This is a Phase I study. This research study is being conducted to find new ways to treat severe hemophilia A. This study is a gene therapy study. Gene therapy is an experimental way to introduce, into a person's cells, specific genetic material. A gene can be delivered/introduced into a cell using a carrier known as a "vector." In this study, a virus (lentivirus), the "vector", is used to introduce or deliver a gene that creates and stores a protein Factor VIII (FVIII) in your platelets. These platelets are made from stem cells (mother cells for your bone marrow) that are removed from your blood by a procedure called apheresis. This research study will take some of the patient's own stem cells, from the apheresis procedure, and genetically modify them using the vector in order to make them produce FVIII in platelets that arise from the stem cells. They will then give the genetically modified stem cells back to the patient so that they can possibly create platelets that produce and store Factor VIII on their own.
Name: Auto CD34+PBSC, transduced with a lentiviral vector encoding the B domain deleted from of human coagulation factor VIIIDescription: Reduced intensity conditioning with melphalan and fludarabine, followed by a single infusion of autologous CD34+PBSC, transduced with a lentiviral vector (-889ITGA2B-BDDFVIII-WPTS(MUT6)(VSVg)) also known as (Pleightlet(MUT6)) encoding the B domain deleted from of human coagulation factor VIII (BDDFVIII) in up to five hemophilia A patients with inhibitors to FVIII The infusion volume of transduced cells will not exceed 20 ml/kg body weight.Type: Biological
Autologous CD34+PBSC transduced with a lentiviral vector
Description: Assessed by availability of ≥4x106 transduced clinical grade CD34+PBSC per kg meeting release criteria for infusion; undetectable microbiological contamination and cell viability ≥70%.Measure: Number of enrolled participants with adequate gene transduced hematopoietic stem cells for FVIII gene therapy infusion Time: Through study completion, an average of 4 years
Description: Number of events meeting CTCAE criteria grade 3 or 4 toxicityMeasure: Incidence of toxicity from gene therapy Time: Within 3 months of gene therapy infusion
Single Group Assignment
There is one SNP
Those with a known co-existing clinically significant thrombophilic disorder, or as determined by the presence of any of the below identified on screening laboratory assessments: - FV Leiden - Protein S deficiency - Protein C deficiency - Prothrombin mutation (G20210A) - D-dimer >3 x the upper limit of normal (ULN) at Screening All known patients with the above and any patient with a personal or significant family history of thrombotic events (DVT, PE, arterial clots) as deemed by the principal investigator will be screened for the above disorders. --- G20210A ---