Sanofi slumps on expected delay to FDA's tolebrutinib review

Shares in Sanofi SASY.PA fall about 5% on expected delay to the FDA's decision on its non-relapsing secondary progressive multiple sclerosis (nrSPMS) drug tolebrutinib

Sanofi expects the treatment review to extend beyond Dec. 28, with further guidance from FDA expected in Q1 2026

"Given the failure of 3 trials for tolebrutinib ... we would be cautious on potential approval for tolebrutinib in nrSPMS," J.P. Morgan says

The shares are on track for their worst day since early Sept

They sit among the worst performers on Europe's STOXX 600 index .STOXX