The U.S. Food and Drug Administration, under priority review, is evaluating the regulatory submission of tolebrutinib to treat nonrelapsing secondary progressive multiple sclerosis and to slow disability accumulation independent of relapse activity in adult patients. The target action date for the FDA decision is Sept. 28.

If approved, tolebrutinib would be the first and only brain-penetrant BTK inhibitor to both treat nonrelapsing secondary progressive MS and slow disability accumulation independent of relapse activity. The results from the phase 3 studies HERCULES in nonrelapsing secondary progressive MS and GEMINI 1 and 2 in relapsing MS support the regulatory submission.

These findings, as well as additional clinical and preclinical studies, support the differentiated mechanism of tolebrutinib to target disability progression independent of relapse activity. Smoldering neuroinflammation is thought to represent a key inflammatory process in MS and is a critical driver of disability accumulation.

While tolebrutinib is currently under clinical investigation, its safety and efficacy have not been evaluated by any regulatory authority. The PERSEUS phase 3 study of tolebrutinib in patients with primary progressive MS is currently ongoing with study results anticipated later in the year.

Tolebrutinib is an investigational, oral, brain-penetrant, and bioactive Bruton’s tyrosine kinase inhibitor specifically designed to target smoldering neuroinflammation. Unlike currently approved MS therapies that primarily address peripheral inflammation, tolebrutinib uniquely crosses the blood-brain barrier to achieve therapeutic cerebrospinal fluid concentrations, allowing it to modulate B-lymphocytes and disease-linked microglia within the central nervous system. This mechanism is believed to address the underlying pathology of progressive MS by targeting the inflammatory processes that contribute to neurodegeneration and disability accumulation.

For more information on tolebrutinib clinical studies, visit clinicaltrials.gov.