Early Results From Ebola Vaccine Trial Called ‘Encouraging’

Chuck Bednar for redOrbit.com – Your Universe Online
An experimental Ebola vaccine caused no serious side effects and triggered a positive response in the immune systems of all 20 healthy volunteers who received the treatment, according to research published in Wednesday’s journal of the New England Journal of Medicine.
The vaccine, which is known as ChAD3, uses a modified chimpanzee adenovirus that was developed by researchers at GlaxoSmithKline and US National Institute of Allergy and Infectious Diseases (NIAID). It also includes genetic material from two Ebola strains – Sudan and Zaire, the latter of which is responsible for the current outbreak in West Africa – but no virus, meaning that it cannot cause Ebola hemorrhagic fever, according to Reuters.
The trial began on September 2, and the volunteers will be monitored for a total of 48 weeks to make sure they continue to remain healthy. While the main goal is to make sure the intramuscular vaccine is safe, the researchers also hope it will prove effective. So far, the results seem promising, according to Lauran Neergaard of the Associated Press (AP).
“The vaccine is designed to spur the immune system’s production of anti-Ebola antibodies, and people developed them within four weeks of getting the shots,” Neergaard said. “Half of the test group received a higher-dose shot, and those people produced more antibodies… [and] some people also developed a different set of virus-fighting immune cells, named T cells, the study found. That may be important in fending off Ebola.”
Prior research revealed that the immune systems of monkeys that had received the vaccine produced a similar response, the AP medical writer said. NIAID director Dr. Anthony Fauci, whose agency led the work, said that stimulating both types of immune response was a “promising” outcome. While no serious side effects were reported, two people who received the higher-dose vaccine had high-grade fevers which lasted no more than one day.
GSK chief executive Sir Andrew Witty told BBC News that the early data from the trial was “very encouraging,” and that if the trials continue to provide positive results, it could mean a viable Ebola vaccine could be available before the end of 2015. He added that the vaccine was “well tolerated” by the volunteers, and that while the trial was still ongoing, the trial “gives us very significant cause for optimism.”
“Whether it’s a breakthrough depends on making sure that all the rest of data over the next few weeks and months is in line,” Witty said. “We’ve been looking at a potential Ebola vaccine, we’ve been looking at its basic safety and whether or not it can generate an immune response in healthy volunteers – and the data is very encouraging. But we need to put it into context – this is a very accelerated development program and this is the first bit of data.”
According to the NIAID, the trial involved volunteers between the ages of 18 and 50. Ten of those individuals were given an intramuscular injection of the vaccine at a lower dose, and the other 10 received the same vaccine at a higher dose. Their blood was tested both two weeks and four weeks post-vaccination in order to determine if any anti-Ebola antibodies were generated. All 20 volunteers had developed such antibodies within four weeks of receiving the vaccine, the researchers said.
The ChAD3 vaccine is one of two currently undergoing clinical trials, the Center for Infectious Disease Research and Policy at the University of Minnesota explained in a statement. Two phase 1 studies of the Canadian-developed vaccine, which uses an Ebola virus protein spliced into a vesicular stomatitis virus (VSV-EBOV), launched in the US in October. Early results from that trial are also expected to be reported before the end of the year.
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