Federal health officials plan to start testing vaccines against Ebola in Liberia in the coming weeks, to be followed by trials in Sierra Leone, as well. And they hope to begin testing soon some of the most promising treatments for Ebola, including a drug grown in tobacco plants.
The vaccine trials will be the first to involve people at highest risk for catching Ebola – health care workers, family members and burial teams in countries at the epicenter of the epidemic. And they are an example of an unprecedented acceleration of research to battle a disease in real time.
“A safe and effective vaccine will undoubtedly be a critical tool,” Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, told reporters. NIAID, one of the National Institutes of Health, is helping sponsor the first vaccine trial, about to kick off in Liberia.
Ebola has infected more than 21,000 people in Liberia, Sierra Leone and Guinea, and it’s killed 8,600 of them. The spread has begun to slow, but only a little, and the World Health Organization doesn’t project an end to the epidemic before the middle of the year, and only then with a sustained effort.
“A safe and effective vaccine will undoubtedly be a critical tool."
There hasn’t been a vaccine to prevent it and there’s no specific treatment. That wasn’t a big issue in years before, because outbreaks were always limited and kept to, at most, a few hundred people. Research had started on treatments and vaccines, but slowly, with only a trickle of funding as larger sums of money went to more pressing threats.
Now that Ebola has caused a giant epidemic, one that’s spread to the U.S. and Europe, that has focused both attention and efforts.
The first vaccine trial, set to start within the coming weeks, will pit two different vaccines against one another and against a placebo. As many as 27,000 people will be enrolled to try either GlaxoSmithKline’s vaccine, one made by NewLink Genetics and the Canadian government and licensed by Merck, or a shot of saline as the placebo.
Both the vaccines use harmless viruses to carry little pieces of Ebola into the body. Merck’s uses a virus called vesicular stomatitis virus or VSV; Glaxo’s uses a common cold virus called an adenovirus that affects chimpanzees but not people. Animal studies show they should stimulate an immune response that would protect against infection and early tests in human volunteers show they are safe.
“The next step is to determine efficacy in both vaccines as well as further safety,” Fauci said. Usually, this is a process that takes years. The federal government and the companies it’s working with have condensed this into a few weeks, with unprecedented cooperation from the governments of Liberia and Sierra Leone to get the trials going.
Two other vaccines are in earlier stages of development – one made by a company called Profectus and another by Johnson & Johnson.
At the same time, the Health and Human Services Department is pushing the development of drugs to treat Ebola – especially one called ZMapp that hit the headlines when it was used to treat the first U.S. Ebola patient, Dr. Kent Brantly.
Made by a tiny company called Mapp Biopharmaceuticals, ZMapp consists of three lab-engineered immune system proteins called monoclonal antibodies. They are carefully designed to precisely attack Ebola. ZMapp’s are grown in tobacco plants in a process that makes a nice product but that is painfully slow. It’s so slow that right now there is hardly any ZMapp at all.
"We wanted to expand our ability to make more of the tobacco-based plant product."
HHS is trying to speed that up and has been on a search for other companies that can make the monoclonal antibodies. Kentucky BioProcessing, which grows the antibodies in a close relative of the tobacco plant, could only produce a few dozen doses a month. Robin Robinson, director of the Biomedical Advanced Research and Development Authority at HHS, says a team of experts has helped the company more than double that yield.
"We wanted to expand our ability to make more of the tobacco-based plant product," Robinson told NBC News.
Now they’re in negotiations with two other companies – a small biotech called Medicago and another called Caliber Biotherapeutics.
And larger companies such as Amgen, Regeneron and Genentech are trying to make the ZMapp antibodies in Chinese hamster ovary cells. Mapp would get royalties from any such products, Robinson said.
In one of the trials being planned for Liberia, ZMapp will be tested against convalescent plasma – a fluid made from the blood of people who have survived Ebola.