Racing against the epidemic
Too little and too late
Manufacturers of antibodies and vaccines have already lost the race against the Ebola virus epidemicArtem Kosmarsky, <url>
Attempts to contain the spread of the disease by isolating patients and tracing their social connections have failed. Now the world community is pinning all hope on biomedical means: monoclonal antibodies and vaccines. However, Ebola drug manufacturers have already lost the race – the epidemic is spreading too fast for biotech and pharmaceutical firms to keep up with it. The main problem, according to Western researchers, is fatally limited production capacity.
From the point of view of science, the production of an Ebola vaccine is not something super complicated. Pharmaceutical companies have experience in the production of similar drugs, and animal tests have shown that it is quite easy to defeat the virus by correcting the immune response. "Although the fever itself is destructive to the body (we are talking primarily about hemorrhagic syndrome), a small amount of neutralizing antibodies is enough to protect against it," says John Eldridge, chief researcher at Profectus BioSciences, which is also preparing an Ebola vaccine, but has received almost no funding so far. The main difficulties are connected with mass production.
The best situation is with the vaccine, which was developed by American scientists and produced by the British corporation GlaxoSmithKline (GSK): since the second of September, it has been undergoing human trials. GSK has promised to issue up to ten thousand doses of the vaccine (it consists of the surface protein of the Ebola virus, "sewn" into the weakened adenovirus of chimpanzees) by the end of the year. But such a volume will not stop the epidemic: hundreds of thousands of doses are needed, and with the existing production scale, they will be available only in a year and a half. The company is considering expansion, but it should be guaranteed a market for the vaccine. "When we contacted the World Health Organization in March, when the first cases of infection became known, no one showed interest. We were answered: "Thank you, we will call you back," says Ripley Ballou, the program manager.
Another vaccine, which the world scientific community considers more effective, has also begun clinical trials on humans. It was developed by employees of the Canadian National Microbiological Laboratory, and the production (under license) was entrusted to a small biotechnology company NewLink Genetics (Ames, Iowa). The drug consists of an altered vesicular stomatitis virus (infecting cattle), where the Ebola surface protein gene is inserted. The company can present only 1,500 doses. Profectus BioSciences is also preparing its vaccine, but to increase production from five to twenty thousand doses, the company also needs a guaranteed source of funding.
In principle, it is very simple to produce vaccines: you need to grow more of the original vaccine viruses (the so-called production strain), collect them and process them. Okairos, a small Italian company that manufactures a vaccine for GSK, grows the virus in a cell line contained in disposable bioreactors with a capacity of up to 200 liters. It will take about two months to create the claimed ten thousand doses.
The founder of Okairos, Riccardo Cortese, said that ten million dollars would be enough to re-equip the complex: the company could process several four-hundred-liter bioreactors in just two months. With such a scale of production, the company could produce 100 thousand doses per month.
But Ballou is more cautious in his assessments. First of all, there is already a shortage of the original vaccine viruses: "there were not so many test tubes, and we are already running out of our stocks." Secondly, the optimal environment for production is giant bioreactors with a capacity of more than a thousand liters, similar to tanks for transporting beer. The problem is that it is very difficult to "hurry up" cell lines: the rate of cell growth is biologically determined. In the best case, Ballou claims, hundreds of thousands of doses will be ready only in nine months, and it will cost at least $ 25 million.
In principle, it is very simple to produce vaccines: you need to grow more of the original vaccine viruses (the so-called production strain), collect them and process them. Okairos, a small Italian company that manufactures a vaccine for GSK, grows the virus in a cell line contained in disposable bioreactors with a capacity of up to 200 liters. It will take about two months to create the claimed ten thousand doses.
The founder of Okairos, Riccardo Cortese, said that ten million dollars would be enough to re-equip the complex: the company could process several four-hundred-liter bioreactors in just two months. With such a scale of production, the company could produce 100 thousand doses per month.
But Ballou is more cautious in his assessments. First of all, there is already a shortage of the original vaccine viruses: "there were not so many test tubes, and we are already running out of our stocks." Secondly, the optimal environment for production is giant bioreactors with a capacity of more than a thousand liters, similar to tanks for transporting beer. The problem is that it is very difficult to "hurry up" cell lines: the rate of cell growth is biologically determined. In the best case, Ballou claims, hundreds of thousands of doses will be ready only in nine months, and it will cost at least $ 25 million.
Currently, a bill is under consideration in the US Congress that will provide the US Ministry of Health with $ 58 million for the development of vaccines and drugs against Ebola. The International Monetary Fund (IMF) can also allocate $127 million to West African countries. This will help in the fight against the epidemic, but revolutionary results should not be expected. "I do not know if these countermeasures will arrive in time and whether we will be able to stop the process. But I hope that by the time the next epidemic breaks out, the necessary actions will be taken and what we see now will never happen again," the representative of the ministry said.
Even if the production of vaccines can be increased tenfold, in the foreseeable future it will not be enough for countries where the epidemic is already raging. There is a chance that Ebola fever will not be allowed to enter the "clean" neighboring territories – thanks to vaccination in the form of a ring around the focus of the disease. "This is a realistic picture. But we are racing against time. We are racing against time," said Dr. Marie–Paul Kieny of the World Health Organization.
Portal "Eternal youth" http://vechnayamolodost.ru18.09.2014