VO慢速英语2019--抗癌药物中的"导弹"

Drug Developers Take Aim at 'Guided-Missile' Cancer Drugs

Companies are testing a record 89 treatments on humans to fight cancer. These treatments combine antibodies from the body's natural defense¹ system with agents that fight cancer.

They are testing what they call antibody-drug conjugates², or ADCs.

Researchers describe ADCs as "guided missiles" in the fight against cancer. They are designed to target cancer cells and then release cytotoxins – substances that have a toxic³ or poisonous effect on the cells.

ADCs are up to 10,000 times as powerful as most chemotherapy treatments. They also reduce damage to healthy tissue.

Developing ADCs has been a major aim for the biotechnology industry for years. Many experimental ADCs, however, failed because of the difficulty of combining the right antibody with the right cancer-killing substance. Some ADCs were found to be too weak. Others were too harmful.

From 2000 to 2018, only five ADCs won official approval. Only one ADC, developed by drug maker⁴ Roche, has reached $1 billion in yearly sales. It was approved in 2013 to treat breast cancer. Studies showed the drug increased the chances of disease-free survival for some patients compared with the usual treatment.

In 2019, U.S. officials approved three ADCs, the most ever in a single year. One of them was the breast cancer drug Enhertu, developed by AstraZeneca and Daiichi Sankyo. It was shown to help patients who had failed numerous treatments.The drug helped them survive more than 16 months on average before their disease worsened.

Padcev, a bladder cancer drug, received approval in December. Research showed that 44% of patients who had failed immunotherapy showed improvement when they were tested after treatment. In some cases, patients showed no evidence of cancer. The drug is a product of two companies, Astellas and Seattle Genetics.

Another drug, Polivy, was approved in June to treat lymphoma. When combined with two other treatments, 40% of patients showed no sign of disease. Polivy is a product of the Swiss drug maker Roche.

New record

Reuters news agency says the biotechnology industry is growing hopeful about the effectiveness of ADCs.

Information provided by Beacon⁵ Targeted Therapies shows that the number of ADC drug candidates is at record levels. Many more ADCs are being considered before human testing is permitted.

Beacon advises drug makers⁶ on targeted treatments. The service helps them decide whether to continue working on possible drugs or redirect efforts.

Current ADC projects include GlaxoSmithKline testing a drug to fight multiple myeloma.

ADC Therapeutics has launched several studies on experimental drugs for treating blood cancers and solid tumors.

And ImmunoGen, based in the American state of Massachusetts, is developing an ADC to treat ovarian cancer. In December, the U.S. Food and Drug Administration said the drug might become a candidate for a faster than normal approval.

The increase in ADC investment is partly because of improvements in what researchers are calling "linker" technology. The linker joins the antibody to the cancer-killing cytotoxins.

Giuseppe Curigliano is clinical director of early drug development at the European Institute of Oncology in Milan. He told Reuters, "There is a revival⁷ again because there is a new generation of molecules⁸ in which the linker is more efficient."

Words in This Story

chemotherapy – n. the use of chemical agents to treat disease

immunotherapy – n. treatment or prevention of disease that involved suppression or strengthening the body's natural defenses against disease

1 defense   

n.防御，保卫；[pl.]防务工事；辩护，答辩

参考例句：

• The accused has the right to defense.被告人有权获得辩护。
• The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。

2 conjugates   

v.列出（动词的）变化形式( conjugate的第三人称单数 )；结合，联合，熔化

参考例句：

• In English\"to have \" conjugates irregularly. 英语中“to have”变化不规则。 来自《现代英汉综合大词典》
• Conjugates of proteins with carbohydrate are termed glycoproteins. 蛋白质和碳水化合物的结合物称为糖蛋白。 来自辞典例句

3 toxic   

adj.有毒的，因中毒引起的

参考例句：

• The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
• There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。

4 maker   

n.制造者，制造商

参考例句：

• He is a trouble maker，You must be distant with him.他是个捣蛋鬼，你不要跟他在一起。
• A cabinet maker must be a master craftsman.家具木工必须是技艺高超的手艺人。

5 beacon   

n.烽火，（警告用的）闪火灯，灯塔

参考例句：

• The blink of beacon could be seen for miles.灯塔的光亮在数英里之外都能看见。
• The only light over the deep black sea was the blink shone from the beacon.黑黢黢的海面上唯一的光明就只有灯塔上闪现的亮光了。

6 makers   

n.制造者，制造商（maker的复数形式）

参考例句：

• The makers of the product assured us that there had been no sacrifice of quality. 这一产品的制造商向我们保证说他们没有牺牲质量。
• The makers are about to launch out a new product. 制造商们马上要生产一种新产品。 来自《简明英汉词典》

7 revival   

n.复兴，复苏，（精力、活力等的）重振

参考例句：

• The period saw a great revival in the wine trade.这一时期葡萄酒业出现了很大的复苏。
• He claimed the housing market was showing signs of a revival.他指出房地产市场正出现复苏的迹象。

8 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。