Plaintiffs attempting to capitalize on Pfizer’s 2004 guilty plea for promoting off-label uses of the epilepsy drug Neurontin have had a tough go of it. Last May, Boston federal district court judge Patti Saris denied a motion for class certification by a putative class of health insurance companies and patients who claimed they would have chosen cheaper and more effective drugs if it weren’t for Pfizer’s fraudulent promotion of Neurontin.

A motion for reconsideration is pending, but in the meantime, three third-party payers — Aetna, Guardian Life Insurance and Kaiser Health Foundation Health Plan — forged ahead with their own cases. Last week Pfizer’s lawyers at Skadden, Arps, Slate, Meagher & Flom succeeded in scuttling two of them. Saris granted summary judgment against Aetna and Guardian Life, ruling that only Kaiser had offered sufficient proof that it paid for Neurontin as a result of Pfizer’s alleged fraud.

Saris found that Kaiser, unlike Aetna and Guardian Life, took a hands-on approach in researching Neurontin’s effectiveness, including direct communications with Pfizer about the drug. “Kaiser has provided evidence allowing a reasonable inference of causation to be drawn in its favor,” the judge wrote.

In a statement, Pfizer said that Saris’ refusal to grant summary judgment against Kaiser “represents a decision only on one motion and is not a decision on the merits of Kaiser’s lawsuit. In fact, when deciding this motion for summary judgment, the court was required to consider the evidence in the light most favorable to the plaintiff. Kaiser must still prove its claims at trial.”

A trial date has been set for Feb. 22. Pfizer is represented by Mark Cheffo of Skadden Arps.

Thomas Sobol of Hagens Berman Sobol Shapiro, who represents Kaiser, Aetna and Guardian, did not return our call.

This article first appeared on The Am Law Litigation Daily blog on