Published on New York State Department of Health, Wadsworth Center (https://wadsworth.org)

Frequently Asked Questions about LDTs

Polarized light image of glucose. Richard Cole, Wadsworth Center

Frequently Asked Questions about LDTs

Information on the LDT review process can be found on CLEP’s Test Approval page[1] under the section entitled “Laboratory-developed tests”. This section includes details on the Tiered Evaluation of Laboratory Developed Tests Policy and the Risk Attestation Form. The Test Approval Page also includes information on LDTs used in clinical trials, LDTs not subject to evaluation, LDTs used in research testing, LDTs with at-home specimen collection, and information on exemptions from comprehensive submissions of LDTs. The CLEP home page[2] provides comprehensive information about the program and includes updates on the CLEP program. 

Yes. On November 8, 2023, CLEP posted released LDT Review Data that can be found here[3]. This includes information on how many LDTs have been submitted, how often an LDT requires more than one round of review, and how many LDTs have been received from labs that are in NYS vs. other states.

Yes. The review of an LDT is not a stand-alone service. The review of LDTs is part of the permitting process and is performed only for laboratories that have applied for or currently have a NYS clinical laboratory permit. Information on obtaining a permit can be found on CLEP’s Apply for a Permit page[4].

There is no fee specific to the review of an LDT. The costs are currently incorporated into permit and reference system fees paid by permitted laboratories. Fees are determined in accordance with NYS Public Health Law Section 576 and Subpart 58-3 of Title 10 of the New York Codes, Rules and Regulations. Additional information on fees can be found on CLEP’s Laboratory Fees page here[5].

Currently, the formula for the calculation of permit and reference system fees paid is established in the law (Public Health Law Section 576 and Subpart 58-3 of Title 10 of the New York Codes, Rules and Regulations). The process for obtaining a permit and LDT approval is the same for laboratories located inside and outside NYS. 

It is CLEP’s understanding that tests reviewed and approved by CLEP generally are subject to enforcement discretion, but ONLY with regard to FDA pre-market review requirements. FDA may determine that a test requires FDA clearance/approval in lieu of, or in addition to, CLEP LDT review and approval. Questions about interpretation of FDA requirements should be directed to the FDA. If you have questions about the final rule, you may contact FDA at LDTFinalRule@fda.hhs.gov[6]

In general, CLEP evaluates the analytical and clinical validity of an LDT, and certain additional parameters. CLEP has developed checklists for various categories of tests that describe information that needs to be submitted for an LDT review. The checklist can be found on CLEP’s Test Approval Page[7] under the section entitled “Making a Submission”. 

Yes. A laboratory may seek FDA review of any LDT. An FDA approved/cleared test, including an LDT, does not require CLEP review and approval. Modifications of an FDA approved/cleared test may require CLEP (or FDA) review. 

If a laboratory intends to use their LDT to test specimens originating in NYS, the laboratory must meet all CLEP permitting requirements, which includes having their LDT reviewed and approved. The LDT review requirement can be satisfied through the CLEP LDT review process or through FDA approval/clearance. FDA may determine that a test requires FDA clearance/approval in lieu of, or in addition to, CLEP LDT review and approval.

A laboratory may use an LDT approved by the FDA to perform testing on specimens originating from NYS only after they have met all CLEP permitting requirements. The laboratory must apply for and obtain a NYS clinical laboratory permit before testing any specimens originating from NYS. Information on obtaining a NYS clinical laboratory permit can be found here[8]

A permit is only required if the laboratory will use the FDA approved LDT to perform testing of specimens originating from NYS. Information on obtaining a NYS clinical laboratory permit can be found here[9].  

A POL located in NYS that has a CLIA Certificate of Compliance issued through POLEP or Certificate of Accreditation is not eligible for CLEP LDT review. Such a laboratory may voluntarily apply for a CLEP permit, making it eligible for CLEP LDT review. Please be aware that the requirements for obtaining a CLEP permit are significantly different from the requirements of obtaining a CLIA Certificate of Compliance or Certificate of Accreditation and additional requirements will need to be met, including, but not limited to, the requirement that testing personnel in a CLEP permitted laboratory be licensed by the NYS Education Department.

CLEP currently requires that all LDTs, including certain LDTs that currently are under FDA enforcement discretion, obtain NYS approval or FDA clearance/approval. These tests include those performed under the permit categories of Forensic Toxicology, Forensic Identity, and Parentage/Identity. 

Modifications to a CLEP approved LDT that change the intended use of the test and/or the testing procedure generally require review and approval. Additional information can be found on CLEP’s Test Approval page[10] under the section entitled “Modifications to Approved Assays”. 

If a laboratory intends to use their LDT to test specimens originating in NYS, the laboratory must meet all CLEP permitting requirements, which includes having their LDT reviewed and approved. The LDT review requirement can be satisfied through the CLEP LDT review process or through FDA approval/clearance. Information on obtaining a NYS clinical laboratory permit can be found here[11]. LDTs intended for “wellness” testing of specimens originating in NYS must be submitted. However, CLEP may determine, based upon a submitted LDT package, that certain tests do not require evaluation of analytical and clinical validity. Additional information can be found on CLEP’s Test Approval page[12] under the section entitled “Tests Not Subject to Evaluation”.

Questions about registration, reporting, labeling, QS requirements, and any other requirements in the final rule need to be directed to the FDA. If you have questions about the final rule, contact LDTFinalRule@fda.hhs.gov[13]

CLEP has developed checklists for various categories of tests that describe information that needs to be submitted for an LDT review. Using the checklist will facilitate the review of your LDT. The checklist can be found on CLEP’s Test Approval Page[14] under the section entitled “Making a Submission”. Laboratories should also consider applying for an exemption for a specific methodology and specimen type(s) once you have received full approval of a representative sampling of similar LDTs. Additional information can be found on CLEP’s Test Approval page[15] under the sections entitled “Making a Submission” and “Adding LDTs Under an Approved Exemption”.

Per CLEP’s Tiered Evaluation of Laboratory Developed Tests Policy[16], the laboratory must wait for written confirmation from CLEP that the LDT is approved under the exemption. 

The FDA final rule does not place any requirements on CLEP. However, the program anticipates increased volume of LDT submissions and is considering changes to respond to this increase.

At this time, CLEP does not anticipate pursuing re-accreditation as an FDA third party reviewer as a part of the FDA’s 510(k) Third Party Review Program[17].

When reviewing LDTs that include software, CLEP reviews the software, but only in the context of that specific LDT. CLEP does not review software or software functions in isolation and does not approve software for use in other LDTs or future LDTs.

CLEP review includes requirements for LDTs that incorporate algorithms or models derived by AI/ML.