Changes in Diagnostic Test Policies Help Reduce Risks for Patients

Countless Americans rely on in vitro diagnostics—tests that analyze blood, saliva, or other samples—to detect health risks and diseases. But decades-old regulatory loopholes have allowed some of these tests, known as lab-developed tests (LDTs), to escape federal review, often exposing patients to inaccurate and unproven products. These loopholes, for example, allowed the now-defunct Silicon Valley startup Theranos to market its faulty products to patients. And in another case, as a December 2022 ProPublica report showed, gaps in oversight have allowed unapproved prenatal tests to mislead pregnant patients about the health of their fetuses, at times resulting in irreversible harm.

How can this happen? Most clinical tests are required to undergo review by the U.S. Food and Drug Administration before they’re used on patients. However, LDTs can come to market without such oversight simply because they’re created and used in a single lab. This regulatory system made more sense when it was established in 1976, when LDTs were used under very limited circumstances, such as to diagnose rare diseases that could not be assessed with commercially available tests. But today, the tests have become widespread and increasingly complex, and are used for a variety of diseases, including cancer, exposing more people to potential harm from unreliable or misleading test results. Lawrence Gostin, a professor of law and bioethics at Georgetown University, described the situation to ProPublica as “a Wild West scenario where everybody is on their own.”

Pew advocates for policy changes that help patients

Since 2017, The Pew Charitable Trusts has worked to solve this problem, advocating for strong FDA regulations to ensure that tests return reliable results; producing research on the public health risks from inaccurate LDTs; and joining dozens of patient groups, manufacturers, laboratories, and medical organizations in callings for congressional action to improve clinical test oversight.

During the early months of the COVID-19 pandemic, FDA announced that every test marketed to screen for or diagnose coronavirus, including LDTs, must receive an emergency use authorization (EUA), a temporary and expedited approval process for urgently needed medical products. Subsequent research published in the New England Journal of Medicine illustrated the value of FDA’s oversight, finding that the agency detected flaws in more than 80 of 125 COVID-19 LDTs that it reviewed.

But these gains were threatened in August 2020 when the Department of Health and Human Services (HHS) prohibited FDA from reviewing COVID-19 tests under EUA, potentially allowing inaccurate tests to enter the market and undermining efforts to control the disease’s spread. In subsequent months, Pew worked to overturn the HHS decision, submitting a letter to HHS Secretary Xavier Becerra in April 2021 and publishing research on the variety of COVID-19 tests and FDA’s role in regulating them. In November 2021, HHS withdrew its decision, thus allowing FDA to again review COVID-19 tests for accuracy and, importantly, to step in before patients used problematic tests.

Pew research shines a spotlight on a shadowy market

Also in 2021, Pew published research examining the role of LDTs in the in vitro diagnostic test market, finding that the clinical lab industry’s lack of transparency puts patients in danger. Because LDTs are not required to be centrally registered or tracked, it is impossible to say precisely how many of them are on the market, when and why they are used, or how their performance compares with FDA-reviewed diagnostics. Indeed, even seasoned clinical lab managers—nearly 200 of whom were surveyed for the study—often don’t understand the difference between FDA-regulated in vitro diagnostic tests and LDTs. Furthermore, inaccurate results from LDTs can lead to unnecessary expense, trauma, or worse: A false positive can lead a patient to pursue unnecessary treatment; a false negative can lead a patient to forgo necessary treatment. But labs are not required to disclose when their products harm patients, so no data exists on the number and nature of incidents tied to inaccurate tests.

In January 2022, the Pew study’s findings informed a groundbreaking New York Times investigation into inaccurate prenatal tests, which found that blood tests that look for fetal genetic abnormalities can return false positive results 80% to 93% of the time. Three months later, FDA issued a safety communication to patients and health care providers about the risk of false results from noninvasive prenatal testing, stating that “[w]ithout proper understanding of how these tests should be used, people may make inappropriate health care decisions regarding their pregnancy.”

Diverse stakeholders unite in call for stronger oversight

Pew has consistently called on Congress to pass legislation to close the federal loopholes that allow LDTs to evade FDA review. In April 2022, Pew staff testified before the Senate Health, Education, Labor and Pensions Committee, which later approved the bipartisan Verifying Accurate Leading-Edge IVCT (in vitro clinical tests) Development Act—the VALID Act—a measure that would require all tests, including LDTs, to be held to the same FDA risk-based standards. Pew then led a group of nearly 50 organizations—including medical test manufacturers, laboratories, and groups representing physicians, health care providers, patients, and consumers—urging leaders of the House and Senate to pass the bill.

Ultimately, Congress did not pass the VALID Act in 2022, but lawmakers still have ample opportunity to close harmful gaps in the federal oversight of diagnostic tests. Doing so will help FDA better regulate the lab industry, hold test manufacturers accountable, and protect the tens of millions of Americans who rely on these products to make critical, potentially life-changing decisions about their health.

Kathy Talkington directs The Pew Charitable Trusts’ work on public health issues.