FDA Can’t Reclassify Its Way Out of Reviewing 100,000 LDT Submissions

On January 31, 2024, FDA announced its intent to initiate the reclassification process for most in vitro diagnostic (IVD) products that are currently class III (high risk) into class II (moderate risk). Most of these reclassified tests will supposedly be infectious disease and companion diagnostic IVDs. Reclassification would allow developers to seek clearance for substantially equivalent tests through the 510(k) pathway rather than the more costly and time-consuming premarket approval (PMA) pathway.

The announcement also states that FDA expects most future companion diagnostic and infectious disease IVDs would be regulated as class II devices, even if they are novel and require de novo classification.

One can’t help but read this announcement as an effort by FDA to prepare for (or at least give the appearance of preparing for) the deluge of IVD premarket submissions the agency expects it will receive following (the presumed) finalization of its proposed rule regulating LDTs. As we outlined in a previous blog, by FDA’s own (artificially low) estimate, the agency anticipates in will receive, in a single year:

• 32,160 510(k) premarket notifications;
• 4,210 PMAs, PDPs, Panel-Track PMA Supplements; and
• 4,020 de novo

This is 10 times the number of submissions the agency currently receives in a year across all device types. These numbers look even worse when you consider that most of these LDTs would be high risk or novel and, therefore, result in 57 times more PMAs and 61 times more de novo submissions than the FDA normally receives in a year.

This is to say nothing of the expected doubling of annual device submissions FDA expects it will then receive on an ongoing basis. And as we note in that earlier blog, there is good reason to believe all of the above numbers are gross underestimates.

Perhaps this is why FDA is trying to preemptively reclassify most of the high-risk tests currently on the market and signaling that it expects most future companion diagnostic and infectious disease IVDs would be regulated as class II devices going forward. But there are reasons why this move will not lessen FDA’s workload nearly as much as it might seem at first blush.

First, all this would do is move the premarket submission from one bucket to another. LDTs that can demonstrate substantial equivalence to a reclassified predicate device will still have to submit a 510(k) premarket notification. More novel LDTs will need to pursue de novo classification, which in many cases requires extensive clinical data to support authorization. Either way, FDA will need to review each of these applications and within shorter MDUFA timelines to boot.

Second, the lower cost to developers to assemble, and user fee to file for, a 510(k) or de novo submission compared to a PMA could increase the overall number of applications FDA receives, as developers that might have been deterred by the high cost of a PMA decide that a 510(k) or de novo submission is more manageable.

Finally, the vast majority of these submissions, whether for 510(k) clearance, de novo classification or PMA are likely to be accompanied by pre-submission requests to ensure the data the laboratories will be presenting to FDA in their submission is what the agency will expect.

FDA simply does not have the resources to handle the apocalyptic volume of premarket submissions it will have to review if it finalizes the LDT rule. We have yet to see the agency put forth a plan that would meaningfully change this calculation (see e.g., our view of FDA’s farcical reference to its third-party review program). This reclassification announcement is no different.

While we commend FDA for taking a critical look at the regulatory burdens placed on current high-risk tests, it is no substitute for creating a meaningful plan for how it will address the resources needed should the agency finalize the proposed LDT rule.  We hope that the next announcement for FDA includes such a plan.