The Lumipulse G β-Amyloid Ratio 1-42/1-40 (Fujirebio Diagnostics) test detects amyloid plaques associated with AD in adults age 55 or older who are under investigation for AD and other causes of cognitive decline.
“The availability of an in vitro diagnostic test that can potentially eliminate the need for time-consuming and expensive [positron emission tomography (PET)] scans is great news for individuals and families concerned with the possibility of an Alzheimer’s disease diagnosis,” Jeff Shuren, MD, JD, director of the FDA’s Center for Devices and Radiological Health, said in a statement.
“With the Lumipulse test, there is a new option that can typically be completed the same day and can give doctors the same information regarding brain amyloid status, without the radiation risk, to help determine if a patient’s cognitive impairment is due to Alzheimer’s disease,” he added.
In its statement, the FDA notes that there is an “unmet need for a reliable and safe test that can accurately identify patients with amyloid plaques consistent with Alzheimer’s disease.”
The agency goes on to state that this new test may eliminate the need to use PET brain scans, a “potentially costly and cumbersome option” to visualize amyloid plaques for the diagnosis of AD.
The Lumipulse test measures the ratio of β-amyloid 1-42 and β-amyloid 1-40 concentrations in human cerebral spinal fluid (CSF). A positive Lumipulse G β-amyloid Ratio (1-42/1-40) test result is consistent with the presence of amyloid plaques, similar to that revealed in a PET scan. A negative result is consistent with a negative amyloid PET scan result.
However, the FDA notes that the test is not a stand-alone assay and should be used in conjunction with other clinical evaluations and additional tests to determine treatment options.
The FDA reports that it evaluated the safety and efficacy of the test in a clinical study of 292 CSF samples from the Alzheimer’s Disease Neuroimaging Initiative sample bank.
The samples were tested by the Lumipulse G β-amyloid Ratio (1-42/1-40) and compared with amyloid PET scan results. In this clinical study, 97% of individuals with Lumipulse G β-amyloid Ratio (1-42/1-40) positive results had the presence of amyloid plaques by PET scan and 84% of individuals with negative results had a negative amyloid PET scan.
The risks associated with the Lumipulse G β-amyloid Ratio (1-42/1-40) test are mainly the possibility of false-positive and false-negative test results.
False-positive results, in conjunction with other clinical information, could lead to an inappropriate diagnosis of, and unnecessary treatment for AD.
False-negative test results could result in additional unnecessary diagnostic tests and potential delay in effective treatment for AD.
The FDA reviewed the device through the De Novo premarket review pathway, a regulatory pathway for low- to moderate-risk devices of a new type.
The agency says this action “creates a new regulatory classification, which means that subsequent devices of the same type with the same intended use may go through FDA’s 510(k) premarket process, whereby devices can obtain marketing authorization by demonstrating substantial equivalence to a predicate device.”
The Lumipulse G β-amyloid Ratio (1-42/1-40) was granted Breakthrough Device designation, a process designed to expedite the development and review of devices that may provide for more effective treatment or diagnosis of life-threatening or irreversibly debilitating diseases or conditions.
A version of this article first appeared on Medscape.com.