Antiviral compound protects nonhuman primates against Ebola virus

Scientists protected 75 percent of rhesus monkeys infected with Ebola virus that were treated with a compound targeting the expression of VP24, a single Ebola virus protein--suggesting that VP24 may hold the key to developing effective therapies for the deadly disease.

The study, which appears in today's edition of mBio, the online journal of the American Society for Microbiology, was conducted by the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) in collaboration with biotechnology firm Sarepta Therapeutics, Inc.

For over a decade, USAMRIID and Sarepta have been collaborating to develop and test a class of antisense compounds known as phosphorodiamidate morpholino oligomers (or PMOs), according to principal investigator and first author Travis K. Warren, Ph.D., of USAMRIID.

"Antisense drugs are designed to enter cells and eliminate viruses by preventing their replication," Warren said.

The drugs act by blocking the translation of critical viral genetic sequences, preventing the protein from being made and giving the infected host time to mount an immune response and clear the virus, he explained.

In work previously published in the journal Nature Medicine, the team demonstrated that a combination PMO called AVI-6002 - a product targeting genes that code for two proteins, VP24 and VP35 - prevented Ebola virus infection in rhesus monkeys. The current study compared the activity of the individual components against that of the combination treatment. In this experiment, animals were treated with AVI-7537, which targets VP24 alone; AVI-7539, which targets VP35 alone; or AVI-6002, which targets both proteins. A fourth group served as the untreated control. Animals were treated once a day for up to 14 days beginning approximately one hour after virus exposure.

How do I protect myself against Ebola? If you must travel to an area affected by the 2014 Ebola outbreak: Wash your hands frequently or use an alcohol-based hand sanitizer. Avoid contact with the blood and body fluids of any person, particularly someone who is sick. Do not handle items that may have come in contact with an infected person’s blood or body fluids. Do not touch the body of someone who has died from Ebola. Do not touch bats and nonhuman primates (apes and monkeys) or their blood and fluids and do not touch or eat raw meat prepared from these animals. Avoid facilities in West Africa where Ebola patients are being treated. The U.S. Embassy or consulate is often able to provide advice on healthcare facilities that are suitable for your medical needs. Report any potential unprotected Ebola exposure or illness promptly. Seek medical care immediately if you develop fever, fatigue, headache, muscle pain, diarrhea, vomiting, stomach pain, or unexplained bruising or bleeding. Limit your contact with other people until and when you travel to the doctor. Do not travel anywhere else.