Earlier this year, we discussed the Eastern District of Pennsylvania’s decision to enter a Lone Pine order – that is, a case management order that requires all plaintiffs to produce evidence establishing specific elements of their claim – in the Zostavax MDL. That post can be viewed here. We lauded that Lone Pine order’s potential to save the parties considerable time and expense while advancing the purposes of the MDL by weeding out meritless cases. That potential recently came to fruition: the court in the Zostavax MDL dismissed 1,189 cases for failure to comply with the Lone Pine order. In re: Zostavax (Zoster Vaccine Live) Prods. Liab. Litig., 2022 WL 17477553 (E.D. Pa. Dec. 6, 2022).

Zostavax is a vaccine intended to prevent shingles, a viral infection caused by the varicella-zoster virus (“VZV”). Zostavax works by introducing a weakened strain of VZV (“v-Oka”), triggering an immune response in the recipient and priming the immune system against infections from non-vaccine sources (i.e., “wild-type” strains). Over half of the plaintiffs in the MDL – referred to as the “Group A cases” – claimed that the vaccine caused them to develop shingles. But that claim ran into a serious causation issue when the initial bellwether cases were worked up: VZV is responsible for both shingles and chickenpox. VZV remains in the body for life, so an individual who had chickenpox as a child faces an ongoing risk of the virus reactivating and causing shingles in adulthood. As the MDL court noted, plaintiffs who alleged that the vaccine caused their cases of shingles had to “rule out the obvious alternative cause that the wild-type virus reactivated.” Yet, despite the existence of a simple laboratory test that can distinguish between infection by the vaccine strain (v-Oka) and infection by a wild-type strain, none of the bellwether plaintiffs produced results from such a test – or any other evidence ruling out a wild-type infection.  Noting that such evidence was critical to causation in each plaintiff’s case, the court issued a Lone Pine order requiring the plaintiffs in the Group A cases to provide that evidence within 90 days.

It turns out that most plaintiffs in Group A were unable to meet the court’s call. They argued that they could prove specific causation without lab testing, and that unidentified experts supported their assertion that, except in rare circumstances, every case of shingles after vaccination with Zostavax is “more likely than not caused by” the vaccine. The court deemed those bald claims insufficient because the plaintiffs had not identified the experts in question, cited to any reports, or even explained away contradictory prior testimony by the bellwether plaintiffs’ causation expert. Thus, the court dismissed 1,189 Group A cases. The court explained that there was “nothing before the court to indicate the Group A plaintiffs can ever succeed on the merits” and that the defendant would be severely prejudiced if the court permitted these meritless cases to remain on the MDL docket.

The dismissal of these cases for failure to comply with the Lone Pine order illustrates the potential power of this case management tool. As the court in the Zostavax MDL adeptly noted, defendants suffer severe prejudice when meritless cases lurk in large MDL inventories, enabling them to be swept up in settlement and/or proceed to expensive – but ultimately futile – case-specific discovery. As multidistrict litigation continues to dominate federal dockets, the Lone Pine order should be a top-of-mind tool for flushing away meritless cases.