The U.S. Food and Drug Administration (FDA) announced marketing approval for the first diagnostic test for amyloid plaque, a key marker used to detect Alzheimer’s disease. The Lumipulse G β-Amyloid Ratio (1-42/1-40) test will be used on older adults to help confirm the presence of the progressive disease that’s also referred to as senile dementia.

According to the National Institutes of Health, over six million Americans may be suffering from dementia. While there are no known cures for Alzheimer’s, early and accurate diagnosis of the condition can help healthcare professionals and the patient’s support network plan treatment options to slow the disease’s progression.

The Lumipulse test, manufactured by the Japanese biotechnology company, Fujirebio, is designed to provide early confirmation of an Alzheimer’s diagnosis when used in conjunction with other diagnostic procedures. The test is intended to be administered to adults who are 55 and older and are presenting with cognitive impairment.

The Lumipulse test works by measuring the ratio of β-amyloid 1-42 and β-amyloid 1-40, two specific proteins that can form plaques which are a key sign of Alzheimer’s. Lumipulse tests the ratios of these proteins in the cerebral spinal fluid (CSF) of a patient. This CSF ratio can help healthcare professionals determine whether a patient is likely to have amyloid plaques in their brain as well. 

Up until now, doctors seeking to confirm the presence of amyloid plaque in the brain would have to use a positron emission tomography (PET) scan. PET scans are a costly and slow option that detects and visualizes amyloid plaques in a patient’s brain. Nonetheless, PET scans can detect conditions that will lead to Alzheimer’s disease years before clinical symptoms manifest.

Positive and negative Lumipulse test results have been shown to be consistent with the presence or absence of amyloid plaques at a similar rate to a PET scan. Dr. Jeff Shuren, M.D., J.D., director of the FDA’s Center for Devices and Radiological Health, underscored the significance of the Lumipulse test saying, “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.”

As Dr. Shuren points out, the ability to get “same day” results “without the radiation risk” could make Alzheimer diagnosis cheaper and safer than ever before. Even if the test returns a negative result, the preliminary exclusion of Alzheimer’s as a likely diagnosis allows doctors to pursue other likely causes of the patient’s cognitive difficulties.

While the Limupulse is not able to single-handedly diagnose Alzheimer’s disease, its approval offers doctors the option to reduce the time spent and risk faced by patients looking for answers.