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Talimogene laherparepvec (''tal im' oh jeen la her" pa rep' vek''), often simply called "T-VEC" is a cancer-killing (oncolytic) virus studied for the treatment of melanoma and other advanced cancers. The drug was developed by BioVex, Inc. under the name OncoVEXGM-CSF. It was acquired by Amgen in 2011.〔Bloomberg News. (2011, January 24). Amgen buys a cancer drug maker. ''New York Times''. Retrieved from http://www.nytimes.com. Available (here )〕 With the announcement of positive results in March 2013, T-VEC became the first oncolytic virus to be proven effective in a Phase III clinical trial.〔 In October 2015, the US Food and Drug Administration approved the injectable formulation of T-VEC, with the brand name Imlygic, for the treatment of melanoma in patients with inoperable tumors.〔(【引用サイトリンク】title=FDA approves Amgen's Injected Immunotherapy for Melanoma )〕 ==Mechanism of action== T-VEC was engineered from herpes simplex virus 1 (HSV-1), a relatively innocuous virus that normally causes cold sores. A number of genetic modifications were made to: * Attenuate the virus (so it could no longer cause herpes) * Increase selectivity for cancer cells (so it destroys cancer cells while leaving healthy cells unharmed) * Secrete the cytokine GM-CSF (a protein naturally secreted in the body to initiate an immune response) T-VEC has a dual mechanism of action, destroying cancer both by directly attacking cancer cells and also by helping the immune system to recognize and destroy cancer cells. T-VEC is injected directly into the patient’s tumors. The virus invades both cancerous and healthy cells, but it is unable to replicate in healthy cells and thus they remain unaffected. Inside a cancer cell, the virus is able to replicate, secreting GM-CSF in the process. Eventually overwhelmed, the cancer cell lyses (ruptures), destroying the cell and releasing new viruses, GM-CSF, and an array of tumor-specific antigens (pieces of the cancer cell that are small enough to be recognized by the immune system).〔 The GM-CSF attracts dendritic cells to the site. Dendritic cells are immune cells that process and present antigens to the immune system so that the immune system can then identify and destroy whatever produced the antigen. The dendritic cells pick up the tumor antigens, process them, and then present them on their surface to cytotoxic (killer) T cells. Now the T cells are essentially "programmed" to recognize the cancer as a threat. These T cells lead an immune response that seeks and destroys cancer cells throughout the body (e.g., tumors and cancer cells that were not directly injected with T-VEC).〔〔Kaufman HL, Kim DW, DeRaffele G, Mitcham J, Coffin RS, Kim-Schulze S. Local and distant immunity induced by intralesional vaccination with an oncolytic herpes virus encoding GM-CSF in patients with stage IIIc and IV melanoma. ''Ann Surg Oncol''. 2010;17(3):718-30. Available (here )〕 In this way, T-VEC has both a direct effect on injected tumors and a systemic effect throughout the entire body.〔Núñez MA. Tumor killer viruses. ''Mapping Ignorance''. January 9, 2013. Available (here )〕 Because the adaptive immune system "remembers" a target once it has been identified, the effect of an oncolytic virus like T-VEC may be durable (e.g., prevent relapse). For this reason T-VEC is injected into just enough tumors to start the immune process. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「talimogene laherparepvec」の詳細全文を読む スポンサード リンク
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