Products Liability Law Daily Exclusion of experts dooms products liability claims against makers of Mirena IUD
Wednesday, December 9, 2020

Exclusion of experts dooms products liability claims against makers of Mirena IUD

By Pamela C. Maloney, J.D.

The Second Circuit affirmed a lower court’s finding that all seven experts testifying on behalf of women who developed complications as a result of using Bayer’s Mirena device should be excluded.

In a multi-district litigation relating to Bayer’s Mirena intrauterine device, a New York federal district court’s exclusion of all seven of the plaintiffs’ general causation experts after finding that their testimony fell short of the Daubert reliability standards was affirmed by the U.S. Court of Appeals for the Second Circuit. The Second Circuit also affirmed the lower court’s ruling that as a matter of law, the plaintiffs could not establish general causation without expert testimony (In re: Mirena IUS Levonorgestrel-Related Products Liability Litigation (No. II), December 8, 2020, per curiam).

Alleging that they developed idiopathic intracranial hypertension (IIH) as a result of using the Mirena Intrauterine System—a plastic T-shaped intrauterine device (IUD) that releases a synthetic steroid hormone called levonorgestrel (LNG) into the uterus to prevent pregnancy—women from across the United States filed a class action lawsuit against Bayer Pharma Ag, Bayer Oy, and Bayer Healthcare Pharmaceuticals Inc., the manufacturers of Mirena. The class action lawsuit, which was consolidated by the Judicial Panel on Multidistrict Litigation in the Southern District of New York for pretrial proceedings, set forth claims for negligence, manufacturing defect, design defect, failure to warn, breach of implied and express warranties, negligent misrepresentation, fraudulent misrepresentation, fraud, and state consumer fraud violations. Upon the conclusion of a Daubert-hearing, the district court granted Bayer’s motion to exclude all seven of the plaintiffs’ general causation experts, holding that their testimony fell short of the reliability standards set forth in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993). Explaining that without expert witnesses, the plaintiffs had insufficient evidence to establish general causation, the district court granted Bayer’s motion for summary judgment and closed all of the cases in the MDL. The plaintiffs appealed, arguing that the district court abused its discretion by (1) focusing on the plaintiffs' experts' conclusions rather than their methodologies, (2) requiring the experts to back their opinions with published studies that definitively supported their conclusions, and (3) taking a "hard look" at the experts' methodology. The plaintiffs also challenged the grant of summary judgment, arguing that there was sufficient specific causation evidence to send the case to the jury.

Reliability of methodology. In response to the arguments that the district court’s analysis of each expert was too "rigorous," and that the district court impermissibly had focused on their experts’ conclusions instead of their methodologies, the Second Circuit opined that in order to determine whether an expert’s methodology was reliable at every step in the process, district courts should undertake a rigorous examination of the facts on which the expert relied, the method by which the expert drew an opinion from those facts, and how the expert applied the facts and methods to the case at hand. The Second Circuit also found that although the plaintiffs could-and did-challenge the correctness of the lower court’s reliability analysis, they had no basis to argue that the court’s opinion did not engage in a detailed analysis as to whether the experts had applied their methodologies reliably.

Finally, the district court’s finding that the experts were required to support their opinions with published studies that definitively supported those conclusions was not error. Generally, the lack of textual support went to the weight, rather than the admissibility of the expert’s testimony, but when an expert did not utilize reliable scientific methods to reach a conclusion, the court was well within its discretion to consider whether the expert’s conclusions were generally accepted by the scientific community.

Causation evidence. The plaintiffs also challenged the district court’s ruling that without expert testimony, they could not prove general causation, arguing that evidence provided on specific causation was sufficient and that the district court erred in precluding differential-diagnosis evidence that would have established that Mirena most likely caused their IIH. However, the plaintiffs failed to point to any state that did not have a general causation requirement for the types of claims presented. In addition, the plaintiffs failed to explain what portions of their expert reports should have been carved out as admissible on the issue of specific causation. Based on the district court’s in-depth analysis of each of the plaintiffs’ proffered experts, their assertion that some of the evidence in those reports could have created a material issue of fact as to specific causation was mere speculation.

The district court’s exclusion of the differential-diagnosis evidence was upheld on the ground that the plaintiffs had failed to explain the rigor of the differential diagnosis performed, the expert's training and experience in performing differential diagnoses, and the type of illness or injury at issue, all of which were necessary to support the admissibility of this evidence to establish general causation. In addition, the question of whether Mirena actually caused plaintiffs’ IIH was an issue of specific causation, not general causation, without which the plaintiffs could not proceed on their underlying claims.

Finally, the appellate court rejected the plaintiffs’ challenge to the manner in which the district court had conducted discovery with regard to general causation evidence, noting that the lower court had ordered Bayer to produce millions of documents from more than 50 custodians, 41 of whom had been identified in previous Mirena IUD MDL, and had allowed the plaintiffs to obtain documents from 11 new custodians. The district court considered the relevance and proportionality of all discovery requests and had responded with thorough, well-reasoned discovery orders throughout the litigation.

The case is No. 19-2155.

Attorneys: Martin Daniel Crump (Davis & Crump, P.C.), Lawrence L. Jones, II (Jones Ward PLC), and Maxwell Kennerly (Kennerly Loutey LLC) for Abra Coning. Lisa Schiavo Blatt (Williams & Connolly LLP) and Shayna Cook (Brennan & Baum LLP) for Bayer Pharma AG, Bayer Oy and Bayer Healthcare Pharmaceuticals Inc.

Companies: Bayer Pharma AG; Bayer Oy; Bayer Healthcare Pharmaceuticals Inc.

MainStory: TopStory ExpertEvidenceNews CausationNews ClassActLitigationNews MedicalDevicesNews ConnecticutNews NewYorkNews VermontNews

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