已经有越来越多的资料支持使用血管靶向药物(vascular targeting agents, VTAs),这种药物被设计用来寻找并通过阻断肿瘤血供来摧毁癌组织内的血管生成。
血管靶向药物的作用机制不同于广为人知的血管生成抑制剂(angiogenesis inhibitors),血管生成抑制剂通过切断新血管的形成来减缓肿瘤生长。美国德克萨斯州西南医疗中心(Dallas,TX,USA)的Jin He博士最近在他的研究中报道说:放射治疗能够显著增加一种被命名为3G4的Tarvacin等价物的抗肿瘤活性。Tarvacin是由Peregrine制药公司(Peregrine Pharmaceuticals,Tustin,CA,USA)研制成功的血管靶向药物。使用3G4联合外源性辐射治疗实验动物,结果肿瘤生长速度下降了98%,而单独使用放射治疗或者3G4治疗分别是85%和67%。
2004年11月在美国剑桥(Cambridge,MA,USA)举行的血管靶向药物会议的展示会上,Peregrine制药公司的Philip Thorpe博士评论说:“血管靶向药物正从临床前研究阶段进展到了临床试验阶段。这次会议很特别,因为会议聚集了各领域的专家。这样我们可以亲自讨论研究项目、互相学习、产生新的理念、并将这些新理念融会贯通,然后带回实验室,并最终进入临床应用。”
Peregrine制药公司致力于研究癌症治疗与诊断药物,包括血管靶向药物、抗血管生成药物、促进血管渗透性药物(vasopermeation enhancement agents, VEAs)。该公司与美国食品药品管理局(FDA)紧密合作,开展了首次Tarvacin临床试验。Tarvacin是一种抗体,结合于磷脂酰丝氨酸磷脂,直接结合于肿瘤血管从而抑制肿瘤的生长形成。
Vascular Targeting Reduces Tumor Growth by 98%
A growing body of practical data su orts the use of vascular targeting agents (VTAs), which are designed to seek and destroy preexisting blood ve els within cancerous tumors by blocking off the tumor’s blood su ly.
VTAs represent a therapeutic a roach that is different from the more widely known angiogenesis inhibitors, which slow tumor growth by cutting off new blood ve el formation. Dr. Jin He, from the University of Texas Southwestern Medical Center (Dallas, TX, USA) has recently reported in his studies that radiation therapy had significantly increased the antitumor activity of a Tarvacin equivalent named 3G4. Tarvacin is a VTA developed by Peregrine Pharmaceuticals (Tustin, CA, USA;). In lab animals treated with 3G4 plus external beam radiation, tumor growth was reduced by 98% as compared with 85% for radiation therapy alone or 67% with 3G4 alone.
At a presentation at the Vascular Targeting Agents conference in Cambridge (MA, USA) in November 2004, Philip Thorpe, Ph.D., a member of Peregrine Pharmaceuticals remarked, “VTAs are progre ing through preclinical development and into clinical trials. This conference is unique in that it brings together experts in all of the various a roaches--we can discu the research in person, learn from each other and take new ideas coming out of that mix back to the lab, and ultimately, to the clinic.”
Peregrine Pharmaceuticals develo cancer therapeutics and diagnostics including VTAs, and anti-angiogenesis and vasopermeation enhancement agents (VEAs). The company is working closely with the U.S. Food and Drug Administration (FDA) to start its first clinical trial using Tarvacin. Tarvacin is an antibody that binds to the pho holipid pho hatidylserine, which binds directly to tumor blood ve els to inhibit tumor growth and development.