Sanofi disclosed mixed Phase 3 readouts for its glucosylceramide synthase inhibitor venglustat: the compound met primary and multiple secondary endpoints in a Gaucher disease trial but failed to show superiority in a separate Fabry disease study. The divergent outcomes reflect disease‑specific biology and complicate Sanofi’s development and commercialization planning for the program. Company statements indicate the Gaucher result will support regulatory and clinical work in that indication while the negative Fabry data will prompt re‑evaluation of clinical strategy and resource allocation. The program’s mixed profile highlights the challenges of advancing a single small molecule across distinct lysosomal disorders.