The promise of third-generation recombinant therapy and gene therapy.
Recombinant factor VIII and IX products have well-established efficacy and safety records. However, concerns about the possibility of viral transmission have prompted efforts to develop recombinant products that are free of added human and animal proteins. The currently licensed second-generation recombinant factor VIII concentrates were introduced in 2000. Two new third-generation products, manufactured without any human- or animal-derived materials, are currently in development and clinical testing. As an alternative to exogenous factor replacement, gene therapy is under investigation for use in the treatment of hemophilia. Gene therapy involves the stable insertion of a functional gene for long-term expression and secretion of endogenous factor VIII or IX protein. Methods used to date have been based on retroviral, adenoviral, and adeno-associated viral vectors, as well as nonviral electroporation. Three phase I trials using these approaches have been completed as of 2002, and one more is ongoing. This article reviews the results of recent clinical studies investigating third-generation recombinant products and gene-based approaches to hemophilia treatment.
Manno
Catherine S
CS
Department of Pediatrics, University of Pennsylvania School of Medicine, and the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
D002478:Cells, Cultured / Q000637:transplantation; D002986:Clinical Trials as Topic; D005164:Factor IX / Q000096:biosynthesis / Q000235:genetics / Q000627:therapeutic use*; D005169:Factor VIII / Q000096:biosynthesis / Q000235:genetics / Q000627:therapeutic use*; D005347:Fibroblasts / Q000637:transplantation; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000627:therapeutic use; D006467:Hemophilia A / Q000188:drug therapy / Q000235:genetics / Q000628:therapy*; D002836:Hemophilia B / Q000188:drug therapy / Q000235:genetics / Q000628:therapy*; D022781:Hepatocytes / Q000637:transplantation; D006801:Humans; D008297:Male; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000627:therapeutic use; D012449:Safety; D013678:Technology, Pharmaceutical / Q000379:methods / Q000592:standards; D014162:Transfection; D016896:Treatment Outcome; D014777:Virus Diseases / Q000517:prevention & control / Q000635:transmission
D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; C078147:F8 protein, human; D005169:Factor VIII; D005164:Factor IX