FILED

NOT FOR PUBLICATION

MAR 28 2022

UNITED STATES COURT OF APPEALS MOLLY C. DWYER, CLERK

U.S. COURT OF APPEALS

FOR THE NINTH CIRCUIT

In re: INCRETIN-BASED THERAPIES No. 21-55342

PRODUCTS LIABILITY LITIGATION,

______________________________ D.C. No. 3:13-md-02452-AJB-MDD JEAN ADAMS, On Behalf of Herself and All Other Similarly Situated Plaintiffs,

MEMORANDUM*

Plaintiff-Appellant,

v.

NOVO NORDISK A/S,

Defendant-Appellee.

Appeal from the United States District Court for the Southern District of California Anthony J. Battaglia, District Judge, Presiding

Argued and Submitted March 7, 2022 San Francisco, California

Before: S.R. THOMAS and McKEOWN, Circuit Judges, and ORRICK,** District Judge.

* This disposition is not appropriate for publication and is not precedent except as provided by Ninth Circuit Rule 36-3. ** The Honorable William Horsley Orrick, United States District Judge for the Northern District of California, sitting by designation. Jean Adams, on behalf of herself and similarly situated plaintiffs, appeals the

summary judgment granted by the district court in favor of Novo Nordisk A/S

(“Novo”) on plaintiffs’ claim that Novo’s product liraglutide can cause pancreatic

cancer, and that Novo failed to adequately warn of this risk.

Because the parties are familiar with the factual and procedural history of

this case, we need not recount it here. We review orders granting summary

judgment de novo, but we review for abuse of discretion the district court’s

decision to exclude the testimony of an expert witness. Wendell v.

GlaxoSmithKline, 858 F.3d 1227, 1231 (9th Cir. 2017). We affirm.

I

The district court did not abuse its discretion in excluding the testimony of

Dr. Robert Gale after conducting an extensive hearing pursuant to Daubert v.

Merrell Dow Pharms., Inc., 509 U.S. 579 (1993). Considerations relevant to

evaluating the reliability of an expert’s theory include, but are not limited to,

whether the theory can be tested or has been subject to peer review, its known error

rate, and whether it is generally accepted in the scientific community. Id. at

593–94. On appeal, we afford the district court “the same broad latitude when it

decides how to determine reliability as it enjoys in respect to its ultimate reliability

determination.” Kumho Tire Co. v. Carmichael, 526 U.S. 137, 142 (1999).

2 In making its Daubert determination, the district court properly relied on the

uncontested fact that Dr. Gale did not independently review studies that had been

published between 2015 and Dr. Gale’s final 2019 report, all of which found no

causal relationship between liraglutide use and the development of pancreatic

cancer.

The district court did not abuse its discretion in finding that Dr. Gale’s

reliability was further impeded by his failure to explain his “weight-of-the-

evidence” methodology. To demonstrate testability under Daubert, an expert must

provide sufficient explanation for their methodology such that “[s]omeone else

using the same data and methods [would] be able to replicate the result[s].” City of

Pomona v. SQM N. Am. Corp., 750 F.3d 1036, 1047 (9th Cir. 2014) (first alteration

in original) (citation and internal quotation marks omitted). The record supports

the district court’s conclusion that the expert’s reports did not provide a

meaningful methodological explanation. In the absence of such an explanation, the

district court had no means to ensure that Dr. Gale’s “conclusions were not mere

subjective beliefs or unsupported speculation.” Claar v. Burlington N. R.R. Co., 29

F.3d 499, 502 (9th Cir. 1994).

Finally, the district court properly considered the fact that Dr. Gale is

“alone” in the scientific community in concluding that the relevant compounds

3 cause pancreatic cancer, “despite years of research into the pancreatic safety of

incretin mimetics conducted by various medical, scientific, and regulatory

entities.” See Daubert, 509 U.S. at 594.

Our decision in Wendell is not to the contrary. There, we did emphasize that

experts may rely on their own “extensive clinical experience,” in combination with

a review of all relevant existing literature, in carrying out a differential diagnosis

and formulating an opinion on specific causation. See 858 F.3d at 1234–35, 1237.

But the expert reports here did not provide any differential diagnoses or opinions

on specific causation, and nothing in Wendell absolves expert witnesses of the

general and longstanding requirement that they explain their methods with enough

detail that their results can be replicated. See Claar, 29 F.3d at 502.

For these and the other reasons provided by the district court, we conclude

that the district court did not abuse its considerable discretion in excluding Dr.

Gale’s testimony under Daubert.

II

Plaintiffs asserting a failure-to-warn claim in the pharmaceuticals context

must prove general causation—that is, that “the substance at issue had the capacity

to cause the harm alleged.” In re Hanford Nuclear Reservation Litig., 292 F.3d

1124, 1133 (9th Cir. 2002). Proving this element generally requires expert witness

4 testimony. See Lust by and through Lust v. Merrell Dow Pharms., Inc., 89 F.3d

594, 598 (9th Cir. 1996). Dr. Gale’s expert testimony was the only evidence in the

record that directly supported the plaintiffs’ theory of general causation. Thus,

with the exclusion of the expert testimony on causation, the district court properly

entered summary judgment.

Given our resolution of this case, we need not—and do not—opine on any

other theory or argument urged by the parties, or the alternate basis for summary

judgment given by the district court.

AFFIRMED.

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