The world needed there is a vaccine for Ebola month to curb the epidemic that exploded in the west Africa, but none existed. Now the race is on to develop vaccines within months instead of years it takes generally. But even if one of the current candidates work, many questions remain. How long companies can make millions of doses of vaccine? When to begin production? And who will pay the bill for several million dollars?
At the end of a meeting of the World Health Organization (WHO) in Geneva, Switzerland, last week to discuss Ebola virus vaccines, several participants were convinced that the production mass of experimental products should start in parallel with studies to determine whether they actually work. "I go out all the stops," says Ira Longini, a statistician at the University of Florida in Gainesville who attended the meeting. "I'll try to do 30 to 40 million doses to cover the risk of West African populations . "
Jeremy Farrar, a researcher in infectious diseases and head of the Wellcome Trust in London, which provided funding for the vaccine against Ebola test agrees. "We may regret that we must take these vaccines immediately if they are found not to be effective," said Farrar, "but I think that is a risk we must take."
pharmaceutical giant GlaxoSmithKline (GSK) Rixensart, Belgium, is now testing a vaccine against the Ebola virus for volunteer safety no risk of contracting the disease. one second, made by NewLink Genetics of Ames, Iowa, is expected to enter clinical trials later this month. If the vaccine proves safe and capable of eliciting desired immune responses, previous consultation WHO has found broad support to short-circuit the progression standard vaccine trials and jump directly from these Phase I trials to Phase III efficacy testing in Liberia, Guinea and Sierra Leone, the three affected countries.
in early November, GSK plans to have enough data from the Phase I study to decide to launch Phase III trials, said Ripley Ballou, who heads the Ebola program GSK. workers-now health care broadly to include everyone in the hospital janitors for burial teams will be first in line. GSK earlier predicted he would have 10,000 doses by the end of the year that could be used in phase III trials, but Ballou said production has been going very well, and there may be up to 20,000 doses by then.
But it would be far enough doses to stop the epidemic in West Africa. That is why there is pressure to increase production of millions of doses from phase III trials start. What the world can not afford, Farrar said, is "to be in a position where the vaccine proves to be safe and effective in randomized small-scale trials and we have to wait 3-6 months to produce. "Doctors Without borders (MSF), which was the primary caregiver of the beginning of the epidemic, agrees." the production should be extended rapidly even before the final results on the effectiveness because it will allow that more people can benefit more quickly once the vaccine efficacy was demonstrated, "says Annick Antierens MSF, who was also at the meeting last week.
how many shots are available depend in part on the amount of product constitutes a "dose". GSK's vaccine tested at two different doses, and if the lower works, they have twice as vaccine. NewLink Genetics, a small business with less experience in vaccines, GSK is lagging, but safety studies could begin later this month. The doses tested in these trials will have an even greater reach. "If a lower dose proves to be effective, each bottle would yield several shots," said Gary Kobinger, a scientist who helped develop the vaccine to the Canadian Public Health Agency in Winnipeg. If this occurs, the amount of vaccine available multiply at a stroke.
Just how vaccinemakers fast can spit product has a great unknown. Even a multinational company like GSK, which has large vaccine manufacturing plants, is himself wondering how quickly it can make millions of doses given other vaccine production schedules. money is a problem, too. the funding for Phase III trials do not yet exist, Ballou said, let alone churning out millions of shots. "There is simply no budget model for this," he said.
Ballou said a "back of the envelope" calculation based mainly on staff costs shows that GSK could produce up to half a million doses for $ 25 million, and the cost would decrease with increased amount. But the company does not yet have reliable cost estimates for production on a larger scale, he said, especially given the fact that no one can accurately estimate how much is needed now or in the future, that the vaccine shelf life. Ballou made known so sure, however: "There are very significant capital investment from where we are now to what would be necessary for millions of doses"
Politically, order vaccine without. whether they will work hard to sell. Marie-Paule Kieny, Assistant Director-General of WHO, noted that there will be a lot of criticism if the vaccine is purchased as an insurance policy and not used. "At the end, when the analysis is done, people are still much more intelligent," she said.
Kieny should know. she led the WHO vaccination efforts during pandemic H1N1 in 09. Then, too, vaccine manufacturers have raced to provide several million doses, but most of them came after the pandemic had peaked in many places "people have said. Why you lose all this money on this vaccine, "Kieny said, and even could happen with an Ebola vaccine. "There will be inquiries, parliaments asking: How can you invest hundreds of millions of dollars in something that has not even been proven effective"
Many are looking to the US government to pay the bill, or most of it, but no commitment has yet been made. A US government is involved in these discussions and asked not to be named said the government helps to establish the efficacy studies as quickly as possible, and said their results should be expected "before large sums money must be invested in the scale of production. "the official assured that" things that can be done are now underway, including the transfer of technology. "
Even if the vaccine works, and is produced in large quantities, rolling on a mass scale will be a struggle, especially in places where there is mistrust of the government medical officials, big Pharma, and clinical trials in general. should be informed in advance the people in affected countries, but even that carries an ethical risk. They could prepare a vaccine that may never come, or may come too late, however, there is no choice, Kieny said a large education campaign "is very necessary and should start in early January. "
* Ebola files: given the current Ebola epidemic, unprecedented in terms of the number of people killed and the rapid geographic spread, science and science Translational Medicine made a collection of research and articles on viral disease available for researchers and the general public .
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