溶瘤病毒（不管是自然的还是人工设计的）喜欢感染和溶解肿瘤细胞。David Kirn及其同事报告了一个第一阶段的临床试验，通过该试验，他们演示了在只有一次注射之后，系统便能够将人工设计的溶瘤病毒JX-594选择性输送到肿瘤组织。
肿瘤活体检查结果表明，这种病毒能在癌症中复制，但不能在相邻正常组织中复制。
JX-594是设计用来在能够容留表皮生长因子受体/Ras通道的激发的一系列癌症细胞中来复制的。
虽然该临床试验并不是设计用来演示临床效果，但其结果却表明，JX-594在一些患者身上也许能引起临床反应。
生物探索推荐英文摘要
Intravenous delivery of a multi-mechanistic cancer-targeted oncolytic poxvirus in humans
The efficacy and safety of biological molecules in cancer therapy, such as peptides and small interfering RNAs (siRNAs), could be markedly increased if high concentrations could be achieved and amplified selectively in tumour tissues versus normal tissues after intravenous administration. This has not been achievable so far in humans. We hypothesized that a poxvirus, which evolved for blood-borne systemic spread in mammals, could be engineered for cancer-selective replication and used as a vehicle for the intravenous delivery and expression of transgenes in tumours. JX-594 is an oncolytic poxvirus engineered for replication, transgene expression and amplification in cancer cells harbouring activation of the epidermal growth factor receptor (EGFR)/Ras pathway, followed by cell lysis and anticancer immunity1. Here we show in a clinical trial that JX-594 selectively infects, replicates and expresses transgene products in cancer tissue after intravenous infusion, in a dose-related fashion. Normal tissues were not affected clinically. This platform technology opens up the possibility of multifunctional products that selectively express high concentrations of several complementary therapeutic and imaging molecules in metastatic solid tumours in humans.
