Specific Test Categories or Technologies: Laboratory Developed Tests FAQs
A: TDM tests, including mass spectrometry-based TDMs, are IVDs. TDM tests manufactured by laboratories are covered by the final rule and the phaseout policy described in the preamble to the final rule.
A: Newborn screening tests, including those offered as LDTs, are IVDs and generally fall within the scope of the phaseout policy. Certain newborn screening tests may fall within one of the targeted enforcement discretion policies in the preamble, such as the policy for "currently marketed IVDs offered as LDTs" (i.e., those that were first marketed prior to May 6, 2024) or the policy for LDTs approved by, conditionally approved by, or within an approved exemption from full technical documentation, under NYS CLEP.
A: Generally, laboratory developed tests (LDTs) for an emerging outbreak for which there is no relevant 564 declaration, such as Highly Pathogenic Avian Influenza (HPAI) or oropouche, offered by clinical laboratories that are certified under CLIA and qualified to perform high-complexity testing currently fall under the FDA’s general enforcement discretion approach for LDTs. At this time, the FDA generally does not expect clinical laboratories that are certified under CLIA and qualified to perform high-complexity testing to request marketing authorization from the FDA for their LDTs for HPAI or oropouche prior to them offering those LDTs. FDA also would not issue EUAs for such IVDs given that there is no relevant section 564 declaration.
FDA expects compliance with applicable device requirements for IVDs for emerging outbreaks for which there is no relevant 564 declaration as described in the staged phaseout policy and targeted enforcement discretion policies in the preamble to the LDT final rule. The first stage of the phaseout policy begins May 6, 2025.
A: For companion diagnostics currently classified as Class III with planned PMA submissions, companies should generally continue with their PMA submission plans unless the classification of the device is changed. If the companion diagnostic has a new intended use, it may be eligible for a de novo classification if the companion diagnostic meets the criteria for classification into Class II. In such cases, companies may submit a de novo classification request to potentially classify the device as Class II if it presents low to moderate risk and there is no legally marketed predicate device.
The original classification of a device, including class III companion diagnostic devices, can be changed through reclassification, for which multiple processes exist in the FD&C Act and FDA's regulations. These processes may include issuing a proposed order(s), convening a classification panel as appropriate, receiving and considering public comment, and issuing a final order(s).
On January 31, 2024, FDA announced its intent to initiate the reclassification process for most IVDs that are currently class III into class II. FDA aims to complete this reclassification process by November 2027, which would allow manufacturers of certain types of IVDs to seek marketing clearance through the 510(k) pathway. This reclassification initiative includes the majority of infectious disease and companion diagnostic IVDs, such as nucleic acid-based, in situ hybridization, and immunohistochemistry-based companion diagnostics used to select cancer treatments.
FDA intends to continue taking a risk-based approach in the classification of IVDs to determine the appropriate level of regulatory controls and to assess whether a new IVD may be classified into class I or class II through De Novo classification (and special controls established), rather than being class III and subject to the PMA pathway. Based on our experience, we believe that special controls could be developed, along with general controls, that could provide a reasonable assurance of safety and effectiveness for most future companion diagnostics and infectious disease IVDs.
A predicate device for purposes of FDA clearance of a 510(k) submission is a "legally marketed device." A legally marketed device appropriate to serve as a predicate is a device that was legally marketed prior to May 28, 1976 or a device which has been reclassified from class III to class II or Class I (the predicate), or a device which has been found to be substantially equivalent through the 510(k) premarket notification process. Once a device has been reclassified from Class III to Class II, it may then potentially serve as a predicate device for future 510(k) submissions for other devices of the same device type, streamlining the regulatory pathway for subsequent devices.