Laboratory Developed Tests
Keeping you up-to-date on the latest regulatory developments affecting laboratory developed tests (LDTs).
Our dedicated LDT page provides foundational materials, legislative and regulatory history, and updates and analyses regarding initiatives to increase oversight over LDTs, including FDA’s LDT Final Rule (May 2024). On March 31, 2025, the District Court for the Eastern District of Texas concluded that the final rule exceeds FDA’s statutory authority and accordingly set aside and vacated the rule.
Our Life Sciences Regulatory & Compliance team will continue to keep this page updated with the latest happenings.
Updates & Analysis
| In Vitro Diagnostics (IVDs) | Laboratory Developed Tests (LDTs) | |
| Definition | Reagents, instruments, and systems intended for use in the diagnosis of disease or other conditions, including a determination of the state of health, in order to cure, mitigate, treat, or prevent disease or its sequelae that are used in the collection, preparation, and examination of specimens taken from the human body. | Tests that are intended for clinical use and that are designed, manufactured, and used within a high-complexity laboratory certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA). |
| Regulatory Status | Actively regulated by FDA as “devices” under the framework first established under the Medical Device Amendments of 1976 (MDA), which amended the Federal Food, Drug and Cosmetic Act to create a comprehensive system for the regulation of devices intended for human use. | FDA has held (and has maintained its stance over the years) that LDTs are medical devices, but following enactment of the MDA, generally practiced discretion over enforcement of LDTs. |
Following a decade of discourse with interested stakeholders, FDA published its proposed rule on October 3, 2023 that if finalized as proposed, would soon after subject the vast majority of LDTs to same regulatory requirements as in vitro diagnostics currently under the active oversight of the FDA, including for many LDTs, marketing authorization. Given in particular the significant growth in LDTs over the last decade, FDA’s proposal to subject LDT makers to more stringent oversight will be of significant interest to the laboratory testing industry.
Please see below for our analyses of the proposed rule:
Several legislative approaches for LDT regulation have been considered in recent years. The VALID Act is a longstanding legislative initiative that has been proposed in Congress several times over the last few years and would create an alternative regulatory regime for so-called “in vitro clinical tests” (IVCTs). IVCTs encompass both LDTs and IVDs, and as such would have a significant impact on the diagnostic industry at large.
- VALID Act (2023)
- VALID Act (2022)
- VALID Act (2021)
- VITAL Act (2021)
- VITAL Act (2020)
- VALID Act (2020)
- DAIA Discussion Draft (March 2017)
FDA has regularly commented and issued information for the laboratory testing industry. We have assembled a related list of key resources.
- Subcommittee on Health to Hold Hearing on Regulation of Diagnostic Tests and FDA's LDT Proposed Rule (March 2024)
- FDA Final Rule, Medical Devices; Quality System Regulation Amendments (February 2024)
- FDA Press Release, CDRH Announces Intent to Initiate the Reclassification Process for Most High Risk IVDs (January 2024)
- FDA and CMS Joint Statement on Laboratory Developed Tests (January 2024)
- FDA Webinar, Proposed Rule on Laboratory Developed Tests (October 2023)
- FDA Proposed Rule, Medical Devices; Laboratory Developed Tests (October 2023)
- FDA Preliminary Regulatory Impact Analysis for Laboratory Developed Tests Proposed Rule (September 2023)
- FDA Memorandum, Summary of 2020 Assessment of the First 125 EUA Requests from Laboratories for Molecular Diagnostic Tests for SARS-CoV-2 (September 2023)
- FDA Press Release, FDA Proposes Rule Aimed at Helping to Ensure Safety and Effectiveness of Laboratory Developed Tests (September 2023)
- FDA Final Guidance, Oncology Drug Products Used with Certain In Vitro Diagnostic Tests: Pilot Program (June 2023)
- FDA Press Release, FDA Launches Pilot Program to Help Reduce Risks Associated with Using Laboratory Developed Tests to Identify Cancer Biomarkers (June 2023)
- FDA Webpage, Oncology Drug Products Used with Certain In Vitro Diagnostics Pilots Program (June 2023)
- FDA Final Guidance, Policy for Coronavirus Disease-2019 Tests (Revised, Seventh Edition) (January 2023)
- FDA Safety Communication, Genetic Non-Invasive Prenatal Screening Tests May Have False Results (April 2022)
- FDA Press Release, FDA Announces Collaborative Review of Scientific Evidence to Support Associations Between Genetic Information and Specific Medications (February 2020)
- FDA Webpage, Direct-to-Consumer Tests (Last Updated, December 2019)
- FDA Safety Communication, The FDA Warns Against the Use of Many Genetic Tests with Unapproved Claims to Predict Patient Response to Specific Medications (October 2018)
- FDA, Discussion Paper on Laboratory Tests (LDTs) (January 2017)
- FDA, The Public Health Evidence for FDA Oversight of Laboratory Developed Tests: 20 Case Studies (November 2015)
- FDA Draft Guidance, FDA Notification and Medical Device Reporting for Laboratory Developed Tests (LDTs) (October 2014)
- FDA Draft Guidance, Framework for Regulatory Oversight of Laboratory Developed Tests (LDTs) (October 2014)
- FDA Notification to Congress regarding Intent to Issue Draft Guidance on Oversight of LDTs (July 2014)
- FDA Public Workshop, Oversight of Laboratory Developed Tests; Public Meeting; Request for Comments (June 2010)
- FDA Issues Final Rule on Regulation of Laboratory Developed Tests
- FDA’s Laboratory Developed Test (LDT) Final Rule Under OIRA Review; Subcommittee on Health to Hold Hearing on Regulation of Diagnostic Test
- FDA Targets April 2024 for Laboratory Developed Test (LDT) Final Rule
- Mark Your Calendars: This Halloween, Don’t Miss FDA’s LDT Webinar
- FDA Proposes Phased Approach to Regulating Laboratory Developed Tests
- LDT Proposed Rule Remains Under OIRA Review
- PM360: Marketing Laboratory Developed Tests
Lead Editor
- Steven Tjoe
Steven Tjoe
Partner
Contributing Editors
- Matt Wetzel
Matt Wetzel
PartnerLife Sciences Regulatory & Compliance