Basel-based Swiss pharmaceutical major has announced that its experimental BTK inhibitor drug, fenebrutinib trial has met its primary endpoint by significantly reducing brain lesions in people with relapsing forms of multiple sclerosis, a chronic disease that affects more than 2.8 million people worldwide.

In a statement, the company informed that the trial results showed that oral fenebrutinib significantly reduced magnetic resonance imaging (MRI) markers of multiple sclerosis disease activity in the brain compared to placebo.

Furthermore, the company stated that pre-clinical data have shown fenebrutinib to be potent and highly selective, and it is the only reversible inhibitor currently in Phase III trials for multiple sclerosis.

Commenting on the trial findings, Roche’s Chief Medical Officer and Head of Global Product Development, Dr Levi Garraway, said, “I am encouraged by this clinical data for fenebrutinib, which is important news for people living with multiple sclerosis.”

“Fenebrutinib’s mechanism of action, which can inhibit both B cells and microglia, has the potential to both reduce multiple sclerosis disease activity, such as relapses and also impact disease progression,” he added.

Fenebrutinib is an experimental oral, reversible, and non-covalent Bruton's tyrosine kinase (BTK) inhibitor that inhibits BTK function.

BTK, also known as tyrosine-protein kinase BTK, is an enzyme that controls B-cell growth and activation as well as the activation of innate immune system myeloid lineage cells, including macrophages, which is a type of white blood cell that surrounds and kills microorganisms, removes dead cells, and stimulates the action of other immune system cells and microglia, the resident immune cells of the central nervous system.

 Pre-clinical results reveal that fenebrutinib is both powerful and selective, and it is the only reversible inhibitor now in Phase III trials for multiple sclerosis and is believed to be 130 times more selective for BTK than for other kinases.

These design features may be significant since strong selectivity and reversibility can potentially lower a molecule's off-target effects and contribute to long-term safety results.

Roche further informed that the research team plans to share the trial data during an upcoming medical meeting.