HemophiliaPhase 2/3ATLAS-PEDSNCT03974113
Fitusiran Prophylaxis in Male Pediatric Subjects Aged 1 to Less Than 12 Years With Hemophilia A or B
A Phase 2/3 study testing Fitusiran in people with Hemophilia, run by Genzyme, a Sanofi Company at 16 sites in 6 countries.
Trial summary
Primary Objective: To confirm appropriate dose levels of fitusiran when administered to male pediatric participants (ages 1 to <12 years of age) with severe hemophilia A or B Secondary Objectives: To characterize the safety and tolerability To determine fitusiran plasma concentrations at selected time points Read more about this study
- Who is it for?
- Ages 1 year to 11 years, men only
- Conditions the study is for
- Hemophilia
- What is being tested?
- Fitusiran
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 32 participants
- Where
- 16 sitesin 6 countries
- Study dates
- 28 Jan 2020to 4 Aug 2026
- Phase
- Phase 2/3
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 1 year to 11 years
- Men only
- No healthy volunteers
- Child
Who may be able to join
- Male, aged 1 to <12 years at the time of enrollment.
- Severe hemophilia A or B (Factor VIII (FVIII) <1% or Factor IX (FIX) ≤2%)
- Participants must have inhibitory antibodies to FVIII or FIX and must meet one of the following Nijmegen-modified Bethesda assay results criteria:
- Inhibitor titer of ≥0.6 BU/mL at screening, OR
- Inhibitor titer of <0.6 BU/mL at screening with medical record evidence of 2 consecutive titers ≥0.6 BU/mL, OR
- Inhibitor titer of <0.6 BU/mL at screening with medical record evidence of 1 inhibitor titer ≥0.6 BU/mL and a history of anamnestic response or severe allergic reaction (anaphylaxis or nephrotic syndrome)
Show all 9Show fewer
- Adequate peripheral venous access, as determined by the Investigator, to allow the blood draws required by the study protocol
- Weight requirements at the time of enrollment: 8 to <45 kg
- Willing and able to comply with the study requirements and to provide signed written informed consent obtained from parent(s)/legal guardian (hereinafter the "parent") and written or oral assent obtained from participant, per local and national requirements
Who cannot join
- Participants are excluded from the study if any of the following criteria apply:
- Known co-existing bleeding disorders other than hemophilia A or B
- Antithrombin (AT) activity <60% at Screening
- Co-existing thrombophilic disorder
- Clinically significant liver disease
- Active Hepatitis C virus infection
Show all 17Show fewer
- Acute or chronic Hepatitis B virus infection
- Acute Hepatitis A or hepatitis E infection
- HIV positive with a CD4 count of <400 cells/μL
- History of arterial or venous thromboembolism, unrelated to an indwelling venous access
- Inadequate renal function
- History of multiple drug allergies or history of allergic reaction to an oligonucleotide or N-Acetylgalactosamine (GalNAc)
- Subjects with central or peripheral indwelling catheters, with history of venous access complications leading to hospitalization and/or systemic anticoagulation therapy.
- History of intolerance to subcutaneous (SC) injection(s)
- Use of emicizumab (Hemlibra®) within 6 months prior to screening
- Any other conditions or comorbidities that would make the patient unsuitable for enrollment or could interfere with participation in or completion of the study, per Investigator judgment
- The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.
Trial locations and contacts
16 sites in 6 countries.
16 sites in 6 countries
United States4 sites
University Hospitals of Cleveland- Site Number : 8400007
Cleveland, Ohio, 44106
Hackensack University Medical Center- Site Number : 8400008
Hackensack, New Jersey, 07601
Penn State Milton S. Hershey Medical Center- Site Number : 8400006
Hershey, Pennsylvania, 17033
Children's Hospital Los Angeles Site Number : 8400002
Los Angeles, California, 90027
India4 sites
Investigational Site Number : 3560006
Bangalore, 560034
Investigational Site Number : 3560002
Mumbai, 400 022
Investigational Site Number : 3560001
Pune-411011, 411 011
Investigational Site Number : 3560004
Vellore, 632004
Turkey (Türkiye)3 sites
Investigational Site Number : 7920001
Adana, 01130
Investigational Site Number : 7920002
Istanbul, 34093
Investigational Site Number : 7920003
Izmir, TR-35100
Canada2 sites
Investigational Site Number : 1240001
Hamilton, Ontario, L8N 3Z5
Investigational Site Number : 1240002
Ottawa, Ontario, K1H 8L1
Italy2 sites
Investigational Site Number : 3800002
Florence, 50134
Investigational Site Number : 3800001
Milan, 20122
Spain1 site
Investigational Site Number : 7240002
Madrid, Madrid, Comunidad de, 28046
About this study
Official title: ATLAS-PEDS: An Open-label, Multinational Study of Fitusiran Prophylaxis in Male Pediatric Subjects Aged 1 to Less Than 12 Years With Hemophilia A or B
Primary Objective:
- To confirm appropriate dose levels of fitusiran when administered to male pediatric participants (ages 1 to <12 years of age) with severe hemophilia A or B
Secondary Objectives:
- To characterize the safety and tolerability
- To determine fitusiran plasma concentrations at selected time points
Read the detailed description
The estimated total time on study is up to 256 weeks for participants who roll over into the extension study and up to 280 weeks for participants who do not roll over into the extension study (due to the requirement for up to an additional 6 months of follow-up for monitoring of AT levels).
- Conditions
- Hemophilia
- Being tested
- Fitusiran
- Medical subject headings
- Hemophilia A
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
FitusiranDrug
Also called SAR439774
Pharmaceutical form:Solution for injection-Route of administration:Subcutaneous
| Study group | Role | What they receive |
|---|---|---|
| Fitusiran | Experimental | Participants will receive a selected dose of fitusiran at regular intervals, as per study protocol Receives: Drug: Fitusiran |
What is being measured
The primary outcome is the main question the study is designed to answer.
Plasma antithrombin (AT) activity levels
Characterize the AT activity at the optimal therapeutic dose
Measured: Day 1 to the AT analysis time point at the optimal therapeutic dose (approximately 256 weeks)
Secondary outcomes (2)
Number of participants reported with adverse events
Number of participants reported with treatment-emergent adverse events (TEAEs)
Measured: Up to 280 weeks (up to 256 weeks of treatment + up to 24 weeks of AT follow up)
Fitusiran plasma concentrations
Plasma samples will be collected for measurement of plasma concentrations of fitusiran at specific time points post dose on Day 1 and pre dose on Day 85
Measured: Day 1 and Day 85
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Jun 2019
- Study start28 Jan 2020
- Primary completion4 Aug 2026
- Study completion4 Aug 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HemophiliaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2/3
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 32 participants (actual)
Sponsor and investigators
- Lead sponsor
- Genzyme, a Sanofi Company
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Clinical Sciences & Operations, Study director, Sanofi
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03974113
- Sponsor's protocol ID
- EFC15467
- Other IDs
- U1111-1223-4368, 2024-512501-76, 2019-000679-18, 2019
- Acronym
- ATLAS-PEDS
- Status last verified
- Sep 2026
- First submitted
- 3 Jun 2019
- Last updated
- 28 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org
Study at a glance
From the registry record, last updated by the sponsor on 28 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- ATLAS-PEDS: An Open-label, Multinational Study of Fitusiran Prophylaxis in Male Pediatric Subjects Aged 1 to Less Than 12 Years With Hemophilia A or B
- ClinicalTrials.gov ID
- NCT03974113
- Acronym / sponsor ID
- ATLAS-PEDS / EFC15467
- Conditions
- Hemophilia
- Phase
- Phase 2/3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 32 participants (actual)
- Lead sponsor
- Genzyme, a Sanofi CompanyIndustry (pharma, biotech, devices)
- Study start
- 28 Jan 2020 (actual)
- Primary completion
- 4 Aug 2026 (actual)
- Study completion
- 4 Aug 2026 (actual)
- First posted
- 4 Jun 2019 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Primary Objective:
- To confirm appropriate dose levels of fitusiran when administered to male pediatric participants (ages 1 to <12 years of age) with severe hemophilia A or B
Secondary Objectives:
- To characterize the safety and tolerability
- To determine fitusiran plasma concentrations at selected time points
Detailed description
The estimated total time on study is up to 256 weeks for participants who roll over into the extension study and up to 280 weeks for participants who do not roll over into the extension study (due to the requirement for up to an additional 6 months of follow-up for monitoring of AT levels).
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Fitusiran | Experimental | Drug: FitusiranParticipants will receive a selected dose of fitusiran at regular intervals, as per study protocol |
Who may qualify
- Ages
- 1 year to 11 years
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (9 listed)
- Male, aged 1 to <12 years at the time of enrollment.
- Severe hemophilia A or B (Factor VIII (FVIII) <1% or Factor IX (FIX) ≤2%)
- Participants must have inhibitory antibodies to FVIII or FIX and must meet one of the following Nijmegen-modified Bethesda assay results criteria:
- Adequate peripheral venous access, as determined by the Investigator, to allow the blood draws required by the study protocol
- Weight requirements at the time of enrollment: 8 to <45 kg
Key exclusion criteria (17 listed)
- Known co-existing bleeding disorders other than hemophilia A or B
- Antithrombin (AT) activity <60% at Screening
- Co-existing thrombophilic disorder
- Clinically significant liver disease
- Active Hepatitis C virus infection
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| FitusiranAlso: SAR439774Pharmaceutical form:Solution for injection-Route of administration:Subcutaneous | Drug | Fitusiran |
Primary outcome
Plasma antithrombin (AT) activity levels
Time frame: Day 1 to the AT analysis time point at the optimal therapeutic dose (approximately 256 weeks)
Characterize the AT activity at the optimal therapeutic dose
2 secondary outcomes
Number of participants reported with adverse events
Time frame: Up to 280 weeks (up to 256 weeks of treatment + up to 24 weeks of AT follow up)
Fitusiran plasma concentrations
Time frame: Day 1 and Day 85
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Sep 2026.
- EFC15467 Plain Language Results SummaryLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org
Related trials for Hemophilia
RecruitingObservational study
The CACHE Study: Coronary Artery Care in HaEmophilia
Haemophilia, Cardiovascular Diseases
Active, not recruitingObservational study
A Study to Learn About the Study Medicine -Hympavzi in Congenital Hemophilia Patients Without Inhibitors in Japan.
Hemophilia A or B
RecruitingPhase 1/2
A Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Efficacy of NXT007 in Persons With Severe or Moderate Hemophilia A
Hemophilia A
Active, not recruitingPhase 3
A Study to Evaluate the Efficacy and Safety of Factor IX Gene Therapy With PF-06838435 in Adult Males With Moderately Severe to Severe Hemophilia B
Hemophilia B
Not yet recruiting
Safety of Intraosseous Anaesthesia in Children With Haemophilia
Haemophilia A, Haemophilia B
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Clinical Sciences & Operations study director
Sanofi
16 sites in 6 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2/3 study testing Fitusiran in people with Hemophilia, run by Genzyme, a Sanofi Company at 16 sites in 6 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 17 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 28 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 16 sites in United States, India, Turkey (Türkiye), Canada, Italy and 1 more country. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Plasma antithrombin (AT) activity levels (time frame: Day 1 to the AT analysis time point at the optimal therapeutic dose (approximately 256 weeks)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Sep 2026.