FDA slaps partial clinical hold on Phase III tolebrutinib trials

The US Food and Drug Administration (FDA) has placed Phase III studies of tolebrutinib in multiple sclerosis (MS) and myasthenia gravis on partial clinical hold, said French pharma major Sanofi (Euronext: SAN), whose shares were down 4.3% at 96.55 euros as trading moved towards close today.

As a result, new enrollment in the USA is paused, and participants in the USA who have been in the trial for fewer than 60 days shall suspend study drug. Importantly, US participants who have completed at least 60-days in the trial should continue treatment.

Sanofi acquired rights to the drug along with its $3.7 billion takeover of California-based Principia Biopharma in 2020.