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European Medicines Agency takes action on Linear Gadolinium-based Contrast Agents
On July 21, 2017, the European Medicines Agency (EMA) confirmed previous recommendations to suspend the use of three linear gadolinium-based contrast agents (GBCAs) used for MRIs, citing potential risks from brain deposition of gadolinium. The use of one other linear GBCA will be restricted to liver scans.
The 3 suspended agents are Magnevist (gadopentetic acid), Omniscan (gadodiamide), and OptiMark (gadoversetamide). The agent restricted to liver scans is MultiHance (gadobenic acid).
Read the article on Aunt Minne about this action here:
http://www.auntminnie.com/index.aspx?sec=ser&sub=def&pag=dis&ItemID=117859
The official announcement from the EMA can be found here:
http://www.ema.europa.eu/docs/en_GB/document_library/Referrals_document/gadolinium_contrast_agents_31/Opinion_provided_by_Committee_for_Medicinal_Products_for_Human_Use/WC500231824.pdf
Additional information on the EMA website can be found here:
http://www.ema.europa.eu/ema/index.jsp?curl=pages/medicines/human/referrals/Gadolinium-containing_contrast_agents/human_referral_prac_000056.jsp&mid=WC0b01ac05805c516f
We are encouraged by the EMA’s action and believe that the FDA should take a similar stance.
Patients and their doctors should report all adverse events and clinical symptoms to the FDA or the appropriate governing authority in their country. Chronic symptoms that develop soon after MRIs with contrast could be manifestations of the harm done by gadolinium deposition in the brain, bones, and elsewhere in the body.
Open Letter to the FDA about Gadolinium-based Contrast Agents
Editorial – May 25, 2017
Sharon Williams
I am very disappointed and frustrated by the May 22, 2017, FDA Safety Announcement about gadolinium-based contrast agents (GBCAs). I am beginning to wonder how many more people must be adversely affected by retained gadolinium before the FDA decides to take decisive action.
Personally, I don’t blame the FDA or radiologists for what happened to NSF patients. What happened to those patients was terrible, but I want to believe that no one knew then just how unstable the linear agents are, especially when they remain in the body for longer periods of time like they might do in renally-impaired patients. However, once the connection between NSF and GBCAs was discovered in 2006, that all began to change. No longer could the FDA and radiology community say that they didn’t know that gadolinium might be retained from MRI contrast agents or what it might do to the human body when that occurred.
From 2006 until the end of 2013, the FDA and medical community thought that only patients with severe renal problems were at risk of retaining gadolinium. Warnings were issued and action was taken to better screen renally-impaired patients and reports of new cases of Nephrogenic Systemic Fibrosis (NSF) dropped dramatically. However, no one seemed to be investigating what might happen when less gadolinium was retained such as what might occur in patients with “normal” renal function or eGFRs greater than 60.
Since December of 2013 and the first paper by Kanda and his colleagues, the evidence has been mounting that clearly shows that patients with normal renal function retain gadolinium in their brains, bones, and elsewhere in their bodies. This seemed to be news to the FDA and radiology community, but it was something that patients affected by gadolinium have long been trying to tell their doctors. I first brought it to the attention of the FDA in my letter of October 23, 2012. In that letter, I noted that evidence of gadolinium retention in patients with normal renal function was reported by Gibby et al. in 2004 – that was 13 years ago, and it occurred after administration of both a linear and a macrocyclic GBCA.
The published literature clearly states that “gadolinium is toxic”. The FDA has acknowledged that “all GBCAs may be associated with some gadolinium retention in the brain, and other body tissues”. So why is it okay to keep injecting the least stable gadolinium-based contrast agents into patients when it is highly likely that those people are going to retain some unknown amount of a toxic metal? Gadolinium is a toxic metal that has been found to be neurotoxic, to impair mitochondrial function, induce oxidative stress, and much more. Researchers are looking for histological changes in the brain, but what about functional changes? (more…)
European group recommends to stop using 4 linear GBCAs
March 10, 2017 – A committee of the European Medicines Agency (EMA) has recommended the suspension of the marketing authorizations for four linear gadolinium-based contrast agents (GBCAs) used for MRI scans because of concerns about small amounts of gadolinium from administered GBCAs being deposited in the brain.
At the completion of its year-long review of GBCAs, the EMA’s Pharmacovigilance and Risk Assessment Committee (PRAC) “found convincing evidence of accumulation of gadolinium in the brain from studies directly measuring gadolinium in brain tissues and areas of increased signal intensity seen on MRI scan images many months after the last injection of a gadolinium contrast agent”.
Linear agents recommended for suspension by the PRAC are:
Gadobenic acid, marketed as MultiHance by Bracco Diagnostics Inc.
Gadodiamide, marketed as Omniscan by GE Healthcare
Gadopentetic acid, marketed as Magnevist by Bayer HealthCare Pharmaceuticals
Gadoversetamide, marketed as OptiMARK by Mallinckrodt Inc.
The PRAC’s final recommendations will be sent to the Committee for Medicinal Products for Human Use (CHMP) for its opinion. Further details will be published when CHMP renders its opinion regarding the removal of the four linear agents from the market.
In its press release, the PRAC noted that deposition of gadolinium in other organs and tissues has been associated with rare side effects of skin plaques and Nephrogenic Systemic Fibrosis (NSF). It also noted that “non-clinical laboratory studies have shown that gadolinium can be harmful to tissues”.
The PRAC said that two linear agents will remain available: gadoxetic acid (brand name Eovist), used at a low dose for liver scans, since it meets an important diagnostic need in patients with few alternatives, and a formulation of gadopentetic acid injected directly into joints because its gadolinium concentration is very low. The PRAC indicated that both agents should be used at “the lowest dose that enhances images sufficiently to make diagnoses and only if unenhanced scans are not suitable”.
FDA actions
On July 27, 2015, the FDA issued its first, and so far only, Safety Announcement regarding gadolinium retention in the brain following repeated use of a GBCA for MRIs. It acknowledged that trace amounts of gadolinium may stay in the body long-term, and noted that “recent studies conducted in people and animals have confirmed that gadolinium can remain in the brain, even in individuals with normal kidney function”.
The 2015 announcement said that the FDA, including its National Center for Toxicological Research (NCTR), “will study this possible safety risk further”. As of this writing, the FDA has made no further public safety announcements regarding the use of gadolinium-based contrast agents.
It remains to be seen if the FDA will follow the lead of the EMA and suspend the use of the linear GBCAs. Three of the four suspended agents are linked to the most unconfounded cases of NSF, and they are among the most widely used GBCAs for magnetic resonance imaging (MRI) procedures.
Sharon Williams
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PRAC concludes assessment of gadolinium agents used in body scans and recommends regulatory actions, including suspension for some marketing authorisations. EMA/157486/2017. http://www.ema.europa.eu/docs/en_GB/document_library/Press_release/2017/03/WC500223209.pdf
New Study Reports Gadolinium Retention in 70 Cases with Normal Kidney Function
Full-disclosure, we are reporting on our own retention paper.
Today we have released our fourth research paper on gadolinium retention from Gadolinium-based Contrast Agents (GBCAs) administered for contrast-enhanced MRIs. The paper is titled “Gadolinium Retention from Contrast MRIs in 70 Cases with Normal Renal Function – 24-hour Urine Test Results”.
Drawing on the contrast MRI history and 24-hour gadolinium urine testing results information that we have received from members of the MRI-Gadolinium-Toxicity Support Group, we reported retrospectively on 70 cases with 120 urine test results. We are thankful to the members of our support group for being willing to share their information with us. The participants all had normal kidney function and report having symptoms of gadolinium toxicity. We believe the results reported are dramatic.
About the Gadolinium Retention Study
The number of results presented is up significantly from our last paper in 2014 when we reported on 15 cases and 40 test results. The additional data points allowed us to look at gender as a possible differentiator, but the data showed nearly identical test results for males and females. With information about the number of contrast-enhanced MRIs for each case, we were able to analyze the results in three groups: cases with a single contrast MRI, cases with 2 to 4 contrast MRIs, and cases with 5 or more contrast MRIs. Readers of this site will not be surprised that the analysis showed that for these cases, there was a discernible difference in test results based on these groupings. The 2 to 4 contrast group generally had higher levels of gadolinium in their urine for a longer period of time than those with a single contrast. Likewise, the results for the 5 or more MRIs group were higher longer than the cases in the 2-4 contrast MRIs group. This is consistent with the cumulative effect of multiple contrast-enhanced MRIs that others have reported.
We also provided the raw test results data for each case, enabling other researchers as well as patients to look at the progression of test results over time. Averages for time blocks since the last contrast MRI are also shown to help in understanding the progression of gadolinium urine levels.
A few observations regarding the test results are revealing. 21 cases had urine tests performed in the first month with results that range from 507 mcg Gd/24hr urine specimen 4 days after the contrast MRI to results around 17 mcg Gd/24hr near the end of the first month. All of the results are enumerated in the report. 8 cases had urine test results more than 36 months after their contrast MRI with results as high as 0.6 mcg Gd/24hr more than 7 years after the individual’s last contrast-enhanced MRI. There is no broadly utilized acceptable range for gadolinium in a 24-hour urine collection. Mayo Clinic has established a reference range that was recently updated to be 0.0-0.6 mcg Gd/24-hour urine specimen collected more than 96 hours after administration of a GBCA. 40 cases had urine tests in the first 3 months after their contrast MRI, with the lowest result being 1.74 mcg Gd/24hr, well above the Mayo reference range that is applicable once four days have elapsed since the contrast MRI. Simply stated the results we observed are inconsistent with the clearance times indicated on GBCA product labeling and the understanding of most researchers and clinical practitioners.
Final Thoughts
To the best of our knowledge, this is the most comprehensive reporting of retained gadolinium as evidenced by urine testing that is available to the public. While the methods we used do not meet the rigor of a clinical trial, and we do not know if similar results would be seen universally, we believe the consistency of the results and the lack of outliers on the low side are justification for concern. We believe that further investigation by researchers, GBCA manufacturers, and licensing agencies is warranted.
This study does not stand alone, but confirms the many recently published research papers that reported unexpected retention of gadolinium from contrast MRIs by people with normal renal function. We encourage stronger action by the FDA and others to inform patients about possible gadolinium retention from contrast-enhanced MRIs and the potential for long-term side-effects.
We urge patients, clinicians, and researchers to read the entire report and share as appropriate with your families, care-givers, and colleagues. Read the Report.
Hubbs Grimm and Sharon Williams
Gadolinium Toxicity 