Gene therapy for adults with Hemophilia B and specific antibodies

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This clinical trial evaluates the efficacy and safety of CSL222, a gene therapy designed for adults with severe or moderately severe Hemophilia B who have detectable neutralizing antibodies against adeno-associated virus serotype 5 (AAV5). Participants will receive CSL222 to assess its ability to reduce bleeding risks associated with their condition. The study focuses on individuals who have been on routine factor IX prophylaxis and have a history of exposure to factor replacement therapy. The trial aims to determine if this gene therapy can effectively manage their hemophilia symptoms.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Considered legally an adult, as defined by country regulations.
* Has 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 is on continuous routine FIX prophylaxis.
* Has 2 consecutive detectable AAV5 NAb titer results between Screening and Visit L-Final using a validated AAV5 NAb assay (based on central laboratory results).
* Has greater than (\>) 150 previous exposure days to FIX replacement therapy.
* Has been on stable FIX prophylaxis for at least 2 months before Screening.
* Has demonstrated capability to independently, accurately, and in a timely manner complete the eDiary during the Lead-in Period, as judged by the investigator.
* Acceptance to adhere to contraception guidelines.
* Able to provide informed consent after receipt of verbal and written information about the study.
* Investigator believes that the participant (or the participant's legally acceptable representative\[s\]) understands the nature, scope, and possible consequences of the study and is able to adhere to the study procedures.

Exclusion Criteria:

* History of FIX inhibitors or positive FIX inhibitor test at Prescreening, Screening or Visit L-Final (based on central laboratory results).
* Screening or Visit L-Final laboratory values (based on central laboratory results) of total bilirubin \> 2 × the upper limit of normal (ULN) (except if caused by Gilbert's syndrome).
* Screening or Visit L-Final laboratory values (based on central laboratory results) of any of the following laboratory abnormalities:

  1. ALT \> 2 × the ULN
  2. AST \> 2 × the ULN
  3. Alkaline phosphatase \> 2 × the ULN
  4. Serum creatinine \> 2 × the ULN
  5. Hemoglobin less than (\<) 8 g/dL
* Any condition other than hemophilia B resulting in an increased bleeding tendency.
* Thrombocytopenia, defined as a platelet count \<50 × 10\^9/L, at Screening or Visit L Final (based on central laboratory results).
* Any uncontrolled or untreated infection (human immunodeficiency virus \[HIV\], hepatitis B virus \[HBV\] and hepatitis C virus \[HCV\], or any other significant concurrent, uncontrolled medical condition 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.
* Known history of allergy to corticosteroids or known medical condition that would require chronic administration of oral corticosteroids.
* Known uncontrolled allergic conditions or allergy / hypersensitivity to any component of the CSL222 excipients (ie, sucrose, potassium chloride, potassium dihydrogen phosphate, sodium chloride, and disodium hydrogen phosphate).
* Previous AAV5 gene therapy treatment.
* Receipt of an experimental agent or device within 60 days before Screening until the end of the study.

Where it's running

• University of California, San Diego (UCSD)
  San Diego, California, United States Recruiting
• University of Michigan
  Ann Arbor, Michigan, United States Recruiting
• Hemophilia Center of Western Pennsylvania (HCWP)
  Pittsburgh, Pennsylvania, United States Recruiting
• The University of Texas Health Science Center at Houston
  Houston, Texas, United States Recruiting
• Royal Prince Alfred Hospital
  Camperdown, New South Wales, Australia Recruiting
• Royal Brisbane Hospital
  Herston, Queensland, Australia Recruiting

Study contacts

• Study coordinator: Trial Registration Coordinator
• Email: clinicaltrials@cslbehring.com
• Phone: 1-610-878-4697

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• SR604: a new treatment tested in adults with Hemophilia A/B or congenital Factor VII deficiency

  This study tests a single and multiple doses of SR604 to see if it is safe and effective for adults with Hemophilia A or B, with or without inhibitors, and for those with congenital Factor VII deficiency.

  Recruiting at 7 sites Phase 1/2 Shanghai RAAS Blood Products Co., Ltd. · Changsha and 8 other locations · NCT07644832

• Single-dose CSL222 gene therapy for adolescent males (12–17) with severe or moderately severe hemophilia B.

  This will give a single dose of CSL222 gene therapy to adolescent males with severe or moderately severe hemophilia B to see if it raises factor IX activity and reduces bleeding.

  Recruiting at 17 sites Phase 3 CSL Behring · Orange, California and 16 other locations · NCT07080905

• ATHNdataset registry for people with bleeding and clotting disorders

  This registry collects health, treatment, and patient-reported information from people with bleeding and clotting disorders seen at ATHN-affiliated centers to help improve care and outcomes.

  Recruiting American Thrombosis and Hemostasis Network · Hickory, North Carolina · NCT06820515

• Is synovial proliferation in haemophilia joints active or inactive?

  This project will test whether ultrasound, MRI and elastography can tell if subclinical synovial proliferation in people with severe haemophilia is currently active so clinicians can treat earlier.

  Recruiting UMC Utrecht · Utrecht · NCT06809972

• Observational study of blood clotting and bleeding disorders in Chinese patients

  This study looks at blood clotting and bleeding problems in Chinese patients to see how common they are and what factors might affect them.

  Recruiting Peking University People's Hospital · Beijing, Beijing Municipality and 4 other locations · NCT06727669

• Comparing ANB-002 to standard treatment for hemophilia B

  This study is testing a new treatment called ANB-002 to see if it works as well as the standard treatment for adults with hemophilia B who have low FIX activity and no FIX inhibitors.

  Recruiting at 11 sites Phase 3 Biocad · Chelyabinsk and 13 other locations · NCT06700096

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.