Decades of LDT Tension Leads to an Epic Three-Hour Oral Argument

The multi-decade battle over FDA’s power to regulate Laboratory Developed Tests (LDTs) had its day in court earlier this week.  On February 19, 2025, Judge Sean Jordan in the Eastern District of Texas heard oral arguments in American Clinical Laboratory Association (ACLA) and the Association for Molecular Pathology’s (AMP)[1] lawsuit against the Department of Health and Human Services.  ACLA and AMP are both challenging the legal validity of FDA’s Final LDT Rule that was issued last July.  The arguments lasted nearly three hours.  Judge Jordan began with asking the parties a foundational question: how do you define LDTs?  Without giving any indication of which way he was leaning, he asked multiple follow-up questions of both sides on topics ranging from the roles of analytical and clinical validity to the history of the FDCA and CLIA.  Citing the May 6 compliance date for Stage 1 of the LDT Rule, both ACLA and AMP asked that Judge Jordan issue his ruling expeditiously.  Judge Jordan said he would issue a decision as soon as possible.

Perhaps most notable in yesterday’s argument, though, was what didn’t happen.  Given the numerous changes in policy by the Trump administration, there had been much speculation that the government would now take a different position on this Biden-era rule.  It did not.  Department of Justice counsel strongly defended the rule throughout the hearing.  Interestingly, counsel focused his arguments exclusively on parrying legal attacks, rather than arguing why the rule was necessary to protect patients.  In contrast, AMP and ACLA both asserted that the rule would harm medical care. Perhaps anticipating a less than favorable outcome, DOJ counsel several times asked to be allowed to submit a brief on the question of the remedy in the event of an adverse ruling.

As our readers will recall, the LDT rule will bring, by FDA’s estimates, hundreds of thousands of laboratory tests under FDA’s regulatory purview.  Despite this impending massive change in regulatory scope, the President and his Department of Government Efficiency (DOGE) fired hundreds of FDA employees this past weekend.  Many of the fired employees were within the Center for Devices and Radiological Health—the Center that is tasked with regulating all devices, including in vitro diagnostics, which FDA argues includes LDTs.  These firings will stretch the Center’s resources to take on its existing workload, let alone handle thousands of complex and innovative LDTs.  We have previously raised concerns about the number of resources that will realistically be needed for CDRH to regulate LDTs (see our prior post here).

A major concern for laboratories, particularly those who have introduced new tests since the final rule was issued, will be availability of resources to review pre-submissions ahead of the Stage 4 and 5 implementation dates.  Notably, the last question Judge Jordan asked of ACLA was on this specific point.  Judge Jordan asked ACLA for confirmation that he understood correctly that pre-market submission was the major burden for labs and that while pre-market submission compliance dates are still several years away, labs should be preparing now to meet FDA’s pre-market expectations.  ACLA, of course, confirmed that was true.

Labs that will need to gain clearance/approval for their tests will need to begin the process soon to ensure they understand FDA’s expectations for analytical and clinical validity.  (That, of course, is not unique to labs with LDTs; kit manufacturers also need to obtain those insights well before they begin studies.)  The process for gaining this alignment is through the pre-submission program.  The last time CDRH was significantly resource constrained (i.e., during COVID), however, the Center stopped reviewing nearly all pre-submissions (see our prior post here).  A surge in pre-subs from labs combined with a shortage of qualified reviewers will almost certainly lead to significant delays in getting feedback, or, as happened during COVID, receiving no feedback at all.  If this happens, laboratories will not be able to anticipate what data FDA wants.

The first phase of the rule, which takes effect in less than three months, requires laboratories to have certain policies and procedures in place to begin handling complaints, reporting Medical Device Reports, and reporting corrections/removals.  While not terribly informative, under the prior administration, FDA held a webinar to outline the requirements of this Stage.  The materials from this webinar are still available on FDA’s website (here).

FDA had been scheduled to hold a webinar on the Stage 2 (May 2026) requirements related to the investigational device requirements for LDTs later this month.  Since the new administration took office, however, the webinar page has been taken down from FDA’s website.  This raises the question of whether and to what extent, if the rule moves forward, will FDA provide any tools to help laboratories as they seek to comply with these new requirements.

The LDT Rule itself provides no operational guidance, but only a definition.  The preamble to the Rule references planned or possible guidances more than 200 times, highlighting nearly a dozen areas for guidance development.  In fact, FDA has three guidances on its “A list” planned for this fiscal year that are specifically related to the LDT Rule or IVD (which FDA says includes LDTs) labeling (see here).  It’s unclear at this time whether any of these guidances will be issued, if the rule moves forward.

In addition, we understand that at this time FDA is unable to consult outside experts.  This restriction could significantly affect the Agency from learning from clinical and technical experts about the benefits and risks of certain tests as well as interpreting the clinical context of MDRs that it would start to receive if Stage 1 goes into effect.  As those that have worked with FDA know, the Agency is not an expert on all disease states or technologies.  This knowledge gap may be further exacerbated with MDRs for novel LDTs.  This inability to consult external experts could make communicating with FDA on important topics of safety and effectiveness even more challenging.

Taken together, should the rule go into effect, CDRH may be even less prepared for LDT regulation than it was a short time ago.  Thirty-three years after FDA first said it could regulate LDTs, we now wait to see if the court will allow the rule to stand.

[1] Hyman, Phelps & McNamara represents AMP in this litigation.