Quanterix's blood test for multiple sclerosis relapse risk nabs FDA breakthrough nod

Though relapsing-remitting multiple sclerosis, or RRMS, can be managed with many of the approved treatments for MS symptoms, there is still no scientifically proven, FDA-cleared way to predict when or if another relapse period will occur.

There may be one on the horizon, however, since Quanterix recently received the regulator’s breakthrough device designation for a blood test designed to do exactly that.

In RRMS, the most common form of multiple sclerosis, periods of stable remission are interrupted by relapses of new or worsening symptoms—like visual loss or double vision, numbness, weakness and balance issues—that last at least 48 hours. Quanterix’s test is designed to look for signs that a patient will relapse within the next four years.

The agency’s designation recognizes that the test represents a novel way to address a currently unmet need in healthcare and offers a somewhat clearer and potentially speedier path for Quanterix to bring the test through the FDA review process.

The blood test is based on the Massachusetts-based company’s Simoa immunoassay technology, which is able to measure proteins, nucleic acids and other biomarkers of disease at a single-molecule level, requiring only a regular blood sample. The Simoa platform is also used by Quanterix’s Alzheimer’s diagnostic, which homes in on the pTau-181 protein and snagged its own breakthrough designation last year.

The RRMS test, meanwhile, analyzes the serum and plasma in a blood sample to measure neurofilament light chain (NfL), a protein that’s been linked to axonal damage caused by neurological diseases like MS, Alzheimer’s disease, amyotrophic lateral sclerosis and more.

Those findings can then be used alongside other clinical, imaging and laboratory assessments to determine the risk level that an RRMS patient will relapse within four years, which Quanterix said could help better tailor treatments to each patient’s specific relapse and remission patterns.

“For the more than 2 million people suffering from MS worldwide, there’s an important need for more informed and effective treatment options,” said CEO Kevin Hrusovsky. He noted that scoring breakthrough device designation for the test checked off a “key objective” on Quanterix’s 2022 to-do list and sets up the company to accelerate its development and—FDA willing—commercial rollout.

A retrospective study published last month confirmed that when the test detected higher levels of NfL, it correlated to an increased risk of future disease activity. The researchers found that the test was particularly helpful in predicting relapses in patients who were currently symptom-free.

They also used the test results to compare patients’ NfL levels after being treated with a variety of MS therapies. Monoclonal antibodies were linked to the lowest levels of the protein, followed by oral therapies, with platform injectables taking a distant third place. Those findings, the researchers said, mean the test could also be helpful in determining which form of treatment will be most effective for a given patient and could be used in pharmaceutical research to track the effects of new therapeutic approaches.