New test aims to spot signs of Parkinson's disease within a teardrop

If the eyes are windows into the soul, Axim Biotechnologies believes that tears can provide a peek into the inner workings of the brain—and potentially carry with them the signs of Parkinson’s disease.

The company announced that it has developed a rapid, point-of-care assay that could be used for the neurodegenerative condition, by searching for abnormal formations of a key brain protein within a single teardrop.

Known as alpha-synuclein, the protein biomarker has been described as a possible driver of Parkinson’s, as it misfolds and causes clumps to form in the disease’s characteristic Lewy bodies that cluster within the brain. 

According to a separate study published earlier this year in The Lancet Neurology, researchers found that the presence of abnormal alpha-synuclein proteins within a person’s cerebrospinal fluid was highly accurate in predicting whether or not they had Parkinson’s disease when compared with healthy volunteers.

But now, Axim claims it can reach a diagnosis without requiring a painful spinal tap to collect a sample. The company said there can be enough alpha-synuclein in a person’s tear fluid to deliver a quantitative result in less than 10 minutes, without the use of complex lab hardware—though Axim did not provide data on the test’s accuracy.

“With this new assay, Axim has immediately become a stakeholder in the Parkinson’s disease community, and through this breakthrough, we are making possible new paradigms for better clinical care, including earlier screening and diagnosis, targeted treatments and faster, cheaper drug development,” CEO John Huemoeller said in the company’s release.

Axim previously billed itself as a cannabinoid drug developer and once maintained a pipeline of topical-, capsule- and chewing gum-based treatments for conditions that spanned irritable bowel syndrome, psoriasis, nausea and more. It has since transitioned into a diagnostic test maker, with assays aimed at dry eye disease, as well as for COVID-19 and cancer.

The San Diego-based company acquired Advanced Tear Diagnostics in late 2021, with a deal that covered two FDA-cleared tests for dry eye disease.

They included a lateral flow diagnostic for point-of-care use that measures the level of lactoferrin proteins in tear fluid, which work to protect the surface of the eye. The second test looks for ocular immunoglobulin E, an immune system biomarker linked to allergies. Axim said that low lactoferrin levels have also been linked to Parkinson’s disease and that the assay can be used alongside its alpha-synuclein test.

“Our proven expertise in developing tear-based diagnostic tests has led to the development of this test in record speed, and I’m extremely proud of our scientific team for their ability to expand our science to focus on such an important focus area as Parkinson’s,” Huemoeller said in the company’s announcement.