News & Events
U.S. Food and Drug Administration Threatens Enforcement Action over Desiccated Thyroid Extract (DTE) Products
by Kimberly Dorris, GDATF Executive Director
This has been a rapidly evolving situation – please bookmark this page and check back for updates! The newest updates are included at the top of this post. For important history and context on this issue, scroll down to the section titled “Original Blog Post”.
11/6/25 10:45 a.m. PST – Congressman Abe Hamadeh has released a statement calling on the FDA to “Cease Enforcement Action” on desiccated thyroid extract. Parts of the letter are politically charged, but we are sharing here because of the relevance to the thyroid community. It’s also important to note that the FDA has taken critical enforcement action against bad actors over the last few months to ensure public safety.
11/6/25 8:50 a.m. PST – Here’s a non-paywalled article from Robert Alexander at Newsweek that has details on the lawsuit.
11/5/25 9:05 a.m. PST – See below for highlights of the AURINIA PHARMACEUTICALS INC., and AURINIA PHARMA U.S., INC. v. GEORGE F. TIDMARSH lawsuit. The full documentation is available on CourtListener, and you can access the main filing and exhibits here. As a reminder, while these allegations are incredibly serious, both parties will have an opportunity to present their case in a court of law.
[EDIT: Much of the lawsuit focuses on voclosporin, a drug used to treat active lupus nephritis. The highlights below only include only the portions relevant to desiccated thyroid extract.]
A. The lawsuit alleges that animosity between Dr. George Tidmarsh and Kevin Tang (Chairman of the Board of Aurinia and American Laboratories) dates back to 2019, when Tang asked Dr. Tidmarsh to resign his positions at American Laboratories and other Tang-controlled companies. American Laboratories produces the Active Pharmaceutical Ingredient used in desiccated thyroid extract (DTE) products.
B. The exhibits include screen shots of emails and text exchanges between Tidmarsh and Tang dating back to 2019 that are unrelated to DTE. On November 29, 2024, Tidmarsh emailed Tang stating, “sending this one last time before we end up in a negative situation. please respond” (see Exhibit 7).
C. Exhibit 8 is the LinkedIn post from Tidmarsh regarding desiccated thyroid extract, which was originally posted on November 30, 2024 (and which came to light after the FDA announcement on DTE). The post reads, “The new FDA needs to remove harmful, useless drugs from the market. Let’s start with desiccated thyroid extract. An unapproved, crude pig tissue extract that is proven worse than synthetic hormone and harmful. Working with the new FDA to remove it permanently from the market.”
For context (and not mentioned in the lawsuit), the announcement that Dr. Martin Makary had been nominated to lead the U.S. FDA came on November 22, 2024.
D. Exhibit 9 is a screen shot of an email from Tidmarsh to Tang, sent on November 30, 2024. The email contains no text, except for a hyperlink to the LinkedIn post. The subject line of the email is “Good Luck”.
E. Exhibit 10 is a screen shot of another email from Tidmarsh to Tang, this one dated December 10, 2024. The subject line is “What in the world is wrong with you?” and the text states, “I’ve have [sic] made a simple request for you to communicate with me yet you have not. I’m Not powerless.” (Exhibit 10)
F. On July 21st, Dr. Tidmarsh was named as Director of the FDA’s Center for Drug Evaluation and Research (CDER).
G. This is not mentioned in the lawsuit, but CDER is one of two drug divisions at the FDA. The other is the Center for Biologics Evaluation and Research (CBER), which at the time was headed by Dr. Vinay Prasad. This is important because desiccated thyroid extract is currently considered a “biologic” drug (although there is controversy over whether this is appropriate) and thus falls under CBER leadership. Dr. Prasad resigned his post on July 30, 2025, and in his absence, Dr. Tidmarsh became acting head of CBER. (Prasad returned as CBER head on August 11, 2025.)
H. The lawsuit alleges that Dr. Tidmarsh was still receiving payments under a “services agreement” with American Laboratories and that on July 31st, the attorney for Dr. Tidmarsh contacted American Laboratories to redirect future payments to a separate entity (also controlled by the attorney, but for the benefit of Tidmarsh’s three sons) in order to meet legal requirements for divestiture.
I. As is publicly known, on August 6th, 2025, the FDA sent letters to manufacturers, importers, and distributors stating that DTE products required an approved biologics license application, and after a 12-month transition period, the FDA would “initiate action against manufacturers, distributors, and importers of ADT and unapproved ADT products intended for commercial distribution.” On August 7th, the FDA made a public announcement. Notably, the process for filing a BLA and gaining approval can take longer than 12 months. The rest of the publicly available information is reported elsewhere in this blog post. Notably, FDA commissioner Makary posted on social media on August stating that the FDA would “ensure continued access”, yet the August 6th letters and August 7th announcement have never been rescinded, and until we get clarity, it appears that the 12-month timeline is now down to 9 months.
J. On August 28th, a lawyer for Dr. Tidmarsh emailed Tang about the “services agreement”, stating, “It is my understanding that ALI [American Laboratories] may have issues that require an extension of the services agreement. Accordingly, we propose to extend the services agreement for another 10 years.” (Exhibit 12)
K. The lawsuit alleges that Tang contacted law enforcement and emailed the attorney for Tidmarsh on September 4, 2025, asking the attorney to clarify precisely “what issues [Dr. Tidmarsh] can help with.” Galda, the attorney, did not respond until October 31, 2025, when he emailed Tang stating that “to be clear,” Dr. Tidmarsh could not provide any assistance “in his capacity with the FDA.” Galda accused Tang
of inappropriately “soliciting” Dr. Tidmarsh’s assistance with American Laboratories and stated that this might “require a referral to the appropriate authorities.” (Exhibit 13) [End of Update]
11/4/25 3:55 p.m. PST – A copy of the AURINIA PHARMACEUTICALS INC., and AURINIA PHARMA U.S., INC. v. GEORGE F. TIDMARSH lawsuit is now available on CourtListener. You can access the main filing and exhibits here. We have a Zoom support group meeting starting soon (if you are interested in Zoom support groups, fill out our contact form here), but check back on Wednesday for highlights. These allegations are explosive – but of course, will have to be proven in a court of law.
11/4/25 7:45 a.m. PST – Fraiser Kansteiner at Fierce Pharma has provided some non-paywalled detail regarding the lawsuit filed by Aurinia Pharmaceuticals against Dr. George Tidmarsh. While both parties to a lawsuit such as this will have an opportunity to make their case in a court of law, the accusations are, frankly, stunning. American Laboratories supplies the Active Pharmaceutical Ingredient for Armour Thyroid. From the linked article:
Aside from the Lupkynis LinkedIn post, Tidmarsh purportedly used his role at CDER to push the FDA to “effectively remove” desiccated thyroid extract (DTE) products from the U.S. market earlier this year, Aurinia’s lawyers argued. DTE products are used to treat hypothyroidism.
This move, which Aurinia’s legal team suggests was targeted, cut off a key source of income for the Tang-affiliated company American Laboratories, the lawsuit claims.
Tidmarsh then allegedly tried to leverage the situation to “extort and solicit a bribe from Mr. Tang in exchange for Dr. Tidmarsh using his power to reverse or otherwise mitigate the adverse impact on Mr. Tang, Tang Capital, and American Laboratories,” the suit continues.
11/3/25 – Dr. George Tidmarsh has resigned his post as the FDA’s Director of the Center for Drug Evaluation and Research (CDER) – and there’s an interesting connection with the FDA’s announcement targeting desiccated thyroid extract (DTE).
Tidmarsh was initially placed on leave (amid conflicting stories) but subsequently resigned on Sunday, in the wake of a lawsuit filed by Aurinia Pharmaceuticals. It’s important to note that both parties get to have their say in court when a lawsuit is filed, but Aurinia alleges that Tidmarsh used his FDA authority to target the chair of the company’s board of directors, Kevin Tang. Most of the media coverage regarding this lawsuit has focused on Dr. Tidmarsh’s since-deleted LinkedIn post on voclosporin (which is used to treat active lupus nephritis). However, you might also remember Dr. Tidmarsh from his 2024 LinkedIn comments about desiccated thyroid extract (which were posted months before his appointment as head of CDER).
And the lawsuit also alleges that Tidmarsh targeted a “thyroid drug” made by another Tang-connected company, American Laboratories. While we haven’t been able to review a copy of the lawsuit (if any of our community members have access to PACER, please reach out at info@gdatf.org), American Laboratories is known to supply the active ingredient for Armour Thyroid. We’ll be reaching out to the FDA – again – to see if the departure of Mr. Tidmarsh affects the August 7th announcement regarding desiccated thyroid extract.
Note: While DTE falls under the Center for Biologics Evaluation and Research (CBER) instead of CDER, Dr. Tidmarsh served as acting director of CBER from July 30th through August 11th. The letters to manufacturers, distributors, and importers of DTE products went out on August 6th, and the official FDA announcement was made on August 7th.
The story on voclosporin was first reported by Adam Feuerstein at STAT news, but the article is behind a paywall. You can also read more about the latest developments in this piece from Matthew Perrone at AP.
10/21/25 – This new article from PharmaVoice (“Why a treatment older than the FDA is getting new regulatory scrutiny”) is worth a read for the commentary from Acella Pharmaceuticals CEO Art Deas, as well as a link to the updated Armour Thyroid FAQ on the AbbVie website. However, it doesn’t accurately reflect the timeline of threatened FDA enforcement action. The original FDA announcement was released on August 7th, meaning that the current countdown is at around 9.5 months. In addition, the framing as a “MAHA” issue fails to capture the broader history of this conflict, which includes decades of back-and-forth between the FDA, manufacturers of DTE products, endocrinologists, and the thyroid patient community.
10/8/25 – The American Thyroid Association sent a letter to U.S. FDA Commissioner Marty Makary offering up the expertise of ATA members to assist the FDA “in the development of mechanisms for safe regulation of desiccated thyroid extract from a scientific and medical standpoint.” The letter continues: “However, in the interim, we advocate to allow continued access to desiccated thyroid extract for patients.” You can read the letter in full on the ATA’s website.
9/18/25 – The American Thyroid Association released a statement via e-mail today, noting that the organization “supports regulations that ensure medication purity and consistency” but that “removal of the DTE from the marketplace during a potentially lengthy biologics license application would leave patients without access to DTE for an unknown period of time.” (EDIT: you can now read the full statement on the ATA’s website.)
9/9/25 – The American Association of Clinical Endocrinology has now weighed in: “While levothyroxine is recommended as the first-line therapy for most patients, AACE strongly supports equitable access and the principles of personalized medicine. DTE remains an alternative therapy that can be considered for select patients based on clinical judgment and individualized, evidence-based discussion between patients and their healthcare providers.” You can read the full statement here.
9/2/25 – If you are reading this, you are no doubt familiar with the FDA’s announcement last month regarding desiccated thyroid extract – and then the subsequent social media post from FDA Director Dr. Marty Makary promising that the FDA would “ensure access”. But you probably aren’t familiar with elamipretide, an investigational drug designed to treat Barth syndrome, an ultra-rare genetic disease. Last May, the FDA rejected the new drug application from Stealth Bio following 16 months of “priority” review. Three months later, Stealth Bio resubmitted the application – their third one. While this is obviously a different disease state, a different medication, and even a different drug approval process, this story illustrates that the process of securing FDA approval can sometimes be non-linear. This is why it’s important for the FDA to clarify whether the 8/13 social media post officially rescinds the 8/7 announcement and 8/6 letters to manufacturers, distributors, and importers. And if the original guidance isn’t rescinded, it’s critical for the FDA to clarify when the clock starts running on its “12-month” transition period.
8/26/25 – This statement from Acella Pharmaceuticals is on their product FAQ page:
8/19/25 – GDATF received the following statement via email in response to a prior inquiry to AbbVie:
8/19/25 – GDATF reached out to the FDA to ask whether the announcement and letters dated August 6th/7th had been rescinded (and if not, whether FDA could provide clarity on a timeline for potential enforcement action.) The following response was received today: We appreciate you sharing your views with the Agency. We recognize the significance of your concerns regarding the future availability of desiccated thyroid medications. FDA is committed to advancing the science to support making more treatments available to Americans, and we will continue to work with any company developing products for marketing approval. Your feedback about the importance of desiccated thyroid has been noted.
8/18/25 – This piece from Medscape includes some interesting insights from Dr. Antonio Bianco, MD, who has done a great deal of research on treatments for hypothyroidism. (Login might be required to view the article, but setting up an account with Medscape should be free.)
8/14/25 – This informative article from The Pink Sheet (a publication that covers regulatory and policy issues related to the pharmaceutical industry) was written by Manas Mishra and provides some additional background, including statements from AbbVie and Acella as well as information on a Citizen’s Petition filed by AbbVie in 2024. The article is behind a paywall, but you can sign up for a 7-day free trial.
8/13/25 – FDA Commissioner Dr. Marty Makary posted on X that “FDA is committed to pursuing the first-ever approval of desiccated thyroid extract, pending results of the ongoing clinical trials. In the mean time, we will ensure access for all Americans.” This is reassuring for patients, but raises new questions, as the process for getting a biologics license application approved is both lengthy and costly, and the letters sent on Aug. 6th mentioned a 12-month transition period. Hopefully, the FDA will provide some clarity in a future communication.
8/12/25 (update) – This July 2025 piece in “Regulatory Focus” sheds some light on the recent FDA announcement. This article reports on the newly appointed Director of the Center for Drug Evaluation and Research (CDER), who had previously made comments on LinkedIn about desiccated thyroid extract. A post from eight months ago noted, “The new FDA needs to remove harmful, useless drugs from the market. Let’s start with desiccated thyroid extract. An unapproved, crude pig tissue extract that is proven worse than synthetic thyroid hormone and harmful. Working with the new FDA to remove it permanently from the market.”
(Original Blog Post dated 8/12/25)
In an announcement dated August 7, 2025, the U.S. Food and Drug Administration (FDA) threatened future enforcement action against manufacturers, importers and distributors of desiccated thyroid extract (DTE) products such as Armour and NP Thyroid. The announcement states that following a transition period, “Manufacturers, importers and distributors of unapproved animal-derived thyroid medications may be subject to compliance action if they commercially distribute their unapproved products”. On August 6th, the FDA sent a separate letter to manufacturers, importers, and distributors with no specific date mentioned for the end of the transition period, but stating, “We believe it will require up to 12 months to safely transition patients to an FDA-approved thyroid hormone replacement product.”
Controversy over DTE products is not new. Back in 2013, I attended the American Thyroid Association’s Spring Symposium and Research Summit on “Treatment of Hypothyroidism: Exploring the Possibilities”. One of the presentations was from an FDA representative who discussed whether DTE products were “grandfathered” from the regular drug approval process. Although DTE products were used as the front-line treatment for hypothyroidism for decades prior to (and after) the passage of the Federal Food, Drug, and Cosmetic Act in 1938, the FDA has long maintained that DTE products are not “grandfathered”.
More recently, in 2020, the FDA sent separate letters to RLC Labs Inc. and Acella Pharmaceuticals following facility inspections at manufacturing sites for both companies, citing specific quality control issues and noting in both letters that DTE products fall under a newly updated regulatory definition of “biological products”, thus requiring a biologics license application (BLA) to engage in interstate commerce.
In September 2022, a branch chief from the FDA’s Office of Compounding Quality and Compliance sent a letter to the National Association of Boards of Pharmacy noting that the “biologic” designation would affect the eligibility of DTE products for compounding. Two months later, the FDA held a meeting with the Alliance for Pharmacy Compounding, and a new letter was issued from Frances G. Bormel (Director, Office of Compounding Quality and Compliance) with a softer tone: “We understand that many Americans take medication to treat hypothyroidism, and some choose to take DTE products to treat their medical condition…the agency recognizes our activities are of great interest to a wide range of stakeholders.” That letter went on to state that the FDA would focus any enforcement on issues that “pose the greatest public health risks, such as serious adverse events or serious product quality or adulteration issues”.
In the section “Information for Health Care Providers”, this latest announcement states, “FDA encourages health care providers to contact patients taking unapproved animal-derived thyroid medication to transition them to an FDA-approved medication to treat hypothyroidism.” More clarity is needed from the FDA as to whether the intention is to force manufacturers to go through the lengthy (and costly) BLA process or whether they are looking to remove the products entirely. There’s no mention of the transition period starting after a suitable time for approval of a BLA – which itself can take a full 12 months in the absence of expedited review. (There are multiple programs that provide faster review, but they are typically used for new medications that fill “unmet needs”.)
Perspective from Patients and Physicians
For patients who still feel unwell on T4 monotherapy (despite consistently taking their medication as directed and having other possible conditions ruled out), more endocrinologists seem open these days to a trial of combination therapy. As Dr. David Cooper explained in a 2024 webinar co-hosted by GDATF and the American Association of Endocrine Surgeons, “It used to be that people who did that like me were considered kind of crazy and outside the realm of medical practice. But now it’s being more accepted to do this.”
For patients wishing to try combination therapy, endocrinologists typically prefer to prescribe Cytomel (liothyronine sodium) plus levothyroxine instead of DTE. Concerns regarding DTE include an altered T4:T3 ratio compared to what is normally present in the human body (DTE contains significantly more T3) as well as potential impurities and inconsistency between batches. All of these concerns are mentioned in the FDA’s recent announcement.
However, a 2017 survey conducted by the American Thyroid Association of more than 12,000 patients found that those taking DTE products “were less likely to report problems with weight management, fatigue/energy levels, mood, and memory compared to those taking either the L-T4 monotherapy or the combination therapy.” It’s also important to note that many of these patients first tried all of the other available options (generic levothyroxine, brand-name levothyroxine, and levothyroxine with Cytomel) before landing on DTE. So when the FDA states that patients should be transitioned to “an FDA-approved medication to treat hypothyroidism”, this means forcing some patients back into an option that was previously tried – and that failed to provide symptom relief.
There is ongoing research to help answer the question of why some patients have a preference for combination therapy (it could be genetic) and why DTE products in particular score higher than other options on patient satisfaction. AbbVie is currently recruiting for a trial that compares Armour Thyroid to synthetic T4.
Adverse Events and Recalls
The FDA letter to manufacturers states that the FDA is aware of over 500 adverse event reports associated with DTE products “from 1968 through February 2025, with a substantial increase between 2019-2020 that may have been related to several voluntary recalls of subpotent or superpotent ADT products.” However, some complaints could be related to overtreatment or undertreatment, which can happen with other treatment options for hypothyroidism. And as Dr. Cooper noted about combination therapy in general for Graves’ patients, “Some people…feel worse because they develop hyperthyroid symptoms on it” and these patients end up back on T4 monotherapy.
Of course, human error can cause potentially dangerous and life-threatening consequences. For example, in one well-known case from 2011, a Massachusetts teen was given 1,000 times too much T3 by a compounding pharmacy, resulting in four emergency room visits and two hospitalizations for heart problems.
As for recalls, that can happen with non-DTE products as well. In 2023, IBSA initiated a voluntary recall of TIROSINT-SOL over potential potency issues. And there is a current recall from Accord Healthcare, Inc. for levothyroxine involving reduced potency observed during long-term stability testing.
And ProPublica recently reported that a laboratory in India with known violations of “Current Good Manufacturing Practice (CGMP)” had been granted an exception that allowed it to continue shipping levothyroxine and other drugs into the United States.
Moving Forward
Ensuring that patients have access to safe, effective medications – while avoiding potential drug shortages – is a delicate balancing act. If the FDA holds to the 12-month “transition” timeline in their latest announcement, this would be a seismic shift with broader ramifications for all patients who live with hypothyroidism. But I’m hopeful that the events of 2022 indicate that the FDA is willing to listen to stakeholder concerns and adjust course as needed.
I expect that we’ll get more clarity in the coming days and weeks – and potentially some compromise – as patients, manufacturers, pharmacists, and physicians weigh in. Stay tuned. (And bookmark this page for the latest developments).