Sanofi has dosed the first patient in a Phase IIb clinical trial being conducted to assess SAR442168 (formerly known as PRN2246) for the treatment of relapsing multiple sclerosis.
This triggers a $30m milestone payment to Principia Biopharma, which has partnered with Sanofi to develop the drug candidate in multiple sclerosis and potentially other central nervous system (CNS) diseases.
SAR442168 is a covalent Bruton’s tyrosine kinase (BTK) inhibitor that crosses the blood-brain barrier and modulates immune cell function in the periphery, as well as the brain. This mechanism is believed to have the potential to treat CNS conditions.
The global, randomised, double-blind, placebo-controlled Phase IIb trial is designed to evaluate the dose response of once daily SAR442168 in around 120 adults with relapsing multiple sclerosis.
It will recruit patients with either at least one relapse in the previous year, two or more relapses during the previous two years, or one or more active Gadolinium (Gd)-enhancing brain lesion identified using magnetic resonance imaging (MRI) scan in the past six months before screening.
The primary outcome measure of the trial is the number of new Gd-enhancing T1 hyperintense lesions, while secondary outcomes include subjects experiencing adverse events.
In a prior Phase I trial, SAR442168 was found to be well-tolerated. Results also showed that BTK occupancy improved in a dose-dependent manner and all participants who underwent lumbar puncture achieved cerebral spinal fluid exposure.
Principia Biopharma president and CEO Martin Babler said: “One challenge in developing medicines for CNS disorders has been achieving sufficient blood–brain barrier penetration.
“We are very enthusiastic about the potential of our CNS-penetrating BTK inhibitor, especially because in a Phase I clinical trial, we demonstrated exposure of SAR442168 in the CNS, as well as BTK occupancy in peripheral blood.”
Principia granted Sanofi an exclusive licence in 2017 to develop and commercialise SAR442168 worldwide.