LAWRENCE F. STENGEL, District Judge.
This case is part of a Multidistrict Litigation (MDL) involving claims of liver damage from the use of Tylenol at or just above the recommended dosage.
The admissibility of expert testimony is governed by Federal Rules of Evidence 702 and 703 as well as by
"[B]ecause expert evidence is often more misleading than other evidence, Rule 403 gives a judge more power over experts than over lay witnesses."
Federal Rule of Evidence 702 has three major requirements: 1) the expert must be qualified; 2) the expert must testify about matters requiring scientific, technical, or specialized knowledge; and 3) the testimony must assist the trier of fact.
An expert's qualifications may include education, provided it is in a field related to the one in which the expert intends to testify.
However, this does not mean that the "best qualified" expert must testify. "[W]itnesses may be competent to testify as experts even though they may not, in the court's eyes, be the `best' qualified."
This Circuit interprets the second factor as one of "reliability," i.e., the testimony is admissible so long as the process or technique the expert used in formulating the opinion is reliable.
"Rule 702 grants the district judge the discretionary authority, reviewable for its abuse, to determine reliability in light of the particular facts and circumstances of the particular case."
The third factor "is typically understood in terms of whether there is a sufficient `fit' between the expert's testimony and the facts that the jury is being asked to consider."
Under Federal Rule of Evidence 703, the data underlying the expert's opinion is the central focus. Rule 703 states:
Dr. Robert Nelson offers opinions on general causation, pharmacovigilance, pharmacoepidemiology, drug safety, and drug regulation.
Dr. Nelson offers an overview of the information that was known about the risks of acetaminophen at the time of the decedent's death, as they relate to hepatotoxicity. He outlines what a reasonable drug company should have done to reduce these risks (i.e., pharmacovigilance), based on his experience. He then explains how the defendants' actions conformed with that industry standard.
Dr. Robert Nelson is qualified to offer expert testimony in this case. He is a clinical pharmacist by background and initial training. He also has a Masters in Science (Administration in Science and Technology) from George Washington University and a Ph.D. degree in epidemiology from the University of Minnesota.
He received his pharmacy degree in 1974 and completed a residency in Hospital and Clinical Pharmacy. Dr. Nelson then served as the clinical pharmacy liaison to the Neurology Institute at the National Institute of Health (NIH) until 1977, when he transferred to the Food and Drug Administration (FDA)'s Division of Neuropharmacological Drug Products. He continued working at the FDA for more than twenty years.
At the FDA, Dr. Nelson held various positions involving new drug review, epidemiology, and post-marketing surveillance. He was an Associate Director focusing on epidemiology. He also led a project to re-engineer the FDA's post-marketing surveillance program for human drugs, which included a comprehensive revision of the regulations and the construction and implementation of the database for spontaneous adverse event reports (AERs). Dr. Nelson was responsible for training all professional staff, including all medical reviewers, and was called upon to lecture and oversee the development of courses on drug regulation, regulatory science, statistics, clinical trial design, epidemiology, and pharmacokinetics.
Dr. Nelson has authored or co-authored over fifty publications, abstracts, and technical reports. He has presented on numerous occasions about new drug risk assessments, pharmacoepidemiology, regulatory decision-making, dose-response relationships, and good pharmacovigilance practices. He was elected to the initial class of 38 Fellows of the International Society for Pharmacoepidemiology (ISPE). He has also served as an adjunct professor in pharmacoepidemiology at the University of Maryland School of Pharmacy Graduate Program for eight years (2000-08).
Dr. Nelson has since retired and currently serves as a part-time consultant in global drug safety, regulatory safety, drug abuse liability assessments, Good Pharmacovilgance Practices, forensic epidemiology, and regulatory affairs. McNeil itself hired him to consult with the company and assist with its preparation for the 2002 FDA Advisory Committee Meeting concerning the risks of acetaminophen hepatotoxicity.
Dr. Nelson has offered expert testimony in over thirty other cases and has been qualified as a pharmacovigilance and regulatory expert.
Dr. Nelson is qualified to offer his opinions in this case.
The defendants claim that Dr. Nelson is not qualified to offer his opinions because he is not a medical doctor, an expert in liver disease, or an expert in pharmacokinetics.
In order to prepare his opinions, Dr. Nelson extensively reviewed the defendants' internal company documents, regulatory filings, medical literature, clinical studies, and epidemiological studies. He also reviewed the available medical literature about acetaminophen toxicity (i.e., case reports, case series, epidemiological analyses, clinical trials, toxicology studies, and pharmacological studies).
The defendants argue that Dr. Nelson's opinions should be excluded as unreliable. They claim that Dr. Nelson's opinions are based on "nothing more than his personal beliefs and commentary." The defendants' argument implies that Dr. Nelson's methods are unreliable because they are not "scientific" or testable. Dr. Nelson is being called to testify as a pharmacovigilance and regulatory expert; this does not preclude his testimony nor require he use "scientific" techniques.
As an FDA regulator, Dr. Nelson would undertake a similar process; he would examine the totality of the evidence to determine whether a risk was "known," the magnitude of that risk, what actions could or should be taken to reduce the risk, and whether the drug company had undertaken risk reduction measures. Dr. Nelson then methodically described in detail how the regulatory framework regarding adverse event reporting was set up to ensure that potential risks were shared with the FDA and the public. Applying his knowledge of the AERs regulations, he then explained how the defendants' actions were not in conformity with these standards, pharmacovigilance practices, and industry standards.
From what has been provided, Dr. Nelson's methods were thorough, and they conformed with practices used by other pharmacovigilance and regulatory experts. The defendants' argument is unpersuasive.
The defendants take issue with Dr. Nelson's "rough calculations" about how many people may have died or been injured by acetaminophen toxicity, claiming they are unreliable. The defendants mischaracterize the purpose of these "rough calculations." These estimates are meant to analyze whether the known or possible incidence of acetaminophen hepatotoxicity amount to the "safety signal." These estimates are performed almost daily by the FDA and are consistent with well-known pharmacovigilance principles. Dr. Nelson's analysis on this point is meant to show what a reasonable drug company would do to carry out pharmacovigilance duties. An article co-authored by Dr. Kenneth Kwong, McNeil's Director of Pharmacovigilance, recognizes this as a method often used to assess risk by drug companies.
I see nothing inappropriate about Dr. Nelson's calculations given their purpose and the context within which they are used.
The defendants claim Dr. Nelson's opinions should be excluded because they are not based on reliable epidemiological evidence.
As the defendants point out in their briefing, no such statistically-significant study on acetaminophen hepatotoxicity exists.
I find the defendants' argument unpersuasive. While epidemiological studies can be valuable evidence of causation, they are not a pre-requisite for product liability causation expert testimony.
The defendants also argue that Dr. Nelson's opinions are inadmissible as legal conclusions.
Dr. Nelson can, however, offer testimony on what certain technical regulatory documents mean and how they exemplify compliance with industry standards/customs.
As the Third Circuit noted, an expert's testimony in explaining industry standards may come close to the line of what is acceptable. I see nothing in Dr. Nelson's proffered testimony that warrants outright exclusion on these topics. However, I expect that his testimony will remain within the scope of his role as a pharmacovigilance and regulatory expert.
The defendants argue that Dr. Nelson's opinions are "broad and vague," making them "useless" to the jury. The sentences with which the defendants take issue are in the "conclusions" section of Dr. Nelson's report.
The defendants argue the Dr. Nelson's opinions related to "public health" are irrelevant or highly prejudicial. They claim that the defendants owe no duty to the public, only the plaintiff and decedent, and to indicate otherwise could be confusing to the jury. The plaintiff responds that duties to the public are relevant because Ms. Hayes was a member of the public. Any duties owed to the consumers generally would also have been owed to Ms. Hayes. This is a fair point.
In addition, the plaintiff points out that FDA documents about acetaminophen hepatotoxicity have noted it as a "public health problem." Dr. Nelson's discussing it as such would be relevant to provide background for his opinions. Lastly, the plaintiff explains that examining the "public health impact" of a drug is a part of good pharmacovigilance practices.
I see nothing inappropriate about Dr. Nelson's discussing of public health. The defendants' arguments go to weight, not admissibility.
The defendants argue that Dr. Nelson's opinions are preempted by
For the foregoing reasons, I will
An appropriate order follows.
FED. R. EVID. 702.
The plaintiff claims that Dr. Nelson may offer opinions related to the monograph system of regulation. From what has been provided, Dr. Nelson is not an expert in this very unique regulatory scheme. He may offer basic facts about the monograph system, in order to provide context, but he is not qualified to offer opinions to help the jury interpret the monograph regulations.
The defendants' interpretation of the type of association needed before using Bradford-Hill is overstated. There is nothing to say that a statistically-significant association must be found before applying the methodology. In fact, the whole point of using the Branford-Hill methodology is to test an observational association to show causation.
Dr. Nelson offers observational, epidemiological data to show an association between acetaminophen and hepatotoxicity. He then meticulously applies the Bradford-Hill guidelines to the available epidemiological data. From what has been provided, he appears to use the methodology reliably.
Dr. Nelson does not rely solely on case reports in rendering his opinion. The case reports and case series he does cite also include controls on the information analyzed, which make them more reliable.
In addition, case reports and case series are the types of information on which DILI experts often rely.
Whether the case reports themselves may be admissible or disclosed to the jury is a separate question, which I will defer until I see how they may be used at trial.
As explained above, epidemiological or case-controlled studies for acetaminophen-induced liver injuries are not available. In the absence of epidemiological data, case reports and case series serve as valuable sources of information for DILI experts, doctors, and scientists in determining causation.
I note that the way acetaminophen has been regulated—having been on the market, grandfathered in under the monograph system, and never issued a final monograph—may also explain why this type of research has never been conducted.
The defense experts admit that having case-controlled epidemiological data is not a requirement in finding causation for drug-injured liver injuries.