A Phase 1/2 interventional study of AskBio009 in Hemophilia B, sponsored by Baxalta now part of Shire. Active, not recruiting at 15 sites in United States. Open to male participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-03-20.
Sponsored by Baxalta now part of Shire (part of Takeda) · Phase 1/2, Interventional, and Treatment
The purpose of this study is to evaluate the safety of single ascending IV doses of a Factor IX (FIX) Gene Therapy in up to 16 Adults with Hemophilia B.
Hemophilia B is a genetic X-linked bleeding disorder caused by a deficiency in blood-clotting Factor IX (FIX) activity. FIX is synthesized in the liver and circulates in the blood as a proenzyme. Current treatment for hemophilia B is based on replacement of the deficient FIX with IV injections of recombinant FIX protein prophylactically or as needed to treat bleeding episodes. This clinical program will test a gene transfer approach involving the use of a gene delivery vector carrying a FIX gene. This first-in-humans study is intended to evaluate the safety, kinetics, and if possible, the dose of AskBio009 required to achieve stable plasma FIX activity between 10% and 40% of normal activity.
292 studies on the registry are indexed under Hemophilia B; 51 are open to participants now.
This study's enrollment of 30 is above the median of 26 across 171 interventional studies indexed under Hemophilia B.
Browse Hemophilia B studies →Baxalta now part of Shire is the lead sponsor of 111 studies on the registry; none are open to participants now.
Of its 18 completed or terminated interventional studies of FDA-regulated products, 16 (89%) have results posted.
First submitted before Baxalta became part of Takeda.
Counted across the registry records on this site, refreshed daily.
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.
Exclusion Criteria:
Markers of hepatic inflammation or overt or occult cirrhosis as evidenced by one or more of the following:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Single Dose of a Self-Complementing Optimized Adeno-associated Virus (AAV) Serotype 8 Factor IX Gene Therapy
Biological: AskBio009
Single dose IV injection
Also known as: BAX 335
Number of patients experiencing treatment-related adverse events by dose group
Time frame: Infusion to Week 3 and Infusion to end of study
Change from baseline in clinical laboratory evaluations
Time frame: Change from baseline at week 3 and change from baseline at the end of study
Changes from Baseline in FIX activity levels, FIX protein levels, and Bleeding Episode Severity & Frequency
Time frame: At multiple timepoints from pre-dose through up to 5 years post-dose
Immune Response to AskBio009
Time frame: At multiple timepoints from pre-dose through up to 5 years post-dose
Detection of AskBio009 genomes in blood, saliva, urine, stool, and semen
Time frame: At multiple timepoints from pre-dose through up to 1 years post-dose
Plan to share: Yes — Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
Access criteria: IPD from eligible studies will be shared with qualified researchers according to the criteria and process described on https://vivli.org/ourmember/takeda/. For approved requests, the researchers will be provided access to anonymized data (to respect patient privacy in line with applicable laws and regulations) and with information necessary to address the research objectives under the terms of a data sharing agreement.
Data sharing details ↗ · vivli.org
Started Feb 2013 (actual). Primary completion is estimated for Jan 2030, 203 months after the start.
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This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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