In Re: Mirena IUS Levonorgestrel-Related Products Liability Litigation (No.
19-2155
2d Cir.Dec 8, 2020Background
- Mirena is a levonorgestrel-releasing intrauterine device (IUD) manufactured by Bayer; plaintiffs alleged Mirena caused idiopathic intracranial hypertension (IIH).
- Hundreds of cases were centralized in an MDL in the Southern District of New York; the court prioritized resolving whether plaintiffs could show admissible evidence of general causation.
- The district court held a Daubert hearing on general-causation experts, heard seven plaintiff experts and multiple Bayer experts, and issued a detailed opinion excluding all of plaintiffs' experts under Rule 702/Daubert.
- After excluding plaintiffs' experts, the district court granted Bayer summary judgment, concluding plaintiffs lacked admissible evidence that Mirena is capable of causing IIH (general causation).
- Plaintiffs appealed, arguing the Daubert exclusions were improper, summary judgment was erroneous, and the court unduly limited discovery; the Second Circuit affirmed for substantially the reasons given by the district court.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Admissibility of plaintiffs' experts under Daubert/Rule 702 | Experts used accepted methods and court improperly scrutinized conclusions over methodology | Experts' analyses were methodologically unreliable and unsupported by the literature | Court did not abuse discretion: it rigorously examined methods and properly excluded experts whose methodologies and inferential steps were unreliable |
| Requirement to prove general causation before specific causation | Plaintiffs argued some states permit specific-causation evidence earlier and that discovery limits prevented meeting general-causation threshold | Bayer: plaintiffs must present admissible general-causation evidence to proceed on complex medical causation claims | Court held state law requires some general-causation showing; without admissible experts plaintiffs failed to meet that requirement |
| Sufficiency of remaining evidence after expert exclusion to survive summary judgment | Plaintiffs contended portions of excluded reports or differential-diagnosis evidence could still establish causation | Bayer: without admissible expert opinion, plaintiffs have no competent evidence of general causation | Summary judgment affirmed: no reasonable juror could find general causation on admissible evidence alone |
| Discovery scope and fairness | Plaintiffs said court prevented discovery needed to develop general-causation proof | Bayer maintained discovery afforded was sufficient and the court managed scope reasonably | Court exercised broad discretion over discovery; orders (including extensive document production) were within bounds and did not deprive plaintiffs of substantial rights |
Key Cases Cited
- Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579 (1993) (trial court gatekeeping role for expert testimony reliability)
- Amorgianos v. Nat'l R.R. Passenger Corp., 303 F.3d 256 (2d Cir. 2002) (an expert's analysis must be reliable at each step; abuse-of-discretion review of Daubert rulings)
- Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999) (Daubert gatekeeping applies to all expert testimony, not only scientific)
- Gen. Elec. Co. v. Joiner, 522 U.S. 136 (1997) (district court's exclusion of expert testimony reviewed for abuse of discretion)
- Zuchowicz v. United States, 140 F.3d 381 (2d Cir. 1998) (standard for reviewing admission/exclusion of expert testimony)
- Ruggiero v. Warner-Lambert Co., 424 F.3d 249 (2d Cir. 2005) (role and limits of differential diagnosis in proving general causation)
- In re Mirena IUD Prods. Liability Litig. I, [citation="713 F. App'x 11"] (2d Cir. 2017) (prior MDL decision affirming need for general-causation evidence)
- In re Agent Orange Prod. Liab. Litig., 517 F.3d 76 (2d Cir. 2008) (district court's wide latitude in discovery management)