Weekly efanesoctocog alfa for hemophilia A with joint synovial hypertrophy

Prospective Interventional Study of Effectiveness of Efanesoctocog Alfa Prophylaxis on Synovial Hypertrophy in Patients With Hemophilia A

This trial tests whether taking efanesoctocog alfa once a week for 12 months can reduce synovial hypertrophy in people aged 12 and older with moderate to severe hemophilia A.

Quick facts

• Phase: Phase 4
• Study type: Interventional
• Enrollment: 35 (estimated)
• Ages: 12 Years and up
• Sex: All
• Sponsor: Sanofi (Industry-sponsored)
• Locations: 13 sites (Los Angeles, California and 12 other locations)
• Trial ID: NCT06941870 on ClinicalTrials.gov

What this trial studies

This Phase 4, multi-center interventional trial gives participants weekly prophylaxis with efanesoctocog alfa for approximately 12 months and monitors changes in synovial hypertrophy in affected joints. Eligible joints are identified by a HEAD‑US synovitis score of 1 or 2 at baseline, and joints with planned major orthopedic procedures are excluded. The study uses serial imaging and clinical follow-up to document any changes in synovial thickness and related joint health over the treatment period. Sites are in Los Angeles, Indianapolis, and Iowa City, and the sponsor is Sanofi.

Who should consider this trial

Good fit: Ideal candidates are people aged 12 or older with moderate to severe hemophilia A (≤5% FVIII activity) who have at least one joint with synovial hypertrophy (HEAD‑US synovitis score 1 or 2) and no planned major orthopedic procedures for that joint.

Not a fit: People without synovial hypertrophy, with mild hemophilia A, or those who recently had or plan major orthopedic joint surgery are unlikely to benefit from this specific intervention.

Why it matters

Potential benefit: If successful, weekly efanesoctocog alfa could shrink hypertrophic synovium and help preserve joint health and function in people with hemophilia A.

How similar studies have performed: Efanesoctocog alfa has demonstrated substantial reductions in bleeding rates and improved factor troughs in earlier trials, but direct evidence that it reverses established synovial hypertrophy is limited.

Eligibility criteria

Inclusion Criteria: Participant is diagnosed with moderate to severe hemophilia A (defined as less than or equal to (≤)5 percent (%) of endogenous FVIII clotting activity) at the time of consent/assent.

Participant is more than or equal to (≥)12 years old at the time of consent/assent.

Participant has existing synovial hypertrophy, defined as at least 1 eligible\* joint by the HEAD-US score (Synovitis score: 1 or 2) at the time of consent/assent.

Participant has at least 1 eligible\* joint without planned future major orthopedic procedures (example, arthroscopic synovectomy, radioisotopic or chemical synoviorthesis), or major orthopedic procedures in the past 3 months prior to the screening visit (Visit 1).

\*An eligible joint is a joint with existing synovial hypertrophy, as defined by a HEAD-US synovitis score of 1 or 2, considering hypertrophic synovium as an indication of the presence of synovitis Participant has received prophylactic treatment with hemophilia prophylaxis prescriptions in the last 12 months prior to the baseline visit (Visit 2).

Participant is capable of understanding the written Informed Consent Form (ICF)/assent form, provides a signed and witnessed written ICF/assent form, and agrees to comply with the protocol requirements.

If male, no contraceptive measures are required for this study.

If female, is not pregnant or breastfeeding, and one of the following conditions applies:

Is a women of nonchildbearing potential (WONCBP) Is a women of childbearing potential (WOCBP) and agrees to use a highly effective contraceptive method, with a failure rate of less than (\<)1 percent during the study treatment period (at least until the Week 52/ End of Treatment \[EoT\] visit).

A WOCBP must have a negative serum pregnancy test at the screening visit (Visit 1) Exclusion Criteria: Participants are excluded from the study if any of the following criteria apply:

Has other associated clotting disorders at the time of consent/assent. Is already under efanesoctocog alfa treatment. Has a current diagnosis of an factor VIII (FVIII) inhibitor, defined as inhibitor titer ≥0.60 BU/mL.

Has ITI within the last 2 years prior to the baseline visit (Visit 2). Has been enrolled in a concurrent clinical interventional study or exposed to other investigational drug(s) within 3 months prior to screening for this study.

Is currently in an institution because of regulatory or legal order (that is, is a prisoner or a patient who is legally institutionalized).

Is not suitable for participation, whatever the reason, as judged by the investigator, including medical or clinical conditions, or patients potentially at risk of noncompliance to study procedures.

Is an employee or family member of the investigator or site personnel. Is involved in a specific situation during study implementation or the course of the study that may raise ethics considerations.

Has hypersensitivity to efanesoctocog alfa or its components or any of its excipients that, in the opinion of the investigator, contraindicates participation in the study.

Where this trial is running

Los Angeles, California and 12 other locations

• Orthopedic Institute for Children- Site Number : 8400009 — Los Angeles, California, United States (Recruiting)
• Innovative Hematology, Inc.- Site Number : 8400006 — Indianapolis, Indiana, United States (Recruiting)
• University of Iowa- Site Number : 8400004 — Iowa City, Iowa, United States (Recruiting)
• Ohio State University Hospital East- Site Number : 8400001 — Columbus, Ohio, United States (Recruiting)
• Investigational Site Number : 1240003 — Hamilton, Ontario, Canada (Recruiting)
• Investigational Site Number : 1240004 — Hamilton, Ontario, Canada (Recruiting)
• Investigational Site Number : 3920003 — Kawasaki, Kanagawa, Japan (Recruiting)
• Investigational Site Number : 3920002 — Hiroshima, Japan (Recruiting)
• Investigational Site Number : 3920001 — Saitama, Japan (Recruiting)
• Investigational Site Number : 3920004 — Tokyo, Japan (Recruiting)
• Investigational Site Number : 1580003 — Kaohsiung City, Taiwan (Recruiting)
• Investigational Site Number : 1580001 — Taichung, Taiwan (Recruiting)
• Investigational Site Number : 1580002 — Taipei, Taiwan (Recruiting)

Study contacts

• Study coordinator: Trial Transparency email recommended (Toll free for US & Canada)

Conditions Factor VIII Deficiency