基因君官网
2015年4月2日讯 /生物谷BIOON/ –随着生物技术的发展，科学家们相继开发出越来越多的新方法对抗肿瘤。除了近年来火爆到不能再火爆的肿瘤免疫疗法外，肿瘤基因治疗也已经为越来越多的科学家所认同。
不过，由于这种疗法会直接作用于患者体内的遗传物质，不少研究人员仍然对这一疗法持审慎的态度。同时以过去几年肿瘤基因疗法的经验来看，这种方法相比于免疫疗法等来说的确还存在这样或那样的问题。因此，最近几年鲜有重量级的肿瘤基因疗法研究见诸报道。
不过，最近来自休斯顿的生物医药公司MultiVir决定继续向前迈出一大步。公司已经正式向证券交易委员会提交了一份总额达7000万美元的IPO计划用于支持公司开发的病毒载体技术进入临床二期阶段。此次，MultiVir计划推出用于治疗结肠癌和头颈癌的腺病毒载体治疗方案。如果一切顺利，MultiVir有望成为首个获得FDA批准上市的基因疗法。
而MultiVir公司也在相关申请材料中着重介绍了公司目前正在进行的两种基因疗法的研究特点。首先，为了打消市场的疑虑，公司开发的这两种腺病毒重组载体将不会整合宿主细胞DNA，以降低出现副作用的风险。公司强调，肿瘤的基因疗法副作用并不会超过现有的化疗、放疗以及免疫疗法。目前公司文件中提及的药物副作用包括过敏、疲劳、发烧等症状。
此外，公司还将结合不同的药物输送系统将重组病毒载体输入病灶部位。研究人员将采用静脉内注射的方式输送治疗结肠癌的腺病毒载体药物Ad-p53，而采用瘤内注射的方式输送治疗头颈瘤的药物Ad-IL-24。
不过，有意思的是，在这份报告中MultiVir公司还特别提到了中国的赛百诺基因公司。MultiVir声称赛百诺公司销售的一种基因疗法与Ad-p53类似并侵犯了MultiVir的一些专利。（生物谷Bioon.com）
详细英文报道：
Houston’s MultiVir, a developer of viral vectors to deliver anticancer gene therapy, just filed for a $70 million IPO with the Securities and Exchange Commission as it seeks funding for clinical trials of its Phase I/II lead candidates for colorectal cancer and head and neck cancer, and to take the first FDA-approved gene therapy to the market.
Both candidates utilize adenovirus as their specific vector. It does not typically integrate into the host cell’s DNA, reducing the risk of side effects and disruptions to normal gene function. Other MultiVir candidates use a herpes simplex and vaccinia virus platform.
The two lead candidates have completed Phase I. The company plans to advance them into Phase I/II trials, where they will be tested as combination therapies. “The side effects of viral gene therapies do not typically overlap with those of commonly used cancer treatments such as chemotherapy, radiation and monoclonal-antibody immunotherapy, which we believe will permit combination treatments with existing therapies,” the filing says. The side effects of viral vectors can include allergic reactions, fever, fatigue, nausea and low blood pressure, according to the filing.
The products will be developed in combination with drug delivery devices, like a pump or injection system, MultiVir says. For optimal bioavailability, the colorectal cancer candidate (Ad-p53) will use intra-arterial delivery, while the head and neck cancer candidate (Ad-IL-24) will utilize intratumoral administration because the gene therapy being employed secretes a protein, according to the filing. Both techniques require a high level of surgical technique and precision.
China’s SiBiono GeneTech is selling an adenovirus drug similar to p53 in that country. MultiVir says SiBiono is violating some of its patents, but says the drug is not available in the U.S. or Europe, where the Chinese company has yet to file for approval.
MultiVir reported a loss of $2.9 million in 2014, up from $1 million in 2013. R&D expenditure more than doubled during that time period to $1.67 million in 2014. A $70 million IPO would allow it to keep investing in drug delivery and biological research at a significantly high rate, in the hopes of a payoff down the road for patients and Wall Street investors.