Gold nanocrystals linked to neuronal repair, remyelination in multiple sclerosis

Key takeaways:

• Nearly all patients in the open-label extension of VISIONARY-MS showed MRI evidence of neuronal repair and remyelination.
• A presenter said CNM-Au8 achieved “a heretofore unseen clinical benefit” in MS.

SAN DIEGO — Data from an open-label extension of VISIONARY-MS support an association between gold nanocrystals and neuronal repair and remyelination in patients with stable multiple sclerosis and visual deficits, according to a presenter.

CNM-Au8 is an oral suspension of gold nanocrystals that is being studied as an adjunct to disease-modifying therapy in MS.

Previously, results of the randomized, double-blind, placebo-controlled VISIONARY-MS trial showed that CNM-Au8 improved visual function in patients with stable forms of MS who were on disease-modifying therapy and had a pre-existing visual deficit, Benjamin Greenberg, MD, professor and vice chair of clinical and translational research at UT Southwestern Medical Center, said during a late-breaking research presentation at the American Academy of Neurology Annual Meeting.

Greenberg and colleagues conducted an open-label extension of the trial to further examine evidence of neuronal repair and remyelination after treatment with 30 mg of CNM-Au8 in 55 individuals in Australia.

In the open-label extension, patients who were formerly assigned to placebo received CNM-Au8. Greenberg said these patients also experienced improvements in visual function over 2 years.

In a modified intent to treat population of 35 patients who were originally assigned to CNM-Au8, there was a mean improvement of 2.5 in low contrast letter acuity (LCLA) and 3.75 in Symbol Digit Modalities Test (SDMT) from the end of the trial’s initial double-blind phase (week 48) to week 144.

“This is an outcome that has not been seen before in prior therapies that have been used to improve function in multiple sclerosis,” Greenberg said.

Data further showed that 96% of participants who experienced a clinical response to CNM-Au8 also demonstrated evidence of neuronal repair and remyelination, as measured by diffusion tensor imaging (DTI) MRI.

Greenberg and colleagues also reported that multi-focal visual evoked potential confirmed faster and stronger brain signals in 91% of LCLA responders.

Finally, DTI MRI supported cognitive enhancements in 98% of SDMT responders based on improvements in axial diffusivity and magnetization transfer ratio.

“CNM-Au8 was able to achieve a heretofore unseen clinical benefit for stable MS patients … meeting its primary outcome of improved visual function and showed evidence of both structure and functional improvement over the course of the open-label extension,” Greenberg concluded.