The number of cases involving the anti-psychotic drug Risperdal almost tripled in the first half of 2017, jumping from approximately 2,000 cases at the beginning of the year to more than 5,500 as of June 2017, comprising the largest mass tort litigation in Philadelphia.

The new filings in the Risperdal litigation were largely triggered when Johnson & Johnson terminated tolling agreements on thousands of cases, which had paused the statute of limitations deadline. A Johnson & Johnson subsidiary, Janssen Pharmaceuticals, Inc., manufactures Risperdal.

The Risperdal litigation mostly involves a condition called gynecomastia, which causes breast tissue enlargement in males. Risperdal was originally approved in 1993 to treat schizophrenia in adults. In 2006, clinical studies linked an increased risk of gynecomastia in male adolescents to Risperdal use. The Risperdal gynecomastia lawsuits allege the manufacturer did not sufficiently warn doctors and patients of the male breast growth problem, and that Johnson & Johnson and Janssen Pharmaceuticals failed to properly share information with the FDA.

In 2016, a Pennsylvania jury awarded $70 million to a teenage male who claimed Risperdal caused him to grow enlarged breasts. The jury found that Johnson & Johnson failed to warn Risperdal could cause gynecomastia, and that the company “intentionally falsified, destroyed, or concealed records” that Risperdal could cause boys to develop breasts.

More Risperdal cases may be filed in the wake of the United States Supreme Court’s recent jurisdictional decision in Bristol-Myers Squibb Co. v. Superior Court of California, San Francisco County. In that case, a group of plaintiffs sued Bristol-Myers Squibb Company (BMS), asserting claims based on injuries allegedly caused by the BMS drug Plavix. Of the more than 600 plaintiffs, 592 are residents of states other than California. BMS is incorporated in Delaware and headquartered in New York. It maintains substantial operations in New York and New Jersey, and engages in business activities and sells Plavix in California. The nonresident plaintiffs did not allege that they obtained Plavix from a California source, that they were injured by Plavix in California, or that they were treated for their injuries in California. The United States Supreme Court found that California courts lack specific jurisdiction to consider the nonresidents’ claims. In order for a state court to exercise specific jurisdiction, the suit must arise out of or relate to the defendant’s contacts with the forum.

Ninety-four percent of the most recent filings in the Risperdal mass tort litigation are from outside of Pennsylvania. Plaintiffs from all over the country have filed suit in Philadelphia, which is a home venue for Janssen Pharmaceuticals.