Getty Images. A health worker stands behind the fencing of an Ebola quarantine and treatment centre in Monrovia, Liberia. |
With talk turning to the idea that Ebola vaccines and drugs may be needed to quell the West African outbreak, the tiny U.S. company that holds the licence for a Canadian-made vaccine says it is working as fast as it can to get that option tested and ready for use.
NewLink Genetics says at least five clinical trials involving the vaccine, known as VSV-EBOV, will soon be under way in the United States, Germany, Switzerland and in an unnamed African country which is not battling Ebola. As well, the Canadian government has said it wants to conduct a trial in this country.
Vaccine for these studies will be provided by the Canadian government, said a spokesperson for NewLink, which is based in Ames, Iowa.
Brian Wiley, the company’s vice-president of business development, said both the vaccine Canada donated to the World Health Organization and the remaining vials Canada was keeping back for clinical studies will be used for human studies.
Canada had roughly 1,500 vials of vaccine made for clinical trials before this Ebola crisis began. It offered 800 to 1,000 vials to the WHO and said the rest would be used for clinical trials. Each vial contains at least two doses of the vaccine and perhaps more depending on how much is needed for each injection.
“I believe all of those are now being put into the pool of available use for all the various clinical studies,” Wiley said in an interview with The Canadian Press.
“Some of those (studies) are going to be using the doses donated (to the WHO) by Canada, some of those will be using the doses set aside for us. So there is more than enough supply there.”
Canada recently said it wants to retain some supply for emergency use here.
Dr. Gregory Taylor, the new head of the Public Health Agency of Canada, said last week that the idea would be to put some vaccine in hospitals designated to treat Ebola patients, if any arrive. That way if a health-care worker looking after an Ebola patient had a risky exposure, he or she could be offered the vaccine.
Studies in primates have shown this vaccine works in primates both to prevent infection when given before exposure and increase survival chances when given quickly after exposure.
While it was initially thought some of the donated vaccine might be used to protect health-care workers involved in the Ebola response, the current thinking is that this and other experimental vaccines need to be tested for both safety and effectiveness before they can be used in the field.
The VSV-EBOV trials, two of which will be held in the United States, will test the experimental vaccine at different doses and in different population groups. The aim of these early trials is to see if the vaccine is safe for human use and how much vaccine is needed to generate what is hoped to be a protective response in people.
Later studies will be done to determine if the vaccine actually works.
While some experts had hoped for a more rapid roll out if the vaccine is shown to be safe in humans, sources have suggested the U.S. government wants to know the vaccine is effective before it and others spend what could amount to hundreds of millions of dollars.
The U.S. government paid for most of the research on both of the leading experimental Ebola vaccines. Its Biomedical Advanced Research and Development Authority which funds development of drugs and vaccines for pathogens that are deemed to pose a threat to the U.S. is currently helping NewLink manoeuvre the legal and bureaucratic hurdles involved in testing a new vaccine.
“They have been very co-operative with us,” Dr. Robin Robinson, who runs the BARDA, said in a recent interview.
The authority, a division of the U.S. department of health and human services, is also helping the company find vaccine manufacturers that could scale up to make what might turn out to be hundreds of thousands of doses of the vaccine if the vaccine works.
NewLink, which is developing cancer vaccines, does not have its own production facility.
Wiley understands that there is frustration at the time it is taking to launch the clinical trials but he suggested the work is moving at what amounts to warp speed for the vaccine world.
“There’s a lot of impatience…. And it’s difficult for people to understand on the outside looking in just how many things have to be done to move a drug through the process in the right way,” he said.
“It might seem like a long time to some but we really have done this in an extremely accelerated fashion.”
His comments suggest the company may have concerns that moving too quickly could jeopardize the future of the vaccine.
“Our primary goal is to do this in the most accelerated, most ethical way possible to ensure the likelihood of success,” Wiley said.
“If you do something wrong out of the gate and the (vaccine) is used at the wrong dose, or in the wrong patients or the wrong situation and you cause harm, the setback … can be disastrous. And so it’s really important that we do the right trials, that we do it in the right patient population and that we take the proper steps to evaluate and monitor those patients.”
The need for speed and the apparent slowness of this process have led some observers to privately question whether a company of the size and experience of NewLink has the capacity to see this project through to a successful conclusion.
The other leading Ebola vaccine candidate, created in the laboratories of the U.S. National Institutes of Allergy and Infectious Diseases, has been licensed to pharma giant GlaxoSmithKline (now known as GSK). The first clinical trial with that vaccine, called cAd3, began in early September.
Wiley said NewLink’s top priority is moving the Ebola vaccine forward. And he insisted the company has the help it needs to do the job.
“The resources that are being offered to us, should we need them, are more than enough to … get the job done and get the job done in a timeline that will be very accelerated to say the least.”
Helen Branswell
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