Quest Diagnostics to Offer FDA-Cleared Alzheimer's Blood Test, Expanding Diagnostic Options

Quest Diagnostics has announced plans to offer laboratory testing based on Fujirebio Diagnostics' recently FDA-authorized Alzheimer's disease blood test. This move signifies a significant advancement in the accessibility and scalability of Alzheimer's diagnostics, potentially revolutionizing the approach to early detection and management of the disease.

Fujirebio's Groundbreaking Diagnostic

In May, Fujirebio's in vitro diagnostic became the first blood test to aid in the diagnosis of Alzheimer's cleared by the FDA. The Lumipulse G pTau 217/β-Amyloid 1-42 Plasma Ratio test compares the ratio of two proteins, pTau217 and beta-amyloid 1-42, to help identify patients with amyloid pathology associated with Alzheimer's. Fujirebio validated the test in a study of 499 people, demonstrating impressive positive and negative predictive values of 92% and 97%, respectively, with less than 20% of people receiving indeterminate results.

Quest's Strategic Move and Market Implications

Quest Diagnostics plans to make Fujirebio's test available for use by physicians and researchers this summer. This offering will expand Quest's portfolio beyond its existing laboratory-developed tests (LDTs), including a beta-amyloid 42/40 and pTau217 LDT launched in April.

Quest CEO Jim Davis highlighted the potential impact of this technology at a recent William Blair event, stating that "it over time will largely replace PET-CT as the primary diagnostic tool for the detection of Alzheimer's." Davis emphasized that testing for a combination of beta-amyloid and tau biomarkers could "give clinicians an earlier view of early onset Alzheimer's long before you would see it in a PET-CT."

Implications for Patient Care and Healthcare Systems

The introduction of blood-based Alzheimer's diagnostics represents a significant shift in patient care pathways. These tests could prove more accessible and scalable than current cerebrospinal fluid (CSF) tests, which require samples collected via lumbar puncture.

Davis underscored the potential benefits for primary care physicians, noting that "Primary care physicians are using this test to determine should a patient get referred to a neurologist or not. And the number one problem with Alzheimer's disease today is getting a referral into a neurologist." He added, "If a primary care physician can run a test to determine who really needs to get referred and who doesn't, it will be a huge help to the overall health system."

As companies develop medicines most effective in the early stages of Alzheimer's, the value of early and accurate diagnosis becomes increasingly critical. The integration of these blood tests into clinical practice could streamline the diagnostic process, potentially leading to earlier interventions and improved patient outcomes.