A Study to Test a Medicine (Fitusiran) Injected Under the Skin for Preventing Bleeding Episodes in Male Adolescent or Adult Participants With Severe Hemophilia

NCT ID: NCT05662319

Last Updated: 2026-02-04

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

ACTIVE_NOT_RECRUITING

Clinical Phase

PHASE3

Total Enrollment

91 participants

Study Classification

INTERVENTIONAL

Study Start Date

2023-02-01

Study Completion Date

2029-01-25

Brief Summary

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This is a multicenter, multinational, open-label, one-way cross-over, Phase 3, single-arm study for treatment of hemophilia.

The purpose of this study is to measure the frequency of treated bleeding episodes with fitusiran in male adult and adolescent (≥12 years old) participants with hemophilia A or B, with or without inhibitory antibodies to factor VIII or IX who have switched from their prior standard of care treatment.

The total study duration will be up to approximately 50 months (200 weeks, 1 study month is equivalent to 4 weeks) and will include:

* A screening period up to approximately 60 days,
* A standard of care (SOC) period of approximately 6 study months (24 weeks),
* A fitusiran treatment period of approximately 36 study months (144 weeks),
* An antithrombin (AT) follow-up period of approximately 6 study months (24 weeks) but may be shorter or longer depending on individual participants AT recovery.

The frequency for telephone visits will be approximately every 2 weeks. For site visits the frequency will be approximately every 8 weeks during the SOC period and approximately every 4 weeks during the fitusiran treatment period. If applicable and if allowed by local regulation, home and/or remote visits may be conducted during the study

Detailed Description

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Conditions

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Hemophilia

Study Design

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Allocation Method

NA

Intervention Model

CROSSOVER

One way cross-over
Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

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All participants

In standard of care (SOC) period, participants will receive on-demand or prophylactic treatment with clotting factor concentrates (CFCs) or bypassing agents (BPAs) for 6 months (from Day -168 to Day -1). In fitusiran treatment period, participants will receive subcutaneous fitusiran prophylaxis once every other month (Q2M) or once monthly (QM) for 36 months (from Day 1 to Day 1009). In case of bleeding events participants will receive IV CFCs or BPAs. Participants may receive Antithrombin concentrate (ATIIIC) as rescue medicine.

.

Group Type EXPERIMENTAL

Fitusiran

Intervention Type DRUG

Pharmaceutical form: Solution for injection Route of administration: Subcutaneous (SC)

Clotting factor concentrates (CFC) or bypassing agents (BPA)

Intervention Type DRUG

* Coagulation factor VIII (ATC code: B02BD02)
* Coagulation factor IX (ATC code: B02BD04)
* Coagulation factor VIIa (ATC code: B02BD08)
* Factor VIII inhibitor bypassing activity (ATC code: B02BD03)

Pharmaceutical form: Solution for infusion Route of administration: Intravenous (IV)

Antithrombin concentrate (ATIIIC)

Intervention Type DRUG

Antithrombin III (ATC code: B01AB02) Pharmaceutical form: Solution for infusion Route of administration: Intravenous (IV)

Interventions

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Fitusiran

Pharmaceutical form: Solution for injection Route of administration: Subcutaneous (SC)

Intervention Type DRUG

Clotting factor concentrates (CFC) or bypassing agents (BPA)

* Coagulation factor VIII (ATC code: B02BD02)
* Coagulation factor IX (ATC code: B02BD04)
* Coagulation factor VIIa (ATC code: B02BD08)
* Factor VIII inhibitor bypassing activity (ATC code: B02BD03)

Pharmaceutical form: Solution for infusion Route of administration: Intravenous (IV)

Intervention Type DRUG

Antithrombin concentrate (ATIIIC)

Antithrombin III (ATC code: B01AB02) Pharmaceutical form: Solution for infusion Route of administration: Intravenous (IV)

Intervention Type DRUG

Eligibility Criteria

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Inclusion Criteria

* Diagnosis of severe congenital hemophilia A or B (FVIII \<1% or FIX level ≤2%) as evidenced by a central laboratory measurement at screening or documented medical record evidence.
* For participants currently not on prophylaxis (CFC or BPA on-demand): A minimum of 4 bleeding episodes requiring BPA (inhibitor participants) or CFC (non-inhibitor participants) treatment within the last 6 months prior to screening.
* Willing and able to comply with the study requirements and to provide written informed consent and assent in the case of participants under the age of legal consent, per local and national requirements

Exclusion Criteria

* Known co-existing bleeding disorders other than congenital hemophilia A or B
* History of arterial or venous thromboembolism, not associated with an indwelling venous access
* History of intolerance to SC injection(s).
* Current participation in immune tolerance induction therapy (ITI)
* Prior gene therapy
* Current or prior participation in a fitusiran trial
* Current or prior participation in a gene therapy trial
* Received an investigational drug or device within 30 days prior to the screening visit or within 5 half-lives of the investigational drug (or device) prior to the screening visit, whichever is longer
* Presence of clinically significant liver disease AT activity \<60% at Screening
* Co-existing thrombophilic disorder
* Hepatitis C virus antibody positive, except participants who have negative Hepatitis C viral load and no evidence of cirrhosis
* Presence of acute hepatitis, ie, hepatitis A, hepatitis E.
* Presence of acute or chronic hepatitis B infection
* Known to be HIV positive with CD4 count \<200 cells/μL.
* Reduced renal function The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.
Minimum Eligible Age

12 Years

Eligible Sex

MALE

Accepts Healthy Volunteers

No

Sponsors

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Sanofi

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Clinical Sciences & Operations

Role: STUDY_DIRECTOR

Sanofi

Locations

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Center for Inherited Blood Disorders (CIBD) Site Number : 8400012

Orange, California, United States

Site Status

M Health Fairview University of Minnesota Medical Center - West Bank- Site Number : 8400016

Minneapolis, Minnesota, United States

Site Status

Hackensack University Site Number : 8400009

Hackensack, New Jersey, United States

Site Status

Northwell Health Hemostasis and Thrombosis Center Site Number : 8400015

New Hyde Park, New York, United States

Site Status

University Hospitals of Cleveland Site Number : 8400001

Cleveland, Ohio, United States

Site Status

UPMC Children's Hospital of Pittsburgh-4401 Penn Ave Site Number : 8400017

Pittsburgh, Pennsylvania, United States

Site Status

Children's Medical Center Dallas- Site Number : 8400018

Dallas, Texas, United States

Site Status

Gulf States Hemophilia and Thrombophilia Center- Site Number : 8400002

Houston, Texas, United States

Site Status

Investigational Site Number : 1240001

Hamilton, Ontario, Canada

Site Status

Investigational Site Number : 1240002

Hamilton, Ontario, Canada

Site Status

Investigational Site Number : 1240004

Toronto, Ontario, Canada

Site Status

Investigational Site Number : 1560003

Beijing, , China

Site Status

Investigational Site Number : 1560001

Guangzhou, , China

Site Status

Investigational Site Number : 1560002

Jinan, , China

Site Status

Investigational Site Number : 2500003

Le Kremlin-Bicêtre, , France

Site Status

Investigational Site Number : 2500002

Lille, , France

Site Status

Investigational Site Number : 2500001

Paris, , France

Site Status

Investigational Site Number : 2760001

Berlin, , Germany

Site Status

Investigational Site Number : 2760002

Hamburg, , Germany

Site Status

Investigational Site Number : 3000001

Athens, , Greece

Site Status

Investigational Site Number : 3000002

Athens, , Greece

Site Status

Investigational Site Number : 3560004

Bangalore, , India

Site Status

Investigational Site Number : 3560007

Bhubaneswar, , India

Site Status

Investigational Site Number : 3560001

Pune-411011, , India

Site Status

Investigational Site Number : 3560006

Punjab, , India

Site Status

Investigational Site Number : 3560003

Vellore, , India

Site Status

Investigational Site Number : 3800003

Rozzano, Milano, Italy

Site Status

Investigational Site Number : 3800001

Milan, , Italy

Site Status

Investigational Site Number : 3920003

Nagoya, Aichi-ken, Japan

Site Status

Investigational Site Number : 3920001

Kashihara-shi, Nara, Japan

Site Status

Investigational Site Number : 3920002

Saitama-shi, Saitama, Japan

Site Status

Investigational Site Number : 4840002

Monterrey, Nuevo León, Mexico

Site Status

Investigational Site Number : 4840004

Chihuahua City, , Mexico

Site Status

Investigational Site Number : 4840001

Veracruz, , Mexico

Site Status

Investigational Site Number : 6160002

Krakow, Lesser Poland Voivodeship, Poland

Site Status

Investigational Site Number : 6160004

Lodz, Lódzkie, Poland

Site Status

Investigational Site Number : 6160001

Warsaw, Masovian Voivodeship, Poland

Site Status

Investigational Site Number : 6820002

Jeddah, , Saudi Arabia

Site Status

Investigational Site Number : 7100003

Johannesburg, , South Africa

Site Status

Investigational Site Number : 7100001

Parktown, , South Africa

Site Status

Investigational Site Number : 4100001

Seoul, Seoul-teukbyeolsi, South Korea

Site Status

Investigational Site Number : 4100002

Seoul, Seoul-teukbyeolsi, South Korea

Site Status

Investigational Site Number : 7240002

A Coruña, A Coruña [La Coruña], Spain

Site Status

Investigational Site Number : 7240003

Zaragoza, , Spain

Site Status

Investigational Site Number : 1580001

Taipei, , Taiwan

Site Status

Investigational Site Number : 1580003

Taipei, , Taiwan

Site Status

Investigational Site Number : 7920002

Adana, , Turkey (Türkiye)

Site Status

Investigational Site Number : 7920004

Akdeniz, , Turkey (Türkiye)

Site Status

Investigational Site Number : 7920001

Çapa, , Turkey (Türkiye)

Site Status

Investigational Site Number : 7920003

Izmir, , Turkey (Türkiye)

Site Status

Countries

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United States Canada China France Germany Greece India Italy Japan Mexico Poland Saudi Arabia South Africa South Korea Spain Taiwan Turkey (Türkiye)

Related Links

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Other Identifiers

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U1111-1275-9584

Identifier Type: REGISTRY

Identifier Source: secondary_id

2022-500221-33

Identifier Type: REGISTRY

Identifier Source: secondary_id

EFC17574

Identifier Type: -

Identifier Source: org_study_id

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