Dealing With Expert Opinion Based On “Adverse Event Reports” (AERs)

In diversity medical-product liability suit, admitting under FRE 702 plaintiff's expert's testimony that the charged drug adversely affected the plaintiff's medical condition, causing "hypersensitivity reaction[s]" as a result of its defective design; the expert opinions were based on relevant factors for assessing drugs (such as number of FDA adverse report events) and any biases that might affect the interpretation of the data were not so overwhelming as to render the opinion unreliable and any distortion went to the weight, not admissibility, in Bartlett v. Mutual Pharmaceutical Co., Inc., __ F.3d __ (1st Cir. May 2, 2012) (No. 10–2277)

In the case, plaintiff Bartlett sued defendant Mutual alleging she suffered an adverse reaction (hypersensitivity manifested by Stevens-Johnson Syndrome and toxic epidermal necrolysis - "SJ/TEN") from taking their medication "Sulindac" - a NAISD. She alleged that over 30% of her outer skin layer had deteriorated as a result of the medication. The jury that heard her case agreed and awarded the plaintiff $21.06 million in compensatory damages. The defendant appealed, basing part of its argument of the admission of testimony by plaintiff's expert on pharmacology and toxicology.

One ground the defendant advanced in the appeal was the contention that the expert testimony lacked a "scientific basis" that rendered it reliable under FRE 702. This concerned the experts' assessment of the risks and benefits of the defendant's drug. As noted by the circuit, the trial court allowed the plaintiff's experts:

-to opine that sulindac's overall risk/benefit profile was unfavorable for marketing
-to opine that aspirin and acetaminophen, which have no known connection to SJS/TEN, are safer alternatives to sulindac
-to discuss voluntary “adverse event reports” (AERs) from prescribing doctors to the FDA, and the limitations of such data
-to opine—based on the number of AERs and an estimated number of sulindac prescriptions-on the “reporting rate” of SJS/TEN, and to compare drugs' reporting rates
-to offer various opinions about the inadequacy of sulindac's warning to counteract its dangerousness -
and to opine that the FDA lacks the resources to ensure that all marketed drugs are safe and effective.
Bartlett, __ F.3d at __.

The defendant contended that these opinions should not have been admitted because they were based upon the experts' use of the agency's AER (Adverse Event Report)s. The AERs were "voluntary reports from medical professionals and consumers to the FDA regarding patients' adverse reactions to pharmaceuticals." The defendant objected to the plaintiff's experts use of this data because there was

"no quality controls on [these] spontaneous reports; that various biases may increase reporting, including increased reporting following introduction of a new warning (a phenomenon called the “Weber effect”); and the difficulty of determining the number of total prescriptions (“denominator data”) to determine a reporting rate. The FDA itself warns that “[a]ccumulated case reports cannot be used to calculate incidence or estimates of drug risk.” Mutual also argues there is no accepted methodology for comparing drugs based on adverse event data.
Bartlett, __ F.3d at __.

The circuit acknowledged that there were "various shortcomings in adverse event data." But these shortcomings were not fatal to the plaintiff's case against the defendant. In the case of the AERs, the circuit noted that this often-times weak data was the only data available. The reports were "part of the calculus [of,] and surely relevant input for[,] a witness who is prepared to opine on the risk-benefit ratio" of the charged drug. For example, the use of the AERs was so pervasive that even the defendant's "own designated expert['s opinions] ... relied on adverse event data and comparative reporting rates in a peer-reviewed publication designed to quantify the risk of SJS/TEN associated with the use" of NSAIDs such as the defendant's drug.

In addition, even "the FDA itself considered the SJS/TEN reporting rate" in examining a similar drug that had been withdrawn based on a "published ... study comparing SJS/TEN reporting rates among certain NSAIDs." Bartlett, __ F.3d at __. Often the expert had to use what data was available, despite its infirmities. Here, where both the government regulator and the defendant's expert depended on use of AERs. There could be little basis for objecting to the plaintiff expert's use of similar data to assess similar issues.

Ultimately the circuit noted that dealing with conceptual shortcomings of the data used in the field did not support excluding the opinions based on that data. Rather, where the data is of use in the field, the weaknesses of the data is not for the court to screen out in advance. Rather, whatever the deficiencies were in the data, if it was not completely lacking in relevance, the opponent of it "was free to—and did—highlight the flaws on cross-examination" of the experts utilizing the data. Bartlett, __ F.3d at __.

Illustration: Sulindac Chemical Structure


Federal Rules of Evidence