VOA常速英语:“天下无癌”不再是梦？

Scientists at Pfizer, a pharmaceutical giant and AbbVie Stemcentrx, a small biotech firmhave developed a new drug that targets a number of aggressive types of cancer.These cancers are difficult to treat, and often reoccur.

The drug these companies have developed works in mice and in monkeys, and human trial is underway.

We’re hoping to rip out the cancer by its roots, essentially.Like when you’re weeding a garden, you need to get the roots so that the weed doesn’t grow back,and the way we’ve designed this drugis to go after the roots of the tumor and we deliver this chemotherapy that essentially kills those cells."Mark Damelin spoke by Skype from Pfizer’s research center in New York.

The drug has a two-pronged approach —— it’s an antibody that helps fight off the cancer.Scientists have attached the chemotherapy drug to the antibody which is a protein molecule.The antibody attaches to a developing cancer cell to prevent it from growing, while the chemotherapy kills it.

“This therapy is, essentially, a guided missile.”

Damelin says close to 30 percent of patients with ovarian cancer in the trial are showing a positive response.These are patients for whom every other therapy has failed.

The hope is that this new drug could replace standard chemotherapy.And because it is so targeted, it would be much less toxic and have fewer side effects.If it works, the scientists say it might also help patients with other kinds of cancers including cancers of the prostate,stomach, esophagus and an aggressive type of leukemia.

A larger human trial is set to begin this year.If it succeeds, this drug could save the lives of people with these hard to treat cancers.

Carol Pearson, VOA news, Washington.