on Astellas’s original infringement the-
ory, updated with supplemental evidence, and the district
court found that Hospira did not infringe. Astellas appeals
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ASTELLAS US LLC v. HOSPIRA, INC. 3
only the district court’s exclusion of the new theory. We
hold that the district court did not abuse its discretion in
excluding the new infringement theory, and we affirm.
B ACKGROUND
This case concerns U.S. Patent Nos. 8,106,183;
RE47,301; and 8,524,883 (the “Form A patents”), all of
which are owned by Astellas. The asserted patent claims
all recite, or depend from independent claims that recite,
Form A regadenoson, the most stable and only known mon-
ohydrate crystalline form of regadenoson.1
Hospira, Inc. is one generic manufacturer that filed an
ANDA with a paragraph IV certification for a generic drug
product with Form G regadenoson as the active pharma-
ceutical ingredient (“API”), a compound not covered by the
asserted patents. Hospira bought its API from Curia Mis-
souri, Inc. (“Curia”), formerly Euticals, Inc.,2 meaning Hos-
pira’s ANDA relied on and incorporated Curia’s Drug
Master File (“DMF”). A DMF is a confidential submission
to the FDA that provides detailed information about the
processes used to manufacture a drug. Curia created the
API by converting crude regadenoson to Form F re-
gadenoson (also not covered by the asserted patents) and
then to Form G regadenoson. However, when these forms
“are exposed to a sufficient amount of water, including wa-
ter in the air (i.e., humidity) and in reagents, they will con-
vert to Form A.” J.A. 176. Hospira and Curia were aware
of the risk of conversion and wanted to avoid conversion
during Curia’s manufacturing process.
1 Astellas owned other regadenoson patents covering
a broader array of regadenoson compounds and structures.
The last of these patents expired April 10, 2022.
2 Because the distinction is immaterial, Euticals,
Inc. will also be referred to as “Curia.”
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ASTELLAS US LLC v. HOSPIRA, INC. 4
Hospira’s ANDA product is created by a compounding
process in which Curia’s intermediate Form G product is
dissolved in a water-based solution. Again, there is a risk
that water exposure could cause Form G regadenoson to
convert to Form A regadenoson. However, Hospira claims
that the introduction of water during the compounding pro-
cess does not cause conversion to Form A regadenoson be-
cause Form G dissolves directly in the compounding
solution.
This case involves two separate infringement theories
provided by Astellas. The first is the intermediate theory
which is that the Form A patents are infringed because
Form A regadenoson is created during the manufacturing
of the Form G intermediate by Curia. The second is the
compounding theory which is that infringement of the
Form A patents occurs when the Form G intermediate con-
verts to Form A regadenoson during Hospira’s own com-
pounding process.
On June 30, 2020, shortly after Astellas was notified
that Hospira filed its ANDA, Astellas sued Hospira for in-
fringement of the Form A patents in the District of Dela-
ware, and the case was consolidated with similar cases
Astellas had brought against Apotex, Inc. and other generic
manufacturers who had filed their own ANDAs. The AN-
DAs were filed with a paragraph IV certification, which
stated that the listed patents, the Form A patents in this
case, are “invalid or will not be infringed by the manufac-
ture, use, or sale of the [generic] drug . . . .” 21 U.S.C. §
355(j)(2)(A)(vii)(IV); see also 35 U.S.C. § 271(e)(2)(A). As-
tellas’s theory was that these filings were acts of infringe-
ment.
Proving infringement requires showing that the ANDA
product proposed to be sold under the ANDA would in-
fringe. Astellas’s original infringement theory as to Hos-
pira was the intermediate theory which was, as the district
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ASTELLAS US LLC v. HOSPIRA, INC. 5
court found, “that crude and Forms F and G regadenoson
have ‘a propensity’ to convert to Form A when exposed to
water, and that water is introduced into Curia’s . . . manu-
facturing process.” J.A. 225. During discovery, Astellas’s
expert specifically disclaimed any theory that infringement
occurred during Hospira’s compounding process. See J.A.
1107.
During the pendency of the infringement action, Curia
amended its DMF to “optimize its manufacturing process
to limit the presence of water.” J.A. 186 (internal quota-
tion, alteration, and citations omitted). Hospira amended
its ANDA with the only change being to incorporate the
changes made by Curia. After Hospira amended its ANDA,
the district court entered the order at issue here establish-
ing supplemental fact discovery, supplemental expert dis-
covery, and infringement contentions regarding Hospira’s
amended ANDA.
After supplemental fact discovery with Hospira was
complete, Astellas filed supplemental infringement conten-
tions articulating a new theory unrelated to the production
of the intermediate (the API) (the compounding infringe-
ment theory) and claiming, as summarized by the district
court, that “[Hospira] infringe[s] the patents-in-suit be-
cause the [API] used in [Hospira’s] proposed products con-
verts to [Form A] during the manufacturing process of
[Hospira’s] finished products.” J.A. 227–28 (emphasis
omitted). Astellas also submitted expert evidence to sup-
port this theory. Hospira filed a motion to strike the sup-
plemental infringement contentions and supplemental
expert reports related to the new theory. The magistrate
judge granted the motion to strike, finding that the com-
pounding infringement theory was untimely and that the
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ASTELLAS US LLC v. HOSPIRA, INC. 6
Pennypack factors3 did not save the untimely disclosures.
J.A. 228–29. Astellas filed objections to the magistrate
judge’s order, which the district court overruled.
Trial went forward on Astellas’s original intermediate
infringement theory, and the court found that Hospira did
not infringe the asserted patent claims. Astellas appealed
only the district court’s grant of the motion to strike its new
infringement theory.4
We have jurisdiction under 28 U.S.C. § 1295(a)(1).
DISCUSSION
We review evidentiary rulings not unique to patent law
for abuse of discretion under the law of the regional circuit,
here the Third Circuit. See Del. Valley Floral Grp., Inc. v.
Shaw Rose Nets, LLC, 597 F.3d 1374, 1379 (Fed. Cir. 2010);
Centocor Ortho Biotech, Inc. v. Abbott Lab’ys., 636 F.3d
1341, 1347 (Fed. Cir. 2011); ZF Meritor, LLC v. Eaton
Corp., 696 F.3d 254, 268 (3d Cir. 2012).
I. Untimeliness
Astellas first argues that its new compounding in-
fringement theory was not untimely. As noted, Astellas’s
original infringement theory argued that crude, Form F,
and/or Form G regadenoson transformed into Form A re-
gadenoson during Curia’s API manufacturing process due
to incidental exposure to water. After Curia modified its
API manufacturing process to decrease the potential for
water exposure, Astellas’s original infringement theory
3 As discussed below, the Pennypack factors are fac-
tors that the Third Circuit has directed district courts to
weigh “[i]n considering whether to exclude evidence relat-
ing to an untimely . . . disclosure.” J.A. 229 n.1.
4 Astellas filed a Rule 8 motion for injunction pend-
ing appeal, which we denied on December 6, 2022.
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ASTELLAS US LLC v. HOSPIRA, INC. 7
became harder to prove. This led Astellas to introduce a
new infringement theory that the API converted to Form A
regadenoson during Hospira’s own compounding process.
During the original period of discovery, Astellas’s ex-
pert testified that he had no opinion as to whether infringe-
ment occurred during the compounding process. See J.A.
1107 (“Q: . . . You’re not offering an opinion that when Hos-
pira does its own manufacturing and takes the API and
converts it to a liquid, that that is causing Form A conver-
sion. Correct? A: Yeah, I think what you mean is, when
they dissolve the regadenoson in water and—and the other
excipients that are present, that doesn’t cause Form A to
form. Is that what you’re asking? Q: Yes. You’re not offer-
ing that opinion. Correct? A: I am not.”).
Astellas did not reveal its new theory until October
2021, close to a year after the original fact discovery period
closed (October 2020), months after the original expert dis-
covery period closed (April 2021), and shortly after supple-
mental fact discovery closed. Because this theory was
based on documents produced to Astellas in August 2020,
Astellas could have raised this theory during the original
period of discovery (which ended in October 2020 for fact
discovery and April 2021 for expert discovery), after it
knew Hospira was going to amend its ANDA (April 2021),
or immediately after Astellas received Hospira’s ANDA
amendments (August 2021). It chose not to.
Rather, Astellas chose to wait to raise its compounding
infringement theory during the supplemental discovery pe-
riod, more than a month after the entry of the supple-
mental discovery order. There was no reason, other than
Astellas’s own litigation choices, that the compounding in-
fringement theory could not have been asserted earlier.
This is not a case where Astellas relied on new information
disclosed in the ANDA amendment to craft a new theory of
infringement. Instead, Astellas simply decided that the
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ASTELLAS US LLC v. HOSPIRA, INC. 8
ANDA amendment would make it harder to prove its orig-
inal infringement theory and decided to try a new theory
related to a process not changed by the amendment.
Nonetheless, Astellas argues that the supplemental
discovery and revised scheduling order permitted Astellas
to develop a new theory of infringement and thus that it
submitted its excluded infringement contentions and ex-
pert opinions by the court-ordered deadline for supple-
mental infringement contentions.
On its face, the Hospira supplemental discovery order
at issue does not state the scope of permitted discovery. See
J.A. 1220–23. However, viewing the order in context
makes it clear that the scope of discovery, and thus the
scope of the supplemental infringement contentions and
expert reports, was limited to the ANDA amendments.
The Hospira supplemental discovery order at issue fol-
lowed an earlier supplemental discovery order as to Apo-
tex, another defendant accused of infringing the Form A
patents. Apotex filed its ANDA amendment, produced to
Astellas on April 6, 2021, to incorporate an amendment to
the DMF of its API supplier. The district court scheduled
a status conference for April 7, 2021, after Apotex produced
its ANDA.
At that conference, Hospira explained that, like Apo-
tex, it also planned to amend its ANDA to incorporate Cu-
ria’s forthcoming DMF amendment with more stringent
requirements.5 Astellas responded that it required an “op-
portunity to take discovery about them [the ANDA amend-
ments]” of both Apotex and Hospira. J.A. 1045.
5 Other defendants also said they planned to simi-
larly amend their ANDAs. For simplicity, we focus only on
Hospira and Apotex.
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ASTELLAS US LLC v. HOSPIRA, INC. 9
After the status conference, Astellas and Apotex filed a
joint status letter where Astellas asked for one supple-
mental discovery schedule for all defendants who had
amended or would be amending their ANDAs (including
Hospira). The district court instead asked Astellas and
Apotex to propose a schedule for supplemental fact discov-
ery regarding Apotex only. Pursuant to that request, As-
tellas and Apotex submitted a joint letter outlining
competing discovery and case schedule proposals but
agreeing as to the scope of discovery. Astellas proposed
that discovery requests should be limited to “issues raised
by the [ANDA] amendments.” See Joint Letter in Accord-
ance with D.I. 709 at 1, Astellas US LLC v. Apotex Inc., No.
18-1675 (D. Del. Apr. 28, 2021), ECF No. 722. Apotex noted
that “[Astellas] proposed that the ‘scope of the supple-
mental discovery’ would be the ‘DMF and ANDA amend-
ments’” and that Apotex had agreed to this proposal. See
id. at 2. The district court adopted Astellas’s proposed re-
vised scheduling order in relevant part, including the pro-
posed deadlines for supplemental infringement
contentions and expert discovery. Although the order itself
did not explicitly incorporate the parties’ agreement as to
the scope of discovery, it noted that supplemental discovery
“should not be expansive.” Oral Order, Astellas US LLC v.
Apotex Inc., No. 18-1675 (D. Del. Apr. 30, 2021), ECF No.
717.
Thereafter, Hospira filed its own ANDA amendment,
and Astellas and Hospira (together with Apotex) agreed to
the second scheduling order, the order at issue here. It pro-
vided deadlines for supplemental fact discovery requests
regarding Hospira. It also provided the same deadlines re-
garding both Apotex and Hospira for the close of expert dis-
covery and Astellas’s final supplemental infringement
contentions. Again, the second revised scheduling order
did not explicitly state the scope of discovery. However, the
parties had agreed that the Apotex discovery was limited
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ASTELLAS US LLC v. HOSPIRA, INC. 10
to Apotex’s ANDA amendments, and there is nothing to
suggest broader discovery as to Hospira. Quite the con-
trary, the same triggering event, the filing of a new ANDA,
led to supplemental discovery against Hospira, and the sec-
ond scheduling order covered both Hospira and Apotex as
to supplemental infringement contentions and expert re-
ports without distinction between the two. Further, the
district court interpreted the second revised scheduling or-
der when granting Hospira’s motion to strike and noted
that it considered the supplemental discovery period to be
limited to “address[ing] new, relevant facts that are related
to the DMF/ANDA amendment processes.” J.A. 228–29,
232. “[G]reat deference is given to a district court’s inter-
pretation of its own order.” WRS, Inc. v. Plaza Entertain-
ment, Inc., 402 F.3d 424, 428 (3d Cir. 2005).
We conclude that the district court did not abuse its
discretion in determining that Astellas’s supplemental in-
fringement contentions and expert evidence were un-
timely. Contrary to Astellas’s argument, nothing in our
decision in Ferring B.V. v. Watson Lab’ys, Inc.-Fla., 764
F.3d 1382 (Fed. Cir. 2014) suggests otherwise. There, we
held that “[a]llowing an [ANDA] amendment is within the
discretion of the district court, guided by principles of fair-
ness and prejudice to the patent-holder.” Ferring B.V., 764
F.3d at 1391. This hardly suggests that supplemental dis-
covery unrelated to the ANDA amendment is required.6
6 Astellas argues that refusing to allow Astellas to
amend its contentions creates undesirable litigation incen-
tives. In fact, the litigation process is not adversely af-
fected by having parties list multiple theories of
infringement in their original contentions with the goal of
whittling them down by the time of trial. Because it is not
undesirable to have parties list all possible infringement
contentions at the case’s outset, it is not unfair to expect
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ASTELLAS US LLC v. HOSPIRA, INC. 11
II. Exclusion of Compounding Infringement
Theory and Evidence
Astellas contends that its new evidence and infringe-
ment theory, even if untimely, should not have been ex-
cluded. In considering whether the district court abused
its discretion in excluding evidence, the Third Circuit con-
siders the five Pennypack factors:
(1) “the prejudice or surprise in fact of the party
against whom the excluded witnesses would have
testified” or the excluded evidence would have been
offered; (2) “the ability of that party to cure the
prejudice”; (3) the extent to which allowing such
witnesses or evidence would “disrupt the orderly
and efficient trial of the case or of other cases in the
court”; (4) any “bad faith or willfulness in failing to
comply with the court’s order”; and (5) the im-
portance of the excluded evidence.
ZF Meritor, 696 F.3d at 298 (quoting Meyers v. Pennypack
Woods Home Ownership Assn., 559 F.2d 894, 904–05 (3d
Cir. 1977)). While there has been no finding here of bad
faith or willfulness (factor (4)), factors (1), (2), (3), and (5)
in this case support the district court’s decision.
First, as to factors (1) and (2), as described above, Hos-
pira was clearly surprised by the new infringement theory
that all possible infringement contentions be presented at
that time. Importantly, this case was not one where the
information necessary to craft an infringement contention
was uncovered by the ANDA amendment. The necessary
information was revealed during the original period of dis-
covery. Moreover, Astellas was permitted to—and did—
update its original infringement theory with supplemental
evidence related to testing on samples taken from Curia’s
optimized API manufacturing process. See J.A. 199.
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ASTELLAS US LLC v. HOSPIRA, INC. 12
that was unrelated to the ANDA amendment and had no
reason to suspect that Astellas would seek to assert the
new compounding infringement theory. During the origi-
nal discovery period, Astellas’s expert explicitly stated that
he was not offering an opinion as to whether the compound-
ing process causes infringement.7 Hospira did not receive
notice of the new theory until about four months before
trial.
The district court correctly concluded that Hospira
would likely be prejudiced by the introduction of the com-
pounding infringement theory at this late stage. Hospira
argued there was not enough time remaining before expert
reports were due and trial was to take place to conduct the
tests necessary to show that no conversion occurred during
the compounding process. It is not clear exactly how long
it would take to run the necessary tests, but Astellas
acknowledged that it could take “weeks.” Reply Br. 24–25
(quoting Hospira’s expert at J.A. 2181). Astellas’s expert
himself admitted that it would take “a lot more time” to run
the best test to determine if there was Form A conversion
during the compounding process. J.A. 1606–08. The dis-
trict court concluded there was not sufficient time for Hos-
pira to even “investigate[] whether to perform additional
(and lengthy) testing procedures in order to assess the ac-
curacy of [Astellas’s] new theory.” J.A. 230.
7 See J.A. 1107 (“Q: . . . You’re not offering an opinion
that when Hospira does its own manufacturing and takes
the API and converts it to a liquid, that that is causing
Form A conversion. Correct? A: Yeah, I think what you
mean is, when they dissolve the regadenoson in water
and—and the other excipients that are present, that
doesn’t cause Form A to form. Is that what you’re asking?
Q: Yes. You’re not offering that opinion. Correct? A: I am
not.”).
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ASTELLAS US LLC v. HOSPIRA, INC. 13
To be sure, the trial date could have been moved yet
again, but the trial date had already been postponed for
over six months to enable the supplemental discovery and
further delay would have prejudiced some other defendants
in the case by effectively extending the presumed generic
launch date. Once a patent owner brings a § 271(e)(2)(A)
infringement action, the FDA generally suspends approval
of the ANDA for a maximum of 30 months. If district court
litigation extends beyond that 30-month window, the FDA
can approve the ANDA, but the generic manufacturer is
often reluctant to bring the generic to market before there
is a district court decision. The 30-month stay for Apotex
and another defendant expired in February 2021, but they,
along with other defendants, agreed not to launch their ge-
neric products until Astellas’s last compound patent ex-
pired on April 10, 2022. See J.A. 1044. So, while Hospira
itself might not have been prejudiced by moving the trial
date, such a move would have been impractical and preju-
dicial to other defendants in the case who sought resolution
by April 2022.8 Understandably, Astellas does not seri-
ously argue that moving the trial date provided a viable
solution.
As to factor (3), the district court concluded that there
was “not time to: (1) incorporate a new and significant in-
fringement theory into the case; (2) allow Defendants to
take relevant discovery; and (3) still keep the trial date.”
J.A. 230. Astellas presents no persuasive evidence to the
contrary and did not demonstrate that the district court’s
determination in this respect was erroneous.
As to factor (5), Astellas argues that under the Third
Circuit’s decision in In re Paoli R.R. Yard PCB Litig., 35
8 While Apotex and other defendants settled before
trial, it was unknown that the settlements would occur at
the time the motion to strike was decided.
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ASTELLAS US LLC v. HOSPIRA, INC. 14
F.3d 717 (3d Cir. 1994), evidence cannot normally be ex-
cluded absent a showing of willfulness or bad faith if the
evidence is critical. However, Astellas has not shown that
the excluded evidence here is critical or of sufficient im-
portance to outweigh the other factors.9 The excluded evi-
dence was merely an alternative theory of infringement,
not the sole theory of infringement. This is in contrast to
the Third Circuit case of ZF Meritor on which Astellas pri-
marily relies.
In ZF Meritor, an antitrust case, the district court
found that ZF Meritor’s damages expert’s (DeRamus’s)
analysis was unreliable insofar as he relied on Strategic
Business Plan (SBP) market share and profit margin in-
puts in making his damages calculations because DeRa-
mus “did not know either the qualifications of the
individuals who prepared the SBP estimates or the as-
sumptions upon which the estimates were based.” 696 F.3d
at 290–91. The district court excluded DeRamus’s testi-
mony. Id. at 295. ZF Meritor asked the district court to
allow DeRamus to revise his damages estimate by replac-
ing SBP inputs with other inputs already included in the
expert report. Id. Although the defendant would “have to
9 Astellas was provided with samples from Curia
produced under the more stringent requirements in July
2021. Astellas ran tests on these samples in which it at-
tempted to simulate the compounding process and show
that Form A conversion occurred during the compounding
process. This is the evidence that was excluded. Astellas
now appears to complain that its evidence concerning
whether the more stringently produced samples converted
to Form A during intermediate manufacturing was ex-
cluded. There is simply no basis in evidence for this asser-
tion. The evidence that was stricken was evidence
regarding the compounding process, not Curia’s intermedi-
ate production.
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ASTELLAS US LLC v. HOSPIRA, INC. 15
respond to new calculations, it [would] not have to analyze
any new data, or challenge any new methodologies.” Id. at
298.
The district court denied ZF Meritor’s request, leaving
it without any damages estimate, and the district court
awarded it $0 in damages because ZF Meritor lacked a
damages theory. Id. at 295–97. The Third Circuit held
that it was an abuse of discretion to not allow ZF Meritor
to amend its damages projection. Id. at 298.
Unlike ZF Meritor, Astellas here was asking to add an
entirely new theory, relying on new test data concerning
the conversion of the API to Form A regadenoson during
conditions it claimed mimicked the compounding process.
Here, also unlike ZF Meritor, excluding the compounding
infringement theory did not leave Astellas without the abil-
ity to pursue infringement. Astellas was still able to pur-
sue its original infringement theory updated with
supplemental evidence: that conversion occurs during API
manufacturing.
Also, when applying the Pennypack factors, the Third
Circuit and this court have found that, when the value of
the excluded evidence is in question, the excluded evidence
does not rise to the level of importance required to reverse
the district court’s exclusion. See Insite Vision Inc. v.
Sandoz, Inc., 783 F.3d 853, 865 (Fed. Cir. 2015) (“[T]he dis-
trict court was correct to at least question the relevance
and probative value of the [European Patent Office] file
history under United States law.”); Semper v. Santos, 845
F.2d 1233, 1238 (3d Cir. 1988) (“[I]t is questionable
whether the rebuttal testimony would have materially
helped Semper.”).
In this case, Astellas’s own expert clearly had stated
that he had no opinion on whether Form A conversion oc-
curred during the compounding process. See J.A. 1107. As-
tellas’s expert also clearly admitted that a test other than
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ASTELLAS US LLC v. HOSPIRA, INC. 16
the test relied on by Astellas would have been the best test
for determining if there was infringement under the com-
pounding infringement theory. J.A. 1606. Additionally,
Hospira’s expert testified that the tests Astellas’s expert
used to show that Form A regadenoson forms during Hos-
pira’s compounding process did not accurately reflect Hos-
pira’s compounding process. J.A. 1955, 1958. Hospira’s
expert further testified that Astellas’s expert’s experiment
“provide[d] no credible evidence that Form G converts to
Form A in Hospira’s manufacturing process.” J.A. 1958.
The district court found Hospira’s expert to be credible at
trial (though not addressing this specific evidence), see J.A.
173, and, in at least some respects, more credible than As-
tellas’s expert. J.A. 195–96. There is thus serious doubt
whether the excluded evidence would ultimately have
helped Astellas.
C ONCLUSION
In sum, “the District Court has considerable discretion
in matters regarding expert discovery and case manage-
ment.” ZF Meritor, 696 F.3d at 297. The district court here
did not abuse its discretion in finding Astellas’s compound-
ing infringement theory and related evidence untimely, nor
did the district court abuse its discretion in concluding that
the Third Circuit’s Pennypack factors supported the dis-
trict court’s decision. Because we conclude that there was
no abuse of discretion, we do not reach Astellas’s argu-
ments as to whether any error was prejudicial or harmful.
We therefore affirm the district court.
AFFIRMED
Case: 22-1878 Document: 62 Page: 16 Filed: 12/30/2022

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