Ebola test negative for woman in hospital

Dr. Katrina Hedberg, state health officer, talks to a huddle of reporters after officials announced that a Liberian woman tested negative for Ebola. There have been no cases in Oregon but medical staff treated this potential case as a real one.

(Stephanie Yao Long/The Oregonian)

A drug developed by an Oregon State University scientist may be used to treat patients infected with the Ebola virus.

The drug, manufactured by Sarepta Therapeutics in Cambridge, Mass., had promising results in clinical trials on infected monkeys, curing between 60 to 80 percent. All of those in the control group who did not get the drug died, said Patrick Iversen, an OSU professor and lead scientist on the project.

The next step could involve trials in West Africa, where nearly 13,300 people have been infected and about 4,960 have died.

"If the epidemic lasts, I'm pretty sure we will use the drug (in Africa)," Iversen said.

The company is discussing with the Food and Drug Administration the possibility of using the drug, AVI-7537, if needed in an emergency in the United States.

The National Institutes of Health is meeting with drug companies, including Sarepta Therapeutics, on Tuesday to discuss setting up clinical trials in West Africa. The FDA has approved two vaccines for testing and there are two other Ebola treatment drugs in the works besides AVI-7537, Iversen said: ZMapp and TKM-Ebola.

Although the need for treatments like AVI-7537 is now urgent considering the epidemic in Sierra Leone, Guinea and Liberia, the drug is a decade old.

It all started with a pinprick at the U.S. Army Medical Research Institute of Infectious Diseases in Maryland in 2004. A scientist was administering the Ebola virus to a mouse when the rodent kicked and the syringe jabbed her finger instead.

Officials at the institute called Iversen, who had just given a talk about the company's RNA-based technology and the possibility of using it to fight aggressive viruses. Could his drug help?

The scientists at Sarepta, formerly AVI BioPharma, whipped into full gear, working around the clock and developed the drug in record time, Iversen said.

"We skipped over six years of work in four days," he said. "That exercise taught us that we could respond extraordinarily quickly."

The drug wasn't needed in the end. The researcher wasn't infected. So the drug's development shifted out of fast gear, with the Phase 1 clinical trials finishing about two years ago.

Iversen said the drug was given to about 36 people, with steadily ramped-up dosage to check for tolerance and safety. No one experienced side effects related to the drug, Iversen said.

"We went through five or six iterations," he said. "We wanted to make sure it's safe."

AVI-7537 works by interfering with the virus' ability to hammer the body's immune system. The drug targets one of Ebola's seven genes, which makes a protein that, in turn, blocks the body's immune response. Essentially, the drug puts a clamp on the cell so it can't make the protein, giving the body a chance to fight back.

"We're messing up the virus' ability to be successful," Iversen said.

The drug is given intravenously for about 30 minutes daily for two weeks. The company has enough on hand to treat 20 patients, and in two or three months could manufacture enough to treat about 250 more.

But producing tens of thousands of doses could take a year or more and would cost hundreds of millions of dollars.

The focus now is on Africa. Wellcome Trust, a health-focused foundation based in Britain, is working on preparing treatment centers for Ebola clinical trials. Sarepta is ready to participate, Iversen said.

Though the outbreak appears to be slowing, the virus is not likely to disappear. It first emerged in 1976, with an outbreak in Sudan and another in the Democratic Republic of Congo, or Zaire. The latest outbreak is the largest to date, but Iversen said it won't be the last.

"There will be more outbreaks of Ebola," Iversen said. "It's not a matter of if but a matter of when."

-- Lynne Terry