FDA-approved medications may have unexpected use: Stopping deadly ebola

by Josh Barney

A class of drugs that includes treatments for breast cancer and infertility appears able to inhibit the deadly, incurable Ebola virus, new research suggests.

As part of a collaborative effort, researchers at the University of Virginia School of Medicine have shown that the drugs clomiphene, which is used to treat , and toremifene, used to treat , can effectively block infections in mice. The drugs, and others with similar structures, appear to prevent the virus from delivering its RNA into the cytoplasm of cells. Without the ability to deliver its genetic payload, the virus degrades quickly and is removed from the body.

"These are among the first FDA-approved compounds shown to be effective against Ebola in mouse models," U.Va. researcher Judith M. White said. "With a virus this lethal, you want something to combat it."

Ebola infections carry of up to 90 percent. It strikes both humans and other primates, and there are fears it could be used as a . There's no cure, so it's imperative that scientists find effective treatments. The eventually could lead to the repurposing of FDA-approved drugs, already available for prescription, to combat the virus.

The findings are the result of an innovative partnership of academia, government and private industry. The drugs' potential use against Ebola was first identified by investigators at biopharmaceutical company Zalicus and the U.S. Army Medical Research Institute of Infectious Diseases; they then turned to U.Va. for its expertise in figuring out how the drugs worked against the virus. U.Va. has developed an important assay that lets researchers analyze each step of the cellular infection process, allowing them to determine how the two drugs – and potentially other, similar drugs – undercut Ebola.

The U.Va. researchers concluded that the drugs were preventing the virus from fusing with membranes in targeted cells, essentially hemming in the .

" is in a race against the clock when it gets into the cell," said Jason Shoemaker, a postdoctoral fellow who developed the assay as a graduate student in White's lab. "We want to lock the door on it."

The research could have important ramifications for understanding the Ebola infection process. "There is a lot about Ebola viruses that is very strange compared to other viruses," Shoemaker said. "Any work that helps uncover more information about the viral entry pathway is helpful."

The U.Va. research posed no health risk, as the researchers used what are known as "virus-like particles" that contain no genetic material.

In evaluating the drugs' potential for stopping Ebola, U.Va. worked closely with both Zalicus and the Army Medical Research Institute, which handled the work involving live viruses.

White noted the unconventional process that led to the discovery of the drugs' anti-Ebola properties. Instead of attempting to develop a drug starting at the molecular level, Zalicus began by looking for existing drugs that could inhibit Ebola.

"This whole approach is the reverse of how a molecular biologist might approach the problem," White said. "If we'd gone with the molecular approach, we would never have looked at this class of drugs."

The findings have been published online by the journal Science Translational Medicine. The U.Va. researchers plan to continue their collaborative efforts and will look for drugs that may be even better at battling Ebola than and toremifene.

"Our findings suggest we are not talking about one specific drug," Shoemaker said. "It's a whole family. One might be better."

Related Stories

Cancer drugs could halt Ebola virus

Feb 29, 2012

Some cancer drugs used to treat patients with leukemia may also help stop the Ebola virus and give the body time to control the infection before it turns deadly, US researchers said on Wednesday.

Ebola's secret weapon revealed

May 02, 2013

Researchers have discovered the mechanism behind one of the Ebola virus' most dangerous attributes: its ability to disarm the adaptive immune system.

Recommended for you

Where Ebola battles are won

3 hours ago

(HealthDay)—Four hospitals that are home to advanced biocontainment facilities have become America's ground zero in the treatment of Ebola patients.

Depression tied to worse lumbar spine surgery outcomes

6 hours ago

(HealthDay)—Depressive symptoms are associated with poorer long-term outcome in patients undergoing surgery for lumbar spinal stenosis (LSS), according to research published in the Oct. 1 issue of The Sp ...

Ebola death toll edging to 4,900 mark: WHO

6 hours ago

The death toll in the world's worst-ever Ebola outbreak has edged closer to 4,900, while almost 10,000 people have now been infected, new figures from the World Health Organization showed Wednesday.

US to track everyone coming from Ebola nations

7 hours ago

U.S. authorities said Wednesday that everyone traveling into the U.S. from Ebola-stricken nations will be monitored for symptoms for 21 days. That includes returning American aid workers, federal health employees ...

User comments