Test to Monitor Tysabri Levels in Relapsing MS Patients, moNATor by Abreos Biosciences, Available in US

Abreos Biosciences announced the U.S. launch of moNATor, a laboratory-developed test that can help physicians monitor the levels of Tysabri (natalizumab) in patients with multiple sclerosis (MS).

Tysabri (approved for relapsing forms of MS, by Biogen) administered at a dose of 300 mg every four weeks is known to be effective. But its use is also linked to a higher risk of progressive multifocal leukoencephalopathy (PML), a rare but potentially deadly viral infection of the brain  caused by the John Cunningham (JC) virus.

Recently, Biogen researchers used a U.S. risk evaluation and mitigation program for Tysabri users, called the TOUCH Prescribing Program, to determine whether a less frequent dosing regimen — called an extended interval dosing — might change a patient’s PML risk.

They found that extending the dosing periods of treatment, from the standard once every four weeks to one infusion given up to every 12 weeks, did help to significantly lower the risk of PML while maintaining treatment effectiveness.

The use of moNATor provides data on individual Tysabri concentration levels, which can help guide physicians in decision-making regarding ideal dosing intervals.

“Biologics are among the most powerful therapeutics available for many serious diseases, yet many patients are under or over-dosed due to the lack of simple monitoring tests that can tell how much drug a patient has in their blood. We are hoping to make personalized, precision dosing a reality for these patients,” Bradley Messmer, PhD, CEO and founder of Abreos, said in a press release.

Abreos’ first commercial product, moNATor uses its patent-protected Veritope technology platform. The platform allows physicians to monitor concentration levels of several antibody therapies, including biosimilars, so as to better optimize both the dose and its timing to achieve a more ideal and safe response.

The test was given to a select group of physicians prior to its launch, and has been successfully used in hundreds of patients, the company reports.

“The MS community is working to optimize drug safety in the therapeutics area, and I feel the recent data regarding Tysabri dosing interval extension and PML risk reduction is a major advance,” said John Foley, MD, founder of Rocky Mountain MS Clinic. “The moNATor assay provides another tool to the clinician which may help to optimize patient care through precision Tysabri dosing.”