被搁置了10年的埃博拉病毒疫苗大纲

GALVESTON, Texas — Almost a decade ago, scientists from Canada and the United States reported that they had created a vaccine that was 100 percent effective in protecting monkeys against the Ebola virus. The results were published in a respected journal, and health officials called them exciting. The researchers said tests in people might start within two years, and a product could potentially be ready for licensing by 2010 or 2011.

德克萨斯州加尔维斯顿——差不多10年前，加拿大和美国的科学家宣布，他们研制出了一种可以保护猴子不被埃博拉病毒感染的疫苗，百分之百有效。其研究成果被发表在了一本颇有声望的期刊上；卫生官员们曾表示，该成果令人兴奋。研究人员当时称，可能会在两年之内对疫苗进行人体测试；到2010年或者2011年，可能已经为疫苗产品获得许可做好了准备。

It never happened. The vaccine sat on a shelf. Only now is it undergoing the most basic safety tests in humans — with nearly 5,000 people dead from Ebola and an epidemic raging out of control in West Africa.

他们的话并未成真。该疫苗一度被束之高阁，直到现在才开始进行最基本的人体测试——此时，已有近5000人死于埃博拉，西非地区疫情肆虐，失去了控制。

Its development stalled in part because Ebola is rare, and until now, outbreaks had infected only a few hundred people at a time. But experts also acknowledge that the lack of follow-up on such a promising candidate reflects a broader failure to produce medicines and vaccines for diseases that afflict poor countries. Most drug companies have resisted spending the enormous sums needed to develop products useful mostly to countries with little ability to pay.

该疫苗的研发之所以被搁置，在某种程度上是因为埃博拉病毒非常罕见，而且以前每次爆发疫情，都只有数百人被感染。但业内人士也承认，没能对这一颇有前途的候选药品进行后续研究，映衬出了更大的失败：穷国的民众饱受某些疾病的折磨，但针对此类疾病的药物或疫苗却无法被生产出来。有些国家根本没钱买药，大部分制药公司都不愿投入大量资金去研制主要应用于这些国家的产品。

Now, as the growing epidemic devastates West Africa and is seen as a potential threat to other regions as well, governments and aid groups have begun to open their wallets. A flurry of research to test drugs and vaccines is underway, with studies starting for several candidates, including the vaccine produced nearly a decade ago.

眼下，由于不断升级的疫情让西非陷入了混乱，并被视为对其他区的潜在威胁，各国政府和援助团体终于打开了自己的钱包。一连串旨在测试药物和疫苗的研究正在进行之中，其研究对象包括一些候选药品，如近10年前就已经被制造出来的那种疫苗。

A federal official said in an interview on Thursday that two large studies involving thousands of patients were planned to begin soon in West Africa, and were expected to be described in detail on Friday by the World Health Organization.

一位联邦官员周四接受采访时说，按照计划，两项涉及数千名患者的大型研究很快就会在西非启动，世界卫生组织(World Health Organization)将于周五公布相关细节。

With no vaccines or proven drugs available, the stepped-up efforts are a desperate measure to stop a disease that has defied traditional means of containing it.

由于没有疫苗或者经过验证的药物可用，大力推进研究工作实际上是为了阻止这种疾病的蔓延而采取的非常手段——使用传统的治疗方式已经无法控制它了。

"There's never been a big market for Ebola vaccines," said Thomas W. Geisbert, an Ebola expert here at the University of Texas Medical Branch in Galveston, and one of the developers of the vaccine that worked so well in monkeys. "So big pharma, who are they going to sell it to?" Dr. Geisbert added: "It takes a crisis sometimes to get people talking. ‘O.K. We've got to do something here.' "

“埃博拉疫苗的市场需求一直不大，”德克萨斯大学加尔维斯顿医学分部(University of Texas Medical Branch in Galveston)的埃博拉病毒专家托马斯·W·盖斯伯特(Thomas W. Geisbert)说。他同时也是那种对猴子很有效的埃博拉疫苗的研发者之一。“如果大量生产，他们要卖给谁呢？”盖斯伯特补充说：“有时候只有危机来临，才能引发人们的讨论。‘好吧，我们得做点什么了。'”

Dr. James E. Crowe Jr., the director of a vaccine research center at Vanderbilt University, said that academic researchers who developed a prototype drug or vaccine that worked in animals often encountered a "biotech valley of death" in which no drug company will help them cross the finish line.

范德比尔特大学(Vanderbilt University)某疫苗研究中心的主任小詹姆斯·E·克劳金(James E. Crowe Jr)博士称，学术界的研究人员开发出一种对动物有效的原型药物或疫苗之后，常常会与“生物科技死亡谷”不期而遇，没有制药公司愿意帮助他们越过终点。

The Ebola vaccine on which Dr. Geisbert collaborated is made from another virus, V.S.V., for vesicular stomatitis virus, which causes a mouth disease in cattle but rarely infects people. It had already been used successfully in making other vaccines.

盖斯伯特博士参与研发的埃博拉疫苗是利用另一种病毒——水疱性口炎病毒(VSV)制成的，这种病毒导致牛群患上口部疾病，但很少感染人。该病毒已被成功用于制造其他疫苗。

The researchers altered V.S.V. by removing one of its genes — rendering the virus harmless — and inserting a gene from Ebola. The transplanted gene forces V.S.V. to sprout Ebola proteins on its surface. The proteins cannot cause illness, but they provoke an immune response that in monkeys, considered a good surrogate for humans, fought off the disease.

研究人员通过移除VSV的一个基因——使该病毒变得无害——并嵌入埃博拉病毒基因来改变VSV病毒。这种移植的基因迫使VSV在表面产生埃博拉病毒蛋白。这些蛋白不会导致疾病，但它们在猴子身上引发免疫反应，治愈这种疾病。猴子被认为是代替人类测试药品的好选择。

The vaccine was actually produced in Winnipeg by the Public Health Agency of Canada. The Canadian government patented it, and 800 to 1,000 vials of the vaccine were produced. In 2010, it licensed the vaccine, known as VSV-EBOV, to NewLink Genetics, in Ames, Iowa.

该疫苗实际上是由加拿大公共卫生署(Public Health Agency of Canada)在温尼伯研发的。加拿大政府拥有专利权，目前已经生产了800-1000剂疫苗。2010年，该政府为爱荷华州埃姆斯的纽琳基因公司(NewLink Genetics)发放VSV-EBOV疫苗许可。

The Canadian government donated the existing vials to the World Health Organization, and safety tests of the vaccine in healthy volunteers have already begun.

加拿大政府将现有的疫苗捐赠给世界卫生组织，现在已经开始在健康的志愿者身上进行疫苗安全测试。

NewLink's product is one of two leading vaccines being tested. The other, which uses a cold virus that infects chimpanzees, was developed by researchers at the National Institutes of Health and GlaxoSmithKline. The first tests of an earlier version of it, employing a different cold virus, began in 2003.

纽琳基因公司的产品是两种正在进行测试的主要疫苗之一。另一种疫苗是由美国国立卫生研究院(National Institutes of Health/NIH)和葛兰素史克公司(GlaxoSmithKline)的研究人员研发的，该疫苗使用了黑猩猩感冒病毒。相关人员从2003年开始首次对之前使用不同感冒病毒制成的疫苗进行测试。

Several other vaccine candidates, not as far along, are also in the pipeline and may be ready for safety testing next year. Once any drugs or treatments pass the safety tests they will be available for use in larger numbers of people, and health officials are grappling with whether they should be tested for efficacy in the traditional way, in which some people at risk are given placebos instead of the active drug.

其他几种候选疫苗的进展没有那么快，但正在研制中，或许已经准备好于明年接受安全测试。一旦有药物或治疗方法通过安全测试，它们将可以用于广大人群，卫生官员正在考虑是否应该通过传统方式对这些药物进行疗效测试——给一些可能被感染的人安慰剂，而不是活性药物。

Governments and the military became interested in making vaccines against Ebola and a related virus, Marburg, during the 1990s after a Soviet defector said the Russians had found a way to weaponize Marburg and load it into warheads. Concerns intensified in 2001 after the Sept. 11 terrorist attacks and anthrax mailings.

20世纪90年代，在苏联叛徒称俄罗斯人已经找到将马尔堡病毒制成武器并将它装入弹头的方法后，各国政府及军队开始对制作抗埃博拉病毒及相关病毒——马尔堡病毒的疫苗感兴趣。2001年，在9·11恐怖袭击事件及炭疽邮件事件发生之后，他们更加关注疫苗的制作。

"The National Institutes of Health came up with a program called Partnerships in Biodefense that partnered researchers like me with companies, usually small companies," Dr. Geisbert said.

盖斯伯特博士说，“国立卫生研究院推出了一个叫作生物防御合作(Partnerships in Biodefense)的计划，推动像我这样的研究人员与公司的合作，通常是些小公司。”

The government money led to major advances in the laboratory, Dr. Geisbert said, but was insufficient to cover the huge costs of human trials. Nor could the small companies that were involved in the early studies in animals afford to pay for human trials. No finished product came to market.

盖斯伯特博士表示，政府的资助促使该实验室取得重大进展，但这些资金不足以支付人体试验所需要的巨额费用。那些参与动物试验早期研究的小公司也无法支付人体试验的费用。目前还没有成品上市。

Dr. Geisbert moved on, working on treatments for Ebola and another version of the V.S.V. vaccine. For the vaccine work, his main collaborator has been Dr. Heinz Feldmann, the chief of virology at the Rocky Mountain Laboratories in Hamilton, Mont., part of the National Institute of Allergy and Infectious Diseases.

盖斯波特博士继续研究埃博拉的治疗方法，以及另一种VSV疫苗。在疫苗研制工作方面，他的主要合作伙伴是蒙大拿州哈密尔顿落基山实验室(Rocky Mountain Laboratories)的首席病毒专家海因茨·费尔德曼(Heinz Feldmann)。落基山实验室隶属于美国国家过敏及传染性疾病研究所(National Institute of Allergy and Infectious Diseases)。

The newer version of the vaccine uses a slightly different form of V.S.V., one that Dr. Geisbert said he thought might be less likely to cause side effects, and more likely to gain quick approval because it has already been used as the basis for an H.I.V. vaccine and is known to the Food and Drug Administration. But the new version, VesiculoVax, made by Profectus Biosciences in Baltimore, has not yet been tested in humans.

新版疫苗使用的VSV病毒稍有不同，盖斯波特博士称这种病毒引起副作用的可能性较小，可能很快就会获得批准，因为它已经被用于制造HIV疫苗，美国食品与药品管理局(Food and Drug Administration)已经了解这种病毒。但巴尔的摩启程生物科学公司(Profectus Biosciences)生产的新疫苗VesiculoVax还没有进行人体测试。

The V.S.V. products are live vaccines, with replicating viruses that may cause a reaction. It is not clear what level of side effects will be considered acceptable.

VSV疫苗是活疫苗，不断复制的病毒可能会引起反应。目前尚不清楚何种水平的副作用是被认为可以接受的。

Chills and nausea are possible, Dr. Geisbert said, but he added, "Who cares, if you survive Ebola?"

盖斯特博士表示，可能出现畏寒、恶心的反应，但他还表示，“如果能治愈埃博拉，谁还在乎这些？”