Research projects to prevent and cure the Ebola virus run at full speed. Among the most promising vaccines is a live vaccine, based on the Vesicular Stomatitis Virus (VSV). Univ.-Prof. Dr. Michael Ramharter from the MedUni Vienna is one of the researches developing this new vaccine.
Until now Ebola has killed more than 10.000 people in Sierra Leone, Guinea and Liberia. Still there are no proven treatments or vaccines to prevent people becoming infected. The reasons therefore explained Prof. Didier Pittet (WHO) in the Semmelweis Interview from 1 April 2015 (40 years ago, when we were for the first time confronted with the virus, the vaccines were not further developed, because there was no market and no money).
Due to the brisance, progress is now made on an unprecedented scale. Trials, which would normally take years or even decades, are accelerated many times over.
This is also the case with a live vaccine, based on the “Vesicular Stomatitis Virus” (VSV). The results, made until now, are highly promising. The vaccine would only need to be injected once for long-lasting immunoprotection. These are the key findings of an international study coordinated by the World Health Organisation (WHO) in which the MedUni Vienna also played an important role.
Co-author of the study (published in New England Journal of Medicine on 1 April 2015) Michael Ramharter from the MedUni Vienna: “An Ebola glycoprotein from the Ebola strain in Zaire is being inserted into the VSV live vaccine“, explains the Viennese reasearcher. The protein acts as an Ebola antigen and triggers the formation of antibodies against the disease in the immune system.” Just one vaccine has conferred one hundred per cent protection against Ebola in the initial trials on primates.
As part of the phase I study, which is now complete, 138 test subjects (healthy adults) were vaccinated with various doses of the live vaccine. The results are highly promising: “The vaccine response is very reliable, the vaccine itself is safe and its tolerability is acceptable”, says Ramharter.
In the phase II studies that are now starting, the vaccine will be used in patients living in the areas currently most badly affected by Ebola – especially Guinea and Sierra Leone, but also in Liberia, says Ramharter, who has worked for 15 years at the Centre de Recherches Médicales de Lambaréné in Gabon as head of the scientific working group which was involved in the carrying out of the first phase I Ebola vaccination study in Africa.