World Federation of Hemophilia

• Maintaining high Factor VIII (FVIII) levels in people with hemophilia A provides significant clinical benefits, including reduced bleeding risk and better joint health preservation. • Despite advances in prophylactic treatment, standard-of-care prophylaxis does not completely prevent joint damage or chronic pain, with approximately 47% of hemophilia patients experiencing ongoing pain. • Recent innovations in hemophilia treatment, including extended half-life therapies, non-factor replacement options, and gene therapy, offer new approaches to sustaining higher FVIII levels and improving patient outcomes.

• Sanofi has voluntarily suspended its phase 3 clinical trials of fitusiran, an RNAi therapeutic for hemophilia A and B, following reports of non-fatal thrombotic events in study participants. • The safety pause, announced by major hemophilia patient organizations, marks the second significant safety setback for fitusiran, following a previous trial halt in 2017 due to a patient death. • The development impacts Sanofi's strategic pipeline, as fitusiran was positioned to compete with Roche's Hemlibra in the hemophilia treatment market.