United States: Clean Sweep Of Plaintiffs' Causation Experts In Gadolinium Litigation

Last Updated: August 14 2019
Article by Michelle Yeary

Today we bring you a terrific Daubert defense win. But, we'll be honest it's long. Really long. Thorough, but long. So, we're going to hit the highlights.

The case is Davis v. McKesson Corp., 2019 WL 3532179 (D. Ariz. Aug. 2, 2019). It is a multi-plaintiff case against manufacturers and distributors of gadolinium-based contrast agents ("GBCA") – used in MRIs. GBCAs were the subject of an MDL several years involving allegations that when administered to patients with advanced kidney disease they caused a disease known as nephrogenic systemic fibrosis ("NSF"). Id. at *2. Plaintiffs in the current action allege that they have been exposed to GBCAs but that they do not have impaired kidneys and they have not been diagnosed with NSF. Rather, they contend that after receiving GBCAs they developed "a range of symptoms [that] has not been recognized as a disease by regulatory authorities or medical associations, but the collection of symptoms has been referred to in some literature as "gadolinium deposition disease" ("GDD"). Id. In fact, the FDA convened an advisory committee in 2017 to explore the very issue of any connection between the retention of GBCAs in the body and the various symptoms reported by patients with healthy kidneys. The board "unanimously concluded that the medical and scientific evidence does not establish that GBCAs cause GDD." Id. at *6. Many other foreign regulatory bodies and medical societies have reached the same conclusion. Id.

So, the court decided that the issue of general causation should be decided first and plaintiffs served expert reports from four experts, three on medical causation. And if we had to sum it all up, what plaintiffs' experts offer are "theories" or "hypotheses" – that still need to be tested – but are not reliable science that establish that the symptoms associated with GDD are an actual illness or that the illness is caused by GCBAs. Id. at *10. But, the court provides a lot more detail.

For instance, one of plaintiffs' experts' opinions is that GBCAs cause a "continuum" of symptoms the most severe of which cause NSF in renal impaired patients and less severe symptoms in patients with healthy kidneys. Id. at *11. This would basically impute the general medical causation of NSF to GDD because they are simply different ends of the same continuum. "But this leap rests on nothing more than [plaintiff's expert's] say so." Id. at *12.

Plaintiffs try to bridge the gap by relying on case reports and surveys – the experiences of single patients without a formal study or control group. Id. at *14. But, "case reports are not reliable scientific evidence of causation," id. at *14, and "[s]urveys are even less reliable." Id. at *15. At least some case reports are made by physicians, whereas surveys "consist of unscreened answers from people who believe they suffer from GBCA-caused illnesses, often provided anonymously." Id. All of plaintiffs' causation experts relied on both case reports and surveys with no acknowledgement of their limitations.

From there, plaintiffs' experts moved on to animal studies which while not inadmissible, "there must be a basis for extrapolating them to the human population." Id. at *16. Plaintiffs' experts did not provide any such basis. In fact, several of the animal studies plaintiffs' experts relied on involved rodents whose kidneys had been removed – making them less relevant to plaintiffs' allegations that GBCAs cause GDD in humans with healthy kidneys. Id. The connection between the animal studies and plaintiffs' experts' opinions is based only on the experts' "say-so." Id. at *17.

Plaintiffs' experts similarly cite in vitro studies but do not discuss "the doses used in the studies or explain[] how those doses can reliably be extrapolated to the effects of GBCAs in humans with healthy kidneys." Id. Further, plaintiffs' experts' "principles and methods for finding GBCA causation of GDD have not been accepted by other experts, regulatory bodies, or professional associations" and at least two of the experts "have not done [independent] research and their opinions appear to have been prepared solely for this litigation." Id. Indeed, one of plaintiffs' experts was a keynote speaker at the FDA advisory board where "he made several statements quite inconsistent with his current opinions" but nowhere in his report does he cite any data to support his changed opinions. Id. at *25-26.

The bulk of the rest of the decision is filled with example after example of the specific ways in which plaintiffs' experts fail in each of the above ways to satisfy the standard for admissibility under Daubert and Rule 702. For instance:

  • Plaintiffs' expert "never explains why the transfer of gadolinium from pregnant mice to their pups, or the accidental injection of GBCAs into the spinal canals of patients, or two case reports with their wide and differing range of symptoms can, through reliable scientific principles and methods, be extrapolated to show that GBCAs cause GDD in patients with healthy kidneys." at *19
  • Plaintiffs' expert "does not explain how the in utero exposure relates to patients with healthy kidneys, nor does he address why the in vitro study of skin growth, and its doses, can be reliably extrapolated to humans with no renal impairment." at *22.
  • Plaintiffs' expert "does not explain why case reports from NSF patients can reliably be applied to reach any conclusions, including conclusions regarding patients who have healthy kidneys and do not have NSF; why the use of a survey or the effects on a dog can be applied reliably to the same patients; or, for that matter, why heart, respiratory, and liver effects have anything to do with Plaintiffs, none of whom claim such ill effects."
  • Plaintiffs' expert "cites no evidence that retention in patients with normal renal function is equal in method or quantity to the accumulation in renally-impaired patients, and he merely assumes as probable that 'tissue injury that occurs from GBCAs in renally impaired patients shares the same mechanisms of toxic injury with patients who have normal kidney function.'" Id. at *30.
  • Plaintiffs' expert "offers only one-line conclusions summarizing the results of these studies with no explanation about why these studies can reliably be applied to the causation issue in this case or how they relate to his opinions." at *31.

And then there is plaintiffs' experts' application of the Bradford Hill criteria. The Bradford Hill criteria are used by epidemiologists in differentiating between a mere association and a causal connection. While the court conducts a thorough analysis of all nine criteria, we really only need to examine the first one – strength of association. An observed association is the starting point for the Bradford Hill analysis. And the association that starts the analysis is normally an epidemiologic study – which plaintiffs admit doesn't exist for the relation between GBCAs and GDD. Id. at *33. At best plaintiffs' experts can cite the causal link between GBCA and NSF, but that doesn't establish a relationship to GDD – and you can't assume a relationship. Id.

Finally, the court explains why plaintiffs' case law doesn't save their argument. First, plaintiffs rely on Wendell v. GlaxoSmithKline, LLC, 858 F.3d 1227 (9th Cir. 2017) – one of our worst decisions that year and discussed in more detail here. Fortunately, the court quickly distinguished it as a specific causation case and while we think there are many more reasons not to follow it, we'll take it. Davis, at *44-45. Second, plaintiffs tried to analogize to the Daubert decision in the NSF MDL, but for all the reasons plaintiffs' experts couldn't rely on NSF science, the court wasn't going to rely on NSF law. Id. at *45.

The court gave the parties two weeks to submit a "plan" for what happens next. Without an expert on general causation, the only route we see as viable is dismissal.

This article is presented for informational purposes only and is not intended to constitute legal advice.

To print this article, all you need is to be registered on Mondaq.com.

Click to Login as an existing user or Register so you can print this article.

Similar Articles
Relevancy Powered by MondaqAI
In association with
Related Topics
Similar Articles
Relevancy Powered by MondaqAI
Related Articles
Related Video
Up-coming Events Search
Font Size:
Mondaq on Twitter
Mondaq Free Registration
Gain access to Mondaq global archive of over 375,000 articles covering 200 countries with a personalised News Alert and automatic login on this device.
Mondaq News Alert (some suggested topics and region)
Select Topics
Registration (please scroll down to set your data preferences)

Mondaq Ltd requires you to register and provide information that personally identifies you, including your content preferences, for three primary purposes (full details of Mondaq’s use of your personal data can be found in our Privacy and Cookies Notice):

  • To allow you to personalize the Mondaq websites you are visiting to show content ("Content") relevant to your interests.
  • To enable features such as password reminder, news alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our content providers ("Contributors") who contribute Content for free for your use.

Mondaq hopes that our registered users will support us in maintaining our free to view business model by consenting to our use of your personal data as described below.

Mondaq has a "free to view" business model. Our services are paid for by Contributors in exchange for Mondaq providing them with access to information about who accesses their content. Once personal data is transferred to our Contributors they become a data controller of this personal data. They use it to measure the response that their articles are receiving, as a form of market research. They may also use it to provide Mondaq users with information about their products and services.

Details of each Contributor to which your personal data will be transferred is clearly stated within the Content that you access. For full details of how this Contributor will use your personal data, you should review the Contributor’s own Privacy Notice.

Please indicate your preference below:

Yes, I am happy to support Mondaq in maintaining its free to view business model by agreeing to allow Mondaq to share my personal data with Contributors whose Content I access
No, I do not want Mondaq to share my personal data with Contributors

Also please let us know whether you are happy to receive communications promoting products and services offered by Mondaq:

Yes, I am happy to received promotional communications from Mondaq
No, please do not send me promotional communications from Mondaq
Terms & Conditions

Mondaq.com (the Website) is owned and managed by Mondaq Ltd (Mondaq). Mondaq grants you a non-exclusive, revocable licence to access the Website and associated services, such as the Mondaq News Alerts (Services), subject to and in consideration of your compliance with the following terms and conditions of use (Terms). Your use of the Website and/or Services constitutes your agreement to the Terms. Mondaq may terminate your use of the Website and Services if you are in breach of these Terms or if Mondaq decides to terminate the licence granted hereunder for any reason whatsoever.

Use of www.mondaq.com

To Use Mondaq.com you must be: eighteen (18) years old or over; legally capable of entering into binding contracts; and not in any way prohibited by the applicable law to enter into these Terms in the jurisdiction which you are currently located.

You may use the Website as an unregistered user, however, you are required to register as a user if you wish to read the full text of the Content or to receive the Services.

You may not modify, publish, transmit, transfer or sell, reproduce, create derivative works from, distribute, perform, link, display, or in any way exploit any of the Content, in whole or in part, except as expressly permitted in these Terms or with the prior written consent of Mondaq. You may not use electronic or other means to extract details or information from the Content. Nor shall you extract information about users or Contributors in order to offer them any services or products.

In your use of the Website and/or Services you shall: comply with all applicable laws, regulations, directives and legislations which apply to your Use of the Website and/or Services in whatever country you are physically located including without limitation any and all consumer law, export control laws and regulations; provide to us true, correct and accurate information and promptly inform us in the event that any information that you have provided to us changes or becomes inaccurate; notify Mondaq immediately of any circumstances where you have reason to believe that any Intellectual Property Rights or any other rights of any third party may have been infringed; co-operate with reasonable security or other checks or requests for information made by Mondaq from time to time; and at all times be fully liable for the breach of any of these Terms by a third party using your login details to access the Website and/or Services

however, you shall not: do anything likely to impair, interfere with or damage or cause harm or distress to any persons, or the network; do anything that will infringe any Intellectual Property Rights or other rights of Mondaq or any third party; or use the Website, Services and/or Content otherwise than in accordance with these Terms; use any trade marks or service marks of Mondaq or the Contributors, or do anything which may be seen to take unfair advantage of the reputation and goodwill of Mondaq or the Contributors, or the Website, Services and/or Content.

Mondaq reserves the right, in its sole discretion, to take any action that it deems necessary and appropriate in the event it considers that there is a breach or threatened breach of the Terms.

Mondaq’s Rights and Obligations

Unless otherwise expressly set out to the contrary, nothing in these Terms shall serve to transfer from Mondaq to you, any Intellectual Property Rights owned by and/or licensed to Mondaq and all rights, title and interest in and to such Intellectual Property Rights will remain exclusively with Mondaq and/or its licensors.

Mondaq shall use its reasonable endeavours to make the Website and Services available to you at all times, but we cannot guarantee an uninterrupted and fault free service.

Mondaq reserves the right to make changes to the services and/or the Website or part thereof, from time to time, and we may add, remove, modify and/or vary any elements of features and functionalities of the Website or the services.

Mondaq also reserves the right from time to time to monitor your Use of the Website and/or services.


The Content is general information only. It is not intended to constitute legal advice or seek to be the complete and comprehensive statement of the law, nor is it intended to address your specific requirements or provide advice on which reliance should be placed. Mondaq and/or its Contributors and other suppliers make no representations about the suitability of the information contained in the Content for any purpose. All Content provided "as is" without warranty of any kind. Mondaq and/or its Contributors and other suppliers hereby exclude and disclaim all representations, warranties or guarantees with regard to the Content, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. To the maximum extent permitted by law, Mondaq expressly excludes all representations, warranties, obligations, and liabilities arising out of or in connection with all Content. In no event shall Mondaq and/or its respective suppliers be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use of the Content or performance of Mondaq’s Services.


Mondaq may alter or amend these Terms by amending them on the Website. By continuing to Use the Services and/or the Website after such amendment, you will be deemed to have accepted any amendment to these Terms.

These Terms shall be governed by and construed in accordance with the laws of England and Wales and you irrevocably submit to the exclusive jurisdiction of the courts of England and Wales to settle any dispute which may arise out of or in connection with these Terms. If you live outside the United Kingdom, English law shall apply only to the extent that English law shall not deprive you of any legal protection accorded in accordance with the law of the place where you are habitually resident ("Local Law"). In the event English law deprives you of any legal protection which is accorded to you under Local Law, then these terms shall be governed by Local Law and any dispute or claim arising out of or in connection with these Terms shall be subject to the non-exclusive jurisdiction of the courts where you are habitually resident.

You may print and keep a copy of these Terms, which form the entire agreement between you and Mondaq and supersede any other communications or advertising in respect of the Service and/or the Website.

No delay in exercising or non-exercise by you and/or Mondaq of any of its rights under or in connection with these Terms shall operate as a waiver or release of each of your or Mondaq’s right. Rather, any such waiver or release must be specifically granted in writing signed by the party granting it.

If any part of these Terms is held unenforceable, that part shall be enforced to the maximum extent permissible so as to give effect to the intent of the parties, and the Terms shall continue in full force and effect.

Mondaq shall not incur any liability to you on account of any loss or damage resulting from any delay or failure to perform all or any part of these Terms if such delay or failure is caused, in whole or in part, by events, occurrences, or causes beyond the control of Mondaq. Such events, occurrences or causes will include, without limitation, acts of God, strikes, lockouts, server and network failure, riots, acts of war, earthquakes, fire and explosions.

By clicking Register you state you have read and agree to our Terms and Conditions