Unlike past pharmaceutical litigation, lawsuits over allegations that women’s use of Zoloft during their pregnancies caused birth defects in their children are coalescing in federal court instead of state courts across the country, a defense attorney for drugmaker Pfizer said during a multidistrict litigation court hearing Monday.

Defense counsel Mark S. Cheffo of Skadden, Arps, Slate, Meagher & Flom in New York told the panel that the number of state court cases is shrinking.

One potential sign that the nascent litigation is centralizing in federal court in Philadelphia is that plaintiffs counsel gave notice last week of a motion to withdraw 36 cases that they had sought to remand to the Philadelphia Court of Common Pleas.

Richard A. Freese, a Birmingham, Ala., attorney with Freese & Goss, said that since his co-counsel and he argued their motions to remand "we’ve stayed in close contact with lawyers for Pfizer and the PSC [plaintiffs steering committee]. For a number of reasons, not the least of which was it became obvious to us we were recreating a wheel that didn’t need to be created … it just seemed to us we’d be better off leaving our cases here that were removed here."

Freese and other plaintiffs attorneys had fought Pfizer’s decision to remove their cases from the Philadelphia Court of Common Pleas. While Pfizer contended that Wolters Kluwer Health, a Pennsylvania corporation the plaintiffs allege was negligent in the publication of the risks and benefits of using Zoloft during pregnancy in its patient education monographs, was fraudulently joined, the plaintiffs originally requested that Zoloft be designated as a mass tort program in the Philadelphia Court of Common Pleas’ Complex Litigation Center. Patient education monographs accompany drugs when the drugs are dispensed to patients.

Cheffo said that he hoped the decision to dismiss state court cases by Freese and Rosemary Pinto of Feldman & Pinto in Philadelphia, and David P. Matthews of Matthews & Associates in Houston, was because of confidence in the MDL and the PSC.

"We will note that the reason for the motions to remand in each of the local cases was the addition of Wolters Kluwer as one of the defendants," said U.S. District Judge Cynthia M. Rufe of the Eastern District of Pennsylvania, but that issue does not show up in other cases from across the country.

If Wolters Kluwer remains a defendant in other Philadelphia state-court cases, "that just says we’ll be doing the same discovery," Rufe said.

Freese said that the cases in which Wolters Kluwer is named a defendant could also have been filed in federal court, and "our intention is to continue to prosecute cases against Wolters Kluwer."

While Freese and his co-counsel’s motion addressed most of the cases in which plaintiffs lawyers sought to get an order from Rufe remanding the cases to the Philadelphia Court of Common Pleas, Rufe said that some of them are still outstanding.

Another factor that could be driving cases into the federal MDL is Pfizer’s stance that, before it will enter tolling agreements, those cases must be refiled in federal court. Pfizer, when entering tolling agreements, sets as a "condition precedent" that cases that are dismissed under those agreements must be refiled in federal court, Cheffo said.

A co-lead counsel of the plaintiffs steering committee’s executive committee, Mark P. Robinson Jr. of Robinson Calcagnie Robinson Shapiro Davis in Newport Beach, Calif., said that while he has a handful of cases in California state court, he is "committed to the MDL. We will be talking to our state court friends and trying to get them to come to the MDL but I also believe that we really need to be productive on discovery."

Robinson emphasized more than once "we’ve got to get discovery against Pfizer," and the production of documents would lead to many more cases being filed.

"A lot depends upon whether or not we’re going to get these documents," Robinson said. "Getting the documents is where the rubber hits the road. That’s my number one thing for the next six months."

Rufe said she was not trying to solicit cases to the MDL but she wants to set an example of how to run the litigation, including coordinating with state litigation.

The MDL also should not be viewed as a competitor to state courts, Rufe said. While there was some flavor of a competition between the MDL and Philadelphia Court of Common Pleas in the diabetes drug Avandia litigation, "we were always racing to the same goal," the judge said.

Cheffo said that producing documents is important on both sides and is a "bilateral joint exercise. We’ll continue to meet our obligations."

Rufe also said that a dual approach to the litigation is essential in the Zoloft MDL in terms of developing the science evidence, which is important to Pfizer, and discovery of potential liability evidence, which is important to the plaintiffs.

The discovery plan sets out relatively early trial dates while also setting out early hearings over the science behind the plaintiffs’ allegations.

"It’s a rocket docket schedule," said the other co-lead counsel of the plaintiffs steering committee’s executive committee, Dianne Nast, of Nast Law in Philadelphia.

Zoloft, a selective serotonin reuptake inhibitor, has been on the market for 20 years and is used for treating depressive, obsessive-compulsive, panic, post-traumatic stress, premenstrual dysphoric and social anxiety disorders, according to court papers.

Amaris Elliott-Engel can be contacted at 215-557-2354 or aelliott-engel@alm.com. Follow her on Twitter @AmarisTLI.