NCT06145373

A Study to Test a Medicine (Fitusiran) for Preventing Bleeds in People With Severe Hemophilia Who Previously Received Preventive Treatment With Emicizumab

An Open-label, Single-arm Treatment Study to Investigate the Safety and Tolerability of Switching From Emicizumab to Fitusiran Prophylaxis in Male Participants Aged ≥12 Years of Age With Severe Hemophilia A, With or Without Inhibitors

• Status: Recruiting
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 20 (estimated)
• Sponsor: Sanofi · Industry
• Sex: Male
• Age: 12 Years
• Healthy volunteers: Not accepted

Summary

This is an exploratory, single group, Phase 4, study to assess treatment with fitusiran prophylaxis after switching from emicizumab prophylaxis. This study aims to evaluate the safety and tolerability of switching to fitusiran after a transition period from the last dose of emicizumab. The study will be conducted in male participants with severe hemophilia A, with or without inhibitors, aged ≥12 years, who were previously receiving emicizumab prophylaxis. Study details include: * The study duration will be up to approximately 28 months: * There will be an approximately 2-month screening period. * There will be an approximately 2-month period before fitusiran treatment starts (pre-fitusiran treatment period) * The fitusiran treatment duration will be up to 18-months (fitusiran treatment period) * The antithrombin (AT) follow-up (FU) period will be approximately 6 months after the last dose of fitusiran (during which the AT activity level will be monitored at approximately monthly intervals following the final fitusiran dose until AT activity levels return to at least 60%). * The study site visits are scheduled at monthly/ every 2 months intervals of 28 days (4 weeks) / 56 days (8 weeks), respectively, during the fitusiran treatment period.

Conditions

• Hemophilia A

Interventions

Type	Name	Description
DRUG	Fitusiran (SAR439774)	Pharmaceutical form:Solution for injection-Route of administration:Subcutaneous (SC) injection
BIOLOGICAL	Clotting factor concentrates (CFC) or bypassing agents (BPA)	Pharmaceutical form: Solution for injection-Route of administration: Intravenous (IV) injection
BIOLOGICAL	Antithrombin concentrate (ATIIIC)	Pharmaceutical form:Solution for injection-Route of administration:Intravenous (IV) injection
BIOLOGICAL	Emicizumab	Pharmaceutical form:Solution for injection-Route of administration:SC injection

Timeline

• Start date: 2024-03-01
• Primary completion: 2026-09-19
• Completion: 2029-11-30
• First posted: 2023-11-24
• Last updated: 2025-09-30

Locations

2 sites across 2 countries: United States, Taiwan

Regulatory

• FDA-regulated drug study