In re Chantix (Varenicline) Products Liability Litigation
889 F. Supp. 2d 1272
N.D. Ala.2012Background
- MDL action regarding Chantix and neuropsychiatric injuries; FDA warnings expanded 2007–2009; Daubert motions challenge six plaintiffs’ experts on general causation; court conducted a July 24, 2012 hearing and prepared a ruling; focus is whether Chantix can cause the alleged injuries and the admissibility of experts’ methodologies; labeling warnings addressed in prior ruling; court adopts flexible Daubert analysis and gatekeeper role; evidence reviewed includes FDA reports, EMA actions, and post-marketing data; court denies most exclusion but bars certain testimony about what defendant knew or misled the FDA.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Daubert reliability of experts’ methodologies | Olmstead, Furberg, Kramer rely on data analyses and weight of evidence | Methods unreliable; improper use of uncontrolled data; seeks exclusion | Denial of exclusion; methods considered reliable enough for trial |
| Whether experts may testify about defendant’s knowledge and misrepresentation | Experts may discuss what Pfizer knew | Such testimony is speculative and improper | Denied to extent of testimony about what defendant knew or misled the FDA; allowed as to other non-knowledge aspects |
| Bechara and dopamine depletion theory admissibility | Dopamine depletion is plausible mechanism linking Chantix to neuropsychiatric effects | Extrapolation from animal studies; lack of direct human data; may be speculative | Bechara may testify; cross-examination to address limitations; theory admitted as tentative mechanism |
| Dose-response relevance to general causation | Evidence supports dose-response relationships or dechallenge/rechallenge data | McClain/Accutane caution against relying on dose-response without direct human data | Dose-response evidence admissible; not fatal to reliability; issues for cross-examination and weight |
| Labeling adequacy testimony | Experts may opine on whether label should have disclosed risks | Label adequacy not within experts’ scope; FDA-related opinions excluded | Kramer’s labeling opinions excluded; Glenmullen’s allowed on should-have-known but not what defendant knew |
Key Cases Cited
- In re Neurontin Marketing, Sales Practices, and Products Liability Litigation, 612 F. Supp. 2d 116 (D. Mass. 2009) (general causation and Daubert gatekeeping in pharmaceutical cases; relies on Reference Guide on Medical Testimony)
- Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (Supreme Court 1993) (gatekeeping for admissibility of expert testimony)
- Kumho Tire Co., Ltd. v. Carmichael, 526 U.S. 137 (Supreme Court 1999) (flexible Daubert factors; relevance to expert reliability)
- Matrixx Initiatives, Inc. v. Siracusano, 131 S. Ct. 1309 (Supreme Court 2011) (statistical significance not sole determinant; other evidence admissible)
- Rider v. Sandoz Pharmaceuticals Corp., 295 F.3d 1194 (11th Cir. 2002) (epidemiology not always required for causation; weight of evidence considered)
- In re Prempro Prods. Liab. Litig., 738 F. Supp. 2d 887 (E.D. Ark. 2010) (guidance on when statistical significance should control; weight of evidence)
- Turner v. Iowa Fire Equip. Co., 229 F.3d 1202 (8th Cir. 2000) (reliable differential diagnosis admissible)
- Westberry v. Gislaved Gummi AB, 178 F.3d 257 (8th Cir. 1999) (admissibility of epidemiological testimony with weight to jury)