Fitusiran Prophylaxis in Male Pediatric Subjects Aged 1 to Less Than 12 Years With Hemophilia A or B (ATLAS-PEDS)

Genzyme

Status and phase

Active, not recruiting

Phase 3

Conditions

Hemophilia

Treatments

Drug: Fitusiran

Study type

Interventional

Funder types

Industry

Identifiers

NCT03974113

EFC15467

2019-000679-18 (EudraCT Number)

U1111-1223-4368 (Other Identifier)

Details and patient eligibility

About

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

Full 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).

Enrollment

32 patients

Sex

Male

Ages

1 to 11 years old

Volunteers

No Healthy Volunteers

Inclusion criteria

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)
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

Exclusion criteria

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
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