With hundreds of patients in Africa suffering the devastating effects of Ebola, health experts are scrambling to determine which drugs might offer the best experimental treatment, and researchers are being pressed by government officials to speed up their work.
Three treatments have shown especially promising results in monkeys, the researchers said. One, produced by tiny California biotech Mapp Biopharmaceutical, gained international prominence last week when it was given to two US aid workers who contracted Ebola in West Africa and have since shown signs of improvement.
Others are from Vancouver-based Tekmira Pharmaceuticals and privately-held Profectus BioSciences, of Tarrytown, NY.
The World Health Organisation said it would discuss this week the ethics of using Ebola drugs that have never been cleared for human use, wary of a long history of medicines being tested on people who were never properly informed of the risks. In the countries hardest hit by Ebola, suspicion of foreign medical workers is already widespread.
But the Health Minister of Nigeria, Onyenbuchi Chukwu, told reporters that he had asked US health officials about access to experimental Ebola therapies. US drugmakers are fielding questions from government officials about their ability to supply treatments in sufficient quantities should the request come.
“For years we’ve told the government you need to invest a little bit of money in this,” said Profectus chief scientific officer John Eldridge. “And now it’s, ‘Oh my God, how fast can you make this?’”
Officials at Mapp and Tekmira would not comment on efforts to make their treatments available in response to the outbreak.
Speaking at a news conference, US President Barack Obama said he lacks enough information to green-light Mapp’s drug to treat the deadly Ebola virus and that the initial response should focus on public health measures to contain the outbreak.
“We’ve got to let the science guide us, and I don’t think all the information is in on whether this drug is helpful,” the president said, adding that public health officials, in the course of containing the current outbreak, could assess whether new drugs or treatments can be effective.
“We’re focusing on the public health approach right now, but I will continue to seek information about what we’re learning about these drugs going forward,” he said.
James Crowe, director of the Vaccine Centre at Vanderbilt University who has been developing an Ebola treatment similar to Mapp’s, said a Pentagon agency contacted him last week about his work and added he will meet this week with government scientists about accelerating his research.
No Ebola drugs or vaccines have even entered mid-stage human trials, let alone been approved. The furthest along have been tested only in monkeys and a handful of humans.
Mapp Biopharmaceutical began developing its ZMapp treatment more than a decade ago. It consists of a cocktail of monoclonal antibodies, proteins that are highly specific for the Ebola virus and that are produced in bioengineered tobacco plants.
Last year, ZMapp passed a stiffer test: monkeys that had been infected with Ebola and developed fevers and other symptoms received the intravenous cocktail 104 to 120 hours after infection; 43 per cent recovered.
When the US government decided to develop a contingency plan in case of accidental exposure to Ebola by one or two people at a US research facility, it began storing a small amount of ZMapp, according to a source familiar with the contingency plan. ZMapp was chosen because the science is relatively easy to understand and the risks considered relatively small, the source said.
The stock of Tekmira soared on expectations its Ebola drug might speed toward approval due to the crisis, or even be used in the current outbreak.
Under a $140 million contract with the US Department of Defence, it is developing a drug based on a genetic technology called RNA interference.