The U.S. Food and Drug Administration (FDA) defines a Laboratory Developed Test (LDT) as “a type of in vitro diagnostic test that is designed, manufactured and used within a single laboratory”.
While some LDTs are relatively simple tests that measure single analytes, others are complex and measure or detect numerous analytes. Examples of LDTs include microscopic examinations such as Pap smears and manual cell counts, erythrocyte sedimentation rates (ESR), and microbiology cultures. Genomics and personalized medicine have greatly expanded the scope of LDTs and many are genetic tests developed for rare diseases. The potential impact of LDTs on patient care is expected to increase dramatically in the coming years.
Regulation of LDTs has been a source of controversy among the FDA, Congress, and industry stakeholders. The debate started in July 2014 after the FDA proposed guidance on a new LDT regulatory framework on the grounds that these tests had become much more complex and are used much more frequently and in higher-risk settings than before. Dr. Jeffrey E. Shuren, the director of the FDA unit that regulates medical devices pointed out that “there are examples of faulty lab-developed tests that have put patients in harm’s way.”
The FDA obtained feedback from all stakeholders on its proposal to regulate LDTs so that it could be refined in the best interest of public health. While some stakeholders judge that the decision to regulate LDTs would boost innovation and benefit consumers, others argue against it. Medical experts have voiced concerns about the proposed regulation. An article published in JAMA reveals that professors at the American College of Medical Genetics argue that the FDA’s proposed framework for regulating LDTs would have the following detrimental effects:
- Slow down the engine of innovation
- Potentially limit patient choice, and
- Threaten the future of genomic medicine
Similarly the American Hospital Association, the American Clinical Laboratory Association, and the American Medical Association argue that FDA regulation is unnecessary as under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), laboratories are already required to perform full analytical validation for all clinical testing (both FDA-approved and non-FDA approved tests, including LDTs). The Infectious Diseases Society of America (IDSA) is concerned that LDT oversight, as currently proposed by the FDA, could hinder patient access to existing high quality tests and threaten needed innovation of tests for constantly changing and emerging infectious diseases.
On the other hand, the American Society for Clinical Oncology (ASCO) has expressed its support for the agency’s draft guidance and recommends that the FDA should proceed with regulatory authority in a way that helps ensure ongoing innovation in the field of molecular testing, as well as timely patient access to validated molecular diagnostics that help improve use of precision medicine.
Clinical laboratories need to keep track of the debate on the regulation of LDTs. Regardless of how and when a consensus will be reached, laboratories should focus on maintaining the highest standards of compliance while providing accurate and timely testing to help healthcare providers enhance the quality of care.