(CN) - A federal judge allowed Pfizer to call an expert witness to testify that the epilepsy drug Neurontin aka gabapentin is safe, in a consolidated case that claims the drug is linked to suicidal behavior.
The plaintiffs claim that Pfizer paid Dr. Robert Gibbons "several hundred thousand dollars" for a litigation report, which he excerpted without proper disclosure in articles submitted to peer-reviewed journals.
Plaintiffs sought several times to exclude Gibbons' testimony, since he signed an expert declaration in April 2008.
Since that time, the plaintiffs have accused Gibbons of making false testimony in depositions, withholding approximately 1,000 documents during discovery and failing to inform peer-reviewed journals that his primary source of funding was Pfizer, not the National Institute of Health.
In a partially redacted 8-page memorandum from April 2010, Pfizer's lawyer Ana Francisco chided plaintiffs' attorney Jack W. London for publicly "cast[ing] aspersions" on Gibbons by referring to Pfizer's payment to him, in the "Comments" section of an online article in the Los Angeles Times.
Francisco wrote that Gibbons complied with discovery demands, disclosed the funding he received from Pfizer and has been subject to "unfounded attacks."
U.S. Magistrate Judge Leo Sorokin tersely denied two of the plaintiffs' motions to exclude reports or testimony from Gibbons, with a 2-page order of July 1, 2009, stating: "Plaintiff has not established a basis to warrant striking either Gibbons report as a sanction."
Plaintiffs challenged the magistrate's decision days later, in a 12-page motion arguing that the order "did not set out a standard by which [Sorokin] assessed the evidence supporting plaintiffs' motion, nor is it possible to determine how he applied any standard that was employed."
But U.S. District Judge Patti Saris allowed Gibbons to testify, upholding Sorokin's order in a 27-page memorandum of March 18 this year, which did not address the funding of Gibbons' research, or the allegations of false testimony.
As described in the March 18 order, the products liability lawsuit stems largely from a U.S. Food and Drug Administration alert pointing to a statistical linkage between gabapentin and suicidal behavior.
In early 2005, the FDA initiated an inquiry on whether use of anti-epileptic drugs led to an elevated risk of suicidal behavior. Three years later the FDA issued an Alert, stating that people using the drug had approximately twice the risk as those in placebo control groups.
Pfizer, which acquired co-defendant Warner-Lambert in 2000, sought to call Gibbons as an expert to rebut the FDA's findings. He is director of the Center for Health Statistics and a professor at the University of Illinois at Chicago.
Gibbons published studies on gabapentin in two peer-reviewed journals in 2010. The articles reported that the FDA analysis drew primarily from data on "suicidal thoughts or behavior," rather than suicide attempts.
In one paper, Gibbons wrote that bipolar patients who received anti-epileptic drugs attempted suicide less frequently than those who were untreated.
Another Gibbons report "found that there was no significant difference in suicide attempt rates before versus after patients received gabapentin prescriptions."
Judge Saris wrote that the plaintiffs' expert witness, Dr. Sander Greenland, had "equally impressive" credentials, as a professor at UCLA and a member of the FDA's Drug Safety and Risk Advisory Committee.
Greenland disputed Gibbons' interpretation of the data, saying it improperly drew a conclusion from a correlation in data. He cited the scientific principle that "an association is not equivalent to causation."
Without commenting on the force of either side's arguments, Judge Saris allowed both experts, saying her "gatekeeping" role should be limited to the experts' qualifications and methodology.
"Dr. Greenland's criticism may affect the weight to be given to the opinion, but do not preclude admissibility," Judge Saris wrote.
A jury in the same court already has fined Pfizer $141 million for illegally pushing Neurontin for unapproved uses, such as treating bipolar disorder and migraines, in a separate but related case that ended March 2010.
The jury's $47 million penalty was automatically tripled under the federal anti-racketeering law.
Doctors are permitted to prescribe drugs for off-label uses, but drug companies cannot push them for that.