FDA investigating tolebrutinib under priority review

The US Food and Drug Administration (FDA) is evaluating under priority review the regulatory submission by French pharma major Sanofi (Euronext: SAN) of tolebrutinib to treat non-relapsing secondary progressive multiple sclerosis (nrSPMS) and to slow disability accumulation independent of relapse activity in adult patients.

The target action date for the FDA decision is September 28, 2025. A regulatory submission is also under review in the European Union, said Sanofi, whose shares edged up 1.5% on the news.

The company explained that the regulatory submissions in the USA and the EU are supported by the results from the Phase III studies HERCULES in nrSPMS and GEMINI 1 and 2 in relapsing MS (RMS). The findings from these studies, as well as additional clinical and pre-clinical studies, support the differentiated mechanism of tolebrutinib to target disability progression independent of relapse activity, and the scientific hypothesis that smoldering neuroinflammation represents a key inflammatory process in MS and is a critical driver of disability accumulation.