Preclinical gene correction of hemophilia A

A型血友病临床前基因校正

• 批准号: 7788859
• 负责人: HAIG H. KAZAZIAN
• 金额: $ 8.16万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-04-06 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7788859
• 关键词: 7,7' -dimethoxy-(4,4' -bi-1,3-benzodioxole)-5,5' -dicarboxylic acid dimethyl ester; A Mouse; Adult; Animal Model; Animals; Antibodies; Antibody Formation; B-Lymphocytes; Canis familiaris; Capsid; Clinical Trials; Complementary DNA; Development; Dose; Effectiveness; Gene Delivery; Hemophilia A; Immune response; Infusion procedures; Intravenous; Intravenous infusion procedures; Light; Liver; Mediating; Monitor; Morbidity - disease rate; Plasma; Portal vein structure; Proteins; Risk; Route; Safety; Serotyping; Staging; T-Lymphocyte; Testing; Therapeutic; Transgenes; Viral; Viral Packaging; Virus; Work; adeno-associated viral vector; compare effectiveness; conventional therapy; gene correction; gene therapy; gene therapy clinical trial; high risk; improved; inhibitor/antagonist; neutralizing antibody; novel; pre-clinical; prevent; recombinant antihemophilic factor VIII; response; safety testing; success; transmission process; vector

DESCRIPTION (provided by applicant): This proposal sets the stage for clinical trials of gene therapy for hemophilia A. Here we concentrate on the use of adeno-associated viral (AAV) vectors with new capsid serotypes for liver directed gene therapy in a large animal model, namely, the hemophilia A dog. This work builds upon our previous success in "curing" the hemophilia A mouse using FVIII gene delivery in two new AAV serotypes, AAV8 and AAV9. Our studies in hemophilia A dogs, while more modestly successful, have also been encouraging with both new AAV serotypes. In this application, we evaluate further these AAV serotypes, beginning with delivery of FVIII cDNA in heavy chain and light chain vectors. We test responses at two different doses for both AAV8 and AAV9, and compare intraportal to intravenous routes of vector administration, We then go on to develop an effective, smaller single chain vector that can be produced in high titers, and test this single chain vector using the best combination of serotype, dose, and route of administration. We will also carry out therapy with our best conditions in young dogs, in an effort to initiate treatment before the onset of serious morbidity and also to prevent inhibitor formation to rFVIII used for conventional therapy. Lastly, we will determine whether FVIII can be readministered to dogs using a different serotype vector from the vector used in the original virus infusion. In all of these studies significant efforts will be made to test the safety of the new AAV vectors, concentrating on studies of neutralizing antibodies, development of transaminitis, and germline transmission of virus. At the end of these studies, we expect to have discovered treatment conditions that consistently produce long-term therapeutic levels of FVIII (>10% of normal) in a large animal, the hemophilia A dog. These results should make clinical trials with AAV vectors an appropriate next step.

描述（由申请人提供）：该提案为 A 型血友病基因治疗的临床试验奠定了基础。在这里，我们重点关注在大型动物模型（即 A 型血友病狗）中使用具有新衣壳血清型的腺相关病毒 (AAV) 载体进行肝脏定向基因治疗。这项工作建立在我们之前使用两种新 AAV 血清型 AAV8 和 AAV9 中的 FVIII 基因传递“治愈”A 型血友病小鼠的成功基础上。我们对 A 型血友病狗的研究虽然取得了一定的成功，但对于两种新的 AAV 血清型也令人鼓舞。在此应用中，我们从重链和轻链载体中递送 FVIII cDNA 开始，进一步评估这些 AAV 血清型。我们测试了 AAV8 和 AAV9 在两种不同剂量下的反应，并比较了门静脉内和静脉内的载体施用途径。然后，我们继续开发一种可以高滴度生产的有效、较小的单链载体，并使用血清型、剂量和施用途径的最佳组合来测试该单链载体。我们还将以最好的条件对幼犬进行治疗，努力在严重发病前开始治疗，并防止常规治疗中使用的 rFVIII 形成抑制剂。最后，我们将确定是否可以使用与原始病毒输注中使用的载体不同的血清型载体重新给狗注射 FVIII。在所有这些研究中，将做出重大努力来测试新 AAV 载体的安全性，重点是中和抗体、转氨炎的发展和病毒种系传播的研究。在这些研究结束时，我们期望发现能够在大型动物（A 型血友病狗）中持续产生长期治疗水平的 FVIII（> 正常值的 10%）的治疗条件。这些结果应该使 AAV 载体的临床试验成为适当的下一步。