Multiple Sclerosis

Sanofi stock slumps after two setbacks on multiple-sclerosis drug

Sanofi shares dropped significantly following two negative developments regarding their multiple-sclerosis drug, tolebrutinib. One setback involved a partial clinical hold by the FDA on new patient enrollment for a different indication due to liver injury concerns, while the other pertained to less-than-expected efficacy from a rival drug, creating skepticism around the broader class of similar treatments.