RECRUITING

Phase 3, Open-label, Single-dose Study of CSL222 in Adolescent Male Subjects (≥ 12 to < 18 Years of Age) With Severe or Moderately Severe Hemophilia B

Conditions

Quick Navigation

Study Overview

This clinical trial focuses on testing the efficacy of different digital interventions to promote re-engagement in cancer-related long-term follow-up care for adolescent and young adult (AYA) survivors of childhood cancer.

Description

This is a phase 3, prospective, open-label, single-arm, single-dose, multicenter study investigating the efficacy, safety, and tolerability of CSL222 (AAV5-hFIXco-Padua) in adolescent male participants with severe or moderately severe hemophilia B.

Official Title

Phase 3, Open-label, Single-dose, Multicenter Study Investigating Efficacy, Safety, and Tolerability of CSL222 (Etranacogene Dezaparvovec) Administered to Adolescent Male Subjects (≥ 12 to < 18 Years of Age) With Severe or Moderately Severe Hemophilia B

Quick Facts

Study Start:2025-07-28

Study Completion:2033-10-24

Study Type:Not specified

Phase:Not Applicable

Enrollment:Not specified

Status:RECRUITING

Study ID

NCT07080905

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Ages Eligible for Study:138 Months to 206 Months

Sexes Eligible for Study:MALE

Accepts Healthy Volunteers:No

Standard Ages:CHILD

Inclusion Criteria	Exclusion Criteria
* Assigned male sex at birth * Aged \>=138 months to less than (\<) 206 months at the time of informed consent / assent. * Congenital hemophilia B with known severe or moderately severe FIX deficiency (less than or equal to \[\<=\] 2% of normal circulating FIX) for which the participant has been on continuous FIX prophylaxis. * On stable continuous FIX prophylaxis for at least 2 months before Screening. * Minimum of 75 previous exposure days of treatment with FIX protein before Screening. * Completed the Lead-in Period: minimum of 6 months (26 weeks) of lead-in data collected and eligibility has been confirmed. * Aged \>= 12 to \< 18 years at the time of CSL222 treatment.	* History of FIX inhibitors or positive FIX inhibitor test at Screening (based on central laboratory results). * Screening laboratory values (based on central laboratory results): * Total bilirubin greater than (\> 2) × the upper limit of normal (ULN). * ALT \> 2 × the ULN. * AST \> 2 x the ULN. * ALP \> 2 × the ULN. * Serum creatinine \> 2 × the ULN. * Hemoglobin \< 8 g/dL * Any condition other than hemophilia B resulting in an increased bleeding tendency. * Thrombocytopenia, defined as a platelet count below 50 × 10\^9/L, at screening (based on central laboratory results). * Any uncontrolled or untreated infection (human immunodeficiency virus, hepatitis C, etc) or any other significant concurrent, uncontrolled medical condition, as evaluated by the investigator, including, but not limited to renal, hepatic, cardiovascular, hematological, gastrointestinal, endocrine, pulmonary, neurological, cerebral, or psychiatric disease, alcoholism, drug dependency, or any other psychological disorder evaluated by the investigator to interfere with adherence to the Clinical Study Protocol procedures or with the degree of tolerance to CSL222. * Positive FIX inhibitor test at Visit L-Final (based on central laboratory results). * AAV5 NAb titer \> 1:900 as assessed at Visit LX (last visit before Visit L-Final). * Visit L-Final laboratory values (based on central laboratory results) of: * Total bilirubin \> 2 × the ULN * ALT \> 2 × the ULN. * AST \> 2 × the ULN. * ALP \> 2 × the ULN. * Serum creatinine \> 2 × the ULN. * Hemoglobin \< 8 g/dL. * Thrombocytopenia, defined as a platelet count below 50 × 10\^9/L, at Visit L-Final (based on central laboratory results).

Inclusion Criteria

Exclusion Criteria

* Assigned male sex at birth
* Aged \>=138 months to less than (\<) 206 months at the time of informed consent / assent.
* Congenital hemophilia B with known severe or moderately severe FIX deficiency (less than or equal to \[\<=\] 2% of normal circulating FIX) for which the participant has been on continuous FIX prophylaxis.
* On stable continuous FIX prophylaxis for at least 2 months before Screening.
* Minimum of 75 previous exposure days of treatment with FIX protein before Screening.
* Completed the Lead-in Period: minimum of 6 months (26 weeks) of lead-in data collected and eligibility has been confirmed.
* Aged \>= 12 to \< 18 years at the time of CSL222 treatment.

* History of FIX inhibitors or positive FIX inhibitor test at Screening (based on central laboratory results).
* Screening laboratory values (based on central laboratory results):
* Total bilirubin greater than (\> 2) × the upper limit of normal (ULN).
* ALT \> 2 × the ULN.
* AST \> 2 x the ULN.
* ALP \> 2 × the ULN.
* Serum creatinine \> 2 × the ULN.
* Hemoglobin \< 8 g/dL
* Any condition other than hemophilia B resulting in an increased bleeding tendency.
* Thrombocytopenia, defined as a platelet count below 50 × 10\^9/L, at screening (based on central laboratory results).
* Any uncontrolled or untreated infection (human immunodeficiency virus, hepatitis C, etc) or any other significant concurrent, uncontrolled medical condition, as evaluated by the investigator, including, but not limited to renal, hepatic, cardiovascular, hematological, gastrointestinal, endocrine, pulmonary, neurological, cerebral, or psychiatric disease, alcoholism, drug dependency, or any other psychological disorder evaluated by the investigator to interfere with adherence to the Clinical Study Protocol procedures or with the degree of tolerance to CSL222.
* Positive FIX inhibitor test at Visit L-Final (based on central laboratory results).
* AAV5 NAb titer \> 1:900 as assessed at Visit LX (last visit before Visit L-Final).
* Visit L-Final laboratory values (based on central laboratory results) of:
* Total bilirubin \> 2 × the ULN
* ALT \> 2 × the ULN.
* AST \> 2 × the ULN.
* ALP \> 2 × the ULN.
* Serum creatinine \> 2 × the ULN.
* Hemoglobin \< 8 g/dL.
* Thrombocytopenia, defined as a platelet count below 50 × 10\^9/L, at Visit L-Final (based on central laboratory results).

Contacts and Locations

Study Contact

Trial Registration Coordinator

CONTACT

1-610-878-4697

clinicaltrials@cslbehring.com

Principal Investigator

Study Director

STUDY_DIRECTOR

CSL Behring

Study Locations (Sites)

University of Florida - 84000399

Gainesville, Florida, 32611

United States

University of Michigan Medical Center - 84000491

Ann Arbor, Michigan, 48109

United States

Collaborators and Investigators

Sponsor: CSL Behring

Study Director, STUDY_DIRECTOR, CSL Behring

Study Record Dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Registration Dates

Study Start Date2025-07-28

Study Completion Date2033-10-24

Study Record Updates

Study Start Date2025-07-28

Study Completion Date2033-10-24

Terms related to this study

Additional Relevant MeSH Terms

Hemophilia B