Over 50 Zoloft lawsuits should be dismissed because those plaintiffs have failed to comply with their discovery obligations, defendants Pfizer Inc. and Greenstone LLC argued.

The pharmaceutical defendants said that 66 plaintiffs did not submit initial fact sheets by the deadlines set by the court, and that some of those plaintiffs, as well as 17 other plaintiffs, did not authorize the collection of records within the applicable deadlines.

Fifty-five of those plaintiffs, who allege that the use of the antidepressant caused birth defects, have not responded and should have their claims dismissed with prejudice, the defendants argued in court papers.

Failing to provide the fact sheets and the authorization to access records prejudiced the defendants, they said, because they argue that information is vital to their ability to mount a defense and to identify what they should be focusing on in discovery.

In another motion, Pfizer is objecting to notices by the plaintiffs seeking to depose Dr. Patrizia Cavazzoni, Pfizer’s senior vice president of safety, established pharma & generic regulatory, and Dr. Joseph Feczko, Pfizer’s chief medical officer and president of worldwide development until his retirement from Pfizer in 2009.

Depositions for high-level executives “present the potential for abuse and harassment, especially where the corporation produces consumer goods and consequently may be subject to a high volume of lawsuits,” Pfizer said.

Both oversaw many departments working on hundreds of medicines, Pfizer said. Moreover, Feczko cannot be compelled to sit for a deposition based solely on notice because he has not been personally served a subpoena, the drugmaker said.

The plaintiffs steering committee “must present credible evidence that Drs. Cavazzoni and Feczko had unique, personal knowledge relevant to the claims and that such information cannot be obtained through less burdensome means than the depositions of senior executives,” the drugmaker said.

The MDL judge, U.S. District Judge Cynthia M. Rufe of the Eastern District of Pennsylvania, also granted a motion to move the first bellwether trial back from November to January.

Amaris Elliott-Engel contributes to law.com.