FDA approves first in vitro test for early detection of Alzheimer’s diseaseMay 6, 2022
The US Food and Drug Administration has granted marketing approval for the first in vitro diagnostic test for early detection of amyloid plaques associated with Alzheimer’s disease. The Lumipulse G β-Amyloid Ratio (1-42/1-40) test is intended to be used in adult patients, aged 55 years and older, presenting with cognitive impairment who are being evaluated for Alzheimer’s Disease and other causes of cognitive decline. The new test can potentially replace the expensive and cumbersome PET scan (positron emission tomography) investigation, which was the only option available to detect the disease.
The Lumipulse G β-amyloid Ratio (1-42/1-40), which is developed and to be marketed by Fujirebio Diagnostics Inc., 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. There was an unmet need for a reliable and safe test that can accurately identify patients with amyloid plaques consistent with Alzheimer’s disease. While amyloid plaques can occur in other diseases, being able to detect the presence of plaque, along with other evaluations, helps the doctor determine the probable cause of the patient’s symptoms and findings.
“The availability of an in vitro diagnostic test that can potentially eliminate the need for time-consuming and expensive PET scans is great news for individuals and families concerned with the possibility of an Alzheimer’s disease diagnosis,” says Jeff Shuren, M.D., J.D., director of the FDA’s Center for Devices and Radiological Health.
“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,” Dr Shuren added in an FDA statement on Thursday.
Clinical symptoms of Alzheimer’s disease, a brain disorder known to slowly destroy memory and thinking skills, and, eventually, the ability to carry out the simplest tasks, first appears typically later in life in most people. A progressive disease, it gets worse over time. Early and accurate diagnosis is important to help patients and caregivers with planning and early treatment options.
Prior to the newly authorised test, doctors used positron emission tomography (PET) scans, a potentially costly and cumbersome option, to detect/visualise amyloid plaques in a patient’s brain, often years before clinical symptom onset, to aid in diagnosing Alzheimer’s disease.
The Lumipulse test is intended to measure the ratio of β-amyloid 1-42 and β-amyloid 1-40 (specific proteins that can accumulate and form plaques) concentrations found in human cerebral spinal fluid (CSF), which can help physicians determine whether a patient is likely to have amyloid plaques, a hallmark sign of Alzheimer’s disease. Results must be interpreted in conjunction with other patient clinical information.
A positive Lumipulse G β-amyloid Ratio (1-42/1-40) test result is consistent with the presence of amyloid plaques, similar to what would be seen in a PET scan. A negative result is consistent with a negative amyloid PET scan result. A negative test result reduces the likelihood that a patient’s cognitive impairment is due to Alzheimer’s disease, enabling physicians to pursue other causes of cognitive decline and dementia. The test is not intended as a screening or stand-alone diagnostic assay. There is also the possibility that a positive test result could be seen in patients with other types of neurologic conditions, as well as in older cognitively healthy people, which underscores the importance of using this test in conjunction with other clinical evaluations.
The FDA evaluated the safety and effectiveness of this 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, Alzheimer’s disease. This could lead to psychological distress, delay in receiving a correct diagnosis as well as expense and the risk for side effects from unnecessary treatment. False negative test results could result in additional unnecessary diagnostic tests and potential delay in effective treatment. Importantly, the Lumipulse G β-amyloid Ratio (1-42/1-40) is not a stand-alone test and other clinical evaluations or additional tests should be used for determining treatment options.
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. 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.