Vienna: A live vaccine based on the "Vesicular Stomatitis Virus" (VSV) has
yielded highly promising results for the rapid development of an
effective vaccine against the Ebola virus. This 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. In this context, Markus Müller, Vice Rector for Research and Head
of the University Department of Pharmacology, is acting within the
VEBCON study consortium as head of the "Data Safety Monitoring Board"
and is therefore jointly responsible for checking the vaccine's safety.
Michael
Ramharter especially, co-author of the study published in the New
England Journal of Medicine, from the University Department of Internal
Medicine I at the MedUni Vienna, is also involved. He has worked for 15
years at the Centre de Recherches Médicales de Lambaréné at the Albert
Schweitzer Hospital in Lambaréné in the Central African country of Gabon
(headed by Peter G. Kremsner) as head of the scientific working group
entitled "Infectious Disease Control Group", which was involved in the
carrying out of this first phase I Ebola vaccination study in Africa.
The international partners include Vienna and Lambaréné as well as a
centre in Kenya, together with the university hospitals of Hamburg,
Tübingen and Geneva.
Ebola antigen being inserted as a "Trojan horse"
"An
Ebola glycoprotein from the Ebola strain in Zaire is being inserted
into the VSV live vaccine", explains Ramharter: "While VSV only causes
mild symptoms in humans, the protein acts as an Ebola antigen and
triggers the formation of antibodies against the disease in the immune
system." These antibodies hide, almost like a "Trojan horse", in the
body in order to - successfully - fight the Ebola virus if the
individual becomes infected: "Just one vaccine has conferred one hundred
per cent protection against Ebola in the initial trials on primates",
says Ramharter.
As part of the phase I study which is now
complete and the results of which were published in the highly respected
journal "New England Journal of Medicine" on Wednesday (yesterday), 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. The most significant side
effect was found to be temporary joint pain and inflammation reported
among a small group of test subjects, particularly in the European
centres.
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. The first case of Ebola was reported in West Africa around
15 months ago. According to estimates, around 25,000 people have been
infected by the virus, with more than 10,000 of them having died since
as a result of this serious illness.
Service: New England Journal of Medicine
„Phase 1 Trials of rVSV EBOLA Vaccine in Africa and Europe - Preliminary Report“ NEJM, April 1, 2015. DOI: 10.1056/NEJMoa1502924.