Positive early results for GSK/NIAID Ebola vaccine

A phase I trial on an experimental vaccine to prevent Ebola virus disease show it was well-tolerated and produced immune system responses in all 20 healthy adults who received it.

Co-developed by GlaxoSmithKline (GSK) and the US National Institutes of Health's (NIH) National Institute of Allergy and Infectious Diseases (NIAID), the vaccine was tested at the NIH Clinical Center in Bethesda, Maryland.

Dr Moncef Slaoui, chairman of Global Vaccines at GSK said, "It's important to remember that these data are the first piece in the jigsaw and we're continuing to gather other important information. Over the coming weeks, we will see results from further phase I trials which will tell us more about the profile of the monovalent vaccine; most significantly results from a trial in Mali which is assessing its safety and immune response in West African populations.

"If the combined data from these trials are positive, the next phases of the clinical trial programme will begin in early 2015 to see whether the immune response we are seeing in phase I actually translates into providing people in affected countries with meaningful protection against Ebola.

"These phase III trials will involve the vaccination of thousands of volunteers, including frontline healthcare workers in affected countries, including Liberia and Sierra Leone, and possibly Guinea. If the candidate vaccine is able to protect these healthcare workers as we hope it will, it could significantly contribute to efforts to bring this epidemic under control."

The candidate treatment was developed collaboratively by scientists at the NIAID Vaccine Research Center (VRC) and Okairos, a biotechnology company acquired by GSK in 2013. It contains segments of Ebola virus genetic material from two virus species, Sudan and Zaire. The Ebola virus genetic material is delivered by a carrier chimpanzee cold virus (chimpanzee-derived adenovirus 3 or ChAd3).

The trial volunteers all developed anti-Ebola antibodies within four weeks of receiving the vaccine. In addition, a T-cell immune response was found in many of the volunteers, including production of CD8 T cells, which may be an important part of immune protection against Ebola viruses.

Whether the test vaccine will be used in mass vaccination campaigns in in the future depends on whether the World Health Organization (WHO), regulators and other stakeholders are satisfied that it provides protection without significant side effects and how quickly large quantities can be made. GSK is investigating ways to accelerate manufacturing on an industrial scale if this is the case. It is also examining whether a booster vaccine may help provide longer-lasting protection.

Johnson & Johnson (J&J) and Merck are among others conducting similar vaccine trials, although these are unlikely to be ready until 2015, depending on trial results. Paul Stoffels, chief scientific officer at J&J, said there was a spirit of collaboration among pharma companies battling the Ebola virus and that he had been in regular communication with GSK CEO Andrew Witty on ways to accelerate possible treatments.

Link

J&J to accelerate Ebola vaccine, open to collaboration with rivals