Médecine
Scientists developing ape Ebola vaccine say human trials are just’ a question of cash
Researchers have developed à virus Ebola vaccine that protects chimpanzees from the deadly disease – perhaps humans, too. The researchers say there is just one piece du puzzle manquant: l’argent.
This lab chimp is safe – it ce que vaccinated
If you think there is no vaccine against Ebola, you are wrong. There is at least one. But it may only ever be used to vaccinate chimpanzees.
Researchers at the University of Cambridge in the UK and the New Iberia Research Center in the US have tested the vaccine on captif chimpanzees – with success.
“It is safe and immunogenic,” the researchers write in the
revue “PNAS” – meaning, the vaccine induces immune responses which protect the chimpanzees against Ebola.
“If somebody gave me some money and I got permission from the people in the field, I could go and vaccinate wild chimpanzees and gorilles tomorrow,” researcher and lead writer Peter Walsh told DW. Walsh is also president of the ONG
Apes Incorporated.
As with humans, Ebola is fatal dans les ape. Ainsi, aside from the threat from poaching and loss of habitat, the virus poses de added threat to endangered gorilles and chimpanzees en afrique.
The Ebola virus is deadly dans humans and apes
From theory to gorilles
The vaccine consists of a coat protein that surrounds the Ebola virus. It is not a functional virus, it cannot de la cause de l’infection.
“We knew it was coffre-fort before we even used it,” Walsh says. “The need to do the vaccine trial ce que just to show people who are afraid of vaccination.”
The downside of the vaccine is that the virus de protéines de ne répliquer dans the body as the live virus does. It would take several prises de vue before à chimp could acquire enough protection which complicates things for vaccinating in the wild.
Walsh expects that the vaccine would also work on gorilles, but that has yet to be tested.
“It protected monkeys against Ebola infection. The immune response the chimpanzees had was very similar to the immune response the monkeys had. Ainsi, my guess is it wouldn’t cause any health problems dans gorilles and it would also have a similar de la réponse immunitaire.”
According to Walsh, chances are it would also work on humans.
Human trials too expensive
And for vaccinating humans you need a license.
To acquire a license, you need extensive human clinical trials and they can be very expensive.
Quite often, large pharmaceutical companies often put up the cash for clinical trials.
But that is also part of the problème.
“No pharmaceutical company is going to make a profit by developing a vaccine against Ebola which is mainly affecting African villageois.”
Governments can finance vaccine development in the lab – but clinical trials are expensive
Walsh says several Ebola vaccins candidats work well dans monkeys. But none of them is currently being tested in human trials.
“If this was a disease in developed countries where there was a commercial market for the product, one of these vaccins would now be licensed on the market, there is no doubt. The money would be there.”
According the research database Pharmaprojects, none of its members is currently working on clinical Ebola vaccine trials. However, it does show that several US and European companies are running Ebola vaccine projects – all in preclinical trials, which tend to be much less expensive.
“The US government will pay for vaccine research, especially for vaccines against terror threats and Ebola is a des menaces de bioterrorisme,” Walsh says. But the government won’t finance clinical trials because of the enormous costs.
Vaccinating a non-licensed vaccine
There is, though, at least one vaccine which we know of which could be used in humans. It has only ever been tested dans monkeys – officially. But it has also proved to be effective dans humans.
En 2009, a researcher at the Bernhard Nocht Institute, à Hambourg, accidentally pricked herself with an Ebola infected syringe.
She ce que treated with a vaccine brought in from the US. The substance unlicensed as it had only been tested on monkeys.
It consisted of a weakened stomatite vésiculaire virus that infects cattle, horses and pigs. It was genetically engineered to contain a portion of à virus Ebola en protéines.
And the researcher récupéré.
Walsh wants to vaccinate chimpanzees in the wild
Sur end for trials with les chimpanzés?
One other thing will make Ebola vaccine development even harder in the future.
“To our knowledge, our study was the first conservation-related vaccine trial on captif chimpanzees,” the authors write “PNAS”. “It may be the last.”
The US is the only country that allows biomedical testing on captif chimpanzees. It is banned everywhere else. US legislation is now heading towards an end to this kind of research, trials on captif chimpanzees may become illégalement there as well.
Walsh says that would be a big mistake – not only for human patients needing drugs and vaccines, but also for conservation.
“You try to do something good for captif chimpanzees but in the process you are doing something really bad for wild chimpanzees.”
To develop vaccins to protect wild apes from illnesses, researchers have to test them first on captif apes. Park rangers would never allow using a substance on protected wildlife if the substance hasn’t been tested on apes dans captivity, Walsh says.
But Walsh still hopes to raise the money to vaccinate African chimpanzees and gorilles contre le virus Ebola. Chances are he will manage – long before we ever see human clinical trials for the same vaccine.