This legislation, known as the "Enhancing Clinical Laboratory Innovation and Access Act of 2026," significantly amends the Public Health Services Act to redefine the regulatory landscape for Laboratory Developed Tests (LDTs) . It explicitly states that LDTs will be regulated under the Clinical Laboratory Improvement Amendments (CLIA) and not the Federal Food, Drug, and Cosmetic Act (FDCA), clarifying a long-standing jurisdictional debate. The bill provides comprehensive definitions for key terms such as analytical validity, clinical validity, clinical use, investigational use, and the specific criteria that define an LDT, emphasizing that LDTs are not considered medical devices under the FDCA. A core provision requires that, two years after enactment, all LDTs for clinical use must demonstrate a reasonable assurance of both analytical and clinical validity . Analytical validity involves establishing and verifying performance specifications, while clinical validity requires documented evidence from sources like peer-reviewed literature, clinical studies, or real-world data. Laboratories have the option to obtain a supplemental affirmation of validity from approved third parties, including the New York State Department of Health, the MolDX Program, or even the Food and Drug Administration itself, which will be deemed an approved third party for this purpose. The bill mandates the establishment of a centralized, transparent database for LDTs for clinical use within two years of enactment. Laboratories will be required to submit detailed information about each LDT, including its purpose, specimen types, performance specifications, and any supplemental affirmations. Furthermore, the legislation introduces new requirements for test error reporting , obligating laboratories to report instances of serious harm or imminent public health threats related to LDTs within specific timeframes. The Secretary is empowered to review the analytical and clinical validity of LDTs based on credible scientific concerns, with a process for laboratories to respond and resolve identified issues. LDTs offered for investigational use must meet analytical validity standards and be clearly labeled as such, indicating that clinical validity has not yet been established. The bill also makes conforming amendments to the FDCA, explicitly excluding LDTs from device regulation and clarifying that certain devices used with LDTs are exempt from specific FDCA requirements. For Medicare coverage, a supplemental affirmation for an LDT will be considered equivalent to FDA approval or clearance. The bill also allows companion diagnostics to be either FDA-regulated devices or LDTs with supplemental affirmation. The legislation includes a transition plan, with most provisions taking effect two years post-enactment, and requires the Secretary to promulgate regulations, establish the database, and address potential conflicts of interest among oversight organizations. Finally, the bill mandates updates to CLIA regulations to reflect advancements in laboratory science, such as molecular diagnostics and digital pathology, within 180 days of enactment. It also requires the Centers for Medicare and Medicaid Services (CMS) to provide public notice and comment for sub-regulatory changes, hold annual open forums with clinical laboratories, and review CLIA regulations at least every five years to ensure they remain current with scientific and technological progress.