An observational study in Hemophilia A or B, sponsored by Sanofi. Not yet recruiting at 1 site in United States. Open to participants aged 12 Years and older. Per ClinicalTrials.gov, last updated 2026-10-26.
Sponsored by Sanofi · Observational
This is a real-world, mixed-methods observational study conducted among adolescent (ages 12-17 years) and adult participants diagnosed with hemophilia A or B, with or without Factor VIII (FVIII) or Factor IX (FIX) inhibitors, who are treated with fitusiran. The study includes a prospective longitudinal cohort (Cohort 1) and a cross-sectional cohort (Cohort 2).
Data collection includes patient-reported outcomes via online surveys, qualitative interviews conducted via teleconference, and electronic medical record (EMR) review to describe real-world patient experiences, treatment satisfaction, adherence, and clinical management of fitusiran.
886 studies on the registry are indexed under Hemophilia A; 139 are open to participants now.
This study's planned enrollment of 100 is above the median of 80 across 322 observational studies indexed under Hemophilia A.
Browse Hemophilia A studies →Sanofi is the lead sponsor of 1,548 studies on the registry; 88 are open to participants now.
Of its 204 completed or terminated interventional studies of FDA-regulated products, 122 (60%) have results posted.
Counted across the registry records on this site, refreshed daily.
This study aims to enroll up to an estimated 100 participants across cohorts.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Participant is ≥ 12 years of age at the time of consent
-- Signed written informed consent by participants who are legally adults (i.e., have reached the age of majority as defined by local law) or legally authorized representative (e.g., parent) and assent (for participants under the age of majority by local law)
Participant is using fitusiran (QFITLIA) for:
Participant is willing and able to participate in:
Exclusion Criteria:
The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.
Participants who have started fitusiran treatment within 0 to 5 months before baseline.
Participants who have started fitusiran treatment within 9 to 15 months before baseline.
Patient-reported satisfaction with fitusiran measured by patient treatment preference questionnaire: Cohort 1 & 2
The Patient Treatment Preference Questionnaire is a five-item instrument designed to evaluate treatment preferences. Items assess satisfaction with treatment, preferred treatment options, and willingness to continue treatment.
Time frame: Over 12 months of treatment with fitusiran
Patient-reported satisfaction with previous treatment measured by bespoke qualitative patient survey and interview: Cohorts 1 & 2
The Bespoke survey covering patient satisfaction and transition to, or changes made while taking Fitusiran.
Time frame: Over 12 months of treatment with fitusiran
Patient-reported adherence to fitusiran measured by patient treatment preference questionnaire: Cohort 1
The Patient Treatment Preference Questionnaire is a five-item instrument designed to evaluate treatment preferences. Items assess satisfaction with treatment, preferred treatment options, and willingness to continue treatment.
Time frame: Over 12 months of treatment with fitusiran
Patient-reported reasons for switching to or starting and staying on fitusiran assessed through bespoke qualitative patient survey and interview: Cohort 1 & 2
The Bespoke survey covering patient satisfaction and transition to, or changes made while taking Fitusiran.
Time frame: Over 12 months of treatment with fitusiran
Patient-reported disadvantages of using fitusiran assessed by bespoke qualitative patient survey and interview: Cohort 1 & 2
The Bespoke survey covering patient satisfaction and transition to, or changes made while taking Fitusiran.
Time frame: Over 12 months of treatment with fitusiran
Patient-reported willingness to continue fitusiran assessed through patient treatment preference questionnaire: Cohort 1 & 2
The Patient Treatment Preference Questionnaire is a five-item instrument designed to evaluate treatment preferences. Items assess satisfaction with treatment, preferred treatment options, and willingness to continue treatment.
Time frame: Over 12 months of treatment with fitusiran
Change from baseline in patient-reported physical activity since starting fitusiran using PROBE questionnaire, EQ-5D-5L, EQ-5D-Y-3L: Cohort 1
The Patient-Reported Outcomes Burdens and Experiences (PROBE) questionnaire is designed to assess the health status, treatment experiences, and QoL of individuals with hemophilia. Total PROBE score ranges from 0 to 1; a lower score means higher burden. The EQ-5D-5L is an adult measure of general health-related quality of life and health status, composed of five items and a visual analogue scale (VAS). VAS score ranges from 0 (worst imaginable health) to 100 (best imaginable health). The EQ-5D-Y-3L assesses the same health domains as the EQ-5D-5L but uses simplified, child-friendly language. VAS score ranges from 0 (worst imaginable health) to 100 (best imaginable health).
Time frame: Over 12 months of treatment with fitusiran
Change from baseline in patient-reported joint health since starting fitusiran using PROBE questionnaire, EQ-5D-5L, EQ-5D-Y-3L: Cohort 1
The Patient-Reported Outcomes Burdens and Experiences (PROBE) questionnaire is designed to assess the health status, treatment experiences, and QoL of individuals with hemophilia. Total PROBE score ranges from 0 to 1; a lower score means higher burden. The EQ-5D-5L is an adult measure of general health-related quality of life and health status, composed of five items and a visual analogue scale (VAS). VAS score ranges from 0 (worst imaginable health) to 100 (best imaginable health). The EQ-5D-Y-3L assesses the same health domains as the EQ-5D-5L but uses simplified, child-friendly language. VAS score ranges from 0 (worst imaginable health) to 100 (best imaginable health).
Time frame: Over 12 months of treatment with fitusiran
Changes in patient reported outcomes, burdens and experiences (PROBE): Cohort 1
The Patient-Reported Outcomes Burdens and Experiences (PROBE) questionnaire assesses health status, treatment experiences, and quality of life of individuals with hemophilia. Total PROBE score ranges from 0 to 1; a lower score means higher burden.
Time frame: Over 12 months of treatment with fitusiran
Changes in EQ-5D-5L (for adult participants): Cohort 1 & 2
The EQ-5D-5L is an adult measure of general health-related quality of life and health status, composed of five items and a visual analogue scale (VAS). VAS score ranges from 0 (worst imaginable health) to 100 (best imaginable health).
Time frame: Over 12 months of treatment with fitusiran
Changes in EQ-5D-Y-3L (for adolescent participants): Cohort 1 & 2
The EQ-5D-Y-3L is a tool to measure general health-related quality of life and health status in child-friendly language. It is composed of five items and a visual analogue scale (VAS). VAS score ranges from 0 (worst imaginable health) to 100 (best imaginable health).
Time frame: Over 12 months of treatment with fitusiran
Patient-reported change in work or school attendance and productivity since starting fitusiran via the Work Productivity and Activity Impairment Questionnaire plus Classroom Impairment Questionnaire adapted for hemophilia patients (WPAI+CIQ:HS): Cohort 1
The Work Productivity and Activity Impairment Questionnaire plus Classroom Impairment Questions for Hemophilia Specific (WPAI+CIQ:HS). Score ranged from 0-10; where 0 indicates less productivity and 10 indicates greater impairment.
Time frame: Over 12 months of treatment with fitusiran
Changes in patient-reported hemophilia disease and treatment-related pain since starting fitusiran measured by PROMIS v2.0 - pain intensity 3a: Cohort 1
The Patient-Reported Outcomes Measurement Information System (PROMIS) v2.0 Pain Intensity 3a short form is a patient-reported measure of hemophilia disease and treatment-related pain intensity. Score range from 3 to 15, the higher the score, the greater the pain.
Time frame: Over 12 months of treatment with fitusiran
Changes in patient-reported mental health status, such as stress and anxiety, since starting fitusiran, measured by the bespoke qualitative patient survey and interview: Cohorts 1 & 2
The Bespoke survey covering patient satisfaction and transition to, or changes made while taking Fitusiran.
Time frame: Over 12 months of treatment with fitusiran
Number of patient-reported antithrombin (AT) test and associated impacts measured by the bespoke qualitative patient survey and interview: Cohort 1 & 2
The Bespoke survey covering patient satisfaction and transition to, or changes made while taking Fitusiran.
Time frame: Over 12 months of treatment with fitusiran
Number of patient-reported liver function test (LFT) and associated impacts measured by the bespoke qualitative patient survey and interview: Cohort 1 & 2
The Bespoke survey covering patient satisfaction and transition to, or changes made while taking Fitusiran.
Time frame: Over 12 months of treatment with fitusiran
Number of patients receiving different dose of fitusiran and rate of dosing regimen changes since starting fitusiran: Cohort 1 & 2
Time frame: Over 12 months of treatment with fitusiran
Frequency of antithrombin (AT) and liver function test (LFT) performed: Cohort 1 & 2
Time frame: Over 12 months of treatment with fitusiran
Frequency and type of treatment access barriers among patients initiating fitusiran: Cohort 1 & 2
Time frame: Over 12 months of treatment with fitusiran
Patient-reported treatment satisfaction and compliance related to dose changes and longer dose adjustment period using patient treatment preference questionnaire and qualitative patient interview: Cohort 1 & 2
The Patient Treatment Preference Questionnaire is a five-item instrument designed to evaluate treatment preferences. Items assess satisfaction with treatment, preferred treatment options, and willingness to continue treatment.
Time frame: Over 12 months of treatment with fitusiran
Plan to share: 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
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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